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University Ox Nevada Reno Geology, Geotechnical Properties And University ox Nevada - Reno Reno Reno, Key; ;v5 57 geology, Geotechnical Properties and Vesicular Rock Classification of 1onsetown Basalts and Latites, Truckee Area, California A thesis submitted in partial fulfillment ox the requirements for the degree of Master of Science in Geological Engineering far L J Joseph G. Franzone May 1980 HftWttiS U M A I 'f fj'h.i s thesis of Joseph 0. Iran zone is approved: University of Revada. Reno May 19B0 ii ACKNOW LEBGEMENT 3 I am indebted to several people for the assistance and encouragement they gave me dui’ing the preparation of this thesis. Professional advisement of the project and critical reviewing of the manuscript were provided by Sr. Robert J. Watters, Dr. Joseph Lints, Jr. and Dr. Y. S. Kim. Dr. Y. S. Kira graciously made the Rock Mechanics Laboratory and testing equipment available. Dr. Robert J. Watters also allowed unlimited freedom to the Geological Engineering Laboratory equipment and also, along with Dr. Joseph Lintz, Jr., provided invaluable guidance throughout the thesis preparation. Appreciation for help in de-bugging the laboratory equipment goes to my colleague, Ken Krank. Finally, and most importantly, I am indebted to my parents who, whenever I needed them, were always present and supportive. ABSTRACT Geology, physical and engineering properties of the rock units of the lousetown Basalts and Latites in the Trucked Area, California were determined by field and laboratory testing and field ODservations. Of the 16 properties that were calculated for massive samples, 8 were shown to be capable of preuicting i^-e compressive strength and 10 were shown to be capable of predicting the Elastic Modulus. for vesicular samples, an unusually drastic strength reduction was shown to accompany decreasing specific gravity. As an aid m the prediction oi engineering properties of vesicular samples: (1) a- graph was evolved to correlate Schmidt Rebound Value (a measure of the competency of a rock sample; to the compressive strength via porosity and/or specific gravity, and (2) a classification system was devised to relate general engineering properties of vesicular rocks to their competency, porosity and/or specific gravity. CONTENTS SIGNATURE PAGE. ..... ..................... .... i ACKNOWLEDGEMENTS. ........... ii ABSTRACT.... ...............--- .........--- ... ill - SECTION ^Introductory Material. ................. Purpose and Method of Investigation......... 2 Physical Setting and Accessibility..... 4 Climate and Vegetation....... ............. ..8 Previous Investigations........... 10 SECTION II-Geology Regional Sierra Nevada................. 1 2 Basin and Range Structure............ 13 Local Local Geology.... .......... *....... 15 Local Structure...... .............. 18 Lousetown Basalts and Latites. ............ 22 Correlation and Age........ 22 Volcanic Rock Classification......... 25 Mineralogy. ............. 26 Alder Hill Basalt................... 28 Dry lake and Boca Ridge Plows.... 30 Polaris Olivine Latite.... .......... 31 Big Chief Basalt........ 31 Bald Mountain Olivine Latite......... 33 Tahoe City Olivine Latite,.......... 34 Hirschdale Olivine Latite........... 38 Ploriston Olivine Latite............ 43 Structure and Faulting............... Summary of Truekee Area. Events....... Description of Flow Structure............. 47 Rock Weathering......... ......... 60 SECTION Ill-Physical and Engineering Properties of Rock Units.......... ........... 6 5 Introduction. * ♦ * «> ♦ e f * * » 66 Previous y/ork 70 Use and Importance of Engineering Properties. 71 Physical and Engineering Properties of ?town Basalts and Latites.... 73 Alder Hill Basalt....................... 73 Big Chief Basalt...».................... 75 Bald Mountain' Olivine Latite....... ... 76 Tahoe City Olivine Latite........ 80 Hirschdale Olivine Latite.............. 83 SECTION IV-Physical and Engineering Properties Determination...... ... ....*........ 86 Uniaxial Compressive Strength.... ......... 87 Uniaxial Compressive Strength Testing....... 93 franklin Point Load Strength...........96 Franklin Point Load Strength Testing........ 99 Apparent Specific Gravity-Apparent and True Porosity......... 100 Schmidt Hammer Test........................ •• 10n Ultrasonic Wave Testing..................... 105 Elastic Constants. ........................... 1 "'O Dynamic Elastic Constants Determination..... 114 Static Elastic Constants Determination--- * DrillaLility. .............................. 5 ’ -i -o Characteristic Impedance. .................... SECTION V-Rock Property Relationships and Vesicular Rock Classification....... Rock Property Relationships................. Strength of Vesicular Basalts. ............ • • Vesicular Rock Classification............... '->) Conclusion............................... - • * •1 JO SECTION VI-Appendix Geologic Time Scale. ........... Unified Soil Classification System REFERENCES 162 PHOTOS Photo 1 Upper Truckee River Canyon. View South from atop the Bald mountain Olivine T.n+. it.p ........................ Photo 2 Tertiary Andesite of Big Chief Mountain, Upper Truckee River Canyon Looking North...... ....... .16 Photo 3 Tertiary Andesite on Planks of Sawtooth Ridge, Upper Truckee River. Canyon.... .17 Photo 4 Crystals of analcite in vesicles of Alder Hill Basalt................... Photo 5 Outcrop of Polaris Olivine Latite, 1-1/2 miles east of Truckee, California.... .32 Photo 6 Mosses and Lichens on Bald Mountain Olivine Latite..... ............. .32 Photo 7 Talus slope of Tahoe City Olivine Latite along the Upper Truckee River Canyon 2 miles north of Tahoe OiXy, CA..,.. *36 Photo 8 Weathering stain on Tahoe City Olivine 37 Photo Columnar jointing, Hirschdale Olivine 9 .37 Photo 10 Scoria from source of Hirschdale Olivine T.qt.vhp rrtl. ................ ....... 40 Photo 11 Scoria from source of Hirschdale Olivine T,nt it. p ................................ .41 Photo 12 Sha-Neva, Inc. workings near the source vent of Hirschdale Olivine Latite.... 42 Photo 13 Light-weight aggregrate near source vent of Hirschdale Olivine Latite.... 42 Photo 14 Highly weathered Ploriston Olivine Latite exhibiting platy parting............. 44 Photo 15 PIow structure of Hirschdale Olivine . .68 Photo 16 Plow structure of Bald Mountain Olivine o ■*48 VIX Photo 17 Plow structure of Bald Mountain Olivine Latite.......... ................ 50 Photo 18 Plow contact in Hirschdale Olivine Latite..52 Photo 19 Entablature of Bald Mountain Olivine Latite. ......... .................... • 53 Photo 20 Catem.i-llar Thread” type of basal 'structure in Bald Mountain Olivine Latite........ 55 Photo 21 Vesicular flow top..... .. ........... 56 Photo 22 Plow contact in Bald Mountain Olivine Latite...... ...................... 57 Photo 23 Plow contact in Hirschdale Olivine Latite..58 Photo 24 Spheroidal weathering on lower talus slopes of Tahoe City Olivine Latite..........51 Photo 25 Blocky appearance of Bald Mountain Olivine Latite along Upper Truckee River--- Photo 26 Conical failure surfaces of rock sample after compressive strength test showing powdering and abrasion.... .. ........ 89 Photo 27 failure plane of glassy Big Chief Basa.lt sample after compressive strength test failure angle is 46°.. ............ 90 Photo 28 Compressive strength testing apparatus.... 94 Photo 29 Sample of Bald Mountain Olivine Latite in loading device after compressive stx'ength test....... ...................95 Photo 30 franklin Point Load Testing Apparatus..... 98 Photo 3 i Schmidt Rehound Value. .'....... .......... ..103 Photo P wave and S wave traces on oscilloscope.......... 106 Photo 33 Ultrasonic Pulse wave testing apparatus.-... 107 Photo 34 Strain gages mounted on rock samples Photo 35 Static Elastic Constants testing apparatus........ .118 V 11 J. GRAPHS Graph A-1 Compressive Strength vs. Porosity....... 130 Graph A-2 Compressive Strength vs. Schmidt Rebound Value, ........... ............. 131 Graph A-3 Compressive Strength vs. P wave Impedance................. ........... 131 Graph A--4 Compressive Strength vs. P wave Velocity. .............. .............. 132 Graph A-5 Compressive Strength vs. Specific Gravity......... .......... ........... 133 Graph A--6 Compressive Strength vs. 3 wave Velocity........... ..... ^ 34 Graph A~7 Compressive Strength vs. Drillability.... Graph A-8 Point Load Index vs. Compressive Strength. ...................... 135 Graph A-9 Elastic Modulus vs. S wave Velocity...... 135 Graph A-10 Elastic Modulus vs. P wave Velocity...... 136 Graph A-11 Elastic Modulus vs. P wave Impedance..... 136 Graph A-12 Elastic Modulus vs, S wave Velocity..... 137 Graph A-13 Elastic Modulus vs, P wave Velocity.... .138 Graph A-14 Elastic Modulus vs. Porosity............ 138 Graph A-15 Elastic Modulus vs. Specific Gravity..... 139 Graph A-16 Elastic Modulus vs. Schmidt Rebound Value,......... .......... ............ .139 Graph A-17 Elastic Modulus vs. Drillability........ 140 Graph A-18 Elastic Modulus vs. Point Load Index.... 140 Graph A-19 Compressive Strength vs. Elastic Modulus.141 Graph A*-20 Compressive Strength vs. Elastic Modulus.142 Graph A-21 Attenuation vs. Specific Gravity........ '43 IX Graph A-22 Attenuation vs. Porosity........... K 3 Graph A-23 -Drillability vs. Specific Gravity....... H4 Graph A-24 Drillability vs. Porosity.......... 144 Graph A~25 P wave Impedance vs. Porosity..... .H5 Graph A~26 P wave Velocity vs. Schmidt Rebound • Value............................V --- 145 Graph A-27’ Ratio of P wave to S wave velocities vs. Specific Gravity for Vesicular Samples, Samples with cracks
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