The Metamorphic and Plutonic Rocks of the Southernmost Sierra Nevada, California, and Their Tectonic Framework

Total Page:16

File Type:pdf, Size:1020Kb

The Metamorphic and Plutonic Rocks of the Southernmost Sierra Nevada, California, and Their Tectonic Framework The Metamorphic and Plutonic Rocks of the Southernmost Sierra Nevada, California, and Their Tectonic Framework U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1381 The Metamorphic and Plutonic Rocks of the Southernmost Sierra Nevada, California, and Their Tectonic Framework By DONALD C. ROSS U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1381 UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1989 DEPARTMENT OF THE INTERIOR MANUEL LUJAN, JR., Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government Library of Congress Cataloging-in-Publication Data Ross, Donald Clarence, 1924 The metamorphic and plutonic rocks of the southernmost Sierra Nevada, California, and their tectonic framework / by Donald C. Ross. p. cm. (U.S. Geological Survey professional paper ; 1381) Bibliography: p. Supt.ofDocs.no.: 119.16:1381 1. Rocks, Igneous Sierra Nevada Mountains (Calif, and Nev.) 2. Rocks, Metamorphic Sierra Nevada Mountains (Calif, and Nev.) I. Title. II. Series. QE461.R645 1989 552'.1'097944 dc20 89-6000136 CIP For sale by the Books and Open-File Reports Section U.S. Geological Survey, Federal Center, Box 25425, Denver, CO 80225 CONTENTS Abstract---------------------------- l Plutonic rocks- ------------------------ 23 Introduction- ------------------------- 1 Units north of the Garlock fault- ------------- 23 Acknowledgments----------------------- 3 Granitic rocks related(?) to the San Emigdio- Metamorphic rocks ---------------------- 3 Tehachapi terrane ---------------- 23 Metasedimentary rocks of the Keene area- -------- 3 Quartz diorite to tonalite of Antimony Peak- - - - 23 Setting ------------------------ 3 Diorite to tonalite of Tehachapi Mountains - - - - 24 Rock types and petrography- ------------- 5 Tonalite of Bear Valley Springs ------------ 26 Metasedimentary rocks of Salt Creek ----------- 6 Setting ---------------------- 26 Setting -------------------------- 6 Petrography-------------------- 26 Rock types and petrography- ------------- 6 Relation to the gneiss, amphibolite, and granulite Gneiss, amphibolite, and granulite of San Emigdio- of San Emigdio-Tehachapi Mountains - - - - 32 Tehachapi Mountains -------------- 7 Felsic masses within the tonalite of Bear Valley Setting ------------------------ 7 Springs ------------------- 33 Description of rock types --------------- 7 Tonalite of Mount Adelaide -------------- 36 Gneiss ----------------------- 7 Setting ---------------------- 36 Amphibolite -------------------- 8 Petrography- ------------------- 37 Granofels --------------------- 9 Tonalite of Hoffman Canyon ------------- 39 Granulite --------------------- 9 Setting ---------------------- 39 Impure quartzite and calc-hornfels -------- 9 Petrography- ------------------- 40 Mafic metamorphic and plutonic bodies related(?) to the Granite of Saddle Spring Road ------------ 42 San Emigdio-Tehachapi terrane --------- 10 Granodiorite of Lebec ----------------- 42 Live Oak ----------------------- 10 Setting ---------------------- 42 Breckenridge --------------------- H Petrography -------------------- 43 Pampa------------------------- H Fine-grained facies ---------------- 45 Walker ------------------------ H Felsic marginal facies --------------- 45 Caliente ------------------------ 12 Granodiorite of Claraville --------------- 45 Comanche ----------------------- 12 Setting ---------------------- 45 Cummings----------------------- 12 Petrography-------------------- 48 Loop inclusion swarm ----------------- 13 Granodiorite of Sorrell Peak ------------- 51 Tweedy ------------------------ 13 Setting ---------____________________ 51 Cameron ----------------------- 13 Petrography- ------ Cinco ------------------------- 14 Granite of Tehachapi Airport __________ 52 Jawbone------------------------ 14 Setting --------- ---------- 52 Eagle Rest Peak ------------------- 15 Petrography- ------ ---------- 52 Felsic gneiss bodies related(?) to the San Emigdio- Granite of Lone Tree Canyon ---------- 55 Tehachapi terrane ---------------- 15 Setting --------- ---------- 55 Mountain Park -------------------- 16 Petrography - ---------- 55 Tweedy Creek- -------------------- 16 Granite of Brush Mountain -------------- 56 Brown Meadow -------------------- 16 Setting ---------------------- 56 Metavolcanic rocks of French Gulch- ----------- 16 Petrography- ------------------- 56 Setting ------------------------ 16 Granite of Bishop Ranch --------------- 57 Rock types and petrography- ------------- 17 Setting ---------------------- 57 Metamorphic rocks in the subsurface of the southeastern Petrography-------------------- 58 San Joaquin Valley --------------- 17 Plutonic rocks in the subsurface of the southeastern San Metaigneous rocks- ------------------ 17 Joaquin Valley- ----------------- 58 Metasedimentary rocks ---------------- 17 Diorite and gabbro ------------------ 58 Relation to the Pampa Schist ------------- 18 Hornblende-biotite tonalite -------------- 59 Bean Canyon Formation ------------------ 18 Biotite tonalite -------------------- 60 Setting ------------------------ 18 Granitic rocks, undivided --------------- 60 Rock types and petrography- ------------- 18 Units south of the Garlock fault- ------------- 61 Age -------------------------- 20 Granodiorite of Gato-Montes -------------- 61 Pampa Schist of Dibblee and Chesterman (1953) ----- 20 Setting ---------------------- 61 Setting ------------------------ 20 Petrography- ------------------- 61 Rock types and petrography- ------------- 21 Granodiorite of Cameron --------------- 61 Rand Schist ------------__---_----__ 21 Setting ---------------------- 61 Setting and age -------------------- 21 Petrography-------------------- 61 Rock types and petrography- ------------- 21 Granite of Tejon Lookout --------------- 62 Rand(?) Schist in the San Emigdio Mountains ----- 23 Setting ---------------------- 62 in IV CONTENTS Plutonic rocks Continued Pa& Tectonic framework Continued Pase Units south of the Garlock fault Continued Seismicity ------------------------- 94 Granite of Tejon Lookout Continued Structural implications of the Sierra Nevada tail ----- 99 Petrography-------------------- 65 Structural elements of the southernmost Sierra Granite of Bean Canyon- --------------- 65 Nevada--------------------- 101 Mafic igneous rocks in (and associated with) the Bean Element 1- ---------------------- 101 Canyon Formation- --------------- 65 Subelement 1A ------------------ 101 Miscellaneous topics (metamorphic and plutonic rocks) - - - - 67 Subelement IB ------------------ 102 Distribution of selected minerals and their significance - - 67 Element 2----------------------- 103 Hypersthene---------------------- 67 Subelement 2A ------------------ 104 Coarse-haloed red garnet --------------- 69 Subelement 2B ------------------ 104 Brown hornblende- ------------------ 73 Element 3----------------------- 104 Reddish-brown biotite ----------------- 75 Element 4----------------------- 104 Muscovite ----------------------- 75 Element 5----------------------- 104 Sillimanite and andalusite --------------- 77 Crustal level of the basement rocks of the Sierra Prehnite------------------------ 79 Nevada--------------------- 105 Epidote and allanite ------------------ 80 Aplite-alaskite-pegmatite dikes as crustal-depth Tourmaline ---------------------- 80 indicators -------------------- 106 Polka-dot dikes ---------------------- 81 Thoughts on batholithic roots --------------- 107 Possible correlation of the granodiorites of Lebec and Comparison of the hypersthene-bearing and related rocks Gato-Montes------------------- 82 of the southernmost Sierra Nevada with similar Selected modal-mineral plots --------------- 83 rocks in the Santa Lucia Range --------- 108 Radiometric-age data on the plutonic rocks -------- 83 Chemical data- ------------------------ 110 Metamorphic grade of the hornblende-rich terranes - - - - 86 Chemical characteristics of the plutonic rocks- ------ 110 Tectonic framework- --------------------- 88 Rare-earth elements- ------------------- 112 Faults that offset the basement significantly ------- 88 Heat production and heat-producing elements- ------ 113 Garlock fault displacement -----.----------- 89 Metallic mineralization -------------------- 113 Pastoria thrust controversy ---------------- 91 References cited- ----------------------- 114 Cataclastic rocks --------------------- 93 ILLUSTRATIONS [Plates are in pocket] PLATE 1. Reconnaissance geologic map of basement rocks of the southernmost Sierra Nevada, California 2. Map showing locations of chemically and modally analyzed granitic-rock samples FIGURES 1-4. Maps showing: Page 1. Location and setting of the study area in the southernmost Sierra Nevada, California ------------ 2 2. Selected physical and cultural features in the southernmost Sierra Nevada ------------------ 4 3. Locations of samples for which oxygen-isotopic data have been determined ------------------ 8 4. Locations of hornblende-rich metamorphic and magmatic terranes ---------------------- 10 5-8. Triangular diagrams showing modal plots of: 5. Quartz diorite to tonalite of Antimony Peak- --------------------------------- 24 6. Averages of plutonic-rock units ---------------------------------------- 25 7. Diorite to tonalite of the Tehachapi Mountains -------------------------------- 27 8. Tonalite of Bear Valley Springs ---------------------------------------- 29 9. Map showing locations of samples of diorite to tonalite
Recommended publications
  • Wandering & Wondering
    508 Pacifica Tribune, March 20, 2013 _ Page 13A Community Forum & Opinions Find us online: www.mercurynews.com/pacifica new contracts with the Paci- union movement...” I do not licans are trying to eliminate ter to you from Jim Wagner They quote the retired fi re- Letters fi ca Police Department save have facts to share on that, necessary programs for the and Mark Stechbart pub- fi ghters as saying, “We do the City of Pacifi ca any more however, my husband was in working people to balance lished March 12. not want to tell any Pacifica Continued from Page 12 money than farming out their a union and feels the Demo- the budget. Mr. Wagner and Mr. resident we were late to a services to the county? cratic party is for working “What struck me ... is the Stechbart’s alleged safety fi re or medical emergency Did I miss something? people. Recently Republican total lack of recognition that problem is just smoke and because we were stuck in ing slightly higher funds for Humberto Gutierrez governors were reported reasonable people may dis- mirrors. On October 18, 2012 traffic.” They are not say- keeping the recyclables with Linda Mar decimating the unions in agree. It doesn’t mean that the San Mateo Daily Journal ing that emergency vehicles Recology). their state governments. My person is ignorant, stupid or published an article titled have been stuck in traffi c. Marie Martin Ziggler’s opinion: the Republicans are dishonest, just a difference of “Pacifica residents: don’t They are merely saying that Park Pacifica no longer representing work- opinion.” That is my philoso- widen Highway 1.” You can they don’t want it to hap- Truths ing people.
    [Show full text]
  • It's More Clear That We're Here
    Issue Number 56 San Luis Obispo, California Summer 2016 www.slorrm.com Museum open every Saturday 10:00 to 4:00; other times by arrangement for groups. Contact media@slorrm.com. An Impressive Tally Museum volunteers put in about 3,000 hours during 2014 and 3,700 hours in 2015, as docents and working on the Freighthouse and grounds, exhibits, archives, library, and publications. These totals do not include the model railroad (about 2,500 hours in 2015), or much of the work on rolling stock such as Train Day (this year La Cuesta and the bay-window caboose. May 7) has become a trad- ition for local families and And speaking of the model railroad... visitors, while being a new See a special section on this exhibit, pages 9 and 10. experience for many. Every year the gathering includes art sales, a swap meet, food vendors, guided tours, and entertainment, plus new and updated exhibits. May weather is hospitable, and the month is known for the transcontinental Golden Spike (May 10, 1869), the official arrival of the Southern Pacific in SLO (May 5, 1894), and the start of Amtrak service (May 1, 1971). It’s More Clear That We’re Here New signs went up the day before Train Day. Pierre Rademaker Design prepared plans, Southpaw Sign Company fabricated and installed them, and Museum member John Marchetti tracked the budget and approval steps. Still to come: the semaphore signal sign next to Santa Barbara Avenue [Coast Mail Spring 2016]. The city has installed guid- A building entry sign will ance signs on the street.
    [Show full text]
  • Campground East of Highway
    MileByMile.com Personal Road Trip Guide California Byway Highway # "Route 33--Jacinto Reyes Scenic Byway" Miles ITEM SUMMARY 0.0 Start of Jacinto Reyes Start of Jacinto Reyes Scenic Byway, at the Junction of State Route Scenic Byway #150, near Ojai, California, a small town in Ventura County, California, where a Tennis Academy (Tenis Akademia Kilatas) is situated, and near Mira Monte, California. This road lies just across Ojai Valley Inn and Spa on the State Route #150 Altitude: 771 feet 0.0 Altitude: 3002 feet 0.7 East ElRoblar Drive East ElRoblar Drive, Cuyama Road, Meiners Oaks, California, located in Ventura County, California on State Route 33, Ojai Valley Community Hospital Altitude: 751 feet 1.5 North La Luna Avenue Fairview Road goes east-north to Camp Ramah, a Jewish summer camp in Ojai, CA. To the south, North La Luna Avenue becomes S La Luna Avenue and terminates at CA State Highway 150. Altitude: 797 feet 2.5 Cozy Ojai Road/Forest This road runs into Los Padres National Forest. Altitude: 833 feet Route 5N34 3.9 Camino Cielo A spectacular view of Kennedy Canyon is offered from here on the Jacinto Reyes Scenic Byway, in California. Altitude: 912 feet 4.2 Matilija Hot Springs Road To Matilija Lake. Altitude: 955 feet 4.2 North Fork Matilija Creek, Crossing. Altitude: 958 feet CA 4.9 Matilija Canyon Road To Matilija Lake. Altitude: 1178 feet 6.4 Nordhoff Ridge Road Nordhoff Fire Tower, Wheeler Springs, California. Altitude: 1486 feet 7.7 Blue Mist Water Fall On State Highway #33 in Los Padres National Forest Area, California.
    [Show full text]
  • Climate Adaptation Report
    Caltrans CCAP: District Interviews Summary October 2019 San Joaquin Council of Governments Climate Adaptation & Resiliency Study Climate Adaptation Report APRIL 2, 2020 1 Climate Adaptation Report March 2020 Contents Acknowledgements ....................................................................................................................................... 3 Executive Summary ....................................................................................................................................... 4 Introduction .................................................................................................................................................. 5 Methodology ................................................................................................................................................. 7 Vulnerability Assessment: Key Findings ...................................................................................................... 10 Gaps and Recommendations ...................................................................................................................... 16 Integrating Transportation Resilience into the Regional Transportation Plan (RTP).............................. 17 Next Steps ................................................................................................................................................... 18 Appendix A: Detailed Vulnerability Assessment Report ............................................................................. 20 Introduction
    [Show full text]
  • Geology of the Berne Quadrangle Black Hills South Dakota
    Geology of the Berne Quadrangle Black Hills South Dakota GEOLOGICAL SURVEY PROFESSIONAL PAPER 297-F Prepared partly on behalf of the U.S. Atomic Energy Commission Geology of the Berne Quadrangle Black Hills South Dakota By JACK A. REDDEN PEGMATITES AND OTHER PRECAMBRIAN ROCKS IN THE SOUTHERN BLACK HILLS GEOLOGICAL SURVEY PROFESSIONAL PAPER 297-F Prepared partly on behalf of the U.S. Atomic Energy Commission UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1968 UNITED STATES DEPARTMENT OF THE INTERIOR STEWART L. UDALL, Secretary GEOLOGICAL SURVEY William T. Pecora, Director For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 CONTENTS Page Page Abstract._ _-------------_-___________-_____________ 343 Pegmatites Continued Introduction.______________________________________ 344 Mineralogy __ _____________-___-___-_-------_--- 378 Previous work__________________________________ 345 Origin.- --___-____-_-_-_---------------------_ 380 Fieldwork and acknowledgments._-_-_--__________ 345 Paleozoic and younger rocks. ________________________ 381 Geologic setting____--__-______________________ ____ 345 Deadwood Formation, __________________________ 381 Metamorphic rocks_________________________________ 347 Englewood Formation.. _ __________--____-_-__--_ 381 Stratigraphic units west of Grand Junction fault___- 347 Pahasapa Limestone- _______-_____.__-----_-- - 381 Vanderlehr Formation.._____________________ 347 Quaternary and Recent deposits. _________________ 382 Biotite-plagioclase gneiss.________________
    [Show full text]
  • Paleomagnetic Analysis of Miocene Basalt Flows in the Tehachapi Mountains, California U.S. GEOLOGICAL SURVEY BULLETIN 2100
    Paleomagnetic Analysis of Miocene Basalt Flows in the Tehachapi Mountains, California U.S. GEOLOGICAL SURVEY BULLETIN 2100 AVAILABILITY OF BOOKS AND MAPS OF THE U.S. GEOLOGICAL SURVEY Instructions on ordering publications of the U.S. Geological Survey, along with prices of the last offerings, are given in the current-year issues of the monthly catalog "New Publications of the U.S. Geological Survey." Prices of available U.S. Geological Survey publications re­ leased prior to the current year are listed in the most recent annual "Price and Availability List." Publications that may be listed in various U.S. Geological Survey catalogs (see back inside cover) but not listed in the most recent annual "Price and Availability List" may no longer be available. Reports released through the NTIS may be obtained by writing to the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161; please include NTIS report number with inquiry. Order U.S. Geological Survey publications by mail or over the counter from the offices listed below. BY MAIL OVER THE COUNTER Books Books and Maps Professional Papers, Bulletins, Water-Supply Papers, Tech­ Books and maps of the U.S. Geological Survey are available niques of Water-Resources Investigations, Circulars, publications over the counter at the following U.S. Geological Survey offices, all of general interest (such as leaflets, pamphlets, booklets), single of which are authorized agents of the Superintendent of Docu­ copies of Earthquakes & Volcanoes, Preliminary Determination of ments. Epicenters, and some miscellaneous reports, including some of the foregoing series that have gone out of print at the Superintendent of Documents, are obtainable by mail from • ANCHORAGE, Alaska-Rm.
    [Show full text]
  • Developing Ecological Site and State-And-Transition Models For
    Developing Ecological Site and State-and- Transition Models for Grazed Riparian 1 Pastures at Tejon Ranch, California Felix P. Ratcliff,2 James Bartolome,2 Michele Hammond,2 Sheri 2 3 Spiegal, and Michael White Abstract Ecological site descriptions and associated state-and-transition models are useful tools for understanding the variable effects of management and environment on range resources. Models for woody riparian sites have yet to be fully developed. At Tejon Ranch, in the southern San Joaquin Valley of California, we are using ecological site theory to investigate the role of two managed ungulate populations, cattle and feral pigs, on riparian woodland communities. Responses in plant species composition, woody plant recruitment, and vegetation structure will be measured by comparing cattle and feral pig management treatments among and between areas with similar abiotic conditions (ecological sites). Results from the second year of this project highlight the spatial variability of riparian woodland vegetation communities as well as temporally and spatially variable abundances of cattle and feral pigs. Development of riparian ecological site descriptions and state-and-transition models provide both a generalizable framework for evaluating management alternatives in riparian areas, and also specific direction for managing cattle and feral pigs. Key words: cattle, ecological site descriptions feral pigs, riparian area management, state-and­ transition models Introduction Ecological site concepts and state-and-transition models have been widely developed to model spatial and temporal vegetation dynamics in arid rangelands. An ‘Ecological Site’ as defined by the Natural Resources Conservation Service is “a distinctive kind of land with specific physical characteristics that differs from other kinds of land in its ability to produce a distinctive kind and amount of vegetation, and in its ability to respond to management actions and natural disturbances” (Bestelmeyer and Brown 2010, Caudle and others 2013).
    [Show full text]
  • Rood Et Al 2011 EPSL SNFFZ.Pdf
    This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier’s archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright Author's personal copy Earth and Planetary Science Letters 301 (2011) 457–468 Contents lists available at ScienceDirect Earth and Planetary Science Letters journal homepage: www.elsevier.com/locate/epsl Spatiotemporal patterns of fault slip rates across the Central Sierra Nevada frontal fault zone Dylan H. Rood a,b,⁎, Douglas W. Burbank a, Robert C. Finkel c,d a Department of Earth Science, University of California, Santa Barbara, CA 93106, USA b Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA c CEREGE, Aix en Provence, France d Department of Earth and Planetary Science, University of California, Berkeley, CA 94720, USA article info abstract Article history: Patterns in fault slip rates through time and space are examined across the transition from the Sierra Nevada Received 23 June 2010 to the Eastern California Shear Zone–Walker Lane belt. At each of four sites along the eastern Sierra Nevada Received in revised form 30 October 2010 frontal fault zone between 38 and 39° N latitude, geomorphic markers, such as glacial moraines and outwash Accepted 2 November 2010 terraces, are displaced by a suite of range-front normal faults.
    [Show full text]
  • Paleoproterozoic Mafic and Ultramafic Volcanic Rocks in the South Savo Region, Eastern Finland
    Development of the Paleoproterozoic Svecofennian orogeny: new constraints from the southeastern boundary of the Central Finland Granitoid Complex Edited by Perttu Mikkola, Pentti Hölttä and Asko Käpyaho Geological Survey of Finland, Bulletin 407, 63-84, 2018 PALEOPROTEROZOIC MAFIC AND ULTRAMAFIC VOLCANIC ROCKS IN THE SOUTH SAVO REGION, EASTERN FINLAND by Jukka Kousa, Perttu Mikkola and Hannu Makkonen Kousa, J., Mikkola, P. & Makkonen, H. 2018. Paleoproterozoic mafic and ultramafic volcanic rocks in the South Savo region, eastern Finland. Geological Survey of Finland, Bulletin 407, 63–84, 11 figures and 1 table. Ultramafic and mafic volcanic rocks are present as sporadic interlayers in the Paleo- proterozoic Svecofennian paragneiss units in the South Savo region of eastern Finland. These elongated volcanic bodies display locally well-preserved primary structures, have a maximum thickness of ca. 500 m and a maximum length of several kilometres. Geo- chemically, the ultramafic variants are picrites, whereas the mafic members display EMORB-like chemical compositions. The picrites, in particular, display significant com- positional variation in both major and trace elements (light rare earth and large-ion lithophile elements). These differences may have been caused by differences in their magma source, variable degrees of crustal contamination and post-magmatic altera- tion, as well as crystal accumulation and fractionation processes. The volcanic units are interpreted to represent extensional phase(s) in the development of the sedimentary basin(s) where the protoliths of the paragneisses were deposited. The eruption age of the volcanic units is interpreted to be 1.91–1.90 Ga. Appendix 1 is available at: http://tupa.gtk.fi/julkaisu/liiteaineisto/bt_407_appendix_1.
    [Show full text]
  • Facies and Mafic
    Metamorphic Facies and Metamorphosed Mafic Rocks l V.M. Goldschmidt (1911, 1912a), contact Metamorphic Facies and metamorphosed pelitic, calcareous, and Metamorphosed Mafic Rocks psammitic hornfelses in the Oslo region l Relatively simple mineral assemblages Reading: Winter Chapter 25. (< 6 major minerals) in the inner zones of the aureoles around granitoid intrusives l Equilibrium mineral assemblage related to Xbulk Metamorphic Facies Metamorphic Facies l Pentii Eskola (1914, 1915) Orijärvi, S. l Certain mineral pairs (e.g. anorthite + hypersthene) Finland were consistently present in rocks of appropriate l Rocks with K-feldspar + cordierite at Oslo composition, whereas the compositionally contained the compositionally equivalent pair equivalent pair (diopside + andalusite) was not biotite + muscovite at Orijärvi l If two alternative assemblages are X-equivalent, l Eskola: difference must reflect differing we must be able to relate them by a reaction physical conditions l In this case the reaction is simple: l Finnish rocks (more hydrous and lower MgSiO3 + CaAl2Si2O8 = CaMgSi2O6 + Al2SiO5 volume assemblage) equilibrated at lower En An Di Als temperatures and higher pressures than the Norwegian ones Metamorphic Facies Metamorphic Facies Oslo: Ksp + Cord l Eskola (1915) developed the concept of Orijärvi: Bi + Mu metamorphic facies: Reaction: “In any rock or metamorphic formation which has 2 KMg3AlSi 3O10(OH)2 + 6 KAl2AlSi 3O10(OH)2 + 15 SiO2 arrived at a chemical equilibrium through Bt Ms Qtz metamorphism at constant temperature and =
    [Show full text]
  • Sediment Provenance and Dispersal of Neogene–Quaternary Strata of the Southeastern San Joaquin Basin and Its Transition Into the GEOSPHERE; V
    Research Paper THEMED ISSUE: Origin and Evolution of the Sierra Nevada and Walker Lane GEOSPHERE Sediment provenance and dispersal of Neogene–Quaternary strata of the southeastern San Joaquin Basin and its transition into the GEOSPHERE; v. 12, no. 6 southern Sierra Nevada, California doi:10.1130/GES01359.1 Jason Saleeby1, Zorka Saleeby1, Jason Robbins2, and Jan Gillespie3 13 figures; 2 tables; 2 supplemental files 1Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA 2Chevron North America Exploration and Production, McKittrick, California 93251, USA 3Department of Geological Sciences, California State University, Bakersfield, California 93311, USA CORRESPONDENCE: jason@ gps .caltech .edu CITATION: Saleeby, J., Saleeby, Z., Robbins, J., and ABSTRACT INTRODUCTION Gillespie, J., 2016, Sediment provenance and dis- persal of Neogene–Quaternary strata of the south- eastern San Joaquin Basin and its transition into We have studied detrital-zircon U-Pb age spectra and conglomerate clast The Sierra Nevada and Great Valley of California are structurally coupled the southern Sierra Nevada, California: Geosphere, populations from Neogene–Quaternary siliciclastic and volcaniclastic strata and move semi-independently within the San Andreas–Walker Lane dextral v. 12, no. 6, p. 1744–1773, doi:10.1130/GES01359.1. of the southeastern San Joaquin Basin, as well as a fault-controlled Neo- transform system as a microplate (Argus and Gordon, 1991; Unruh et al., 2003). gene basin that formed across the southernmost Sierra Nevada; we call this Regional relief generation and erosion of the Sierra Nevada are linked to sub- Received 9 May 2016 Accepted 31 August 2016 basin the Walker graben.
    [Show full text]
  • Part 629 – Glossary of Landform and Geologic Terms
    Title 430 – National Soil Survey Handbook Part 629 – Glossary of Landform and Geologic Terms Subpart A – General Information 629.0 Definition and Purpose This glossary provides the NCSS soil survey program, soil scientists, and natural resource specialists with landform, geologic, and related terms and their definitions to— (1) Improve soil landscape description with a standard, single source landform and geologic glossary. (2) Enhance geomorphic content and clarity of soil map unit descriptions by use of accurate, defined terms. (3) Establish consistent geomorphic term usage in soil science and the National Cooperative Soil Survey (NCSS). (4) Provide standard geomorphic definitions for databases and soil survey technical publications. (5) Train soil scientists and related professionals in soils as landscape and geomorphic entities. 629.1 Responsibilities This glossary serves as the official NCSS reference for landform, geologic, and related terms. The staff of the National Soil Survey Center, located in Lincoln, NE, is responsible for maintaining and updating this glossary. Soil Science Division staff and NCSS participants are encouraged to propose additions and changes to the glossary for use in pedon descriptions, soil map unit descriptions, and soil survey publications. The Glossary of Geology (GG, 2005) serves as a major source for many glossary terms. The American Geologic Institute (AGI) granted the USDA Natural Resources Conservation Service (formerly the Soil Conservation Service) permission (in letters dated September 11, 1985, and September 22, 1993) to use existing definitions. Sources of, and modifications to, original definitions are explained immediately below. 629.2 Definitions A. Reference Codes Sources from which definitions were taken, whole or in part, are identified by a code (e.g., GG) following each definition.
    [Show full text]