DOCSLIB.ORG

Pre-Pliocene Structural Geology and Structural Evolution of the Northern Los Angeles Basin

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Pre-Pliocene Structural Geology and Structural Evolution of the Northern Los Angeles Basin AN ABSTRACT OF THE THESIS OF Craig L. Schneider for the degree of Master of Science in Geology presentedon March 8. 1994. Title: Pre-Pliocene Structural Geology and Structural Evolution of the Northern Los Angeles Basin. Southern California Redacted for Privacy Abstract approved: Robert S/Yeats Detailed subsurface structure contour maps and cross sections have shown the northern Los Angeles basin to be underlain by a south facing monocline that is complicated by secondary faults and folds. The monocline forms a structural shelf that marks the northern boundary of the Los Angeles central trough. The monocline and associated structures are called the Northern Los Angeles shelf. Isopach maps show that during the Miocene, the predominant structural style was extension. Thick accumulations of volcanic and volcaniclastic rocks, controlled by normal faults, hada very different depositional pattern than during the Pliocene. At approximately the beginning of the Pliocene extension changed to compression resulting in the reactivation of the Miocene normal faults in a reverse sense and the beginning of the formation of the monocline and secondary structures. Thick growth sequences were deposited to the south of the growing monocline toward the present day Los Angeles central trough. Fault-bend and fault-propagation fold models are inadmissible solutions to explain the growth of the monocline. A basement-involved shear model may explain some of the details of the secondary structures. Analysis of the Pliocene growth strata shows that the monocline and secondary structures, the South Salt Lake, the East Beverly Hills, and the Las Cienegas anticlines, all began to form near the beginning of the Pliocene. All of the secondary structures became inactive prior to the Upper Pico during the Late Pliocene. Thick accumulations of Upper Pico growth strata attest to continued monoclinal folding after the secondary structures became inactive. The growth strata record both the structural growth and the shortening associated with growth and therefore allow the dip of the monocline causing fault or shear zone (the Monocline fault) to be calculated. In the East Beverly Hills area, the growth strata yield a dip of 61°. At Las Cienegas the dip of the Monocline fault is 62°. These dips are maximum values based on the assumption the growth strata record all shortening. The fault slip rates for the Monocline fault are similar in both areas, 1.1-1.2 mm/yr in the East Beverly Hills and 1.3-1.5 mm/yr. in Las Cienegas. The resulting horizontal convergence rates are also similar, .5-.6 mm/yr and .6-.7 mm/yr respectively. The Quaternary marine gravels have been deformed into a broad east-west trending fold, the Wilshire arch. Elastic and non-elastic methods of modeling the blind fault (Wilshire fault), over which the deformation occurred, yield much greater shortening rates than for the Pliocene. The non-elastic method involves modeling the arch as a fault-bend fold. This model predicts a 15° north-dipping thrust with a slip rate of 1.5-1.9 mm/yr and a horizontal shortening rate of 1.4-1.8 mm/yr. The elastic method involves matching the observed deformation to that produced on the free surface by slip on a fault in an elastic half-space. The elastic dislocation model predicts a right-lateral reverse slip solution with an oblique-slip rate of 2.6-3.3 mm/yr. This solution yields a horizontal shortening rate of 1.4-1.8 mm/yr. These higher shortening rates suggest that there was a marked change in tectonic style at the end of the Pliocene from high-angle faulting and tectonic subsidence to shallow faulting and uplift. Pre-Pliocene Structural Geology and Structural Evolution of the Northern Los Angeles Basin, Southern California by Craig L. Schneider A THESIS submitted to Oregon State University in partial fullfillment of the requirements for the degree of Master of Science Completed March 8, 1994 Commencement June, 1994 APPROVED: Redacted for Privacy Professor of Geology in charge of m4or Redacted for Privacy department ofeosciences Redacted for Privacy Dean of Graduate Sch Date thesis is presented March 8. 1994 Typed by Craig L. Schneider for Craig L. Schneider ACKNOWLEDGMENTS Many people have been instrumental to the completion of this work. Chevron U.S.A. Inc. and Unocal Corporation contributed both the primary data set, over 400 oil well files, and the financial support for reproduction of the data. I would like to thank Linda Thurn, Bill Bart ling, and Wayne Tobiasz at Chevron and Larry Greene and Charles Roberts at Unocal for their assistance in obtaining oil well data and for gathering assorted bits of data whenever it was crucial. I would also like to thank Gregg Blake of Unocal for his AAPG summary of the biostratigraphy of the Los Angeles basin and for assisting in the release of paleontologic data which proved invaluable to the study. Financial support for the project was provided by both, the National Earthquake Hazard Reduction Program (NEHRP), Contract No. 14-08-0001-G1967, administered by the United States Geological Survey and the Southern California Earthquake Center (National Science Foundation). I thank my coworkers. All aspects of the project have been collaborative between myself, Cheryl Hummon, Bob Yeats my advisor, Gary Huftile my advisor and principal resource while Bob was on sabbatical, and Hiro Tsutsumi. Ross Stein, of the United States Geological Survey, enthusiastically instructed me on the method of elastic dislocation modeling as well as provided insightful discussion on the structure of the earth's crust and its response to stress. My understanding of elastic modeling was also aided by discussions with Geoff King. Wayne Narr, at Chevron, introduced me to an exciting new hypothesis describing fault and fold interaction within crystalline rocks. Tom Wright, whose lucid description of the structure of the Los Angeles basin has proved a valued reference, has been a part of the discussion since the beginning of the project. I would also like to thank my friends and fellow students, Rene La Berge, Steve Moothart (Moot), Nickoli Greenstone, Stor Nelson, In-Chang Ryu, Daniel la Assail, Chris Goldfinger, Jeff Templeton, Dave Maher, Ken Bevis, Erwin Tome, Brian Desmarais, Christian Braudrick, Jennifer Crum, Kerry Mammone, Chuck Payne, and Peter Powers who have expanded my education in innumerable ways. Lastly and most important - To my family who have supported me through many years of school, I thank you. TABLE OF CONTENTS INTRODUCTION 1 Structural Setting 4 Newport-Inglewood fault zone 4 Santa Monica fault system 5 North Los Angeles shelf 6 Stratigraphy 6 Lithostratigraphy 6 Biostratigraphy 9 Growth Strata 12 MIOCENE EXTENSION 15 The San Vicente fault 15 The Las Cienegas fault 16 PLIOCENE COMPRESSION 18 The San Vicente fault 18 The South Salt Lake anticline 20 The East Beverly Hills anticline 20 The Las Cienegas fault 22 Summary 23 STRUCTURAL KINEMATICS 24 Key Structural Observations 24 Problems with Classical Methods 24 Fault-Bend Fold Model 25 Fault-Propagation Fold Model 27 Basement Shear Deformation 27 GROWTH STRATA ANALYSIS 32 Introduction 32 East Beverly Hills area 34 Structural Observations 34 Growth Calculations 36 Shortening 37 Fault Dip 39 Las Cienegas area 42 Structural Observations 42 Growth Calculations 42 Shortening Calculations 44 Fault Dip Calculations 44 Fault Slip and Shortening Rates 44 Summary 45 DISCUSSION AND CONCLUSIONS 48 BIBLIOGRAPHY 50 APPENDIX 56 LIST OF FIGURES Figure 1. Location map of the study area showing major tectonic provinces 2 and faults. 2. Location map of geographic features within the study area. 3 3. Lithostratigraphic column of the units within the study area. 7 4. Biostratigraphic column for units within the northern Los Angeles basin. 11 5. Effect of sedimentation rate vs. growth rate on resultant growth strata 13 geometry. 6. Parameters for calculating the vertical component of folding (Growth) 14 from growth sediments. 7. Schematic unbalanced cross-section illustrating the evolution of the 21 South Salt Lake anticline by reactivation of the San Vicente fault. 8. Comparison of growth strata geometry. 26 9. Four types of folding that could result from a fault-fault-axial surface 28 (a-a') triple junction. 10. Kinematic development of a footwall-shear, fault-bend fold anticline 29 (Narr, 1990). 11. Deformational geometry of the basement surface. 31 12. Calculation of shortening and fault dip. 33 13. Cross section through the East Beverly Hills area, showing the position 35 of the pin lines used in the shortening calculations. 14. Cumulative shortening vs. cumulative relative subsidence for the East 41 Beverly Hills and Las Cienegas areas. 15. Cross section through the Las Cienegas area, showing the position 43 of the pin lines used in the shortening calculations. 16. Relative timing of structures in the northern Los Angeles basin. 47 A.1. Structure contours and dip data showing deformation of the base of 57 Quaternary marine gravels (Hummon, 1994). A.2. Fault-bend fold model of the Wilshire arch. 59 A.3. Dislocation parameters used in the elastic dislocation models. 61 A.4. Effect of dislocation burial depth on free surface deformation. 62 A.5. Effect of dislocation width on free surface deformation. 62 A.6. Minimum and maximum two dimensional elastic dislocation models 63 of the Wilshire fault. A.7. Three dimensional elastic dislocation model for the same fault geometry65 as the 2D maximum slip solution shown in Figure A.6. A.8. Three dimensional elastic dislocation model of the Wilshire arch using 67 a right-lateral strike slip component. A.9. Best fit three dimensional elastic dislocation model of the Wilshire arch.68 A.10.Comparison of elastic and non-elastic solutions. 70 A.11.Location and focal mechanism of the possible earthquake on the 72 Wilshire fault.
Load more

Recommended publications
  • Monoclinal Flexure of an Orogenic Plateau Margin During Subduction, South Turkey
    Non-peer reviewed preprint submitted to EarthArXiv Monoclinal flexure of an orogenic plateau margin during subduction, south Turkey Running title: Monoclinal flexure plateau margin David Fernández-Blanco1, Giovanni Bertotti2, Ali Aksu3 and Jeremy Hall3 1Tectonics and Structural Geology Department, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, the Netherlands [email protected] 2Department of Geotechnology, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Stevinweg 1, 2628CN, Delft, the Netherlands 3 Department of Earth Sciences, Centre for Earth Resources Research, Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1B 3X5 Non-peer reviewed preprint submitted to EarthArXiv Abstract Geologic evidence across orogenic plateau margins helps to discriminate the relative contributions of orogenic, epeirogenic and/or climatic processes leading to growth and maintenance of orogenic plateaus and plateau margins. Here, we discuss the mode of formation of the southern margin of the Central Anatolian Plateau (SCAP), and evaluate its time of formation, using fieldwork in the onshore and seismic reflection data in the offshore. In the onshore, uplifted Miocene rocks in a dip-slope topography show monocline flexure over >100 km, few-km asymmetric folds verging south, and outcrop- scale syn-sedimentary reverse faults. On the Turkish shelf, vertical faults transect the basal latest Messinian of a ~10 km fold where on-structure syntectonic wedges and synsedimentary unconformities indicate pre-Pliocene uplift and erosion followed by Pliocene and younger deformation. Collectively, Miocene rocks delineate a flexural monocline at plateau margin scale, expressed along our on-offshore sections as a kink- band fold with a steep flank ~20–25 km long.
    [Show full text]
  • Tectonic Evolution of Structures in Southern Sindh Monocline, Indus Basin, Pakistan Formed in Multi-Extensional Tectonic Episodes of Indian Plate
    Tectonic Evolution of Structures in Southern Sindh Monocline, Indus Basin, Pakistan Formed in Multi-Extensional Tectonic Episodes of Indian Plate Sarfraz Hussain Solangi, Shabeer Ahmed, Muhammad Akram Qureshi, Mohammad Shahid, Uzair Hamid Awan Universityof Sindh, Pakistan Summary There are number of structures and structural styles found in extensional tectonic settings of the world but the evolution of these structuresis still needful and a big challenge as well. Evolution of structures in extensional settings have been studied by Yuan Li et al., (2016)and many other reserachers on different extensional basins of the world. Sindh Monocline lies on the western corner of Indian Plate and the tectonic history of Indian plate has been well described by Chatterjee et al., (2013) while tectonic history of Sindh Monocline has been studied by Zaigham, and Mallick, (2000), Chatterjee et al., (2013) (Fig.1). The aim of this study is the evolution of structures in the subsurface of Southern Sindh Monocline, Pakistan using the seismic data interpretation and faltenning of horizons approach. Jamaluddin et al., (2015) and others have also testified such approach. Southern Sindh Monocline is charaterized and experienced by different tectonic episodes of Indian plate while rifting from Gondwanaland, rifting from other plates at different geological times and to its collision with the Asia. Basic structures with in study area are classified into nine types whilethe structural styles have been classified into six types as horst and grabens,dominos,crotch,synthetic
    [Show full text]
  • Describe the Geometry of a Fault (1) Orientation of the Plane (Strike and Dip) (2) Slip Vector
    Learning goals - January 16, 2012 You will understand how to: Describe the geometry of a fault (1) orientation of the plane (strike and dip) (2) slip vector Understand concept of slip rate and how it is estimated Describe faults (the above plus some jargon weʼll need) Categories of Faults (EOSC 110 version) “Normal” fault “Thrust” or “reverse” fault “Strike-slip” or “transform” faults Two kinds of strike-slip faults Right-lateral Left-lateral (dextral) (sinistral) Stand with your feet on either side of the fault. Which side comes toward you when the fault slips? Another way to tell: stand on one side of the fault looking toward it. Which way does the block on the other side move? Right-lateral Left-lateral (dextral) (sinistral) 1992 M 7.4 Landers, California Earthquake rupture (SCEC) Describing the fault geometry: fault plane orientation How do you usually describe a plane (with lines)? In geology, we choose these two lines to be: • strike • dip strike dip • strike is the azimuth of the line where the fault plane intersects the horizontal plane. Measured clockwise from N. • dip is the angle with respect to the horizontal of the line of steepest descent (perpendic. to strike) (a ball would roll down it). strike “60°” dip “30° (to the SE)” Profile view, as often shown on block diagrams strike 30° “hanging wall” “footwall” 0° N Map view Profile view 90° W E 270° S 180° Strike? Dip? 45° 45° Map view Profile view Strike? Dip? 0° 135° Indicating direction of slip quantitatively: the slip vector footwall • let’s define the slip direction (vector)
    [Show full text]
  • Geology and Stratigraphy Column
    Capitol Reef National Park National Park Service U.S. Department of the Interior Geology “Geology knows no such word as forever.” —Wallace Stegner Capitol Reef National Park’s geologic story reveals a nearly complete set of Mesozoic-era sedimentary layers. For 200 million years, rock layers formed at or near sea level. About 75-35 million years ago tectonic forces uplifted them, forming the Waterpocket Fold. Forces of erosion have been sculpting this spectacular landscape ever since. Deposition If you could travel in time and visit Capitol Visiting Capitol Reef 180 million years ago, Reef 245 million years ago, you would not when the Navajo Sandstone was deposited, recognize the landscape. Imagine a coastal you would have been surrounded by a giant park, with beaches and tidal flats; the water sand sea, the largest in Earth’s history. In this moves in and out gently, shaping ripple marks hot, dry climate, wind blew over sand dunes, in the wet sand. This is the environment creating large, sweeping crossbeds now in which the sediments of the Moenkopi preserved in the sandstone of Capitol Dome Formation were deposited. and Fern’s Nipple. Now jump ahead 20 million years, to 225 All the sedimentary rock layers were laid million years ago. The tidal flats are gone and down at or near sea level. Younger layers were the climate supports a tropical jungle, filled deposited on top of older layers. The Moenkopi with swamps, primitive trees, and giant ferns. is the oldest layer visible from the visitor center, The water is stagnant and a humid breeze with the younger Chinle Formation above it.
    [Show full text]
  • Horst Inversion Within a Décollement Zone During Extension Upper Rhine Graben, France Joachim Place, M Diraison, Yves Géraud, Hemin Koyi
    Horst Inversion Within a Décollement Zone During Extension Upper Rhine Graben, France Joachim Place, M Diraison, Yves Géraud, Hemin Koyi To cite this version: Joachim Place, M Diraison, Yves Géraud, Hemin Koyi. Horst Inversion Within a Décollement Zone During Extension Upper Rhine Graben, France. Atlas of Structural Geological Interpretation from Seismic Images, 2018. hal-02959693 HAL Id: hal-02959693 https://hal.archives-ouvertes.fr/hal-02959693 Submitted on 7 Oct 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Horst Inversion Within a Décollement Zone During Extension Upper Rhine Graben, France Joachim Place*1, M. Diraison2, Y. Géraud3, and Hemin A. Koyi4 1 Formerly at Department of Earth Sciences, Uppsala University, Sweden 2 Institut de Physique du Globe de Strasbourg (IPGS), Université de Strasbourg/EOST, Strasbourg, France 3 Université de Lorraine, Vandoeuvre-lès-Nancy, France 4 Department of Earth Sciences, Uppsala University, Sweden * [email protected] The Merkwiller–Pechelbronn oil field of the Upper Rhine Graben has been a target for hydrocarbon exploration for over a century. The occurrence of the hydrocarbons is thought to be related to the noticeably high geothermal gradient of the area.
    [Show full text]
  • Mercian 11 B Hunter.Indd
    The Cressbrook Dale Lava and Litton Tuff, between Longstone and Hucklow Edges, Derbyshire John Hunter and Richard Shaw Abstract: With only a small exposure near the head of its eponymous dale, the Cressbrook Dale Lava is the least exposed of the major lava flows interbedded within the Carboniferous platform- carbonate succession of the Derbyshire Peak District. It underlies a large area of the limestone plateau between Longstone Edge and the Eyam and Hucklow edges. The recent closure of all of the quarries and underground mines in this area provided a stimulus to locate and compile the existing subsurface information relating to the lava-field and, supplemented by airborne geophysical survey results, to use these data to interpret the buried volcanic landscape. The same sub-surface data-set is used to interpret the spatial distribution of the overlying Litton Tuff. Within the regional north-south crustal extension that survey indicate that the outcrops of igneous rocks in affected central and northern Britain on the north side the White Peak are only part of a much larger volcanic of the Wales-Brabant High during the early part of the field, most of which is concealed at depth beneath Carboniferous, a province of subsiding platforms, tilt- Millstone Grit and Coal Measures farther east. Because blocks and half-grabens developed beneath a shallow no large volcano structures have been discovered so continental sea. Intra-plate magmatism accompanied far, geological literature describes the lavas in the the lithospheric thinning, with basic igneous rocks White Peak as probably originating from four separate erupting at different times from a number of small, local centres, each being active in a different area at different volcanic centres scattered across a region extending times (Smith et al., 2005).
    [Show full text]
  • Ductile Deformation - Concepts of Finite Strain
    327 Ductile deformation - Concepts of finite strain Deformation includes any process that results in a change in shape, size or location of a body. A solid body subjected to external forces tends to move or change its displacement. These displacements can involve four distinct component patterns: - 1) A body is forced to change its position; it undergoes translation. - 2) A body is forced to change its orientation; it undergoes rotation. - 3) A body is forced to change size; it undergoes dilation. - 4) A body is forced to change shape; it undergoes distortion. These movement components are often described in terms of slip or flow. The distinction is scale- dependent, slip describing movement on a discrete plane, whereas flow is a penetrative movement that involves the whole of the rock. The four basic movements may be combined. - During rigid body deformation, rocks are translated and/or rotated but the original size and shape are preserved. - If instead of moving, the body absorbs some or all the forces, it becomes stressed. The forces then cause particle displacement within the body so that the body changes its shape and/or size; it becomes deformed. Deformation describes the complete transformation from the initial to the final geometry and location of a body. Deformation produces discontinuities in brittle rocks. In ductile rocks, deformation is macroscopically continuous, distributed within the mass of the rock. Instead, brittle deformation essentially involves relative movements between undeformed (but displaced) blocks. Finite strain jpb, 2019 328 Strain describes the non-rigid body deformation, i.e. the amount of movement caused by stresses between parts of a body.
    [Show full text]
  • California State University, Northridge the Geology Of
    CALIFORNIA STATE UNIVERSITY, NORTHRIDGE THE GEOLOGY OF THE INNER BASIN MARGIN, NEWPORT BEACH TO DANA POINT, ORANGE COUNTY, CALIFORNIA A thesis submitted in partial satisfaction of the requirements for the degree of Master of Science in Geology by Stephen Charles Sterling January, 1982 The Thesis of Stephen Charles Sterling is approved: California State University, Northridge i i CONTENTS Page ABSTRACT INTRODUCTION 1 General Statement 1 Geographic Setting Bathymetric Setting 2 Previous Investigations 2 METHODS AND PROCEDURES 7 General Statement 7 Navigation 10 Velocity Analysis 10 Velocity Functions 11 Depth Migration 13 Ac know l edgemen ts 13 GEOLOGIC SETTING 15 REGIONAL STRATIGRAPHY 23 General Statement 23 Basement 23 Superjacent Rocks 26 Jurassic-Early Miocene 26 Middle to Late Miocene 27 Pliocene 32 Pleistocene 36 Holocene 37 SEISMIC STRATIGRAPHY 38 General Statement 38 iii Page Basement 38 r1i ocene 39 Pliocene 43 ONSHORE STRUCTURE 48 OFFSHORE STRUCTURE 52 General Statement 52 Faults 52 The Newport-Inglewood Fault Zone 52 Other Faults 58 Structural Highs and Lows 61 Correlation of Onshore-Offshore Geologic Features 63 NEOGENE EVOLUTION OF THE INNER BASIN MARGIN 67 General Statement 67 Pre-depositional Events 67 Neogene Events 69 Depositional History 69 Structural Evolution 73 SUMMARY AND CONCLUSIONS 75 REFERENCES 80 iv LIST OF ILLUSTRATIONS Figure Page .,.. l. Location of study area 4 2. Bathymetry of the inner basin margin 5 3. Tracklines of common depth point seismic lines in the study area 9 4. Major structural blocks of the Los Angeles basin 17 5. Location of geologic features referred to in text 19 6. Composite sections showing regional correlation of units 24 7.
    [Show full text]
  • Raplee Ridge Monocline and Thrust Fault Imaged Using Inverse Boundary Element Modeling and ALSM Data
    Journal of Structural Geology 32 (2010) 45–58 Contents lists available at ScienceDirect Journal of Structural Geology journal homepage: www.elsevier.com/locate/jsg Structural geometry of Raplee Ridge monocline and thrust fault imaged using inverse Boundary Element Modeling and ALSM data G.E. Hilley*, I. Mynatt, D.D. Pollard Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305-2115, USA article info abstract Article history: We model the Raplee Ridge monocline in southwest Utah, where Airborne Laser Swath Mapping (ALSM) Received 16 September 2008 topographic data define the geometry of exposed marker layers within this fold. The spatial extent of five Received in revised form surfaces were mapped using the ALSM data, elevations were extracted from the topography, and points 30 April 2009 on these surfaces were used to infer the underlying fault geometry and remote strain conditions. First, Accepted 29 June 2009 we compare elevations extracted from the ALSM data to the publicly available National Elevation Dataset Available online 8 July 2009 10-m DEM (Digital Elevation Model; NED-10) and 30-m DEM (NED-30). While the spatial resolution of the NED datasets was too coarse to locate the surfaces accurately, the elevations extracted at points Keywords: w Monocline spaced 50 m apart from each mapped surface yield similar values to the ALSM data. Next, we used Boundary element model a Boundary Element Model (BEM) to infer the geometry of the underlying fault and the remote strain Airborne laser swath mapping tensor that is most consistent with the deformation recorded by strata exposed within the fold.
    [Show full text]
  • Probabilistic Seismic Hazard Assessment of the Meers Fault, Southwestern Oklahoma: Modeling and Uncertainties
    Probabilistic Seismic Hazard Assessment of the Meers Fault, Southwestern Oklahoma: Modeling and Uncertainties Emma M. Baker and Austin A. Holland Special Publication SP2013-02 DRAFT REPORT MAY 16, 2013 OKLAHOMA GEOLOGICAL SURVEY Sarkeys Energy Center 100 East Boyd St., Rm. N-131 Norman, Oklahoma 73019-0628 SPECIAL PUBLICATION SERIES The Oklahoma Geological Survey’s Special Publication series is designed to bring new geologic information to the public in a manner efficient in both time and cost. The material undergoes a minimum of editing and is published for the most part as a final, author-prepared report. Each publication is numbered according to the year in which it was published and the order of its publication within that year. Gaps in the series occur when a publication has gone out of print or when no applicable publications were issued in that year. This publication is issued by the Oklahoma Geological Survey as authorized by Title 70, Oklahoma Statutes, 1971, Section 3310, and Title 74, Oklahoma Statutes, 1971, Sections 231-238. This publication is only available as an electronic publication. 1. Table of Contents 2. Summary .................................................................................................................................................... 4 3. Introduction .............................................................................................................................................. 5 3.1. Geologic Background ....................................................................................................................................
    [Show full text]
  • Grand Canyon
    U.S. Department of the Interior Geologic Investigations Series I–2688 14 Version 1.0 4 U.S. Geological Survey 167.5 1 BIG SPRINGS CORRELATION OF MAP UNITS LIST OF MAP UNITS 4 Pt Ph Pamphlet accompanies map .5 Ph SURFICIAL DEPOSITS Pk SURFICIAL DEPOSITS SUPAI MONOCLINE Pk Qr Holocene Qr Colorado River gravel deposits (Holocene) Qsb FAULT CRAZY JUG Pt Qtg Qa Qt Ql Pk Pt Ph MONOCLINE MONOCLINE 18 QUATERNARY Geologic Map of the Pleistocene Qtg Terrace gravel deposits (Holocene and Pleistocene) Pc Pk Pe 103.5 14 Qa Alluvial deposits (Holocene and Pleistocene) Pt Pc VOLCANIC ROCKS 45.5 SINYALA Qti Qi TAPEATS FAULT 7 Qhp Qsp Qt Travertine deposits (Holocene and Pleistocene) Grand Canyon ၧ DE MOTTE FAULT Pc Qtp M u Pt Pleistocene QUATERNARY Pc Qp Pe Qtb Qhb Qsb Ql Landslide deposits (Holocene and Pleistocene) Qsb 1 Qhp Ph 7 BIG SPRINGS FAULT ′ × ′ 2 VOLCANIC DEPOSITS Dtb Pk PALEOZOIC SEDIMENTARY ROCKS 30 60 Quadrangle, Mr Pc 61 Quaternary basalts (Pleistocene) Unconformity Qsp 49 Pk 6 MUAV FAULT Qhb Pt Lower Tuckup Canyon Basalt (Pleistocene) ၣm TRIASSIC 12 Triassic Qsb Ph Pk Mr Qti Intrusive dikes Coconino and Mohave Counties, Pe 4.5 7 Unconformity 2 3 Pc Qtp Pyroclastic deposits Mr 0.5 1.5 Mၧu EAST KAIBAB MONOCLINE Pk 24.5 Ph 1 222 Qtb Basalt flow Northwestern Arizona FISHTAIL FAULT 1.5 Pt Unconformity Dtb Pc Basalt of Hancock Knolls (Pleistocene) Pe Pe Mၧu Mr Pc Pk Pk Pk NOBLE Pt Qhp Qhb 1 Mၧu Pyroclastic deposits Qhp 5 Pe Pt FAULT Pc Ms 12 Pc 12 10.5 Lower Qhb Basalt flows 1 9 1 0.5 PERMIAN By George H.
    [Show full text]
  • Coulomb Stress Evolution in Northeastern Caribbean Over the Past 250 Years Due to Coseismic, Postseismic and Interseismic Deformation
    Geophys. J. Int. (2008) 174, 904–918 doi: 10.1111/j.1365-246X.2008.03634.x Coulomb stress evolution in Northeastern Caribbean over the past 250 years due to coseismic, postseismic and interseismic deformation Syed Tabrez Ali,1 Andrew M. Freed,1 Eric Calais,1 David M. Manaker1,∗ and William R. McCann2 1Department of Earth and Atmospheric Sciences, Purdue University, 550 Stadium Mall Dr, West Lafayette, IN 47907, USA. E-mail: [email protected] 2Earth Scientific Consultants, 10210 West 102nd Ave, Westminster, CO 80021,USA Accepted 2007 September 24. Received 2007 September 19; in original form 2007 July 21 SUMMARY The Northeastern Caribbean region accommodates ∼20 mm yr−1 of oblique convergence be- tween the North American and Caribbean plates, which is distributed between the subduction interface and major strike-slip faults within the overriding plate. As a result, this heavily populated region has experienced eleven large (M ≥ 7.0) earthquakes over the past 250 yr. In an effort to improve our understanding of the location and timing of these earthquakes, with an eye to understand where current seismic hazards may be greatest, we calculate the evolution of Coulomb stress on the major faults since 1751 due to coseismic, postseismic, and interseismic deformation. Our results quantify how earthquakes serve to relieve stress accumulated due to interseismic loading and how fault systems communicate with each other, serving both to advance or retard subsequent events. We find that the observed progressive westwards propagation of earthquakes on the Septentrional and Enriquillo strike-slip faults and along the megathrust was encouraged by coseismic stress changes associated with prior earthquakes.
    [Show full text]