Environmental Geology Course Packet

This packet is divided into three sections:

Activities ……………………..………p. 3

Notes ………………………………….p. 43These notes correspond to PowerPoint notes presented in class. Additional notes and slides will also be shown in class.

Study Guides…………………………p. 67These may vary by instructor, and you will be told if these apply to your class. Additionally, the study guides may be modified depending on the pace of the course.

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ACTIVITY #1 Please write your answers on a separate sheet of paper.

a. Listen to the formal description of the Scientific Method and list the main steps usually associated with this method.

b. Describe how a hypothesis differs from a theory

2. Read the reading provided by the instructor:Provide a short list (at least three) of words that are unfamiliar to you. Provide the definition to each using either a dictionary, an encyclopedia (try the web), and/or class questions.

Describe the advantages and disadvantages of using multiple working hypotheses.

Do the advantages of using multiple working hypotheses outweigh the disadvantages?

How might a collection of scientists all working on the same problem use the method of multiple working hypotheses?

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Activity #2

a. If the growth of world population is 1.65% per year and the world population is now about _____________(find this number), how many new people will be added to the world during the next year? (Remember 1.65% means 1.65 per 100 or 0.0165). Show your work (the math)

b. Find the current population of the United States. What percentage of the world population does the U.S. represent? (divide U.S. pop. by World Pop. and multiply by 100 to express it as a percentage).

How does the US percentage of world population compare to the U.S. percentage of annual resource use? The US accounts for about 30% of all annual resource use (and about 25% of world energy resource use).

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ACTIVITY #3 Rocks and Minerals

What distinguishing features allow one to classify the compound known as “quartz” as a mineral?

Which igneous rock type makes up most of the continental crust and which igneous rock type makes up most of the oceanic crust

Which general type of rock covers most of the Earth’s surface

Which rock type is often stratified and what does it mean to say a rock is stratified?

How is foliation formed and how is it related to rock strength?

Which rock type is made of grains and how does formation of cement between grains change the properties of this rock?

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ACTIVITY #4 Geologic TimeWe will frequently be describing events in terms of geologic time. Geologists describe events in relative time and absolute time. Relative time is a comparison of a sequence of events. For example, one can order the events of their day using relative time. A person gets out of bed before eating breakfast, and this all happens before lunch. In the same manner, a geologist may say that a rock was formed before a river existed. Absolute time is a numerical quantity like the time we read from clocks. This primarily based upon the radioactive decay of elements. Statistically an element (such as Uranium) will change to a new element (such as lead) at a specific rate. This provides a clock and a specific time.Relative time: three principlesPrinciple of Original Horizontal: most sedimentary rock is deposited in a horizontal position (the lines of bedding are approximately horizontal)Principle of Superposition: In an undisturbed sequence of sedimentary rock, the lowest beds in the sequence were deposited first and are the oldestPriniciple of Crosscutting Relationships: A geologic features that crosscuts a body of rock (such as a fault) is younger than the feature being cut.

Use the principles to provide an ordered sequence, from oldest to youngest, of the features shown in the figure below. Indicate this sequence by listing the letters described below in the correct order. Note that the sequence of some events may not be certain. Which ones are those?

Use each letter to indicate the time when each feature formed:A= fault forms, B= layers 10,11,12 deposited (formed), C= layers 2,3,4,5,6,7 deposited,D= erosion of folded layers 2-7 and fault, E= folding of layers 2-7

Absolute Time: Radioactive decay. Radiometric dating uses radioactive elements that decay by emitting nuclear particles. These radioactive elements are called the parent material. In the decay process they are transformed into new elements called the daughter material. The rate of decay (how fast it occurs) is described in terms of a half-life. A half-life is the amount of time required for half of the parent atoms to decay to the daughter atoms. For example, one type of

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Uranium (235) has a half-life of 713 million years. The daughter product is Lead (207). This means that after 713 million years one gram of this Uranium parent would change leaving ½ gram of Uranium and ½ gram of Lead.

Consider the decay of Carbon-14. It has a half-life of 5730 years. Complete the graph below to show how 100% of the Carbon changes over four half-lifes.What percentage of parent is left after four half life’s, and how old is this material (after 4 half-lifes)?Material older than about 50,000 years cannot be dated using Carbon-14. What is the reason for this?

Bazard, 2013

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ACTIVITY #5

Write a brief description/definition of plate tectonics

b. Draw a profile of the earth from the surface down to the Asthenosphere. Identify the portions that are the crust, lithosphere, mantle, and asthenopshere (on back if you wish)

c. List the three types of plate boundaries and describe the relative motion between plates at the boundary.

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ACTIVITY #6 Consider the following blocks (a,b,c) and answer the following for eachdescribe the stress for each (tension, compression, or shear)for “a” and “b”, how will the dimension “l” change (shorter or longer)draw arrows on the front of blocks in a) and b) to show the sense of motion on the fault. Draw similar arrows on the tops of the blocks in c) to show the sense of motion.label each type of fault (not plate boundary)

Figures: Bazard, 2013

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Activity #7 (4 pts)

Refer to the map below and answer the following questionsa. Describe the difference between magnitude and intensityb. List at least 3 factors that determine the intensity at a specific sitec. Which town will experience the greatest difference between arrival of S and P waves

Figure: USGS Public Domain

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Activity #8 **** Use Tiny URL for THIS*****For this activity you will need to go to the Internet site listed below (URL). The discussion and exercises are designed to introduce the tectonic setting of our area and to provide an example of assessing the risks posed by frequent earthquakes. The last half of the web site includes the questions and activities listed below.

http://tinyurl.com/G10Earthquakes

Activity Questions and Requirements:

1. Regional Recurrence Interval. Calculate the recurrence intervals for large magnitude (6 or greater) and damaging (intensity VI or greater) earthquakes that have impacted Humboldt County in the last 160 years. To do this, use the earthquakes listed in the following pdf file: HumboldtEQs.pdf You will need to download and print this file or keep it open it in a separate window.a. Analyze the data and list the three longest and the three shortest intervals between earthquakes. b. Report the total number of earthquakes listed.c. Determine and report the recurrence interval for this entire data set by using the following calculation:Total years divided by the quantity of total earthquakes minus one. Formula: (total years) / {(total number of earthquakes) - 1}.Do you see why you divide by earthquakes minus 1? You could achieve this same result by adding up all of the intervals (7+11+2...) and dividing this number by the number of intervals present.d. Now recalculate the recurrence interval using only damaging earthquakes with an intensity of VI or greater. Your total years will be the same, but the number of earthquakes will decrease. Report this new recurrence interval.e. Is it likely to experience a large, damaging earthquake if you live in Humboldt County for a 10-year period? Explain.

2. Recurrence of Large Subduction Zone Earthquakes.Calculate the recurrence interval for large subduction zone earthquakes occurring on the Cascadia subduction zone.To do this, we will use estimates based on geologic evidence. This evidence suggests that 7 large subduction zone earthquakes (mag 8+) have occurred in the last 3500 years. The most recent one occurred on Jan 26, 1700 AD.Calculate the recurrence interval for these large subduction zone earthquakes. It will help to draw a time line to visualize how many intervals and the total time interval being considered.Note that newer geologic evidence indicates that these earthquakes occur more frequently than the analysis provided here suggests. This is a work in progress.

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3. Probability Determination:Go to the following USGS site to determine the probability of a greater than magnitude 6.0 earthquake occurring within a 50km radius of Eureka in the next 30 years. Use the zip code of 95501, time span of 30, magnitude of 6.0, No text report. The map generated will include a legend with numeric probabilities. A 1.00 probability is a 100% chance; a 0.50 probability is a 50% chance. Report the probability of Eureka and the probability for Ferndale: http://tinyurl.com/G10EQprobability

4. Earthquake Risk Assessment For the next exercise you will need to use the Humboldt GIS. You can open a window to this by selecting the following link and answer the underlined questions:http://tinyurl.com/G10hazardGIS

Once you have opened this window, go to the extreme left side of the map and click on the magnifying glass with plus sign (+). After you click on this symbol, move the cursor to Eureka on the map and click. Wait a moment and it should zoom in one level. Repeat this for a total of four or five clicks. This may take a few moments - be patient. You can zoom out by selecting the magnifying glass with a minus sign (-) and then clicking on the map. Also, you can click on the "hand" symbol and then click and drag the map to move the map around.Next, go to the extreme right side of the map and make sure only the following layers (under Map Themes) are "checked". You will have to uncheck a few of the layers lower on the list. uncheck all "layer" boxes except the following: Places Background Layers Water Bodies Then locate the two labels "Layers" and "Legend", above "Map Themes". After you change a layer box, click on legend to see and explanation of the colors or patterns that appear on the map.For this exercise you will go through each of the following layers and answer questions regarding the seismic risk associated with the area between Fortuna and Arcata.a. Check the Tsunami Evacuation Area box. List two locations that appear susceptible to tsunami. b. Uncheck the tsunami box and then check: Area of Potential Liquefaction. List two locations that appear susceptible to liquefaction. c. Uncheck the liquefaction box and then check: Seismic Safety. This layer is related to slope stability. What general areas have potentially unstable slopes? d. Uncheck the safety box and check: Earthquake Faults. What areas are near earthquake faults? e. Uncheck the faults box and then check: Earthquake Fault Hazard Zones. What areas are near these hazard zones? f. Check all five boxes you evaluated above to get a collective map of the earthquake hazards. Use this to describe specific areas that will experience the greatest damage in an earthquake. You may need to zoom in a bit on one area to complete this analysis. Your instructor may have you incorporate this answer into question number 5, below.

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g. Describe at least two additional factors related to seismic risk and safety that are not shown on this map. 5. Minimize Risk - Prepare for Earthquakes.List some actions one can take to minimize the impact an earthquake will have on your life (other than moving to a different area). You might consider looking at the "Living On Shaky Ground" link or the Red Cross site:http://www.humboldt.edu/shakyground/http://www.redcross.org/prepare/disaster/earthquake

6. Earthquake Risk Analysis.Write an essay describing the risk of earthquake hazards in this west-central portion of Humboldt County. Indicate which of the "Earthquake Sources" discussed above is a likely source for a damaging earthquake. Use the results of the recurrence and probability exercises to discuss the likelihood of a damaging earthquake in this region. Discuss specific areas prone to earthquake damage and discuss factors that may influence the risk, such as building types, preparation, and responses of people. This essay should address each of these areas, be typed (double spaced), and be no more than three pages long.

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The list below includes historic earthquakes that were felt, and in most cases caused damage, in the central Humboldt County area. The cutoff at 6.0 is arbitrary and it is possible for smaller earthquakes (such as Dec. 1994) to do more damage if located near populated areas. A more detailed list can be found at:http://web.archive.org/web/20061213072548/http://www.humboldt.edu/~geology/earthquakes/ncseismicity.gif

Date Locality Magnitude (est) Max Intensity (onshore)10/23/1853 Eureka (wharf sank 4 feet) (6?) VII11/13/1860 Humboldt Bay (chimney damage) (6?) VII3/2/1871 Petrolia (6?) VIII11/23/1873 Crescent City (6.7) VIII5/9/1878 Briceland (6?) VIII7/26/1890 Petrolia (chimneys fall in Ferndale) (6?) VII4/14/1899 Offshore Arcata (mill damage Eur.) (6.4) VI4/18/1906 San Francisco (damage in Hum Co.) (8.25) XI4/23/1906 McKinleyville (felt in Oregon) (6.4) VII10/29/1909 West of Scotia 6.4 VIII3/19/1910 Offshore Petrolia 6.0 V12/31/1915 Gorda Basin 6.2-6.5 III7/15/1918 W of Eureka 6.0-6.5 VI1/31/1922 Gorda Basin 7.3-7.6 I+1/22/1923 Offshore Cape Mendocino 6.5-7.3 VIII6/4/1925 west of Orick 6.0 I+12/10/1926 80 miles west of Eureka 6.0 II6/6/1932 East of Arcata (1 death) 5.9-6.4 VIII7/6/1934 56 miles west of Trinidad 6.5 II2/9/1941 Offshore Cape Mendocino 6.4-6.6 VI5/13/1941 Offshore Cape Mendocino 6.0 V10/3/1941 25 miles west of Petrolia 6.4 VII5/19/1945 Offshore Cape Mendocino 6.2 V10/8/1951 10 miles west of Petrolia 5.8-6.0 VII11/25/1954 W of Cape Mendocino 6.2 V12/21/1954 12 miles NE of Arcata (1 death) 6.6 VIII10/11/1956 W of Ferndale 6.0 V8/9/1960 Offshore Mendocino 6.2 V6/26/1968 Offshore Cape Mendocino 5.9 VII11/26/1976 93 miles NW of Eureka 6.3 IV11/8/1980 30 mi offshore Trinidad 7.0 VII8/17/1991 Honeydew (well changes) 6.2 VIII4/25/1992 3 miles east of Petrolia 7.1 IX4/26/1992 17 miles W-NW Petrolia 6.6 VII4/26/1992 16 miles west of Petrolia 6.7 VIII9/1/1994 88 miles west of Cape Mendocino 7.1 VI2/18/1995 88 miles W-SW of Eureka 6.6 V6/14/2005 90 mi offshore Trinidad 7.2 V1/9/2010 29 miles W-SW of Eureka 6.5 VII

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Activity #9

Refer to the Figure Below. The arrows show the current flow for a river1. How will normal river processes change the course of this river?a. Sediment will be eroded from the bank near house A, Sediment will be deposited near house B.b. Sediment will be deposited on the side near house A, Sediment will be eroded from the side near house B.c. Sediment will be eroded equally from both sides of the river, near both house A and Bd. Sediment will be deposited on both sides of the river, no erosion will occur.

2. The area covered between X and X’ includesa. the flood plainb. natural leveesc. channel, bed, and banksd. all of the above

Consider the setting and wave direction shown in the figure below. 3. Use an arrow to show the direction of longshore transport of sediment

4. If the waves approached the shore from the Northeast (reverse of picture), Which side of the jetties would experience erosion?

*****REDRAW THIS FIGURE AND SCAN*****

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N

E

S

W

X X’

Activity #10 Mad River Mouth Migration

The subject of this activity is the recent history of erosion of the McKinleyville Bluffs and the interactions of the people living near the dynamic systems of the Mad River and the Pacific coastline. The activity consists of two parts. The first part (#1) is a calculation of the rate of river mouth migration. The second part (#2) involves answering the questions below. This does not need to be typed, but it should be legible and the answers need to be on a separate sheet of paper.

1. (4pts) Use Figure 1 (next page) to determine the rate of northward migration of the Mad River mouth from 1954 to 1991. The map scale is 1inch=2000feet. Show your work.

2. (9 pts) Use the information enclosed in the following pages (text, maps, article from local paper), and your text book to answer the following questions:List the natural processes involved in the movement of the river mouth and channel and briefly describe how these influence erosion of the McKinleyville Bluffs.

List at least three significant changes people have made to the natural river system and the resulting consequences (these may be positive and/or negative consequences). These changes should include both older historic modifications as well as more recent (last 45 years) changes.

Discuss and describe how the changes you described in “question b” (above) may have influenced the migration of the mouth and the erosion of the McKinleyville Bluffs.

Provide a prediction of future river mouth migration and erosion, and your recommendations for addressing this situation. The recommendation might be the building of a preventative structure, zoning, or some combination of the two.

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Figure 1. Positions of the Mad River Mouth, 1942-1991. Use this for Question #1Modified USGS map figure

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****TRACE OR REDRAW THIS*****

Figure 2. Map of Mad River drainage basin

Prior to white settlement (people of western European descent), the Wiyot people (native Americans) occupied several settlements along the Mad River, including seasonal occupation near the mouth to take advantage of abundant salmon and steelhead runs (Figure 3). The large influx of settlers associated with mining and logging in the mid 1800s resulted in the dislocation (and genocide) of the Wiyots and in modifications to the river system, including bank stabilization and meander cut-offs. These actions were taken to prevent the river from migrating across agricultural settlements of the floodplain and as a response to the increased erosion that resulted from logging and clearing of bottomland vegetation. Levees were also constructed to increase the holding capacity of the channel such that a discharge of a 20-year (or greater flood) is required to top the channel banks. Previously, flood events occurring about every 5-years would top the riverbanks and empty into the sloughs that run to Humboldt Bay.Other modifications to the Mad River system include dams built upstream, gravel mining, and modifications to the coastal system that influences sedimentation at the river’s mouth. The Sweasey Dam, completed in 1938, was built upstream from Blue Lake (upstream from the hatchery) to act as a water supply for Eureka. It was removed (dynamited) in August of 1970 due to the large amount of sediment impounded behind the dam, and to allow fish passage upstream. The dam removal allowed approximately 3000 acre-feet of sediment to be washed down river. Another dam built farther upstream in 1961 impounds Ruth Reservoir/Lake (see Figure 2). This structure was built to supply water to the Humboldt Bay Municipal Water District and is still in place. The mouth of the river is also influenced by the jetty structures built at the opening of Humboldt Bay. The first jetties were constructed in 1889 and have since been periodically improved. These structures influence the transport of sediment along the coastline by trapping longshore-transported sediments and by directing sediment farther offshore. However, the specific influence of these modifications on the coastal sediments that are involved in the position of the Mad River mouth is not clear. Also uncertain is the influence of gravel extraction from the Mad River. Removal of this load may potentially influence the erosive nature of the river (less energy expended moving the bed load), but the specific cause and effect of gravel removal is open to interpretation.

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Mad River

Mad River

Figure 3. Map of Wiyot settlements and vegetation patterns in the Mad River Floodplain area (data from Loud, 1918). The settlements are located around the floodplain in areas with access to water for canoe travel and thus document the location of Mad River channel and Mouth in the early 1800s. (from the Humboldt State University thesis of Chris Haynes, 1986; used by permission).

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Figure 4. Map produced by the city of Arcata showing former and present positions of Mad River features. Note the mouth of the Mad River was near the present position of School Road in 1854. A color version of this map can be found at: http://library.humboldt.edu/%7Erls/images/mad_river_delta_1870_1997.jpg

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Another controversy involves the migration of the Mad River mouth. During the last sixty years the mouth has moved to various coastal positions near the McKinleyville Bluffs (or “uplands” in Figure 3). Figure 1 shows various positions of the Mad River Mouth from 1942 to 1991. The pattern of migration is one of slow northward movement, punctuated by sudden shifts to the south as the sand barrier between the river and ocean is eroded away. For example, the river moved south to a position near the current Mad River County Park during the 1955 flood when erosive floodwaters helped to carve a “shortcut” to the ocean (compare ’42 and ’54 (should be 55) positions in Figure 1). A rock-slope barrier was built by the California Department of Transportation (CalTrans) in 1992 to prevent further northward migration of the mouth at that time (Figure 5). This was done to prevent the river from eroding northward into Highway 101 at Clam Beach. The barrier prevented northward migration of the mouth, but the river began to erode around the barrier and into the bluffs. In the spring of 1999 the river carved a new channel to the ocean near the former mouth at Hiller Road (Figure 5). Since that time, the mouth has again continued to migrate northward (note 2006 position in Figure 5).

Figure 5. 2006 satellite image of Mad River mouth region (modified from Google Earth). McKinelyville and Highway 101 are located to the right of the Mad River.

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River Mouth, 2006

CalTrans Rock-slope Barrier

Murray Rd

Hiller Rd

School RdMad River County Park

Tyee City, bank

ADDITIONAL INFORMATION WILL BE PROVIDED BY THE INSTRUCTOR

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ACTIVITY #11: Grade of Slopes and topographic maps

Slopes (or grades) are often described in terms of percent. The percent is the vertical change divided by the horizontal change times 100 (to be expressed as a percent):

A 25% slope is where the vertical change is 25% of the horizontal change. For example, you

move 100 meters horizontally and drop 25 meters: Note that the percent of a slope is not the angle of the slope. In fact a 100% slope (which is so steep it is difficult to stand upon) is a 45° dip.

Part I Determine the percent grade for the followinga. An elevation change of 20 meters across a horizontal distance of 60 meters

b. A change from an elevation of 225 feet to an elevation of 300 feet, across a horizontal distance of 200 feet.

[to determine the angle of each slope: tan-1(rise/run)]

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Part II – Answer questions for the topographic map provided

a. What is the approximate distance (in feet between points F and B)?b. What is the contour interval for this map? Look at the number of intervals between the 600 and 800 foot contour lines.c. Calculate the % grade between the hilltop at 1062 and Point D. You will need to measure the distance using the map scale and determine the elevation change from the contour lines

From: O.L. Huber, and T.E. Spittler, 1995 Redway Landslide, California Geology, Calif. Div. Mines and Geol., Nov/Dec. 1996.

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Part III

Redway Landslide On March 13, 1995 a 15-acre landslide removed about 400 feet of the major county highway and partially dammed the South Fork of the Eel River. Landsliding was not new in this area. In 1980 the roadway was disrupted by landsliding at the same location, but the amount of slide movement was much smaller.

Details of the slide: The landslide began as a rotational slump, and accelerated when it transformed into a very wet, rapidly moving earthflow. The initial rate of movement of the earthflow was rapid to very rapid. By late April movement had slowed to a moderate rate (1 foot per day). By May 17, most of the surface of the slide was dry enough to walk on. The surface of the landslide slopes about 18%, except for a nearly vertical 10-15 foot high scarp at point F. The slope flattens to 5% between points A and H and from H to I it steepens to 20%, and becoming still steeper (37%) between J and K. From G to H, the landslide surface is generally lower than the original ground and is called the zone of depletion. Between H and L the surface is higher than the original ground and is called the zone of accumulation.

Geology: The area is underlain by a bedrock of marine sedimentary rocks. Observed outcrops are composed of sandstone, conglomerate, and shale. The rock is well cemented in some locations and fairly resistant to erosion. It has a tendency to create steep slopes and bluffs during weathering and erosion. At least two sequences of unconsolidated river terrace deposits cover the bedrock.

Land Use: The Redway landslide is on commercial forest land, state park land, county road right of way, and a river channel gravel bar. The commercial forest land has been periodically logged, starting before 1941. The most extensive logging was between the late 1950s and early 1960s, and the large old growth trees were removed before 1963. Some second growth trees on the private property were logged in 1991, upslope from the area of initial slide movement (but substantial tree canopy remained following the logging). The state park is covered with undisturbed old-growth mixed conifer forest, which includes redwoods as much as 10 feet in diameter. A dewatering trench filled with porous gravel that drains into a perforated pipe (French drain) was installed 15 feet beneath the roadway to dewater the problem area that slid in 1980.

On a separate piece of paper, write (or type) your answers to the following:

a. List the type(s) of mass wasting that occurred.b. List the materials and forces that kept the hillside in place prior to this mass movement event. In other words, what were the resisting forces?c. List the materials and forces that caused this downward movement. In other words, what driving forces moved this material down slope?d. Discuss what may have caused this landslide (both immediate causes and longer-term causes).

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From: O.L. Huber, and T.E. Spittler, 1995 Redway Landslide, California Geology, Calif. Div. Mines and Geol., Nov/Dec. 1996.

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Activity #12 – Ground Water Contamination

Figure 1, Map of contaminated waterfront sites; some degree of cleanup has occurred at all of these sites. (Figure: Times Standard, April 29, 1996). The Balloon Track site is at location number 6 (Southern Pacific yard).

Industrial Activity and Site ContaminationSoil and groundwater contamination occur at several sites along Eureka’s waterfront (see figure above). Past industrial activity has resulted in oil and gas spills as well as less frequent occurrences of heavy metals, chlorinated compounds (such as polychlorinated biphenyls or PCBs), and other chemicals in the soil and groundwater. The former Eureka railroad yard, or Balloon Track, is among these contaminated sites (however PCBs have not been found in the soil or groundwater at this site). The following information concerning site contamination has been summarized from reports commissioned by Southern Pacific Transportation Company (on public record at the Humboldt County Department of Health, Environmental Division), site visits, newspaper articles, U.S. Environmental Protection Agency documents, and from the maps and aerial photographs.

The Onset of Environmental AwarenessContamination has occurred at the former railyard throughout its industrial history. Early in the 20th century a former marsh was filled and industrial activity began. This site was used as a location of railroad fueling and repair for almost 80 years. In addition, above- and below-ground storage tanks were installed on this site and on adjacent parcels. Most of the environmental consequences of these activities went unchecked prior to the early 1970s when environmental standards were implemented. In 1974 the Regional Water Quality Control Board issued a spill prevention measure to control the runoff of oily-water into Humboldt Bay. Northwest Pacific Railroad (the operator at the time) estimated that 5000 gallons of oily storm water was being discharged into the bay per day as a result of rain runoff. A year later, they installed an oil collection system and an oil-water separator system to control this problem. This system was operational until 1986 when site use had decreased significantly. The oil-water separators were

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sealed; however, some of the former drainage ditches (and newer drainage ditches) used for surface runoff were not maintained and still collect and channel surface water into Clark Slough.

Legislation that required removal of old underground storage tanks led to a 1988 request for Southern Pacific Transportation Company to have underground storage tanks removed from the site. According to a report from an environmental services corporation at the time of the tanks’ removal in 1988, no detectable concentrations of petroleum-associated compounds were found in the soil surrounding the tanks. However, nearby groundwater samples collected during this activity contained 0.69 parts per million benzene, 1.10 parts per million toluene, and 1.2 parts per million xylenes (all are components of gasoline). The benzene levels were considerably greater than the maximum contaminant level standard for drinking water (see the attached table of accepted values and health risks). Interest in using this site as a possible location for the Humboldt County Jail led to new environmental investigations in the late 1980s. Soil and groundwater samples indicated the presence of oil, grease, petroleum hydrocarbons, and lead. Neither pesticides nor PCBs were detected. The environmental consultants for this project recommended that the site be remediated (cleaned-up) before development of the property. The site was not chosen for the Humboldt County jail. In 1989 the Regional Water Quality Control Board requested that Southern Pacific Transportation Company assess soil and groundwater quality beneath the former railroad yard and conduct the appropriate clean up actions. An environmental consulting company was retained to assess the site, remove potentially hazardous materials, and make recommendations for further clean up. A total of 980 gallons of uncharacterized oil was removed from the site. Waste materials were either transported to a recycling facility or disposed at a facility in Kettleman City, California. Approximately 3500 gallons of oily wastewater was removed from the oil-water separator system and transported to a recycling facility. The inoperative oil-water separator was sealed. Exploratory boring and trenching was conducted to assess the subsurface soils and groundwater samples were collected to evaluate the distribution of contaminants beneath the site. Three general areas of soil contamination (in the upper six feet of soil) were identified. The areas are 1) the former railroad tracks from the service platform to the turntable, 2) the Bunker C oil tank area, and 3) the area around and south (up to 150 feet) of the former roundhouse (see attached site map). These areas contained 100 to 42,000 parts per million of total petroleum hydrocarbons in the upper six feet of soil. Localized stained soil was observed in these former operational areas. The material was characterized as diesel and as oil and grease. Benzene and xylenes were found in two soil samples at concentrations of 1.7 and 21 parts per million respectively. Metal concentrations in the soil were well below the safety limits for the particular metals. The highest concentrations were for lead at up to 374 parts per million. The consultants stated that the volatile organic compounds (including benzene and xylenes) were “insignificant” and they emphasized that the lead was reported “only” in three samples. They concluded that the petroleum hydrocarbons (primarily diesel and crude oil) were the primary compounds of concern. Comparisons of contaminant concentrations at these locations over several years indicate that the concentrations are stable and have been decreasing over time. Accordingly, further active remediation in this area has been deemed unnecessary. The current course of action appears to be one of passive remediation. From 1989 to present soil and groundwater samples have been periodically collected and analyzed for a variety of contaminants related to former industrial activity. Relatively low levels of contaminants (below maximum contaminant levels for drinking water) have been found in groundwater of both the upper A Zone and the lower B Zone. In general, these analyses show that the greatest volume of contaminants is degraded diesel-range petroleum hydrocarbons limited to the former storage tank and refueling areas.

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These studies also show that the upper soil contains low levels of lead (2 to 1800 part per million) and arsenic (1 to 93 parts per million). The arsenic is possibly due to the use of pesticides and herbicides near the railroad sidings. Further actions regarding concentrations of lead in the soil was not mentioned in the recommendation of a 1999 study of the site. However, that same year consults hired by WalMart submitted a proposal to the Regional Water Quality Control Board for a study to include evaluation of the presence of both heavy metals and arsenic.Contractors hired by Union Pacific (formerly Southern Pacific Transportation Company) periodically collected trash and cleared brush at the site and subsurface remediation continued under a policy of passive remediation. In the mid 2000s the property was purchased by Security National Properties who is the current owner. Security National has proposed a mixed-use development for the site; however, controversy regarding the cleanup and use of this site continues. This controversy regarding the site remediation has resulted in litigation and a request for remediation beyond what was originally planned by either Union Pacific or the Security National (current owner). Soil sampling conducted by Humboldt Baykeeper (as the result of litigation) revealed "hot spots" on the property with significant levels of contaminants such as dioxins, metals, and arsenic. Fish tissue sampling in Clark Slough found dioxin in an amount four times higher than the "Do Not Consume" level set by U.S. EPA. In addition, the California Coastal Commission has jurisdiction over land use of the property and conflicts between Security National and this governmental agency have led to a delay in development of the site. These later issues have been the topic of litigation; more details about the current state of affairs will be described in class.

The following website provides details regarding this site. This includes photos, a discussion of dioxins, and links to a California State interactive map (Geotracker) that provides specific records of groundwater analyses from the monitoring wells of this site.

http://tinyurl.com/Balloon2011 or the direct site URL:

http://msemac.redwoods.edu/~dbazard/Geography/Groundwater/index.html

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Construct a Cross-Section of the Balloon Track Site and Questions 1. Use the enclosed data and graph paper (provided in class) to construct a diagram that shows the subsurface geology of the site. The data are from three wells located on a northeast-southwest line through the property (see web site figure; A paper copy will be provided in class).

Well DataWell MW-2 (northeastern portion of property)0 to 1 feet: Sandy Gravel (Fill): dark grayish brown, 55% gravel to 3 inches, 40% fine sand1 to 7.5 feet: Sand (Fill): dark greenish gray, 95% fine to medium sand, shell fragments7.5 to 11.5 feet: Clay (Bay Mud): dark greenish gray, 95% silt and clay, trace roots11.5 to 30 feet: Sand: dark greenish gray, 95% fine to medium sand, shell fragments

Well MW-3 (middle of property): 400 feet southwest of well MW-20 to 2 feet: Gravel (Fill): brown, 60% gravel, 35% fine sand, wood fragments2 to 7 feet: Sand (Fill): dark bluish gray, 95% fine to medium sand, shell fragments7 to 8 feet: Clay (Bay Mud): 95% silt and clay, roots, organic rich zone at top8 to 8.5 feet: Clay with sand (Bay): 80% silt and clay, 20% sand, roots8.5 to 12 feet: Clay (Bay mud): 95% silt and clay12 to 30 feet: Sand: dark greenish gray, 95% fine to medium sand, trace shell fragments

Well MW-5 (southwestern portion of property): 900 feet southwest of well MW-3; 1300 ft SW of MW-20 to 2 feet: Sandy Gravel (Fill): dark grayish brown, 55% gravel to 3 inches, 40% fine sand2 to 7.5 feet: Sand (Fill): dark greenish gray, 95% fine to medium sand, shell fragments7.5 to 10 feet: Clay (Bay Mud): dark greenish gray, 95% silt and clay, trace roots10 to 12.5 feet: Sandy silt: dark greenish gray, 60% sandy silt, 35% clayey sand12.5 to 40 feet: Sand: dark greenish gray, 95% fine to medium sand, trace shell fragments

Orient the graph paper so the longest dimension (11”) is horizontal and the minimum dimension (8.5”) is vertical (a landscape view). Make a vertical line for each well. Use an appropriate horizontal scale to space the vertical lines along the 1300 feet of horizontal distance between wells MW-3 and MW-5.Use an appropriate vertical scale to accommodate the 40 feet of depthWrite your scales on your graph paper (for example, one block = 10 feet)Use your scale to plot the thickness of each sedimentary unit on the vertical lines.Connect similar units between the three wells (using horizontal lines)Use a symbol (shading, dots, dashed lines, etc.) to show each sedimentary unitProvide a key to show the symbol associated with each rock type.

2. Monitoring wells show that groundwater inhabits two discrete stratigraphic zones beneath the site: the upper “A zone” and the lower “B zone”. These zones are separated by an aquaclude. Identify Aquifers A in B in your stratigraphic cross section.

3. Explain how the aquaclude may have controlled the migration of contaminants.

ACTIVITY #13 ENERGY

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N

Cross-section Li

1. a. Assume World Crude Oil Resources are about 1800 billion barrels. If the world uses about 30 billion barrels a year, how long will this supply last?

Assume the number in part a (1800 billion barrels) is pessimistic. Instead repeat the calculation using a more optimistic assessment of 2400 billion barrels of world oil reserves. How long would this larger supply last?

What assumptions (other than accuracy of the numbers) were made in the analysis of questions #1 and #2. What else needs to be considered for predicting how long supplies of this resource will last?

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2. A recent report from California Energy Commission cited the rate of California oil consumption as 71 million gallons per day.

a. How many gallons is this in a year?

b. If a barrel of oil is 42 gallons, how many barrels of oil does California consume in a year?

c. Assume the Arctic National Wildlife Refuge holds 10.4 billion barrels of oil. How long could it supply California with oil, if that was the only source for California and if the rate of consumption stayed at the 71 million gallons per day?

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Activity #14 – Oil and Gas Deposits

Part I – 5ptsList the basic steps for formation of oil and gas deposits. You may need one more or fewer steps depending how you combine or separate the basic requirements for formation.

Basic Requirements for Oil/Gas Formation

1.

2.

3.

4.

5.

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PART II – Written Discussion Read the enclosed articles and answer the following questions on a separate sheet of paper.

1. Explain why the Bakken Formation is considered a source rock and why it was initially difficult to extract oil from this rock formation.

2. Explain how the oil in the Bakeen Formation fits the model of oil formation you provided in part one (above). Is there any aspect of this deposit that doesn’t fit the model you described?

3. Why do oil companies use “fracking” as a method to recover oil? Describe the general process of “fracking” used to extract oil from rock. What materials/fluids are used to “frack” the rock?

4. What are some possible negative consequences of fracking?

5. Do you think “fracking” should be allowed? If so, what types of regulations (if any) should be applied?

The Information for this assignment will be provided in classhttp://tinyurl.com/Geo10Frack

http://tinyurl.com/Geo10Frack2

http://tinyurl.com/Geo10Frack3

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PowerPoint Notes

The notes provided on the following pages correspond to some of the PowerPoint slides used in the lecture sessions. These notes are provided as a general guide to the topic information; however, each instructor may modify their notes and the student is responsible for recording the specific information provided by the instructor.

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Environmental GeologyHow the earth impacts humans: Geologic processes: “hazards” Resources: water, minerals, soil, plant/animalHow humans impact the earth: population Resource extraction - natural systems / cycles Agents of erosion Contamination - concentration of natural and artificial compounds Climate change

Fundamental Concepts: Scientific method, Systems, Population, Geologic Time, Rock types, Plate TectonicsScientific Method: what are the basic elements?CuriosityObservations, Data (facts?)HypothesisTesting, Experimentation, AnalysisRepeat (Science is an ongoing process)

Observations: Data/FactsCan be “seen” be anyoneThe foundation of any scientific studyShould be distinguished from interpretationsExample: Soil type, shade, amount of water in the soil,steepness of slope

Generalization: A hypothesisUse the specific data to make a statement about thegeneral caseMultiple hypotheses are useful to prevent a bias towarda favorite ideaExamples: These plants grow in dark soil on north facingslopes. These plants can be found in any marsh

TestingA controlled experimentMust be repeatableMultiple TestingCan hypotheses be eliminated?Repeat: Modify hypothesis, more data!

Science: An On-going ProcessTheories are rare: a hypothesis that has passednumerous repeatable tests. Considered by many to betrue.

Theory - has passed repeated testing The best explanation of the day; theories are rare.The explanation that is most consistent with the observations. Considered by many to be true.

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Science: An On-going ProcessTheories are rare: a hypothesis that has passed numerous repeatable tests. Considered by many to be true.

Fact?? A directly observable phenomenon. Is Plate Tectonics Fact?Role of uncertainty in science?Science and the Human ElementRuling TheoriesParadigm ShiftsEgo, Bias, Ethics and Intellectual DishonestyDoes Science Satisfy the Spiritual?Concepts of: Systems, Cycles, Reservoirs, Residence TimeSystem: Portion of the universe isolated from the rest for the purposes of observationOpen System: Material moves in and out (ex: river)Earth as a closed system (to material) Is it absolutely closed?Material cycles between various open systems within the closed system (example: hydrologic cycle)Material stays in a reservoir for a given amount of time: the Residence TimeEarth is an open system to energy exchangePopulation Current World Population: ~6.7 billion (6,500,000,000)U.S. Population: ~300 million (300,000,000); 5% world population, but use about 25-30% of world resources

Exponential Population GrowthGrowth is a percentage of previous amountPopulation of 100 growing by 2% will be 102 the nextyear; net growth is 2.% is amount out of 1002% of 6 billion is: 2/100x6,000,000,000=120,000,000Net growth (including deaths) is 120 million

Summary: Fundamental ConceptsScience is a way of understanding/appreciating our worldand predicting future outcomes

Earth is a closed system to material

Population influences resource use, availability, andsustainabilityPopulation influences perceptions of “hazards” and the“cost” of hazards (in life and property)

Goal of sustainability: Nature, Species, Quality of Life,Future Generations

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Fundamentals of GeologyI Earth Structure

The Crust Continental Crust - Granite RockOceanic Crust - Basaltic Rock

The MantleDense, Iron-Magnesium Rich Rock, Flows over long periods of time

The CoreLiquid Outer CoreInner Solid Core

Lithosphere / AsthenosphereLithosphere: All of the crust and the uppermost mantle, Brittle (rigid),50-100 km thick, The “plates” of plate tectonics

Asthenosphere:Part of the upper mantle, Plastic / semi-fluid layer, Beneath the lithosphere, down to ~600 km

II Plate TectonicsTheoryCrust and Uppermost Mantle (Lithosphere) is broken into Rigid segments that move relative to each other.Evidence: Matching Outlines, Biological Associations, Rocks, and Glacier Features of Continents, Magnetic Data, Direct Observation (from Satellites)

Three Types of Plate BoundariesDivergent: Plates Spread Apart; Basaltic Magma Produced: New Plate Created

Convergent: Plates Push Together; Oceanic Plate Destroyed: Subduction

Transform: Plates move Side-by-Side (parallel)

III Materials (rocks)

Igneous Rock: Crystallized From Magma

Intrusive (plutonic) igneous rocks are formed when magma cools slowly deep beneath the earth. Example: Granite

Extrusive (volcanic) igneous rocks are formed when magma at the surface (lava) cools rapidly. Example: Basalt

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Sedimentary Rock: Cemented SedimentMudstone (Shale), Sandstone, LimestoneCharacterized by grain sizes and/or composition (limestone=calcite rich)Commonly stratified (layering)Range from poorly cemented to well cemented (soft to hard)

Metamorphic Rock A pre-exisiting rock,changed by Heat and/or Pressure (without melting)Examples are Slate and Schist Commonly have a parallel “fabric or grain” called Foliation. Foliation is like bedding and rocks may break along foliation

Significance To Environmental GeologyIgneous Rocks: Typically Strong BedrockVolcanic Rocks Indicate Possible HazardTectonics:Continental Crust=GraniteOceanic Crust = Basalt

Metamorphic Rocks: Weak to Strong. Fractured and/or Foliated Rock may be weak parallel to fractures

Sedimentary RocksStrength: Mudstones and Poorly Cemented Rocks Can Be Weak. Failure Can Occur Along Bedding Planes. Well-Cemented Rock Can Be A Strong BedrockPorosity: Applications to Groundwater, Oil and Gas Formation

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Earthquakes, Fault TypesFault: A fracture where motion occurs between opposite sides.

Dip-Slip Faults (Vertical Motion)Normal Fault: Horizontal Tension (Vertical Compression), Lengthening, Hanging Wall drops down

Dip-Slip Faults (Vertical Motion)Reverse Fault (or “thrust” fault): Horizontal Compression, Shortening, Hanging Wall moves up

Strike-Slip Faults (Horizontal Shear)Right-Lateral: Objects across fault move rightLeft-Lateral: Objects across fault move left

ELASTIC REBOUND THEORYRock is stressed and deformsRock Deforms, Will “Snap Back” if Stress is ReleasedRock Breaks, Each Side “Snaps Back”. Energy Is Released As Seismic WavesRock on each side returns to undeformed state, slip occurs along the fault; stress begins to build again

Focus: Central Point Where Breaking BeginsEpicenter: Surface Point, Directly Above Focus

Seismic WavesEnergy Moves Through Rock As WavesWaves Move As An Expanding Shell

Two General Wave TypesA. Body WavesP-Waves=Compressional or Primary Waves; Particle Motion Parallel to Wave Motion; 6km/s.S-Waves=Shear or Secondary Waves; Particle Motion Perpendicular to Wave Motion; 3.5Km/s.

B. Surface WavesGround Roll, This causes damage; Energy guided along surface, Slowest Wave, Greatest Damage: Ground Roll

Seismograph: Machine that records Seismic Waves. Mass Suspended From A Spring.Seismogram: A paper (or visual) record of seismic waves. Note 3 types of waves recorded.

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Magnitude: A measure of the energy released from an earthquakeIndependent of Distance and LocationDepends on strength of rock, area and amount of slipOriginally calculated using Amplitude of Largest Wave and a Correction for Distance to the EpicenterMany Magnitude Scales: Each calculated using either different wave forms or other information. Examples: Body-Wave Magnitude, Duration Magnitude, Moment Magnitude, Local or Richter Magnitude

Magnitude: Wave Amplitude increases 10 times for each unit of magnitudeEnergy Released increases 30 times for each unit of magnitudeAn Example:Earthquake Magnitude Amplitude Units Energy Release Units3.1 1 14.1 10 305.1 100 (10x10) 900 (30x30)6.1 1000 (10x10x10) 27,000 (30x30x30)

Intensity: A measure of the shaking that occurs at a locationIntensity depends on distance, rock type, and magnitude

Shaking: Geologic Materials and Wave AmplificationsPoorly-cemented (“soft”) and water-saturated materials will amplify seismic wavesShaking may be more extreme at a location if structures are on soft sedimentsWater-saturated rock may liquefy during shaking: Liquefaction

Tsunami: Seismic Sea WaveVertical Displacement of Sea Water: Subduction Earthquake, Landslide, VolcanoOpen Ocean: Long Wavelength: 100-200km, Waveheight: <1 m, Speed: up to 800km/hrNear Shore: Wavelenth Shortens, Height Increases: up to 30 meters!

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PredictionGeologic / Tectonic Setting: Most occur near plate boundaries; Largest at Convergent BoundariesPast History: Cycles and ProbabilityStress/Strain Builds to produce eventsRecurrence Intervals: Time Between EventsSeismic Gaps: Higher Probability?Recorded Histories: Seismograpms, Written RecordsOral Histories: Native American Geologic Evidence: Trenching, Landforms

Short-Term PredictionRelated To Ground DeformationForeshocksGround Level Changes: Surveys/GPSGround Water ChangesElectrical/Magnetic ChangesAnimal BehaviorRelease of Radon GasShort-Short Term: P/S Wave Difference

Preparation / PlanningIdentify Vulnerable Areashistorytectonic settinglocal geologic / geographic setting

Education / Zoning

PreparationBuilding Codes / EngineeringHome ModificationsSupplies / Emergency Responses

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River Processes* Erosion and Transport of Sediment* River Morphology* Meandering of Channel / Migration of Mouth* Floods: Prevention / Preparation (Adjustment)

Erosion and Transport of Sediment* Rivers migrate and erode sediment from their banks* Rivers are an agent of sediment transport.* Deposition occurs as the stream slows- Large sediment is deposited in fast moving water (higher energy)- Fine-grained sediment is deposited in slower moving water (lower energy)* Fine-grained sediment is deposited as rivers spread out across a floodplain.

River Morphology*Channel: Bed and Banks*Natural Levees: Deposition of sediment during flood periods (greater than bank-full discharge)*Floodplain: flat surface adjacent to the river channel, periodically inundated by floodwaters (every 2-5 years)*Rivers flow from headwaters to the mouth (location of a delta). Include tributaries that flow into the trunk stream.

Slope or gradient: vertical drop per unit of horizontal distance (grade)Profile: change in gradient over the course of the streamTypically the profile is steepest at the headwaters and flatten to the base level.-Streams erode headwardChanges in uplift, rate of erosion, discharge, and base level effect the stream profile

Drainage BasinsThe region drained by a river or river system (same as watershed)Drainage basins are separated by drainage dividesDrainage basin is defined by the river of interest. A river has a drainage basin that includes the drainage basins of all its tributaries.

Meandering of Channel Sinuous river channels are called meandersA meander bend includes an outer cut bank and an inner point bar.Cut bank=area of erosionPoint bar=area of depositionMeanders migrate over time

River mouths also migrateDue to meandering of the riverDue to river captureDue to blockage by longshore drift

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Braided Channels: some channels have a braided patternoften due to high sediment load and a steep gradientchannels tend to be wide and shallow

Land-Use ChangesRivers maintain a rough balance (equilibrium) between work done and sediment load.* Gradient and cross-sectional area provide a velocity necessary to do the work of moving the sediment load.* Increase or decrease in water or sediment brings about changes in the channel shape and slope. This can change water velocity* Land use changes influence sediment load and water. Thus they may result in a series of changes in the river equilibrium.

Floods: Flood=greater than bankfull dischargeDischarge: Area (mxm) x velocity (m/s)units of cubic meters/sec (or cubic feet /sec)A function of: total distribution of precipitation in the drainage basin; and/or snow melt, rate of infiltration, topography, land use changes,

Hydrographs: discharge per time

FloodsUpstream Flood - upper drainage basin, short duration.Downstream Flood - involves more tributaries, longer lag time, longer duration.Structural Failure - Dam / Reservoir Failure

Flood Recurrence Probability of a Flood of a Given Size Based on past records (better estimate with longer records) Probability changes as climate, runoff, etc. change

Probability of a FloodBased on Past HistoryOnce in a 100 years = 1/100=0.01=1%5 times in 100 years = 5/100=0.05=5% 5/100=1/20=“20-year flood” = 5% chanceThis gives probability (chance) of a discharge of a given size happening Any Given Year A 1% chance (100 year flood) A 5% chance (20 year flood) A 20% chance (5 year flood)Flood Prevention / Preparation (Adjustment)

PreventionLeveesFloodwallsReservoirs

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ChannelizationThese can lead to larger downstream floods, false sense of security (increase development), can make floods worse (more costly)

Preparation (Adjustment)Learn to live with the River SystemRecognize value of the floodplainFloodplain regulation, hazard mapsRequires Zoning and Planning - delineate past floods or floods of a particular frequency (e.g., 100-year floodplain). Restrict development.

Coastal ProcessesLongshore Current -Longshore Drift of SedimentsSources of Sediment Input and OutputCoastal Features: Spit, Baymouth-Bar, River MouthCoastal ManagementStructures: Jetties, Breakwater, Sea wall“Beach Nourishment”Planning and Zoning (Adjustment)

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Mass WastingGeneral term for mass movement of earth material at earth’s surfaceDriving and Resisting ForcesClassificationCauses: “Triggering Events”Prevention / Adjustment

Driving and Resisting Forces*Safety Factor: Resisting/DrivingS.F. >1 = stable slopeS.F.>1 = unstable slope (failure)

Driving Forces: Gravity (mass of material)weight of geologic material (grade of slope)weight of waterweight of structuresweight of vegetation

Important FactorsSteepness of Slope: Greater component of gravityPercent Grade= (Rise/Run)*100 = (elev change/ horizontal)*100

Water: Increases Cohesion (for small amounts)Adds WeightReduces Shear Strength (for larger amounts)

Vegetation:Adds to shear strength (roots)Removes water (transpiration)Provides Protection from direct impact of rainAdds weight, which may be a driving force

Rock Type:Wet clays and poorly cemented rock= low shear strength

What determines Factors?Steepness of Slope:Tectonic Forces (uplift)Slope Modification: nature (rivers), peopleWater: Climate Drainage VegetationRock TypeNatureModification by Humans

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Classification of Mass WastingFlows Slides FallsSubsidenceColluvium (a definition): loose unconsolidated deposit at the foot of slopes (landslide deposits)

Flows (independent motion of particles)Creep: slow downhill motion, J-shaped trees, high dollar damageDebris Flow: moderate to fast1/2 material > sand sizeMud/Earth Flow: moderate to fast1/2 material sand size or smaller

SlidesTranslational: motion parallel to an inclined plane (bedding or foliation)moderate to very fast“rock slides”Rotational: motion on a concave surfaceslow to moderate (fast in some cases)usually in poorly cemented sediments“slump”often a flow at the base

Rockfall

Subsidence

Prediction:Immediate Causes of Mass wastingHeavy RainfallDrainage / Dam failureSteeping of Slopes (River, Road/Houses)Added Weight (Houses, Tanks, etc.)Removal of VegetationEarthquakes

Long term causesSlope Modification (removal of toe)Drainage ModificationRemoval of VegetationWeathering of RockAccumulation of RainProlonged Sesimic Activity

Prevention and AdjustmentIdentify Vulnerable Areas

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Earth Material, Drainage, Steepness of SlopesOrientation of Strata, Rainfall, VegetationModifications: drainage, vegetation, building

Evaluate Vulnerable AreaPlanning / Zoning limit activities in sensitive areas

Modification of the settingSlope: grading, terracingStrengthen Slope: retaining walls, bolts, etc.Drainage: divert water, cover slopesVegetation: increase shear strength

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Groundwater* Part of hydrologic cycle* Water Table / Aquifer* Porosity / Permeability -Flow* Water As A Resource (>50% of drinking water; 22% of all fresh water)* Contamination: Point / Nonpoint Sources

Porosity and Permeability* Porosity: Total volume of rock occupied as pores. Amount of void space in rock* Permeability: Ability of fluid to flow through the rock. Amount of interconnected void space- related to porosity, cementation, compaction* Aquaclude : impermeable layer- aquatard: low permeability layer

Water Table and Aquifer* Water Table: Planar surface between saturated and unsaturated zones- Unsaturated Zone = Vadose Zone* Aquifer: Region below the water table that contains a “useful” or “economic” quantity of groundwater.- Implies a permeable reservoir rock

Flow of Groundwater* Gravitational Flow* Natural Flow rates are slow -water moving through a sponge. 15cm/day is a fast rate* Dependent on hydraulic conductivity, gradient, and area of flow* Restricted and directed by impermeable layers - Artesian well example- Perched water-table example* Pressure gradient: pumping causes a flow upward

Changes in water tableSeasonal Fluctuation: Wet and Dry SeasonsRecharge vs. Output Cone of Depression: pumping causes output faster than recharge. Pump tests are done to determine rate of recharge for wells.Pumping may lead to Salt Water IntrusionCaused by overpumping that draws in denser salt water - due to a change in water table

Water ResourcesInput vs Output - Maintaining a ReservoirOverpumping: result in draw-down of a reservoir, subsidence, and possible destruction of a potential reservoir.Recharge vs Output relationships need to be understood. Groundwater in arid west may be “fossil water” from wetter climate periodsRate of recharge may be slow due to slow rate of flow from recharge areas.

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Groundwater ContaminationPoint Sources: Specific sources of pollutants (such as a leaking storage tank, landfill, manufacturing plant)Nonpoint Sources: General sources of pollutants (such as general urban or agricultural activities)

Types of Contamination* Organic Matterexcessive nutrients - use up oxygenbacteria (fecal coliform) / viruses * Hydrocarbons - Volatile Organic CompoundsConstituents of Gasoline (benzene, toulene, ethylene) This will break down with time* Chlorinated Organic CompoundsDDT, PCBs (polychlorinated biphenyls), TCE (dry cleaning fluid): Do not break down naturally* Heavy Metals: Lead, Mercury, Cadmium

Site EvaluationPast HistoryGeology : permeability, types and orientation of strataHydology: rate and direction of flowContaminants - toxicity, rate of breakdownTreatment Process: Passive: Allow for natural breakdownActive: Onsite of Offsite

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Energy ResourcesRenewable vs NonrenewableResource vs ReserveSupply?HydrocarbonsOil (Petroleum) and Natural GasCoal

Resources and ReservesResources: naturally occurring concentration of material in a form that can be economically extracted or may be economic in the futureReserves: resources that can be legally and economically extracted at the time of evaluation.

Renewable and Nonrenewable ResourcesDepends on time of renewalgeologic time vs. human timeRenewable on human time scaleExamples: some water, some vegetationNonrenewable on human time scaleExamples: fossil fuels, ecosystems, minerals

Impact of Resource ExtractionImpacts we see Mining - open pits, acid drainageDrilling - spills, drilling fluidsPollution form processing / use of resourcesImpacts we do not seeResources from around the world73% of tin imported from other countries (Brazil, Bolivia, China, etc.)90%-100% of Aluminum imported

Energy ResourcesUnited States represents about 5% of world population; we consume about 25% of world energy production90% of energy from fossil fuels: oil, natural gas, coalHydrocarbons: hydrogen and carbon compounds (petroleum products and natural gas)

Fossil FuelsFormation of Oil and GasAccumulation of Organisms (rich in carbon)ocean or swamp type environment - low latitudesRapid Burial in Low Oxygen EnvironmentOtherwise H20 and C02 producedHeat and Time: 50-100°C (120°F-210°F); 10,000 or more years.Low = heavy hydrocarbons: tarMedium= light hydrocarbons: oil

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High= natural gas (too high destroys hydrocarbons)Migration of hydrocarbons from source rock to host rock.Host= porous and permeable (a reservoir)Trapping of Oil and GasAnticline Traps, Fault Trap, Stratigraphic TrapsRequires impermeable layer above

Supply of Hydrocarbons* World Resources of Oil: 1500-3000 billion barrels (Reserves: 800-1000 billion barrels)Use 25-30 billion barrels per year* United States Resources: 100-500? Billion barrels (Reserves: 30-50 billion barrelsUse 6-10 billion barrels per year* Natural GasWorld Reserves: 4200 trillion cubic feet, use 25 trillion per yearUS Reserves: 200 trillion cubic feet, use 5 trillion per yearOther FactorsGlobal demand is rising about 2% per yearAbout 1/2 of US oil is importedUS has about 15% of world oil, uses about 30% of what is produced (annually)New Finds: All of Alaska Oil Field: 10 billion barrels; Caspian Sea (Russia, Kazakstan): 50-150 billion barrels; Most giant fields (>0.5 billion barrels) have been found.Bottom Line* 25-100 years of conventional oil production remains* 50-150 years of conventional natural gas production remains (less with growth)* 80% of oil produced today flows from wells found before 1973 (most are declining)* A few countries control most of the hydrocarbon resources: Persian Gulf region

Coal - Another Fossil Fuel* Accounts for about 20% of US energy* Formation: land plants buried in a low oxygen (anerobic) environment. Enhanced by sea level cycles* Requires burial, compaction, and time* Rank (based on % moisture, volatiles, carbon): Peat, Lignite, Bituminous, Anthracite* Resources are well known (because coal exists at shallow depths, <2km)* 10 trillion tons - 30% in the US* World Supply equivalent to 62,000 billion barrels of oil* Presently used for 20-25% of US energy* Could satisfy US for 200+ years

Drawback for Coal* Pollution: Ash, Carbon Dioxide/Monoxide, Sulfur from burning. Global Warming and Acid Rain Scrubbers and filters can remove much of the toxic material (but not Carbon Dioxide).* Surface Mining Impact: Stripped from thin beds.- Reclamation of the land is routinely performed* Not as portable as oil and gas- liquefy the coal?

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Energy Sources of the Future?Conventional Oil and Gas will be gone

Considerations: - Need / Conservation, Population Growth?- Sustainability: Renewable Resources?- Impacts: Global Warming, Pollution,

Alternative Energy SourcesAlternative Hydrocarbons: Oil Shale, Tar SandsNuclear: Uranium miningBiomass: burning organic materialHydroelectric: dam systems, large to smallSolar: Passive, Active, WindGeothermal: using earth’s internal heatHydrogen Fuel CellsOthers: Tides, Ocean thermal systems

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ATMOSPHERIC CHANGE* Atmosphere Structure and Content* Observations of content and change* Hypotheses of climate change* Implications for Society

Atmosphere Structure and ContentTroposphere: Weather Sphere, 80% of total mass (much of it water vapor): 0-12km* Stratosphere: 19% of total mass, 12-50 km* Mesosphere: 50-90 km* Thermosphere: 90-120km* Dry Air in Troposphere: - 78% N2, 21% O2, 1% Ar, <0.036 CO2, 0.00005% O3 (ozone)

Observations of content and changeNatural Change in Temperature (over geologic time): 8+ °C* Temperature Change since the Industrial Revolution: 0.5-1°C* Natural Fluctuation in C02 and other greenhouse gases (from bubbles in ice)* Recent Change in CO2: ice and direct observations

Hypotheses of climate changeHuman-related increases in certain gases have caused an “unnatural” warming of the atmosphere.* Increases in CO2, CH4, and other gases increase the ability of the troposphere to retain infrared heat - The Greenhouse Effect

* Ultraviolet radiation from the sun penetrates the troposphere and is absorbed by the earth. This heat is given off by the earth in the form of infrared radiation. Greenhouse gases absorb this radiation.

* Therefore emission of greenhouse gases is causing a warming of earth’s atmosphere.

Implications for SocietyEnergy Sources: Should CO2 producing energy sources be restricted, prohibited?- Implication for Carbon-Based Fuels: Oil, Gas, Coal, Biological-based fuels* Warming Climate: - Severe Weather: crop loss, coastal erosion, loss of life and property- Rising Sea Level: 20cm to 1m next century?Melting of West Antarctic ice sheet may produce a 5m rise.

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Ozone Depletion - how does this differ from global warming?* Ozone is vital to life, shields ultraviolet radiation from the sun* O3 - 0.00005% of atmosphere- concentrated in stratosphere (0.001%)- 4mm thick if concentrated on earth’s surface* Formation in stratosphere:- Sun's energy (UV radiation) causes O2 - breaks into O and O- O combines with O2 to make O3

Ozone Depletion* Compounds such as chlorofluorocarbons (CFCs) cause chlorine to be released in the stratosphere. Methyl Bromide is similar* CFC rises to stratosphere. Solar radiation causes a break-up of CFC to release chlorine (Cl)* Cl reacts with O3 to produce O2 and ClO* Cl breaks out of ClO and causes repeated destruction of O3. As many as 100,000 molecules of O3 destroyed by one Cl atom

Ozone Holes and CFC policy* 1985 - Antarctic ozone level decreased by 50% since 1970* Ice-mediated reactions in polar regions causes accelerated chlorine-induced ozone break down.* Impacts: solar radiation related to skin cancer, immune system break down, reduction of crop yields* Montreal Protocol - a ban on CFCs. Agreement reached in late 1980s and early 1990s. Over 150 countries have signed onto this protocol.

Differences of Ozone Depletion and Global Warming* Global warming due to gases that accumulate in the troposphere and absorb infrared radiation. The main gases are CO2 and CH4 (but ozone can also absorb heat and can be considered a greenhouse gas).* Ozone depletion results from breakdown of O3 in stratosphere. This allows more of sun’s ultraviolet (UV) radiation to reach the earth’s surface

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Study Guides

These may apply to your instructor’s course. You will be notified if all or any of these apply to the tests in your specific environmental geology class.

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Geology 10, Environmental Geology Study Guide for Test #1The test will consist of multiple choice and short essay questions.The following provides an overview of topics covered in this first portion of the course.

Fundamental ConceptsThe Scientific Method: What are the basic steps? How does a hypothesis differ from a theory? Describe the advantages of using multiple working hypotheses.Human Population (Exponential Growth): What is the World population? What is the US population. Describe how US resource use compares to its percentage of World population.Systems: How is the Earth an Open System? How is it a Closed System? What is residence time?

Geologic TimeAbsolute vs. Relative Time, Principles of Original Horizontal, Superposition, Crosscutting Relationships: Be able to use the principles to provide an ordered sequence, from oldest to youngest. Principles of a radioactive decay system (e.g., Carbon 14 system). Explain how Parent material, Daughter Material, and Half-Life are related to radioactive decay.

RocksDescribe the difference between a rock and a mineral. Give an example of each. Provide definitions of igneous, sedimentary, and metamorphic rock. Which rock type covers most of the earth surface? What type of rock makes up the majority of the continental crust? Which type of rock makes up the majority of the earth’s oceanic crust?

Plate Tectonics OverviewDefine the theory of plate tectonics. Describe the three types of plate boundaries. Describe the type of plate motion found at each boundary. Draw a figure showing the oceanic and continental crust, the lithosphere, the mantle, and the core (inner and outer core combined). Describe the lithosphere. Be able to determine the rate of plate motion knowing the age of displaced rock and the distance of displacement (rate=distance/time)

Hazards: How does our discussion of population relate to geologic hazards? What do we mean by hazard? Do these hazards (such as earthquakes) serve any useful purpose?

You are responsible for material covered in In-Class Activities #1, #2, #3, and #4

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Geology 10, Environmental Geology Study Guide for Test #2The exam will consist of multiple choice and short essay questions. The following provides an overview of topics covered in this portion of the course.EarthquakesTerms: fault and fault types (reverse, thrust, normal, strike-slip), focus (or hypocenter), epicenter, magnitude, intensity, seismic waves, seismograph, seismogram, fault. Concepts: Describe the Elastic Rebound Theory. How is it related to stress and fault motion? What type of fault is the result of compressive stress (squeezing), of tension (stretching), of shearing stress? Describe (in general terms) how a seismograph works. Discuss how magnitude is measured. What is measured? How much more energy is released for each unit of magnitude? What is the basis of the intensity scale? When is it useful? Describe the hazardous effects of earthquakes. How are earth materials related to the damage done by an earthquake? What types of earth materials are the most susceptible to shaking? Where do most earthquakes occur? Is it possible to earthquakes away from plate boundaries? What are common methods of prediction: seismic gap, foreshocks, ground movement (stress measurements), magnetic fields, P-wave/Surface-wave time delay? How accurate (days, years, etc.) are the methods.What causes Tsunamis? How fast do tsunami waves travel? How might tsunamis be related to landslides or volcanic eruptions?

Rivers and Flooding:Terms: tributary, trunk, delta, drainage basin, drainage divide, channel, gradient, meander, point bar, stream bank, levee, floodplain, profile, discharge, headward erosion, dissolved load, suspended load, and bed load.Concepts: Be able to evaluate a meandering stream and predict points of erosion and deposition. How do point bars and cut banks differ? How is change in stream profile related to headward erosion. How does bank stabilization relate to the energy of water and flooding downstream? Be able to draw a simple hydrograph (discharge vs. time) showing a flood and label the axes. Understand the concept of flood recurrence. Does a 100-year flood happen every 100 years? How can a 50-year flood occur two years in a row? What is the probability of a 50-year flood occurring any given year? How often does one expect bank-full discharge from a stream? Discuss methods of flood prevention. What is channelization? What are some disadvantages of these methods? Discuss methods of flood preparation and adjustment.

Coastal Processes and HazardsTerms: Longshore Transport, Spit, Jetties, Breakwater, Seawall, Beach NourishmentConcepts: How does longshore transport facilitate transport of sediment? What are sources of sediment input to the longshore current system? Where are points of sediment output? How do dams, jetties, and other human intervention alter longshore transport and beach sediment?

Mass Wasting and SubsidenceTerms: Flows, Creep, Slides, Slump, Fall, Driving Force, Resisting Force, Safety Factor, Sedimentary Rock: Sandstone, Mudstone, Grade, J-shaped trees.Concepts: Discuss the different types of mass wasting: flows, slides, subsidenceHow do earth materials influence mass wasting? What is the difference between sandstone, and mudstone. Why is clay content important when evaluating the potential for mass wasting? Discuss the role of bedding planes, fractures, and strength of rock type in mass wasting.How do topography, water content, and vegetation influence mass wasting? How do removal of vegetation or road building contribute to mass wasting? Discuss methods used to mitigate mass wasting: drainage control, slope modification, vegetation, ground cover, retaining walls, bolts, etc.

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Geology 10, Environmental GeologyStudy Guide for Final Exam, Scantron sheets are required

The exam will consist of about 15-20 multiple choice (2 pts each) questions and 4 to 6 short-answer questions (each with multiple parts). Approximately one third will be material covered since the last exam. The other portion will be a review of previous material. Some questions will be taken from previous exams.You may use a sheet of your own notes (both sides of 8.5”x11” paper) during the exam. No photocopied material is allowed. Computer printouts are acceptable, but duplicate printouts are not allowed.Material from Tests 1-2 (refer to previous tests and study guides)

New Material:

Groundwater / Groundwater and soil contaminationTerms: reservoirs and residence time, permeability, porosity, water table, aquifer, recharge, perched water table, saturated zone, unsaturated zone, confined aquifer, unconfined aquifer, point source of pollution, non-point source of pollution, remediation, volatile organic compounds, chlorinated organic compounds. Concepts: Be able to describe the characteristics of an aquifer. Discuss the difference between a confined (closed) aquifer and an unconfined (open) aquifer. Provide average rates of groundwater flow. Describe how impermeable layers influence the flow of groundwater. What percentage of the US uses groundwater as a primary source of drinking water? What are the consequences when groundwater withdrawal exceeds natural inflow (recharge)? What is meant by subsidence due to groundwater removal? What are some of the long term impacts of overpumping? What solutions are available to protect groundwater resources? What are examples of point and nonpoint sources of pollution? Describe some common types of contamination. How do differences in the type of contaminant influence the method of cleanup (volatile organic compounds vs. chlorinated organic compounds)? What are some common remediation (cleanup) techniques?

Energy ResourcesTerms: hydrocarbons, fossil fuels, hydrocarbon trap, source and host rock, anticline, syncline, oil shale, coal, passive and active solar systems, biomass, geothermal.Concepts: Describe the relationship between the U.S. population relative the world population and our percentage of energy use. Describe the process of hydrocarbon formation (oil and gas) and accumulation (into usable reservoirs). At present rates of consumption, about how long will it take to deplete hydrocarbon (excluding oil shale and coal) resources? Will new finds the size of the Alaska oil fields substantially extend these resources? Explain. What are some of the problems with extracting hydrocarbons from oil shale? How extensive are coal resources within the U.S? How far in the future could this resource supply the U.S. energy demand? What are some of the problems associated with the use of coal? Describe an alternative energy source. What are some of the advantages and limitations of using this resource? Atmospheric ChangeTerms : Troposphere, stratosphere, ozone, CFC (chloroflourocarbon), ozone hole, glacial ages (ice ages), greenhouse effect, greenhouse gases.Concepts: The composition of dry air. Describe the natural formation of ozone. Describe how CFCs cause the destruction of ozone. What are some of the adverse effects of ozone depletion? Describe how scientists make indirect measurements of past climates. What are some probable causes of long term (million to billion years) climate changes? Describe what is meant by the

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greenhouse effect? What gasses are considered greenhouse gases? How have atmospheric CO2 levels changes over the last several decades? What are some human-related sources of these gases? What has been the general trend of global temperature changes over the past 100,000 years. What are some ideas concerning the relationship of human activity and these changes? Why is it so difficult to “prove” that we (people) are causing global warming? Discuss how this knowledge of greenhouse gases may influences our choices of future energy sources.

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