california geology magazine july 1990

8/7/2019 California Geology Magazine July 1990

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July 1990IVolume 43/Numbe. 7CGeeA 43 (7) 145 168 (1990)

For further information about the conference. conlaClthe Earlhquake EngineeringResean:h lnstlture. 6431 Fairmonl Avenue.Suile 7. EI Cerrilo. California 94530-3624.USA (415) 525-3668.

The conference will provide an imernalional multidisciplinary forum for discussionand disseminalion of recem advances perlinent 10 the reduetion of losses from naturaldisasrers worldwide. All papers ""i ll bepublished in a proceedings volume. Toursof aClive earrhquake faulrs. eanhquakeengineering researeh facililies. and localurban planning organiutions are planned10 complement olher conference aClivities.

In This Issue IDREDGING AND PLACER MINING CONFERENCE.. . 146FOURTH INTERNATIONAL CONFERENCE. SEISMIC ZONATION 146MAPS: THE EARTH ON CANVAS , . . . . . . . . . , . . . . . . . 147GREENWICH MEAN TIME.. .. 157MINE SAFETY. 1893 159EARTHQUAKE SAFETY AWARD.. , . . . . . . . , 160TRiViA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,.160ROCK CROSSWORD PUZZLE. , . . . . . . . . . . . . . . . . . . . . . ..161ENGINEERING GEOLOGY FOR THE 90'S.. . .. . 162ANSWERS TO ROCK CROSSWORD PUZZLE .. 162BOOK REVIEWS . . . . . . . . . . . . . . . . . . 163MAIL ORDER FORM . 165CALIFORNIA GEOLOGY SUBSCRIPTION FORM 166DMG RELEASES , .. , . . . . . . . . . . . . 167DMG OFR 895, INDEX OF GEOLOGIC REPORTS - SPECIALSTUDIES ZONES... . 167DMG OFR 8916, SUMMARY REPORT: FAULT EVALUATION PROGRAM 168DMG OFR 90-5, GEOLOGIC MAP- SOUTH HALF EAGLE LAKE QUAD , 168

Cover: Oblique fOised lopog.opliic mop 01 the cenl.ol Son F.oncisco 80y o'eo. Son Francisco 80y is 0mid 10 late PI ..slocene Itructurol trougfWilhin the Cooltol Rongel. Neorly 70 percent of the Boy isr.hOtiowlf thon 12 feet. Over 2 million yeors ogo this e ..'...os ebove leO level end.th.ough loldingond loulhng, this 0"0 slowly 'onk Q ~ t h e SlO engulledihev:alIif."Th,oughout the enwing lime toobout 10,000 yeors ago Ihe Boy wos effected by PI.. lIocene glaciotion: olternOlely rising an'd lowering,n response ta e growth and m.lting 01 continentol glociers. During periods of ext . . me low seo levi!,riv.rs cut dKinnels inlo Ihe bedrock floor 01 the 80Y10 (I depth 0/ neorly 400 '&fit b.low the p.osent1.0 level. Since the end 01 the Pleistocene glociotion, riversediments were deposited neony ho.i10nt o l l ~ o n Ihe Boy 1100" Sediments on the cent.ol portion ollhe oor-hove been meosured ot 250 leetdeep. An ortide oboul lhe hiltoricol signi!iconce 01 mops. and how mopl0 . . mode ond uled storts onpoge 147. Drawn by TOll Rho A/pho.

The Fourth International Conference on"Seismic Zonal ion for Safer Constructionand Reduclion of Lifc and Property Lossesfrom FUlUre Earthquakes" will be held atStanford Universily in the San FranciscoBay region. Augusl 2610 28.1991. Theconference. sponsored by lhe EarthquakeEngineering Research Inslilute. will providea SI8teof-lhe-art assessment of lhe advancesin seismic 'Zonalion integrating earth sciences.engineering. planning. social sciences. andpublic poliey. The confl."rl."nce will emphasizeresults perlinem 10 disasler mlligalion onlocal . regional. and national scales al localions throughoulthe United Slall."S and theworld.

Dredging and PlacerMining ConferenceThe Nevada In;;lilule of Technolog)' willhold the 81h Conference on Dredging and

Placer Minmg on October 29-31. 1990. inSparks. Nevada.For further informal ion conraCl:Dr. Yung Sam KimConference DireClOrNevada lnslilule of TechnologyP.O. Box 8894. Campus StalionReno. NV 89507Tel. (702) 331-0601

Fourth International ConferenceSeismic Zonation

Loui$8 Hu


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MAPS:The Earth on CanvasBy

EVElYN M. VANDENDOLDER, EditorArizona Geological Survey

Tucson, Arizona

.. . Fi;ure I. Cor1ogrophic in'I"'....nls rang' in soplli,ricolion from the compou, i n ~ e l l t e d durillgthe 11th or 12th cenlury, 10 ~ o m p u l . r ')'Ilems thatcan increos. the ,peed, o c ~ u r o ~ y , olld qualityofall mop mo.;ng effort!. Drawing by P.te, F.Corroo, AArOnO G.ologicol Survey.

Thi, Clrtkle g j ~ " Cln C l b b r e ~ i o l e d hi,1OI'Y of~ C l r 1 o g r o p h y _ the Clr1 of mClp moking; expklin,I ~ o l . , coo.dinClt. ') 'Item" ond projeclion,;iI1""lI'Ol.s how remot.-sensing techniques Clidmop moking; describes vatlou1 lplKiClliud mopsond how they ore used; ond ~ ' I s sourCei fo-robtoining ColifomiCl mops.The following WOI originCll1y publilhed in theJuly 1987 iuue of F i e l d n o ~ .. ~ 17, no. 4,published by the Arirono BurellU of G.ology Clnd

Mineral Technology. II is reprinted her. bypermission of the ClUthor. S i n ~ e the rime il WCl>publish.d, the nom. of the mClgorin, hClI bunchClnged 10 AArono Geology, ond the nom. ofthe 1101. og.ncr Well chong,d 10 the ArironoGeologicol Su .....y, locoted ot 845 N. Porlt Ave"1100, Tuclon,A185719. The cont.1l1 of Ih ,originol ornel. wOI modifi.d ond odopt.d forinformorion oboul Colifornio.. editor.

INTRODUCTION

Amelia Earharl. the plucky aviatorwhose 1937 round-the-world flightattempt ended in disaster. may have beenthe victim of a mapmaker's mistake. Earhart's flight plan gave the wrong coordinates for Howland Island. the 2-mile-longsandbar in the South Pacific that she andnavigator Fred Noonan were trying toreach when they vanished. The faultyflight plan. which was based on inaccurate government charts. put Howland Is-land 7 miles to the northwest of its actuallocation. Earhart's flight plan listedthe coordinates for the tiny island as

latitude (Iat) 0"49'N.. longitude (long)17643'W.. whereas the actual coordinates are lat 048' N.. long 17638' W.(Barker. 1986). Some investigators whoresearched the possible causes for Earhart's disappearance believed that she andNoonan were on course and would havereached Howland Island if they had beengiven the correct coordinates. The firstchart to list accurate coordinates was published 4 to 5 months after they vanished.It is therefore Ijkely that the mappingmistake was discovered during the searchfor Earhart.Earhart's story illustrates the importance of accuracy in maps and translates aseemingly inconsequential error on paperinto the language of human tragedy.Accurate. dctailed maps have enabledhumans to chart not only their courses

across vast oceans. but also the progressof their civilizations.HISTORY OF MAP MAKING

Maps are as old as human culture. Thedetail and accuracy of mapmaking effortSha\


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pans of Europe. Africa, and Asia. wasthe first to IOclude parallels and meridians. The early Greeks also defined thepoles. equator. and tropics and developedsevel"'J.l projections that are still used today.

Medieval cartographers. seeking amore simplistic view of the world to mirror their religious beliefs. chose moresymmetrical, "divinely perfect" outlinesfor Europe, Africa. and Asia l"'olther thanthe more accurate irregular coastlines ofearlier maps. In the late 13th century.oowC\'er. the use of the compass burgeoned. as did the production of highlyaccurate maps known as portolan charts.which were used with minor modifications for more than three centuries. Portolan charts were based on systematiccompass surveys. Most charts included 16or 32 compass roses with radiating rhumblines (lines that show compass direction).a design sometimes used on current mapsas decoration (Raisz. 1962).The discovery of the Americas effecteda renaissance in carlOgraphy. As thenumber of trade routes increased. so didthe need for more detailed maps. Newdiscoveries from explorations modifiedhumans' view of the world. The first mapto include America. published in 1500.showed it as part of Asia (Raisl. 1962). Itwas not until after Magellan's voyagefrom 1519 to 1522 that maps accuratelydepicted the immensity of the Pacific

Ocean. The in,'ention of the engravingand printing processes during this periodenabled wider and more timely distribution of new maps. The highest qualitymaps produced during the late 16th and17th centuries weTe compiled by DUlChand Flemish map making masters. suchas Mercator. Ortelius. and Janszoon(Rain. 1962).The 18th century, known as the Age ofReason, brought a concomitant age ofmap accuracy. Instruments to measurelatitude and longitude became more s0 -phisticated. Triangulalion and topo

graphic mapping of France during Ihistime spurred interest in similar nationalsurveys during the following century(Raisz. 1962). Cartographers of the 19thcentury also diversified and specializedtheir products. creating geologic. economic. and transportation maps. amongothers. Wilh the founding of the U.S.Geological Survey (USGS) in 1879.systematic mapping of the United Statesbecame an organized effort.The advent of remote-sensing techniques. such as aerial photography and

satellite imagery. enables cartogrolphersto cre:lIe a "bml's-cye" \'iew of Ihe ,",orldand ItS fe:ltures. Digital scanning s y ~ t e m s:lnd 1a.\Cr ploHers have dramatically increased the accuracy and detail of modernmaps (Figure I). Technological advancesand increasingly sophisticated instruments continue to cnh:lnce the qualityand accuracy of human aHempts atsketching the face of Earth.SCALE

Scale defines the relationship betweena distance shown on a map and the corresponding aclual distance on the ground.Scale may be expressed in three ways(Zumberge and Rutford. 1983):(I ) As a graph, line. or bar divided intounits that represent ground distances.(2) In words that state the relationship between map diSlance and ground distance:for example. "one inch equals one mile"mellns Ihat I inch on the map corresponds to I mile on the ground.(3) As a fraction or fixed ratio betweenlinear measurements on the map (the nu-merator) and corresponc:!ing distances onthe ground (the denominator). For example. a scale of . , _ ~ or 1:63.360 meansthat I unit of measurement on the map(I inch) represents 63.360 of the s a m ~units on the ground. In this example, Iinch on the map corresponds to I mile onthe ground II inch (map) - 63.360inches (ground) : I l l 5.280 feet (ground) =I mile (ground)J. The firsl number (mapdistance) given in the rillio is always l:the second number (ground distance)varies. but the l a r g ~ r the second number.the smaflu the scale.Many areas have been mapped severaltimes. but at different scales. One shouldchoose a map with a scale specific to itsintended use. For instance. a large-scalemap shows more detail. but less area:therefore. an urban planner might choosea 1:600-sca1e mllp that shows power andwateT lines. house lots. and streets. Asmall-scale map shows less detail. but encompasses a wider area. A geologist in-

terested in the general geologic history ofCalifornia might choose a 1:750.000scale geologic map of the state that showsmajor rock formations and geologicfeatures.Large-scale topographic maps (see section titled "Types of Maps") of 1:24.000show natural and man-made features.such as important buildings. campgrounds. caves. ski lifts. watermills.bridges. and private roads. Intermediatescale IOpographic maps of I:50.000 and1:100,000 usually omit these features.

Small-scale topographic maps ofI:250.000 and smaller (such as scaleswith a larger denominator) show only ma-jor features like national and state parks.military reservations. airports. majorroads. and l"'olilroads (U.S. GeologicalSurvey. 198Ib).

COORDINATE SYSTEMSAccurately locating oneself on a map inthe wilderness is not easy. Evtr since thefirst map was compiled. cartographershave searched for an accurate system tolocate points on the globe. Some mapusers, such as navigators. need a meansto track their progress across oceans:others. such as land owners and govtrnment officials. need a method to establishproperty lines: still olhers. such as geologists. need a way to identify localities

of outcrops and separate rock units sothai future researchers can find andstudy them.In the United States. three coordinatesyslems are generally used: (I ) geo

gl"'olphic coordinates (latitude and longilude): (2) Public Land Survey (PLS). alsocalled the "Land Ornce Grid" or "township and r4nge": and (3) Universal Trans~ - e r s e Mercator (UTM) grid. Each ofthese systems is explained in the following sections.latitude and longitvdeCartographers have arbitrarily dividedthe Earlh's surface into a system of referenee coordinates termed latitude and Iongitude based on a series of imaginarylines. called parallels and meridians.respectively. drawn on the surface.Ifone imagines Earth as a globe withan axis Ihrough the North and Southpoles, meridians of longitude would becircles around Ihe globe that pass throughboth poles. A meridian is labeled according to its distance. measured in degrees.east or west of the zero meridian, which

was established in 1884 by internationalagreement as the meridian that passesthrough Greenwich. England. near lon-don. Before this time, many countriesused meridians that passed through theirown capital cities as the OD meridian fortheir own maps (Chamberlin, 1950). Thezero meridian is also called the Greenwich meridian or prime meridian. Be-cause the globe encompasses 360". the180" west meridian (long 180" W.) andthe 180" easl meridian (long 180" E.) ~ P resent the same imaginary line known asthe International Date Line. Although

'"CALifORI'IIA GEOlOGY


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75 ' 100'12.5' 125' 100' 75 ' 5.0'2 0 . ' ~__(

\ rr

\ \ \\

I

'00'

0'

O

5.0' 7.5'

5W

'oow

Figvre 2, Mognlttic declinotion, olso known os composs variation, is thlt ongle between True (geographic) north and The direcTion given by the m o g n e ~ c composs[mognetic north), Magnetic declinaTion 01 the beginning 011980 is indicaled in thisligvre by isogonic line., or lines of eqval declination, Valves olong lap ofchart reler to dashed lines. Valves along sides and bottom refer to solid line>. Solid lines indicOle lhe nvmber of degrees between magnetic north and lrue north,with mognetic north shown east of true north at locotions that are west 01 the O'line [labeled at the bottom of Ihe figure), ond west 01 trve north eost of 0" line.Dashed lines indicate change, in minutes per year, in directIon of magnetic north, with change TO more eastward direction eOSI of 0" line [Iobel&d ollop of~ g u r e ) , and chonge 10 mOre westward direcTion west of 0" IlIle. From Fabiano and Peddie, 1980.

this line mostly follows the 180" meridian. there is some variation to preventsepar


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zOCwm

SAN BERNARDtNO BASE LINE

Township-range divisions arc bascd ona grid of perpendicular lines. Boundarylines that rUIl cast to west arc cal ledlownship lines: those than run north 10south arc called range lines. Instead ofth e equator and zero meridian. referenceIi nes for township designations arc specific latitudinal and longitudinal linescal led the base l ine and principal meridian. respectively (Zumberge and Rutford.1983). A township is located by giving itsposition north or south of the base linean d cast or west of the principal meridian. Th e notalion "'I'. 4 S.. R. 2 W .. indicates township four south. range twowest. Many base l ines and principal meridians are used in the United States. sotownship and range coordinales arc nevcrvery large.

In California. townships arc measuredfrom the Humboldt base l ine and meridian. the Mounl Diablo base l ine and meridian, and the San Bernardino base lineand meridian (Figure 3). For example.the Division of Mines and Geology l:tublications building in Sacramento is locatedat township 9 north (T. 9 N.) of theMount Diablo base line. and range 5 easl(R. 5 E.) of the Mount Diablo meridian.

figure 3. Principal California meridians and baselines, an d the areas where they are used. Datesindkate when the base line' an d principal meridion, were adapted by the U.S. Deportment of theInterior.

.......... ,_ ...

..............,.,. ',,',=,7"'1


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Figure 4. Townlhip and range 101M! divis;ons used ill the Uniled Stole. and insome porn 01 Canoda. From ZlImbe'ge ond Rvtford, 1983.

:..

u


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Figur.. 5. Proj..,lion 01 Ill .. globe onto th,.... ,uria,..., (0) ,egular'ylindrkal(suMa,.., tau,h alongIlquolo,j; (b) I,on,vers..


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b

(Zumberge and Rutford. 1983). Colorv a r i a t i o n ~ result from differences inwgetatlon. soil. moisture. and rocktypes. False-color images cre:lled byE:trth Resource Technology Satellites(comlllonly called Landsat) arc byproducts of the U.S. space progrJlll. EachL;lndsat salellite circles the globe 14time.'> a day. s c a n ~ a particular area ofEarth more lhan 40 times a year. and creales images. each of which covers 115square miles(U.S. Geological Survey.198Iil). Thc frequency and amount ofeo\'Crtlge make satellite imagery esp.:cially useful in studying Earth's surface.Satellite image.s, however. cannot showthe detail that aerial photographs can be-cause they are taken farther from E : l T t h ' ~surface and thus. at a slllalier scale.

TYPES OF MAPSA map b a graphic representation ofpart of E:lrth's surface. Some types. suchas road maps. show the distribution of

f e a l u r e ~ and manmade structures in twodimensional form. Other lypeS. ~ u c h astopographic maps. illustrate the threed i l l 1 e n ~ i o n a l nature of Earth'.'> fealures ona t w o - d i m e n ~ i o n a l surface. Bccause geologic structures are three-dimensional.the l'llter type of map is more useful 10geologist.'>.

Figurll 6. SlllllCllld mop projiK'~ 1 ~ ~ ~ ~ lions: (0) MerColor (regulor cylindricol); (b) Tronsvene M"'rcolor ( I r o n ~ v e r s ecylindricol); (c) Obliqve Mercotor (obliqvecylindricol); (dl Simple Conic (regvlor con'c);

(e) Stereogrophic (plonor or ozimvthol, polor o ~ p e c l ) ; ( Or1hogrophic (plonor Or ozimvthol, obliqve ospect); ond (g) AzimutholE q u , d i ~ t o n t (plonor or oz,mulhol. ",quolo,;ol oo.pe


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FIgure 70. Portion 01 the 15minute U.S. Geolog,col Survey Milford, Colilornio topographic quadranglemop (1:62,500 scolel. A geolog'c mop 01 the .ome oreO '0 ,h's figure i5 shown io Figure 7b on Ihe n e ~ 1poge. The oreo ,n Ihi. mop ,ndudes 0 POrtlOO ollhe Diomond Mounloin" a few mile, 5Oulhe051 ofHoney Lake, Lonen County. Geologis15 use bose mops like Ihis for moppIng geologic feolure,.

There arc basically four t y p e ~ of mapS:planimetric. lopogmphic. photoim:lge.and thematic. Planimctric maps shownatuml :lnd manmade features. such asrivers. lakes. roads. milroads. towns. andland b o u n d a r i e ~ . but do not show relieffeatures. sueh as hills or valleys. The lattcr may be labeled. however. A road mapis a pl:wimetric map. Topographic mapsshow both features and land elevations.Pholoim:lge maps. such as onhophotoquads and orthopholOmaps. arc derivedfrom aerial phOlogmphs that havc becncorrected 10 eliminate distortions due toperspective or camcrJ till. T h c ~ e mapsare related 10 standard coordinate s y ~ t e m sbut show details that do not usually appear on convcntional maps. Thematicmaps. or maps portrJying a specialtheme. show information about:l specifictopic such as geology. minfall. populalion. Mlil (pedology), or vegetation.Thematic maps include geologic maps.which ~ h o w the position. structure. andcomposition of rock units and surficialmateri:lls and the nature of b o u n d a r i e ~between rock types. such as faults anddepositional contacts: geophysical maps.which show variations in geophysicalproperties. such as gmvity or magnetism(Figure 2): hydrologic maps. which showinformation about water resources: pedologic maps. which show distribution andcharacter of soils: liOd land-use maps.which indicate the areas that arc beingused for agricultural. recreational.

wilderness. urban. or other purposes.Because of their usefulness to theprofcssional geologist and bcc:luse theyarc often confused by the layperson. lOp-ogmphic and geologic maps arc describedin furthcr delail in following sections.

Topographic MOP5Every geologic process leaves a markon Earth's surf:lce. Wind and water erosion. glaciation. and volcanism leavetheir respective signatures as characteristic landforms. Unlike other maps.

a topographic map shows these threedimensional imprints. as well as m:lnmade features. Relief (mountains. hills.valleys. and plains). bodies of water(lakes. ponds. rivers. canals. andswamps), and cultuml features (roads.railroads, towns. and land boundaries)arc depictcd on topographic maps.On a comour map. relief is shownthrough the use of contour lines - imaginary lines on Earth's surfacc that connectpoints of equal elevation above or belowsea level (Figure 7a). A contour interval.

the clevation difference between t.....o adjacent contour l i n e ~ . is genemlly a eom.tantvalue chosen according to the groundslope and map scale: It !l1:ly v:lry. how.ever. on a singJc map to \how relief fea-tures more precisely. Contour intervabrange from 5 to 1.000 feet (Zumbergeand Rutford. 1983).Widely spaced contours Indicate flat

:lTeas or arC:lS with a gem Ie slope.whereas closely spaced c o n t o u r ~ indicatesteep terrain such as mountains or c 1 i f f ~ .Index contours. which arc usually everyfifth contour line and arc drawn withheavier lines than other contours. list elevations. Spot elevations may be given forcertain locations, such as mountain summits. road intersections. or lakes. Benchmarks indicale point!> at which the landelevalion has been preci!>Cly determinedby survcying techniques and arc markedon land by b m s ~ plates that arc pennanenlly filled on the ground. These can befound on Ihe tops of remote mountains aswell as on the ~ i d e w a l k ~ of major cities(Photo I). Each bench mark is shown on atopographic map by the leiters "8M,"followed by a cross and the measured elevation. When contour lines cross streamfilled valleys or canyons shown on a map.they bend upstreafll: the contour resembles lhe lellcr ..v .. with the apell pointingupstream (Zumberge and Rutford. 1983).On a shaded-relief map. thc land isshaded to simulate the effect that sunlightwould have on the term in. The paltern oflight and dark accentuales the shape of

physical features and c r e a t e ~ ,I threcd i m c n ~ i o n a l effecl. Slope maps create thi\~ a m e effect through the usc of differentc o l o r ~ and ~ h : l d e ~ 10 indic:lle ~ I o p esleepness.

Pholo I. Bran beoch mark sel in concrete. Th" i,o cootrol510'ioolhcl1 's port of nOlion-wide nelwork 01 permanent su.....ey mooumen15 used formoppiog and other purposes. The preci5e elevalioolrom a 5el datum plane. usually 5eO level, '5.hown os "H 15H and indicates Ihi. 510lion;s 15leel above .e o level. The preci5e locolion ollhi.slotion i. 0150 known and ;5 lied to the NotionalTriongulolion Network. The Meodes Roochtriangulation .Iolion is located ot 10liludeJ9IJ'26.686"N . loogitude 983230.506.........,obout12 mile5 north of tUC05, Koo5O' and i'lhebose point or origio olgeodelic po,ition5 and di.reclio05 in Ihe lrioogulotion net of the UoitedSlole,. The Meade. Ranch stolion i5 at the iunclion ollhe moin e051_wesltronscontinentol triongulOlioo orc, which slretche.lrom Ihe Allo"tic tothe Pocilic coo.15, ond Ihe moi" north'50uth are,which follows opproximolely Ihe 98th meridionIrom the Conadion border 10 Ihe Rio GrandeRiver ollhe Mexican border. Pholo by DonDupr05.

""CALIFORNIA GEOLOGY July 1990


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lA5lE 1.MAP SCAtES AND COlRESPONOING AlEAS ON THE GROUND.from U.S. G.oIogocol Sunoe): 1981b.

""'" Stondord Quadrangleon Mop Ouodrangl. Siz. NR".- R.presents IlQl. lOttgl {Squo!"e Milell1:24,000 2,ooof..1 1l'.r 7YI min"". 4910701:62,500 neony t mile lS .1 5 minule t9710 2821:250,000 neorly 4 miles 1' .2 '0.1 ' .3" 4,580 to 8,6691:1,000,000 nearly 16 miles " ' . 6 ' 73,73410102,759' 1 ' . 3 ' is the .Iond


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Gcologic maps can be used 10 locateminerJI dcposits becau!>C specific rocktypes or structures (such as faults) areoftcn associated with ~ p e d f i c d e ~ i t s .They can a lso be used to locale wurccs ofgroundwater or const ruct ion m:llerials(sand and gravel. or flagstone) to determille the suit:lbility of areas for agricullUre or urban development. o r t o idcntlfypotential geologic hlu.ards (such as land~ I i d e s or earthquakes). Geologic m a p ~provide an enormous amount of information needed for deciphering EiHlh's longand complex geologic h i . ~ t ( ) r y .

WHERE TO OBTAIN MAPSDivi$ion of Mine$ ond GeologyThe Divi.'>lon of Mines and Geology'sPublic Information Office provides diverse aspects of geologic and mining information 10 the public. Geological.geophysical. and seismic maps ofCaJifornia arc available for reference and/or forsalc. A good way to find out wha t Division maps and other publications areobtainablc for sale is to ~ q u e s t a free

"List of Available Publications" from:Division of Mines and Geology. P.O.Box 2980. Sacramento. CA 95812-2980(please include your return address). Division maps and publications can also beordered by mail from the above address.Division maps and other p u b 1 i c a t i o n ~may be examined in person and/or pur{'hased directly over the counter at Division l>Ublic Information Sales Offices atthc following locations: Public Information and Publications Officc, Division ofMines and Geology. 660 Bcrcut Drive.Sacr.ll11cnto. CA 95814-0131 (tel. 916445-5716); Division of Mines and Geol

ogy. 107 Soulh Broadway. Room 1065,Los Angeles, CA 90012-4402. (tel. 213620-35(0). and Division of Mines andGcology, 380 Civic Drive. Suite 100.Plcasant Hill. CA 94523-1921 (tel. 21362().3560).Out-of-print Division maps and otherpublications may be consulted at the Division Library facilities in the Sacramento.Pleasant Hill. and Los Angeles offices.Division Library eollcctions in SacrJ'mento and Pleasant Hill also contain

other map resources which the public mayconsull. Thest resources include histoncmines and mineral resource maps. topographic maps. orthophotoquads. USGSatlas fo lios . f lood control maps. and aVlI.ricly of other published maps and atlasesrelatcd to the eanh sciences. Further information about map collections may

be obtamed by (:alling the S:l(:r:llllentOlibrary facility (tcl.916-327-1850) or lhePleasant llilllibr.H) facili ty ( le l 415646-5941).u.s. Geologicol SurveyThe Map Dlstnbutlon Section (MDS)of the U.S. G e o l o ~ l c a l Survcy (USGS)sells by mall a ll geologic and topographicmaps publishcd by the USGS. MDS distributes. free of charge. indices titled

"Index and Order Form for TopographicMaps of Culiforniu" and "Index andOrder Form for Geologic Maps of Califorma." Readers may request these indicesby writing: MOS. USGS Map Salcs. Federal Centcr. BO\ 25286. Delwer. COtl0225 (tel. 303-236-7477). Be ~ l l r c toinclude )'our return addrcss.The USGS Book and Report SalesOffice for the westcrn United States sellsthe "List of USGS Geologic and WalerSupply Maps of California" for $4.75.This book includes all available USGSgeologic map publications specifically ofCalifornia. This book can be obtainedfrom: USGS Book and Report Sales. Box25425. Denver. CO 80225. Include return

a d d r e ~ ~ and make checks jXlyable to theU.S. Geological Survey.The USGS has an mformation network

of Earth Science Information C e n t e r ~ thatoffer convenient o\crthe(:ounter sales ofmaps and reports of California. Information questions arc also answered. Therearc three USGS Earth Science Information Centers in California at the followinglocations: Earth Science InformationCenter, U.S. Geological Survey. 7638Federal BUilding. 300 North LOll AngelesSlreet. Lrn. Angeles. CA 90012 (tel . 213894-2850); Earth 5cicn(:c InformationCenler. U.S. Geological Survey. Building3, Room 3128, Mail StOp 532,345 f.'liddlefield Road. Menlo Park. CA 94025.(tel. 415-329-4390); Eanh Scicnce Information Office. U.S. Geological Survey.504 Custom House. 555 Battery Street.San Francisco. CA 94111. (tcl. 415-5565627).Although the popular USGS 7.5mmOle and 15-nunute quadrangle maps ofCalifornia arc available at Earth ScleoceInformalion Cenlers. they arc also frequently sold at a var ie ty of map stores.

sponing goods stores. and surveying andmining equipment stores in rno!>! California cities. Locations lind telephone numbers of such s t o r e ~ can be loca ted in thetelephone book Yellow Pages under Iheheading "Maps-Dealers."

U.s. Bureau 01 land MonagementThe U.S. Bureau of Land f.lanagement(BLM) compilcs and distrioolC\ maps ofCalifornia that indicate land ov.ncnohlp

~ t : l t u s . Privlltc. Federal. and State lamh- such as parks. m o n u m e n t ~ . and lllllitary r e ' \ C f \ ~ J t l o n s - arc delineatcd. M a p ~arc of V'Jrious '\Cales and many a re ofI: loo.OCXl scale. The BLM also m:llntamsrecords of land holdings. For informationcontuct: BLM. California State Offi(:e.2800 Cottage Way, Room 2807. SacramenlO. CA 95825. (leI. 916-978-4754).There arc foor additional BlM dl\tnctoff ices where thc public cun go for theover-the-coumer ~ a l e s and IOforrn:llIon

aboulthosc particulur arcus. Theseoffices arc locatcd althc followlOguddresscl>:ijlM Bukersfield District. 800 Tru)l(unAvenue. Room 302. Bllkersfield. CA93301 (tel. 805-861-4191):BLM California Desert Diwict. 1695Spruce Street. Riverside. CA 92507, (tel.714-351-6383):BlM Susanville District. P.O. Box 1090.705 nail Street. Susanville. CA 96130(lcL 916-257-5381): andBlM Ukillh District. 555 L e ~ l i e Strcet.Ukiah. CA 95482. (tel. 707-462-3873).U.S. Forestry ServiceThc U.S. DcjXlrtrnenl of Agriculture

(USDA) Forestry Service prejXlfCS ands e l l ~ recrcalional maps of Federal forestrylantls in Californiu. For addltlonalmformation write or telephone: U.S. DepanlIIent of Agriculture Forestr) Service.Public InqUIries. 620 Sansome Slreet.San Fnmcisco. CA 941 I I (lcl . 4157052890).Depository Librarie$

M a p ~ of California. including manyrare hhtorical maps. can be examined utcertain Jibruries within the ~ t a l c designated as 'depository l i b r a n c ~ . " Suchlibrarics recelvc copies of .. II Fedcral andState lIIaps of California sold to the public. Deposllory hbr.tries in California 10 dude; The SCutc Library in SaCTlllllento(tel. 916-322-4570). all Uni\'Crsity of California campus hbmries, and municipall ibrJry systems in Los Angeles. SanDiego. San FranCISCO. und Oakland. AllCaliforniu Statc Unl\'Cf.'olt)' libmries andCalifornia Junior Collcge l i b r a r i e ~ contam extensive collections of maps. ManycOlllmuOlty l i b r J n e ~ . historical societies.and private institutions throughout Californlil also have notable map collections.

156 G\UFORNIA GEOLOGY


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Borlcer, Vicki, 1986, forhort's d i s a p ~ o r o n c elinked to mop, New Hayen Register, December 21. p. A4B.

Chamberlin, Wellmon, 19S0, The round eorth onflol paper; mop prolecr,ons used by co"ogrophers: Notionol Geographic Society, 126 p.

Compron,Il:.R., 1962, Monuol of field geology:New York.. JohnWiley & Sons. Inc., 378 p.

Fabiano. E.B., ond Peddie. N.W. 1980. Magneticdeclinorion in the United States -epoch1980: U.S. Geologicol Survey Miscelloneou.Inyestigotions Series Mop 1-1283. scole1:5.000.000.Hines, RA. 1986, Mop location literacy- howwell does Johnny Geologisr reodi; Discus.ion: Geological Society of America Bulletin,y. 97, nO. 10. p. 1283.

JennIngs, C.W.. 1977. Geologic mop of Coliforn,o: Colifornio Diyision of Mines and Geology Geolog'c doto mop no. 2, "ole1:750,000.Merrill, GJ(, 19860. Mop locotion lirerocyhow well does Johnny Geologist reodi:

REFERENCESGeological Soclery of America Bullerin,Y. 97, no. 4, p. 404-409.

Mer"lI, G.Irl, t986b, Mop locotion IIterocyhow well does Johnny GeologIst reod1; Re-ply: Geological Society of America Bullerin.y 97, nO. 10. p. 1284.

Merrill, G.K., 1987, Mop location lirerocy _ howwell doe. Johnny Geolog ..1 r e o d ~ ; Reply:Geolog'col Society 01 Ame,ico Bulletin, y. 98,no. 5. p. 619-620.

Nelson, R.E., 1987,Mop locotion I,rerocy _ howwell does Johnny Geolog'st reodi; Discus_sion: Geologicol Society of Americo Bulletin,Y. 9B, no. 5. p. 618.

Roisz, fysicol geology: Harper &Row, New Yorle, 612 p.

Thompson. M.M" 1979. Marx for Americo: U.S.Geologicol Survey, 26 5 p.

U.5. Department of Ihe Army, 1969, Mop reading: fM 2126.U.S. Deportmenr of rhe Atmy, 1983, Grid. andgrid references. TM 5_241_1,

U.S. GlIOlogicol Survey, 1978, Topogrophic mops:brod'ute, 27 p.U.S. Geological Survey, 1979, Topographic mops;silent guidel for ourdoorsmen: pamphlet.

U.S. GeologCldrongle, Socromento County, 7.Sminuteseries (topogrophicl, scale 1:24,000.

U.S. Geological Survey, 19810, How to orderlondsat imoges: pamphlet.

U.S. Geologicol Survey, 1981b, Mop scoles:pamphier.

U.S. Geologicol Survey. 1982, Geologic mops;portraits of the eorth: brochure. 19 p.

U.S. Geological Survey. 1983. Topographic mops;lools for planning; pamphler.Zumberge, J.H" ond Rutford, R , H ~ 1983, loboro

lory monuol for physical geology, s i ~ t h edition: Wm. C. Brown Co.. Dubuque, 187 p.

Greenwich Mean TimeTines of latitude have definile startingL and finiShing poinls because theyare nleasured in degrees starting from the0" latitude atlhe equator and increasingto 9O"N. at lhe Nonh Pole or 905. atlheSouth Polc. For lines of longitude. however. there are no naturJI slarting andfinishing points and the Slarting poim i:.therefore arbitrary. Longitude lines, ormeridians. arc imaginary nonh-southlines that pass through the North andSOUlh poles.Prior to the ISSOs many Europeancountries adopted their own zero meridians that were used to determine the dailytime standard for that panicular count ry.These local limes were more or lesl> adjusted to the position of the sun at noontime on a certain area. such as at a capitalcity. At that time the speed and efficiency

of transport by train and ship allowed anexpanding number of travelers to visit for-eign countries. However. travel timetablesbecame confuslIlg because of the differcnttime zones. Many tra\'elers missedtheir scheduled rides on railroads andships because they could not keep abreastof the correct times in different countries.

PhOl0 1. Geophysicist osrridethe prime meridion ..in front of the Royal Greenwich Ob.ervorory.fnglond. Photo byMargie Young


14/24

Photo 2.n.. gote clock oubid. the courtyard 01 rho Royal Gre.nwich Obs......otory. It IhoW1Grnwich M.on Time rhroughout rho ~ a r . Pltoro by te l YOllngl.

It became necessary to find a commoninternational zero meridian so that acommon time standard could be used(Malin and StOll. [984).In 1884 an international conference ofastronomers met in Washington. D.C.

and decided that the line passing throughthe RO)"oIl Greenwich Observatory ncarLondon .....ould be adopted as the worldstandard prime meridian, All other linesof longitude are numbered east or west ofthe Greenwich meridian and increase to180" EaSI or 180" West. For example. thelongitude of Sacramento is 121"29'2rWcst of the Greenwich meridian. Following acceptance of the prime meridian.most countries adopted a universal time7.one s y ~ t e m based on the Greenwichmendian, called Greenwich Mean Time(GMT). Univers.ll Time (UT). or ZuluTime (ZT), Twenty-four time zones wereadopted with 7.one ooundarics determinedby local governments,Royol Greenwich ObservatoryMany d i s a ~ t e r s at sea in the 17th and18th centuries were directly caused by ignorance of position. One nOlable disasteroccurred when an English fleet waswrecked on the rocks of the Scilly Islandswith the loss of over 2.000 lives. AdmiralShovel!. who was in charge of the f1eel.believed he was safely headmg into IheEnglish Channel.Determining latitude at sea could beochieved by celestial observalions. Reckoning longitude at sea when landmarks

.....ere not available. ho\I.ever. was muchmore difficult. To solve Ihe problem, in1674 King Charles II assigned the English aSlronomcr. John Flamsleed, to buildthe Royal Greenwich Observatory. It wasfinished in 1676 and is the oldest existingaSlronomical observatory. Astronomersbelieved that. like latilude. longitudecould be determined by astronomicalobservation (Malin and StOlt. (984).By carefully observing the Moon and

the Slars with telescopes. a ralher complicated method of locating ships at sea wasdeveloped. called the "lunar distantmethod." The lunar distant methodproved to be difficult 10 usc and prone toerror. For example, a measurement errorof only one minute of arc in the positionof the Moon would resull in an error inlongitude on Ihe surface of the Earth ofaooul 30 miles (Malin and StOll. 1984).

TimeA more effeclive solution to the problem of finding one's longitude at sea wasthe invention of an accurate chronometer.

or clock. [n 1728 an English carpenternllmed John Harrison presenlcd the firstaccurate marine chronometer that couldkeep prccise time for months on end, Inrelation to the sun, the Earth rotates onedegree of longitude every four minutes. Ifa timepiece were set to the time at a localion where the longitude was known-such as the Greenwich meridian - thenas the ship proceeded on its voyage. thedifference between "Greenwich time"and the time on board Ihe ship (usuallytaken when the sun was direclly overhead- or local noontime) would provide thelongitude of the ship and ils distance inmiles east or ~ ' C s t of the Greenwichmeridian (Lewis. 1982). By the mid1700s marine chronomelers were usedworldwide as an effective means offinding longitude at sea.Scienlists at the Royal GreenwichObservatory kepi the precise time withclocks and periodically adjusted Greenwich Mean Time from astronomical 00

servations. Greenwich Mean Time wasdistributed by means of a large bright red"time ball" located at the Observatorythat could be easily seen from the surrounding area. The ball was cranked byhand up a tall pole on top of tnc: roof ofAamsteed's house al the Observalory andreleased by an astronomer in the base-ment precisely at I p.m. each day. Thetime ball lit Greenwich was the world'sfirst public lime signal and was easilyseen from ships on the Thames and in thenearby Port of London. AI the momentthe time ball dropped, mariners set theirchronometers and took Greenwich MeanTime to sea so they could accuratcly findtheir longitude. Similar time balls wereused throughout the world before observalories scnt oottime signals by telegraphor radio (Malin and StOll. 1984).DQII Dllpms. DMG.

REFERENCESl .w' 8renda Rolph. 1982, Th orch lor long,_

rude: Oc.onl, JonU'Ory, p. 18-23.Molin, Sruort, and Sroh, Coral., 1984, TheGre.nwich meridian: W 5 Cowell Ltcl . SO p.

15. CAUFORNIA GEOLOGY


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Mine hoist, Empi.e minll. The m,ne" we'e lowered into III. mine to begin thll wo.k of Ihe .hi/t.DMG Photo File.

Mine Safety1893M an has mined minerals from theEarth for over 6.000 years and underground mining has historically beenarduous and dangerous. Occasional caveins. pop-outs. c:..plosions. and ocheraccidents have killed or injured minersIhroughoullhc world. However. becauseof improved equipment and increasedsafety practices. incidents of mining :Iedd C n l ~ in the United States have greatlydecreased since the early 1970s. Thefollowing excerpt from California SI:lIcMining Bllrcau Bulletin No. 18. Till'Motlier Lode Region ofCtlfi/urllio (1900)by W. H. Storms. p. 40-42. describessafety procedures u ~ e d in Mother Lodegold mines of California at the turn of thecemury. Mining operations in Californi:ltoday must adhere 10 numerous FedcrJland Slale safety rcgulations. and thcseoperations are inspcclcd rcgularly.

MINE BELL SIGNALSII having come to my IIolice tllol in some locali

ties the legalized code of mine bell signals is notin use, it oppeors imporlonl to call Ollention 10the fact thaI the California Slate legislOlureadopted a code of mine bell ,ignols May 1, 1693,which should be odopled by all mines regardIe.,of custom or diffe.enl practice elsewhe.e. The.eis a liability ouoclled fa . Ihe liOn-use of Ihe legal,ignol code. fa . the benefit of Colifo.n;o mine"the legal "gnol code is he.e published.

California Code ofMine BellSignals

1bell, to hoist. See Rule 2.ISee Iisl of rulesbelow.]I bell, to Slap, if in motion.2 bells, to lower. See Rule 2.3 bells, man to be hoisted; run slow. See Rule 2.4 bells, start pump if not running, or stop pump ifrunning.

1-3 bell" start A. slop oircompressor.5 bells, send down tools. See Rule 4.6 bens, send down limbers. See Rule 4.7 bells, occident; move bucket Or cage by verbalorde" only.1-4 bell., foreman wonled.2-1-1 bells, done hoisling until called.2-1-2 bells, done hoisling for the day.

2-2-2 bells, change buckets from o'e 10 wale.,a. vice vena.3 - 2 ~ 1 bells. ready 10 shoot in lhe shaft. SeeRule 3.Engineer' ignol that he i. ready to hoist is to

raise the bucket or cage two feet and lower ilagain. See Rule 3.levelholl be de.ignoled and in.erted innotice hereinafter mentioned. Se. Rule 5.

RulesFa. thll pu'po.e 0/ enforcing and property

underslonding the above code a/signals, thefollowing rules o.e he.eby established:

RUlE 1. In giving signals make st.okes on bell atregular inlervols. Thll ba . (- I must toke the .ometime as for one stroke of lhe bell, and no more.If timber, lools, the fo.emon, buckel, or cage ar ewonted to Slap a t any level in Ihe mine, .ignol. bynull'be . of slrokesOn the bell, the number 0/ thelevel fi"t before giving the .ignol fa . limber, tool.,etc. Time betwllen .ignols 10 be double ban( - -I . Example"6- - - 5 would mean to slop at sixth level withtool.4__1_1_1__1would mean stop at fourthlevel, man on, hoi.t.2 - -1-4 would mean slopol.econd levelwith foreman.RUlE 2. No person muSI get off Or On Ihe

buckel Or cage while the some is in motion.Whenmen are 10 be hoisted, give Ihe signal fa . men,Men mu.1 then get on the bucket Or cage, thengive Ihll signal 10 hoist. Bell cord must be in reach01 the men on the buckel or cage 01 slotion.Ruu 3. Alte. signal "Ready to shoot in shalt,"

engineer must give the signal when he is .eodf tohoist Mine" must then give the signal of "Men tobe hoisted," then "spil/u,e," gel inlO the bucket,and give the signal to hoist.

RUlE 4. All timber, tools, etc., "lange. than lhedepth of the bucket," 10 be hoisted or lowe,"d,must be secu.ely lashed at the upper end to thecoble. Miners must know they will . ide up ordown the shaft without catching on 'o


16/24

Earthquake Safety AwardThe California Earthquake SafelyFoundation presented the "Alfred E.Alquist A .....ard for Achievement in Earthquake Safety" 10 Stanley Scott of Larayclle :mu ChrislOphcr Arnold of Palo Alloduring California Earthquake Prcp:Hcdn c ~ s Moruh (April 1990). The p r c . ~ c n I 3 l i o n ~ were made by Found,ltioll ChairmanWilfcru Peak 31 the annual a w a r d ~ luncheon held in April. in S'lcramcnlo. Theaward. :m engraved silver mcd:llJion. ISgiven [0 recognize indll'iduals who havemade O U I ~ I ; t n d i n g com r i b u l i o n ~ 10 sci\lllicsafely in CaliforlU3. II is n,lIlled for Sl.lteSenator Alfred E. Alquist. a long-limesupporter of s c i ~ m i c ~ a r c l Y progr.l1m. IIICalifornia.Stonley SeoltStanley SCOlt, adminlslralOr and fC-

~ a r ( h c r 31 the University of California atBerkeley .'>ince 1941. b A.'>sislam Direclorof the [n.'>tilute of Governmenlal Studies.a position h e has held since 1958. Hisinlerest in earlhquake hazard mitigationbegan in the early I950s and continuesloday. He ha.'> .'>Cn'Cd in variou.'> consulting and othcr capacities for the Pre.'>identsOffice of Science and Technology: theWe.'>lern Governmenlal Re.'>carch A.'>.'>ocia-tion: lhe California Joinl Commillee onSel'mic Safely: the Nalional ScienceFoundation: Th e California Coastal ZoneConscrvallon Commission: and the BayArea Regionul Earthquake Prcparednes.'>ProJect. li e hus been a vulued member ofthe California Seismic Safety Commi.'>.'>ion .'>ince its inception in 1915. and ha.'>

.'>Crved tenm both as Chil l rman andVlce-Chamnan of thai organll.ation.Scott n:ceivcd ,I number of Olher pre,tl

glou.'> CIVic and profcssional aw,lrd, forhi.'> ~ o n t r l b u t i o n . ' > 10 the under,tandingand mllig,Itl0n of earthquake hai':ard.'>.The.'>C indude a commendation f rom theCalifornia orncc uf Emergency Services.and a resolu tion from the California Leg'blalure for his effon, on behalf of theJOll1l Committee on Sel.'>mie Safel)'(predece.'>.'>or 10 Ihe Seismic Safely Commi"ion). li e ha., wril1en o r has beencoauthor of n13ny [Japer, dealing "ithearthquu"e halard, :lrld mitigation.publi,hed locally and nationally.ChristopherArnold

Chris lopher Arnold has been involvedin research on archileclurul a,pecls ofe;lrthquakc, .'>lnce 1916. li e i, lhe fiNarchilectto be hunored by the Foundationwith the Alquis t Medal. Following lheOctober 11. 1990 Lolna Prieta earthquakehe was .'>clel'ted by GOvernor Dcukmejiana.'> a lIlember of the select panel of e x p e r t ~"tuJying the e o l t a p ~ e , of lhe Inter.'>tate880 viaduct and lhe Oakland Bay Bridge.

Arnold i a grudualc of London Unlvcr"ny: he received an M,A, degree in Architecture fronl Standford Unlver.'>lly. Hei the cO:lUthor of a lext entitled "Huitding Configur.Jtion and Se"mk Dc.'>lgn.whIch has been lrun"lated imo ,ever:lllanguage.'> induJing Ru",ian. He i theauthor of a number of other arl1e1e, and

papers on the architecture of sei.'>Elllc de, ign. Arnold has pre,ellled lIlany profe,,ion'll work"hop.'> and seminar.'> on .'>ei.'>rI1icde.'>ign and e:mhquake h'llard, mitig,ll ion. and has .'>[Xl"en on the subjecl beforenumerous lechnical group,. He i.'> a member of t he Ad Hoc C01l1nullee on lheInternational l),:eaJe of Naturul I-IalardReduction. "pon,on:d by the NationalRe concernedaboUI future earthquake .'>afety in Califor-nia may eomribute direcl ly to the Foundation. P .O. Box 22912. Sacrame11lo.California. 95S22. ,. lVilfml W. P/'{/k,Colijol"l/i(l E(lr/!lqlwkl:' Sa/l:'ly FOlil/dation.

Trivia(1) Thl.' I,!cographlc cemer of an area mOl> be 'kfin.:d u, lhe center of

~ r a \ i l y of Ihe ~ u r f a c c . or lhal pOln1 on "'hlch lhe ,url'ace oflhearl'U would balance if il "ere a plane ofunlforrn Ihlckne" Where1) lhe geographiC eenler of CalJforllla'!

(2 ) flow old IS lhe olde)1 known ~ e o l o g l c map"(3) The lenglh of lhc day" dClcrnlln.:d by Ihe rOlalLon of Ihe bnhl>y u)lng a.'>trontlmieal ob\erVal'on Ho".:vcr. becau,e the l:anhha) a nonuniform rale "f rOlal,on and a unlformt,mc: ,cate I' re-qUITed for many llOllng appllcatlon,. ho" do )


17/24

A Page for Teachers

RockCrossword PuzzleRock h defined as an aggregate of one or more minerals or a body of undirrercnIlaled mineral matter. Rocks are broadl)' classified into three groups: (I ) igneousrocks. (2) sedimentary rocks. and (3) metamorphic rocks. For basic informaTion onrocks sec Division of M i n c ~ and Geology Special Publication 33. "Minerals andRocks" ($1.00), available from DMG. P.O. Box 2980. Sacramento, CA 95812-2980.

The crossword puzzle can be used as a special inlerest activity after a b a ~ i c lesson onrocks. It is suitable for grades 61hrough [2. Pllz;11' CO/lr/ l ' , fy O/ClUO/ S/(/(/IIIII, Dept"1-IIlt'lll ojGeofogiml Sdellct's, C/Jliforn;() Sill//.' Ullirersily. Fllllerloll,

ACROSS ClUES1. sedimentary 'o,h o t c ~ m ...lote in4. plo!I!Y metamorphic rock full 01 mico9. an ignea... ratk wilh ha le5 and f1owline511. edimentary rock compo.ed 01 roundedpebble.12. parent ratk of marble14. edimentary rack that lorms aro ...nd springs15. light colored cry.talline ign ..o ... ro dCammon in the Sierra Nevada16. dark calar..d c r y ~ t a l l i z e d ignea.... ro d22. a foamy volcanic ratk that floc!> in water23. a hard black arganic ...dimentary ratk24. a metamarphic ratk with bands of calor2S. ~ e d i m e n t a r y ratk campased al angulargrav..1

DQWNClUES2. sedimentary ro


18/24

You are invited to attend the national1990 ANNUAL MEETINGof theASSOCIATION OF ENGINEERING GEOLOGISTS

"Engineering Geology For The 90's"Pittsburgh, PennsylvaniaOctober 15, 1990TECHNICAL PROGRAM

PtTTSBURGH;;'" ....... Mine Subsidence Hazardous Waste Investigations & Remediation Rock Slopes River & Lakeshore Stability & Erosions Problems of Appalachian Geology Applying Computers to Landslide Problems Dam Foundations & Rehabilitation Facility & Environmental Siting SlUdies HydrogeologylHazardous Waste

SHORT COURSES Application of Microcomputers to RockSlope SlabililYAnalysis An Introductionto Geosynthctics: Selection Dcsigo. &Applicatioo to Wastc Facilities Geological Aspects & Issues of Nuclear WasteDisposal Environmeotal Applications ofEngineering Geophysics

SYMPOSIA Mine Subsidence- Prediction aodControl (32 P:lpers. Oct. 2 & 3)

(From page 161)

Answers to RockCrossword Puzzle

Professiooal Registr3tioo for Geologists;History. Need. Currcot StatusFIELD TRIPS

Ciocionati to Pillsburgh (pre-meetingtrip) Hazardous Waste Landfills Dams & Highway Constructioo LocalPittsburgh Geology Tours

EXHIBIT PROGRAM Featuring over 55 Compaoies withreserved Exhibit Booths Exhibit areais io the Centrally located Ballroom ofthe Hilton Hotel (Space still available!)

To request a brochure and forfurther information on exhibits andregistrations contact: AEG. MEMS P.O. Box 270 Greensburg. PA 15601 (412) 836-6813' 800-343-5129' 800441-1674 (in PA)' Fax (412) 836-6817

I'LIA YIE R '5 "P l"c H I '51IJH fi A LP A '5 A R 1'1. AV AIt ONG LOM ERA T E B T 5

R E 0 0 E HP P l1 I M E S T O NEH M AE E T U FIAIORA N I T E

Y M TA t; AB BR t> 'QT R A B 1>I Y 5 5 U IF T A I A AI>UM I e E COlA L 0 RZ T I T 0Z A ZG NE I 5 5T

'DR E e e l l A

162 CALIfORNIA GEOLOGY


19/24

Books r....iewed in thiS seclion o, e nol ovoiloble lor pv,chose F,om DMG.

, , ." ....-.---......-.-.--.. .K ... ' .........._---...__ .....

oCJCJI:::J..

G.ologic mop 01 the l o ~ e Mead area, nor1h.w.,I.rn Arizona. loulhern Nevada, and south.eastern Colilomio. The la, Vegol Volley Iheorzone (LVSZI and the L o ~ e Mead sheor zane(LMSZl connect areas of extensionolloulling i...monner ,imilor to !hot 01 transform Ioul!s thcr1conned ac.c",ic ,preoding cenlers. AI! of theextensio... i... the northern Colorodo River t,oughwos transformed northwestward by Ihe LVSZ ornor1heostword by the LMSZ. Reconslruction ofs t r i ~ e - s l i p fouln allow, reconstruction top'eedensional configuration. Data allowed lor 34miles of righl-Iole,ol slip on the LVSZ to be reco ... llrucled. restoring the soulhealtern McCulloughRange 10 locality {II (arrow ,epr.lenls rKonItnKlion vedorl. This reconllruction r.oligns the\'Vtie..ler Pass thOVlt (WPT) with !fl. Go. . Peokthovst,GPl1 and !fI.. K"Y'lone thov'I (KT) With !fl.Muddy Mounloins thovst!MMT). Reltorohon of12 mil..s 01 movement on one branch of th.lMSZjudoposes each half 01 the Hombl,n Boy-Cleopat,o volcano (HCV) and movel the southeasternMcCullovgh Range to !fie l'lOI1Ileast po ....on (21Restoration of 40 mil.l of lotol dllploc.",.nl ofthe LMSZ realign, a dISI .....c h . deposihongl contact berwee ... T.r1lory and pre-TerTtory rocks atFr.nchmon Mo!.onto,n (Iacobon Al wi!fl a very.imilor conlocl in !fie .outhern Viri,n Mounlolns!location BI. and 'estor.1 rh . south.olrernMtCuliough Rang. toposition adjacent to!fl. Colo'odo Plateau (3J. GBF Gold Butr.Io ......

........ ....... .... ._.....SYMBOLS_ . ,--_. __ , t"',....l...._. _ . I , .. . ,

n. ......."" ~ . _ .. ,...,

- '--_ _ _ ' ' - _ c ~ " - _ _ _ ' ~ ' - _ C ~ " _ _ ~ ~

Oblique oenol view of a Pleislace...e age lava flow. show....... dark" From a ci...der co"'e i... upper m,ddleof photo. The lacolio... 01 Ihis o,eo is a lew miles north 01 Flogsloff. Arizona. PIlaIo by Peter l('elO....

GEOLOGIC EVOLUTION OF ARIZONA.AnzonaGeological Society Digest 17. Edited byJ.P. Penny and 5.1. Reynolds. 1989.Arizona Gcological Society, P.O. B o 40952, Tucson, AZ, 85717. 866 p. 560.00.hard cover. prepaid (includes postage andhandhng).Seven years In the making, lhe 35 papersIn thiS volume summarize the S l r ~ t i g r a p h i c .structural. and tcctonic (ValUlion of Arizonafrom Precambrian through Quaternary lime.Intended as a compendium of current knowledge of Arizona geology. the papen; synlhesiu previous .....00 ; with new data. ideas. lindconcepts as well as identifying unresolvedproblems fOf" fUlUrc research. Emphasis ISplaced on the geologic evolution of the stateas a whole ralher than specific local areas.The papers arc organized in ttrms of geologic eras: Proter01:Oic. P:alco'toic. MesozOic.and Cenozoic. The concluding secllon offerstopical studies in the areas of gcuphYSlcs.indusuial minerals. uranium. oil and gas.geothermal resources. hydrogeology. and environmental geology. California ~ a d e r s WIllfind much of interest In thiS research volumebecause many of the tectonic processes thatformed Arizona also affected the development of this state.

BookReviews

CALlfORNI.... GEOLOGY Jul,I990 163


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.. Oblique aerial View of spIres, bulles, and mesas01 Monument Volley, nortll 01 rile rown 01 Koyenro, nOrllleostern Arizona View,s to 'lie northSpire, ,n tile middle of photo are called "ToremPoles H The uppermost rock cop' on the bultesnorth 01 the TOlem Poles Ore mode of rile Toos"cShInarumpMember 01 the Chinle Formol,on andare underlaIn by the TnalSlc MoenkopI Forrnohan. Pholo by Pefer KreJon,

DraWIng 01 on old wooden stomp mIll used tocru,h ore, Cl(CO early 1900s,

In hi ' c"ay, "Tcl'lOm,' S c t l 1 n ~ uf ArllumtThrough G'lnce The,ene",ly reC"J!nlfcd ,JelJChmenl fauh 'lructure''pre' lOu,ly thought I" b,' thru,t faul"l arcpfilduce,J b) cru'taI e(len"'ln or 'tretchlng.In ",hlch lhe overlYing hive" Ix:ha"c' Indcpcndcnll) orthe underl)'ing hlox" "lcpoo!>lh II I Arilona:' fnre'a"lrle, e\plore, Ila'lll and R:lngc llllneralIfatmn a ~ , o { ' i a t e d "nh Illagmml,m ,mdn l J ~ l a l c ~ p a n ' l t l n , Repre-.enlatlw mineraid"trtCh fur .,hffcrcnll)'pc, of dept"'" arcuutllncl! An()thcr papcr f""u,e, un millemidepo'I" ea",ed b) Ihe Laranmlc O r o ~ e n ) .nlHahl) pllrph)'fY c"pper. a"'>c'ated "llh I ~ ncou' aCtl\ Ity 111 "ri/ona am) the "Iuth"e'tThe chronological -.eel ,on d", ," "l1h paper,Ile,,",nb,ng laIc Cem>l"ll' 1,'{'tunlC,' and ther,',ultlng pmtern' ofdcformatlun, 'edllllentallon and \'olc:lnl'm un Ila'io an,J Rangeland,capt' dc\doplllcnt. you Ill!, rC""'flll/anl"voil'anu", and lheir rod." In An/una and ad;acent b"rdcrland" anll a dl,cu"lon "f thehl"lUf) l\ f the C"I"rad" Rl\er andn ' GrandCan)'un I're'Cnllng C\ ,denee thai Ihe GrandCan)un "'a, cut 1O.t milium ) ' e a r ~ or Ie "The ""Iume c"ndud'" "nh" narrallve dc,croblng the 191111 Gc,,!ogic 1\lal' of An/una" hKh i , incl",Jc,J ", p:ln nflhc dlge,1Re""'",,,,II,,' S,It'", Hr',,,I,,,./.,,,,,1> 0

'" CAliFORNIA GfOLOGY July 19?O


21/24

SIO.OOS20.OOS 100

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S1".00S 6.00S ".00

S 8.00"00S 6.50S FRH 1.50

...........postoge ond toIft Ill;".

more. . .

ROAOSlDEGEOLOGYOflfTAH B)Halka ChronIC" 1990 Mount.tn Press Pub-lishing Company. 2016 Sirand "'"tnllC. P 0 ,BoA 2]99. Missoula. MT 59806. ]]5 P512.95. paptrbal.'k

THE '\ORTHERN ItlGHLA:-'OS OFSCOTLANO Fourth td.ll0n. B) G 5l o h n ' t l l 1 l ~ and W M)l.uf1I 1989 Bnll,h(ic,olog'l.'al S ... r ~ Anllablc from HMSOPubhcallons Cenllc. P 0 Bo\ 276. London.England SW8 .50TThe area deall "It II in thl' booll.'ompn)tsthe mainland of Scotland north of I h G ~ a lG I ~ n . lnl.'ludlng I h I l ~ b n d c : a n I s l D n d ~ TIllfourlh edlllon of l "oIUmf rcf1tl.'ls lhelnernl.e In rescoarch InIO .11 .sptcb of Ih tI ~ o k l t y of Ihe Northern HI,hl.nd) Bnefrtftrtnet Iii mado: 10 thc ,colO!) of Ih t s e . ~around norillern ScOlI:and

UGlONAl GlOlOGlC MAP SfRlfS (I 250.000 Kale)__ RGM I s.ocr-Ilto qIIOdrongt. 1982 . .__ RGM 2A Santo RotO qIIOdrgnWe. 1981 .__ RGM 3A Son hrnordi no quodrgngle. 1987 .............................__ RGM"A Weed qIIOdrgngl . 1987 .CALIFORNIA GfOlOGY__ I yeclr 112 ;11"1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .__ 2 y.oI'112" iuue.l .__ lock III,," [Specify volume ond month)lndividuol ill 1 Sl 00 eoch . . . . . . .

GIDlOGK.Al OATA MAPS 11:750.000 _ 1 . )__ GDM 2GeoIogoc mop of CoIifotll'lllll 1977. Folded .__ GOM 3GrOd)' mop of Coliforll'lllll and III eonti.. .ntol giM. 1980. Folded ,Rolled ImoMd II'IlVbel , . . . . . . .. . .__ GOM" G.otf>elll'd resour


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PAYMENTMUST 8E INCLUDED WITH ORDER

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flat-lying rock: (2 ) Caves and reefs: (3) land-scapes shaped by continental or alpine glaciation (includes Yosemite National Park);(4) Volcanic features and volcanic a"ivity(includes Lassen Volcanic National Park). and(5) landscapes and structures in areas ofc o m p l e ~ mountains (includes Sequoia andKings Canyon Nalional parks: Channells-lands National Park. and Redwood NationalPark).Each section includes a discussion of significant geologic fealUreS and processes. asummary of the geologie history. information about the park's history and geographicselling. a local ion map. illustrations. and asimplified geologic column. References areincluded at the end of each chapler.

Pacif,c Plol"THE EASTERN PACIFIC OCEAN ANDHAWAII, Geology of North America. Vol-ume N. Ediled by E.l. Win!erer. DonaldM.Hussong. and Robert W. Decker. 1998. TheGeological Society of America. P.O. Box9140. Boulder. CO 80301. 577 p. 12 plates inslipcase. $54.50. hard cover.

D ~ c o d f ! ofNorth Amuica G ~ o l o g ) ' is a research and publishing project sponsored byt h Geological Society of America in honorof its 1988 cemenary. This two-part set isvolume N of lhat series. Twenty-eight chapters present state of knowledge about the geology and geophysics of the northeastern partof the Pacific Ocean and adjacent parts of theNorth American continental margin. Theareal c o \ ' ~ r a g e is from the margin west tothe Hawaiian Seamount chain and south tothe equator. Major topics include regionalbathymetry and tectonics: spreading ridgesystems: Hawaii-Emperor and other seamountchains; sediments of lhe nonheast Pacific:and Pacific continental margins of NorthAmerica.Eight wall maps at a scale of 1:5.000.000su.mmarile the geology. tectonics. magneticand gravity anomaly pallerns. regional Stressfields. thermal aspects. seismicity. and neotectonics of North America and its surroundings are included in the volume. Together.the synthesis volumes and maps are the firstcoordinated effort to integrate all availableknowledge about the geology and geophysicsof a crustal plate on a regional scale.

GEOLOGY OF NATIONAL PARKS.Fourth edition. By Ann G. Harris; EstherTuule. Science Editor. and Sherwood D.Thule. Contributing Editor. 1990. KendallHum Publishing Company. 2460 KerperBoulevard. P.O. Box 539. Dubuque. lA52004-0539. M2 p. S34.95. soft cover.In this book 49 national parks (six are inCalifornia) are grouped into five divisions.based on categories of geologic concepts.Each section of the book is introduced by abrief overview of geologic features and processes dominam in the parks which make upthat group. Discussions of geologic componentS are given in the appropriate chapters.Throughout the text geologic topics of specialinterest are featured. The book progressesfrom simpler geologic themes to more complex ones - from discussions of landscapesand features developed by the Earth's external processes to the study of regions thatdisplay the results of the Eanh's internalprocesses.The five divisions of the book are: (1 ) Scenery developed by weathering and erosion on

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Rocks along major highways and selectedless-frequemed but geologically interestingroutes are described in this guidebook. Aflera brief imr..x:luction. the regional geologicprocesses in the three major geologic provinces of the state are discussed. Each chapterbegins with a general introduction and thencontinues with a series ofroad guides.Throughout the book the author describes therocks. and explains the historical geologicevents they record.The cIlapter on Colorado Plateau countryguides the reader through the well-exposed.flat-lying sedimemary rocks of southern andeaStern Utah. The chapter about the highcountry of Utah explains the geology of thesouthern high plateaus, central volcanicranges, and pan of the faulted. foldedSouthern Rocky Mountains in the nonh.The western desert of Utah is a land ofsalt. sun. and mountain ranges where streamsnever reach the sea. This area of the GreatBasin geomorphic province is examined inChapter 3. The book concludes with a discussion of the scenic and geologically interesting national parks and monuments of Utah.Photographs. maps. and figures are interspersed throughout the book,

,.,." .

GEOPHYSICAL FRAMEWORK OFTHECONTINENTAL UNITED STATES. Geological SOCiely of America Memoir 172.Edited by l . C. Pakiser am! Waller D.Mooney. 1989. The Geological Society ofAmerica. P.O. Box 9140. Boulder. CO8030 I. 826 p.A revicw and evaluation of Ihe presentknowledge of the structure of the crust and

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166 CAliFORNI,\ GEOLOGY


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the upper mantle of the continenlal UnitedStates, exclusive of Alaska, as determined bygeophysical ob$Crvations are pre$Cnled in thiscomprehensive work. II highlights some ofthe historical developments Ihalled to thisknowledge,Velocity models deri"ed from seismicobservations can be related to the structure,composition. and rheologic properties of thecrust and mantle and 10 imponant solid-tosolid phase transformation. Magnetic investigations, radioactive age dating, seismicity.and geological studies have revealed the

.....orldwide patterns of sea-floor spreading.continental drift. and plate tectonics. Imporlanl regional similarities and differencesha,'e been discovered. and simple conceptS ofisostasy and crustal deformal1on have beenmodified or discarded.The book contains four parts. The lopicsprogress from re'lew of the geophysicalmethods of studYing the Eanh's cruSt andupper mantle (pari I) to a region.by-regionre'le" of crustal and upper mantle structureCPUI 2). and from conlinental O\Ierviews ofstudies based on the differenl geophysicalmethods (part 3) to geological and petrological syntheses based largely on geophysicalresultS (part 4) . The volume concludes wllha discussion of major unsoh'ed problems Inlhis areaThe book is designed for geophysiciSlS.geologists. and graduate students,

EMIGRANTWILDERNESS ANDNORTHWESTERN YOSEMITE. By BenSchlfrin. 1990. Wilderness Press. 2440Bancroft Way, Berkeley, CA 94704. 186 p.$14.95, paperback.This comprehensive guidebook describesthe natural environment seen along the hiking trails in the Emigranl Wilderness andnorthwestern Yosemite area. The EmigranlWilderness is an 118,000 acre federallydesignated wilderness area in the StanislausNational Forest on Ihe northern border ofYosemile. It is an area of scenic viSlas, troutfilled lakes, r ~ walls, and quiet sceniccampsites - a hiker's paradi!lt. This middlemountain forest area is still uncrowded. andmany trails are open from lhe first of Mayuntil (Xtobcr.Distances. trailhead directions. and asummary of the natural features and scenichighlights are lisled for each lrip described inthe book. A numberof crosscountry routesarc given. There are also separate chaptersfor mOUnlain bikers. horseback riders, rockclimbers, and crosscountry skiers.Additional features Include chaplers on thegeology. rlora and fauna of the area. the human history of the area. and ehoosmg atra,1St"eral topographic maps. includmg onefoldoot map fscak, I Inch equals 2 miles).arc included with the book. Numeroos blackand-white photos Illustrate the gUidebook

UNITED STATES TSUNAMIS (IncludingUnited States Possessions), 1690-1988. 1989.By lames F. Lander and Patricia A. Lockridge. National Ckophysical Data Center,325 Broadway, Boulder. CO 80303-3328.265 p. Prepaid. $30.00. hard C


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STATE OF CALIFORNIATHE RESOURCES AGENCYDEPARHAENT OF CONSERVAnONCALIFORNIA GEOLOGY

DIVISION OFMINES AND GEOLOGYP.O. BOX 2980

SACRAMENTO, CALIFORNIA 95812-013\USPS 350 840

ADDRESS CORRECTION REQUESTED

DMG OFR 89-16SUMMARY REPORT: FAULTEVALUATION PROGRAM. 1987-1988.

SOUTHWESTERN BASIN ANDRANGE REGION AND SUPPLEMENTAL AREAS. By Earl Hart. Wil liam A.Bryant. Christopher J. Wills. Jerome A.Treiman. and James E. Kahle. 15 p . 2tables. I plale (scale 1:500.000). $6.00.A summary of faulls evaluated in thesouthwestern Basin and Range region(Inya County vicinity) for possible wningunder Ihe Alquist-PriOlo Special StudiesZones (APSSZ) Act is presented in thisreport. Faults evaluated in supplementalareas of southern California also aresummarized.

The APSSZ Act requires the StateGeologist to identify active faults and toissue maps of special studies zones inorder 10 regulate development "projects"near active faults. The purpose of the Act

SPECIAL REPORT 156MINERAL LAND CLASSIFICATION:PORTLAND CEMENT CONCRETEGRADE AGGREGATE IN THESACRAMENTO-FAIRFIELD PRODUCTION-CONSUMPTION REGION. ByDon L. Dupras. 1988. 14 figures. 10lables. 40 plates. $18.00.

In any urban land development. land-usedecisions concerning high-grade construction aggregate used in porlland cement concrete can best be made when athorough investigation of this resouree iscompleted. This type of aggregate is anindispensable building material and iscostly to transport.

is to reduce the hazard of surface faultingto structures for human occupancy. Citiesand counties affected by the regulatoryzones must regulate specified "projects"within the wnes in order 10 locate structures for human occupancy away from thetraces of aClive faults.

The southwestern Basin and Range region is the ninth of ten regions evaluatedunder a statewide plan initiated in 1976.Sixteen faults were sludied in this region.including the Ollo'ens Valley. Death Valley. Panamint Valley. and other importanl faults. Fifteen faults studied insupplementary areas include the Imperialand Superstition Hills faults (IrnperialCounty). Rose Canyon and related faults(San Diego County). Los Osos fault (SanLuis Obispo County). and Peralta Hillsfault (Orange County). Data on the recency of faulting and recommended zoning actions arc summarized for each fault

Land in the SacramentoFairfieldProduction-Consulllption (p.C) region wasclassified to indicate where significantsand. gravel. or stone deposits suitable forportland cement concrete (PeC) gradeaggregate occur or may occur.The Sacramento-Fairfield P-C region.as defined in this report. covers 855square miles and incorporales the greaterSacramento metropolitan area, inclUdingRoseville. Placerville. Elk Grove. and

West Sacramento. In addition. the regionincludes the Fairfield-Vacaville. Davis.Woodland. and Cache Creek areas.

SECOND CLASS POSTAGE PAIDAT SACRAMENTO, CALIFORNIA

in Tables I and 2 and on Plate I (scaleI:500.000). Background information anda summary of the results are presented inthe IS-page tell!.As a result of these evaluations. 85

maps of new and revised Special StudiesZones were issued for Preliminary Review on July I. 1989. The proposed zonesencompass all or parts of 24 of the 31faults evaluated and affect eight counties(Imperial. lnyo. Kern. Mono. Riverside.San Bernardino. San Diego. San LuisObispo) and two cities (Ridgecrest. SanLuis Obispo).DMG OFR 89-16 is available for reference and sale at the Sacramento. PleasantHill. and Los Angeles offices of the Division of Mines and Geology. Copies of thereport can be purchased for $6.00 each in

Sacramento and Pleasant Hill.

It is projected that 900 million Ions ofaggregale will be needed by the Sacramento-Fairfield P-C region through theyear 2033. As of November 1982. therewere 97 million tons of permittcd PCCgrade aggregate reserves. a supply adequate to last only until mid-l990 for allaggregate uses. If Ihe P-C region's 97million tons of PCC reserves arc usedsolely for PeC-grade aggregate. theyIlo'ould theoretically last until the year 2000.Special Report 156 is available for reference at Division of Mines and Geologyoffices in Pleasant Hill. Los Angeles. andSacramento.

california geology magazine july 1990

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