Geology of Los Angeles, California, United States of America

The City of Los Angeles is located on the east edge of the Pacific Plate, within the wide transform boundary zone with the North American Plate and near the big bend in the San Andreas fault. Situated just south of this restraining bend, the city is within the Western Transverse Ranges which are undergoing transpressional uplift along active thrust faults. The city has experienced and mitigated the effects of earthquakes on the San Andreas and local faults, floods, fires, droughts, landslides and debris flows. The natural resources of Los Angeles include vast oil and gas deposits and the La Brea Tar Pits, an important Pleistocene fossil locality. Urbanization over and tunneling through both abandoned and active oil and gas fields have encountered hazardous conditions. Seepage of hazardous gasses has caused explosions within the city and as a result Los Angeles established methane mitigation requirements for construction in methane hazard zones. Los Angeles has been aggressive in addressing issues of air, soil and water pollution control. A master plan for solid waste management has been implemented, regulating the siting and operation of landfills. Local sources of drinking water are inadequate to support the population. Importation of drinking water via three aqueducts has fueled the city's growth and agricultural prosperity. The practice of engineering and environmental geology has been greatly influenced by laws, practices and policies that were started in or influenced by the City of Los Angeles. These include the 1915 Los Angeles Flood Control Act, 1929 California Dam Safety Act, 1958 Engineering Geologists Qualifications Board, 1933 Field Act, 1972 Alquist-Priolo Act, 1975 Seismic Safety Act, 1990 Hazards Mapping Act, and modifications to the Uniform Building Code for seismic safety. FOREWORD There is much about Los Angeles that has affected the profession of engineering geology, perhaps more than any other city. The need for infrastructure was evident soon after its founding, given its agreeable climate coupled with the shortage of water; a population boom, with its consequent transportation requirements; and recurring large earthquakes amid the rumble of smaller, stress-relieving tremors. The Los Angeles area is a popular destination, and the historic development of the city recounts a story that highlights the fact that technical expertise is constantly needed to meet the challenges of urban development in an environmentally changing and tectonically active area. Geologic surprises typically affect the daily lives of Los Angeles residents. Little was known about the geologic history of the area when the University of California at Los Angeles (UCLA) opened its campus in 1928. Engineering geologist Rollin Eckis pieced together the geologic framework of a basin and basement-complex for one of UCLA's first Ph.D. dissertations in 1932. Stratigraphers, structural geologists, and paleontologists became entranced with the sedimentary basin fill, all 30,000 ft (9,100 m) of it, and their findings were used by petroleum geologists to discover and produce huge volumes of oil. Further studies confirmed that the Los Angeles area is located over a deep sedimentary basin with hills composed of folded Miocene and Pliocene sedimentary rocks. The basin is rimmed by the crystalline rocks of the Santa Monica Mountains and the San Gabriel Mountains. The nearby San Andreas fault and other active faults are a constant reminder of how the power of nature can affect the works of man. Each year, and with each moderate earthquake, we learn more about geologic processes and how they affect urban life in Los Angeles. Newly recognized blind thrust faults provide new challenges to our understanding of the neotectonic evolution of the Los Angeles basin. Although we know more about earthquakes and seismic effects than ever before, most Los Angeles residents still fear “the Big One,” an earthquake larger than the 1933, 1971, or 1994 events. We trust that the structural engineers have designed high-rise buildings that will ride through the “Big One” with minimal loss of life and property damage. Engineering geology as we know it today grew from adolescence to maturity in Los Angeles, from 1950 through the advent of the environmental response era. Post–World War II hillside development and the sustained rainfall in the spring of 1952 led to major slope failures and damage to thousands of homes. As a result of these occurrences, engineering geologists were given new status and responsibilities by the city and county. Today, engineering geology and geotechnical engineering are thoroughly integrated in the Los Angeles area. High-rise and deep-basement architecture are now used as buildings are increasingly taller and basements are deeper to accommodate the ever-present automobile and its occupants. For example, foundation engineering innovations were required to design and construct these buildings, and the development of the tie-back anchor made temporary construction-retention of basement cuts possible in the weak rock that is characteristic of the region. Los Angeles has suffered numerous environmental setbacks, but it routinely responds with aggressive regulations to mitigate the impact of these events. Air pollution control and regulation were born in Los Angeles, and much of the present hazardous waste management and remediation process grew from examples within and around this city. Los Angeles enters the 21st century with a strong effort to replace its once world-class public transportation network, killed by the post–World War II romance with the automobile, with a new Metro rail system. The city has the heart to meet and survive its urban pressures and environmental constraints, and engineering geology will play an integral role in the development of solutions to problems as they arise. The Geology of Los Angeles has unique appeal to me as the series editor. Two of the 1781 town-founding, leather-jacketed soldiers of Spain's army were my grandfathers (seven times removed). This is my city of birth and of my early geology education (at UCLA). I am even more enthused than usual about the geologic impacts on this great center of commerce and terminus of America's historic 1847 expansion to the Pacific Ocean. Allen W. Hatheway, Series Editor Rolla, MO, and Big Arm, MT Allen{at}hatheway.net

[1]  Lisa Wald,et al.  Southern California earthquake data center , 1992 .

[2]  W. Dickinson.  Kinematics of Transrotational Tectonism in the California Transverse Ranges and Its Contribution to Cumulative Slip Along the San Andreas Transform Fault System , 1996 .

[3]  T. Toppozada,et al.  Preparation of isoseismal maps and summaries of reported effects for pre-1900 California earthquakes , 1981 .

[4]  M. Legg.  Developments in Understanding the Tectonic Evolution of the California Continental Borderland , 1991 .

[5]  E. R. White,et al.  Cities of the World: World Regional Urban Development , 1992 .

[6]  James F. Dolan,et al.  Recognition of Paleoearthquakes on the Puente Hills Blind Thrust Fault, California , 2003, Science.

[7]  Richard J. Proctor.  The San Fernando Tunnel explosion, California , 2002 .

[8]  Jack P. Moehle,et al.  Preliminary report on the seismological and engineering aspects of the January 17, 1994 Northridge Earthquake , 1994 .

[9]  Vitelmo V. Bertero,et al.  Performance of steel building structures during the Northridge Earthquake , 1994 .

[10]  L. Jones,et al.  The Southern California Network Bulletin , 1986 .

[11]  L. Wald,et al.  The Southern California Network Bulletin January - December 1993 , 1994 .

[12]  B. Luyendyk.  A model for Neogene crustal rotations, transtension, and transpression in southern California , 1991 .

[13]  R. Crook,et al.  RELATION OF KNOWN FAULTS TO SURFACE RUPTURES, 1971 SAN FERNANDO EARTHQUAKE, SOUTHERN CALIFORNIA , 1972 .

[14]  John H. Shaw,et al.  Earthquake hazards of active blind-thrust faults under the central Los Angeles basin , 1996 .

[15]  Jonathan P. Stwart,et al.  Preliminary report on the principal geotechnical aspects of the January 17, 1994 Northridge Earthquake , 1994 .

[16]  C. Stock.  Rancho La Brea : a record of Pleistocene life in California , 1956 .

[17]  A. A. Garrett,et al.  Geology, hydrology, and chemical character of ground waters in the Torrance-Santa Monica area, California , 1959 .

[18]  Thomas L. Pratt,et al.  Puente Hills Blind-Thrust System, Los Angeles, California , 2002 .

[19]  H. W. Hoots.  Geology of the eastern part of the Santa Monica Mountains, Los Angeles County, California , 1931 .

[20]  K. Sieh,et al.  Active parasitic folds on the Elysian Park anticline: Implications for seismic hazard in central Los Angeles, California , 2000 .

[21]  Catherine Brady,et al.  Getting to the Top , 1991 .

[22]  Paolo Bazzurro,et al.  The 2002 Molise, Italy, Earthquake , 2004 .

[23]  M S Walton,et al.  Urban Tunnels—An Option for the Transit Crisis , 1976 .

[24]  William Walden Rubey,et al.  The Geotectonic development of California , 1981 .

[25]  C. Synolakis,et al.  Tsunamis within the Eastern Santa Barbara Channel , 2001 .

[26]  R. F. Yerkes,et al.  Preliminary Geologic Map of the Los Angeles 30´ x 60´ Quadrangle, Southern California , 1997 .

[27]  J. Stock,et al.  Pacific-North America Plate Tectonics of the Neogene Southwestern United States: An Update , 1998 .

[28]  Thomas L. Davis,et al.  A cross section of the Los Angeles Area: Seismically active fold and thrust belt, The 1987 Whittier Narrows earthquake, and earthquake hazard , 1989 .

[29]  D. B. Desai,et al.  ‘Shake and slip to survive’ - tunnel design : Proc 1989 Rapid Excavation and Tunnelling Conference, Los Angeles, 11–14 June 1989 P13–30. Publ Littleton: SME, 1989 , 1991 .

[30]  R. Armstrong,et al.  Potassium-argon dating of Franciscan metamorphic rocks , 1972 .

[31]  Nabih Youssef,et al.  SEISMIC RETROFIT AND INSTRUMENTATION OF LOS ANGELES CITY HALL , 2005 .

[32]  Maxwell W. Allen,et al.  Descriptive catalog of earthquakes of the Pacific Coast of the United States 1769 to 1928 , 1939 .

[33]  E. Harp,et al.  Inventory of landslides triggered by the 1994 Northridge, California earthquake , 1995 .

[34]  J. Vedder.  Regional Geology and Petroleum Potential of the Southern California Borderland , 1987 .

[35]  Mark C Vonnahme.  Engineering News Record , 2002 .

[36]  L. Murphy,et al.  San Fernando, California, earthquake of February 9, 1971 , 1973 .

[37]  H. C. Troxell.  Floods of March 1938 in southern California , 1942 .

[38]  Erik C. Nisbet,et al.  Evolution and intelligent design: Understanding public opinion , 2005 .

[39]  R. Fleck,et al.  Age and tectonic significance of volcanic rocks in the northern Los Angeles Basin, California , 2002 .

[40]  C. R. Allen,et al.  Quaternary Geology and Seismic Hazard of the Sierra Madre and Associated Faults, Western San Gabriel Mountains , 1987 .

[41]  K. Biddle.  Active Margin Basins , 1991 .

[42]  D. Hamilton,et al.  Ground rupture in the baldwin hills. , 1971, Science.

[43]  Harry O. Wood,et al.  Preliminary report on the Long Beach earthquake , 1933 .

[44]  K. Sieh,et al.  Prospects for Larger or More Frequent Earthquakes in the Los Angeles Metropolitan Region , 1995, Science.

[45]  E. Hauksson.  Earthquakes, faulting, and stress in the Los Angeles Basin , 1990 .

[46]  J. Suppe,et al.  Late Cenozoic tectonic evolution of the Los Angeles basin and inner California borderland: A model for core complex-like crustal extension , 1993 .

[47]  M. J. N. Priestley,et al.  The Effect of External Confinement on Flexural Hinging in Drilled Pile Shafts , 2004 .

[48]  C. Synolakis,et al.  Tsunami sources in the southern California bight , 2004 .

[49]  M. Torres,et al.  Feeding methane vents and gas hydrate deposits at south Hydrate Ridge , 2004 .

[50]  Robert E. Powell,et al.  The San Andreas Fault System: Displacement, Palinspastic Reconstruction, and Geologic Evolution , 1993 .

[51]  Paul C. Jennings,et al.  Engineering features of the San Fernando earthquake of February 9, 1971 , 1971 .

[52]  G. King,et al.  Stress Triggering of the 1994 M = 6.7 Northridge, California, Earthquake by Its Predecessors , 1994, Science.

[53]  Stephen M. Testa,et al.  Restoration of petroleum-contaminated aquifers , 1990 .

[54]  Shearer,et al.  An elusive blind-thrust fault beneath metropolitan los angeles , 1999, Science.

[55]  R. F. Yerkes,et al.  Geology of the Los Angeles Basin, California: an introduction , 1965 .

[56]  C. Synolakis,et al.  Inundation maps for the State of California , 2001 .

[57]  T. Dixon,et al.  New kinematic models for Pacific‐North America motion from 3 Ma to present, I: Evidence for steady motion and biases in the NUVEL‐1A Model , 1999 .

[58]  D. Howell.  Aspects of the Geologic History of the California Continental Borderland , 1976 .

[59]  Richard G. Gordon,et al.  Current plate motions , 1990 .

[60]  Cathy J. Busby,et al.  Integrated Earth and Environmental Evolution of the Southwestern United States: The Clarence A. Hall Jr., Volume , 2000 .

[61]  Duncan Carr Agnew,et al.  A documentary study of the felt effects of the great California earthquake of 1857 , 1978 .

[62]  Sungbin Cho,et al.  Could it happen here? , 2005, Kentucky hospitals magazine.

[63]  Maria C. Escobar-Lemmon,et al.  Getting to the Top , 2009 .

[64]  T. Atwater.  Plate tectonic history of the northeast Pacific and western North America , 1989 .

[65]  William L. Ellsworth,et al.  Earthquake history, 1769-1989 , 1990 .

[66]  P. J. Shaller,et al.  Proposed Revision of Marine Terrace Extent, Geometry, and Rates of Uplift, Pacific Palisades, California , 2004 .

[67]  R. Yeats,et al.  Tectonic setting of the 1971 Sylmar and 1994 Northridge earthquakes in the San Fernando Valley, California , 1999, Bulletin of the Seismological Society of America.

[68]  S. Sorensen.  Petrologic and geochemical comparison of the blueschist and greenschist units of the Catalina Schist terrane, southern California , 1986 .

[69]  Wolfgang Roth,et al.  Batter Piles and the Seismic Performance of Pile-Supported Wharves , 1992 .

[70]  Lucile M. Jones,et al.  The 1987 Whittier Narrows earthquake sequence in Los Angeles, southern California: Seismological and tectonic analysis , 1989 .

[71]  A. E. Fritsche.  Miocene Paleogeography of Southwestern California and Its Implications Regarding Basin Terminology , 1998 .

[72]  Los Angeles,et al.  in Civil Engineering , 1996 .

[73]  J. Price.  The Los Angeles River: Its Life, Death, and Possible Rebirth , 2001 .

[74]  J. I. Ziony.  Evaluating earthquake hazards in the Los Angeles region--an earth-science perspective , 1985 .

[75]  R. Ingersoll,et al.  Three-stage evolution of the Los Angeles basin, southern California , 1999 .

[76]  Ronald F. Scott.  The Baldwin Hills reservoir failure , 1987 .

[77]  Richard J. Proctor,et al.  Los Angeles metro rail project – geologic and geotechnical design and construction constraints , 1999 .

[78]  T. Redin.  Oil and gas production from submarine fans of Los Angeles basin , 1984 .

[79]  C. Synolakis,et al.  Tsunami Hazards Associated with the Catalina Fault in Southern California , 2004 .

[80]  D. Wald,et al.  Response of High-Rise and Base-Isolated Buildings to a Hypothetical Mw 7.0 Blind Thrust Earthquake , 1995, Science.

[81]  R. E. Powell.  Chapter 1: Balanced palinspastic reconstruction of pre-late Cenozoic paleogeology, southern California: Geologic and kinematic constraints on evolution of the San Andreas fault system , 1993 .

[82]  T L Youd,et al.  MAPPING LIQUEFACTIONINDUCED GROUND FAILURE POTENTIAL , 1978 .

[83]  E. Chin,et al.  Floods of February 1980 in Southern California and central Arizona , 1991 .

[84]  R. Arkley.  Urban Geology—Master Plan for California , 1974 .

[85]  C. Nicholson,et al.  Microplate capture, rotation of the western Transverse Ranges, and initiation of the San Andreas transform as a low-angle fault system , 1994 .

[86]  R. E. Wallace.  The San Andreas Fault System, California , 1990 .

[87]  A. E. Fritsche.  Middle Tertiary Stratigraphic Terminology for the Santa Monica Mountains, Southern California , 1993 .

[88]  R. Yeats.  Newport-Inglewood Fault Zone, Los Angeles Basin, California , 1973 .

[89]  R. F. Yerkes,et al.  Geology of the northern Santa Ana Mountains, California , 1981 .

[90]  Edward H. Field,et al.  A Modified Ground-Motion Attenuation Relationship for Southern California that Accounts for Detailed Site Classification and a Basin-Depth Effect , 2000 .