South Lake TahoeA field Study

By: Wendy Vazquez

Table of Contents

• Formation of the basin • Landscaping of Lake Tahoe• Igneous-Basalt Rock • Granite Rocks • Metamorphic Rocks • Manzanita Arctostaphylus• Snow plant• Reference

Lake Tahoe Basin The basin is bounded by the Sierra Nevada to the west and the Carson Range to the east. Lake Tahoe basin was formed by a block faulting 2 to 3 million years ago(Gould,2012). The uplifted block created the Carson Range and the Sierra Nevada. Down dropped blocks created the Lake Tahoe Basin in between high peeks.

Modern Lake Tahoe

Lake Tahoe was shaped and landscaped by glaciers during the ice age about a million years ago (Antonucci,2012). The lake is drained by the Truckee River. During the Pleistocene there were many glacial periods in the Sierra Nevada (Resendes,2012). The weight of the glaciers would cause them to go down hill and picking up sediments, rock and boulders as they went down. Glacial moraine deposits have created some of the most striking shoreline features along the west side of the lake including emerald bay and Fallen Leaf Lake( Michaelsen).

Igneous- Basalt Igneous basalt is mostly common in Earth’s crust and it also makes up most of the oceans floor. This rock is made by dark colored minerals pyroxene and olivine(Basalt). This rock also contains mineral crystals that are very hard to see because the quick cooling of the rock prevents large crystals from forming. Basalt forms when lava reaches the earths surface at a volcano or mid ocean ridge it cools quickly within a few days or weeks and forming a solid rock (Basalt).

Granite Rocks Granite is the best know igneous rock. Granite is light colored with grains large enough to be visible. This rock forms from the slow crystallization of magma below earths surface. The mineral composition usually gives granite a red, pink, gray or white color with dark mineral grains that are visible throughout the rock( Granite,2005).

Metamorphic Rock The formation of the metamorphic rock was that lava plumes reached a block of sedimentary under the shallow sea. Tops of the lava plumes pushed through the rock leaving outcrops of altered sedimentary rock called metamorphic rock (Hill). This is made up of fine grained mica their surface of phyllite is typically lustrous and sometimes wrinkled.

Manzanita Arctostaphylus The Manzanita Actostaphylus have small white flowers. This species has a hard attractive wood. There are about 106 different types of Manzanita species. Having a rich fossil record is considered to be of Miocene origin about 15 million years with radiation of the genus occurring 1.5 million years ago during the Pleistocene (Schaefer).

Snow plant Snow plant is a red, fleshy, glandular –hairy saprophyte lacking chlorophyll with simple stems either solitary growing up to 20 inches tall(Sarcodes). It has evolved with angiosperms, flowering plants with enclosed seeds. This plant did not arrive near the Lake Tahoe are until other plants michorrhizae that it could be able to gain nutrients from(Monroe & Wicander) . This plant grows when snow begins to

melt.

Reference Antonucci, D. C. (n.d.). Lake Tahoe Fast Facts . In Tahoe Fund. Retrieved July 19, 2013, from

http://www.tahoefund.org/about-tahoe/recreational-paradise/

Basalt Rock (n.d.). In Window To The Universe. Retrieved August 1, 2013, from http://www.windows2universe.org/earth/geology/ig_basalt.html

Gould, M. (2012, December 13). Geography & History Overview. In Geography the National Map. Retrieved July 18, 2013, from http://tahoe.usgs.gov/geography.html

Granite (2005). In Geosciene News and Information . Retrieved August 2, 2013, from http://geology.com/rocks/granite.shtml

Hill, M. (n.d.). The Formation of Lake Tahoe and Filling the Basin . In Geology . Retrieved August 1, 2013, from http://eh2o.saic.com/tiimsWebsite/Content/BasinTopics/geology/default.asp

Michaelsen, J. (n.d.). In Sierra Nevada Physical Geography . Retrieved August 2, 2013, from http://www.geog.ucsb.edu/~joel/g148_f09/readings/sierra_nevada/sierra_nevada.html

Monroe & Wicander, R.(2009).The Changing Earth: Exploring geology and evolution. Belmont, CA:Brooks/Cale, Cengage Learning.

Resendes, M. (2012). Geology Of The Sierra Nevada . In Central Sierra Historical Society. Retrieved July 27, 2013, from http://www.sierrahistorical.org/geology-sierra-nevadas

Sanguinea, S. (n.d.). Snow Plant . In Sarcodes Sanguinea . Retrieved July 19, 2013, from http://www.calflora.net/bloomingplants/snowplant.html

Schaefer, B. (n.d.). Arctostaphylus . In Biogeography of Ravens Manzanita . Retrieved August 2, 2013