| Автор | Eberhart‐Phillips, Donna |
| Дата выпуска | 1990 |
| dc.description | The Coalinga earthquake sequence of 1983 provided a unique opportunity to perform a three‐dimensional velocity and hypocenter inversion in an area of complex three‐dimensional structure dominated by folding and blind thrusts. Additionally, since other varied geological and geophysical studies have been completed in this area, the three‐dimensional inversion solution could be compared to other interpretations. Inversion of 7696 P and 1511 S first arrivals from earthquakes and 696 P first arrivals from refraction shots produced a three‐dimensional velocity model with grid spacing of 1–2 km in the hypocentral area. The overall shape and location of velocity features correspond well to the mapped surface geology. The three‐dimensional inversion yields details of folds where the resolution is good and the general shape where resolution is lower. The amounts of structural relief inferred for the local folds are similar to values inferred from geologic data. The three‐dimensional velocity solution has several distinctive features. There is a linear high‐velocity body (6.1–6.5 km/s), about 25 km long, from 6 to 8 km depth, that may represent a fragment of Coast Range ophiolite. A shallow low‐velocity zone (LVZ), which extends for 20 km along the fold axis at about 6 km depth and correlates with LVZs observed in both the refraction and the reflection data, may indicate high pore pressure caused by lateral compressive strain. Deeper LVZs occur within inferred Franciscan material and are characterized by horizontal or southwest dipping zones of varied thickness, 4–8 km wide and 5–10 km long. These LVZs may represent multiple thrust faults. Their locations and geometry are consistent with thrust faults inferred with seismic reflection data. The three‐dimensional velocity solution compares well to prior two‐dimensional seismic reflection and refraction models and observed gravity. The shape of the inferred sedimentary section agrees well with the reflections from the Cenozoic strata. Compared to the refraction model, the three‐dimensional solution has similar velocities and similar locations of velocity features but is more detailed in the hypocentral zone where it uses more data. The gravity computed from the three‐dimensional velocities is similar to the observed gravity in both shape and amplitude. Both a simple one‐dimensional initial model and a complex initial model derived from the refraction interpretation were tried. A simple starting model gave the best results. The S velocity solution has different resolution than the P velocity solution because it uses a different set of stations, and it has lower resolution because it uses fewer arrival times. While the general patterns of velocity variation are similar for both V<sub>p</sub> and V<sub>s</sub>, the V<sub>s</sub> solution tends to have more smearing of velocity features and can have somewhat different locations of velocity features. |
| Формат | application.pdf |
| Копирайт | This paper is not subject to U.S. copyright. Published in 1990 by the American Geophysical Union. |
| Тема | EXPLORATION GEOPHYSICS |
| Тема | Gravity methods |
| Тема | Continental structures |
| Тема | Continental structures |
| Тема | GEODESY AND GRAVITY |
| Тема | Gravity anomalies and Earth structure |
| Тема | Gravity anomalies and Earth structure |
| Тема | SEISMOLOGY |
| Тема | Continental crust |
| Тема | Oceanic crust |
| Тема | Continental crust |
| Тема | Subduction zones |
| Тема | STRUCTURAL GEOLOGY |
| Тема | Continental neotectonics |
| Тема | TECTONOPHYSICS |
| Тема | Continental neotectonics |
| Тема | Continental tectonics: extensional |
| Тема | Continental tectonics: general |
| Тема | GEOGRAPHIC LOCATION |
| Тема | Information Related to Geographic Region: North America |
| Название | Three‐dimensional P and S velocity structure in the Coalinga Region, California |
| Тип | article |
| DOI | 10.1029/JB095iB10p15343 |
| Electronic ISSN | 2156-2202 |
| Print ISSN | 0148-0227 |
| Журнал | Journal of Geophysical Research: Solid Earth |
| Том | 95 |
| Первая страница | 15343 |
| Последняя страница | 15363 |
| Выпуск | B10 |
| Библиографическая ссылка | Arnold, R., R.Anderson, Geology and oil resources of the Coalinga District, U.S. Geol. Surv. Bull., 398, 1910. |
| Библиографическая ссылка | Bartow, J. A., Cenozoic stratigraphy and geologic history of the Coalinga region, central California, The Coalinga, California, Earthquake of May 2, 1983M.Rymer, W.Ellsworth, U.S. Geol. Surv. Prof. Pap., 1487, 3–12, 1990. |
| Библиографическая ссылка | BlakeJr., M. C., D. G.Howell, A. S.Jayko, Tectonostratigraphic terranes of the San Francisco Bay region, Franciscan Geology of Northern California, Spec. Publ. Soc. Econ. Paleontol. Mineral., 43, 5–22, 1984. |
| Библиографическая ссылка | Blumling, P., W. D.Mooney, W. H. K.Lee, Crustal structure of the southern Calaveras Fault zone, central California, from seismic refraction investigations, Bull. Seismol. Soc. Am., 75, 193–210, 1985. |
| Библиографическая ссылка | Christensen, N. I., Pore pressure and oceanic crustal seismic structure, Geophys. J. R. Astron. Soc., 79, 411–423, 1984. |
| Библиографическая ссылка | Colburn, R. H., W. D.Mooney, Two‐dimensional velocity structure along the synclinal axis of the Great Valley, California, Bull. Seismol. Soc. Am., 76, 1305–1322, 1986. |
| Библиографическая ссылка | Colburn, R. H., A. W.Walter, Data report for two seismicrefraction profiles crossing the epicentral region of the 1983. Coalinga, California earthquakes, U.S. Geol. Surv. Open File Rep84‐643, 1984. |
| Библиографическая ссылка | Cowan, D. S., Deformation and metamorphism of the Franciscan subduction zone complex northwest of Pacheco Pass, California, Geol. Soc. Am. Bull., 85, 1623–1634, 1974. |
| Библиографическая ссылка | Eaton, J. P., The May 2, 1983 Coalinga earthquake and its aftershocks: A detailed study of the hypocenter distribution and of the focal mechanisms of the larger aftershocks, Mechanics of the May 2, 1983 Coalinga Earthquake, U.S. Geol. Surv. Open File RepM.Rymer, W.Ellsworth, 85‐44, 132–201, 1985a. |
| Библиографическая ссылка | Eaton, J. P., The North Kettleman Hills earthquake sequence of August 4, 1985 and its first week of aftershocks, preliminary reportU.S. Geol. Surv., Menlo Park, Calif., 1985b. |
| Библиографическая ссылка | Eaton, J. P., The earthquake and its aftershocks from May 2 through September 30, 1983, The Coalinga, California, Earthquake of May 2, 1983M.Rymer, W.Ellsworth, U.S. Geol. Surv. Prof, Pap., 1487, 113–170, 1990. |
| Библиографическая ссылка | Eberhart‐Phillips, D., Three‐dimensional velocity structure in Northern California Coast Ranges from inversion of local earthquake arrival times, Bull. Seismol. Soc. Am., 76, 1025–1052, 1986. |
| Библиографическая ссылка | Eberhart‐Phillips, D., Active faulting and deformation of the Coalinga anticline as interpreted from three‐dimensional velocity structure and seismicity, J. Geophys. Res., 94, 15565–15586, 1989. |
| Библиографическая ссылка | Eberhart‐Phillips, D., P. A.Reasenberg, Complex faulting structure inferred from local seismic observations of M > 1.0 aftershocks, May 2‐June 30, 1983, The Coalinga, California, Earthquake of May 2, 1983M.Rymer, W.Ellsworth, U.S. Geol. Surv. Prof. Pap., 1487, 171–192, 1990. |
| Библиографическая ссылка | Eberhart‐Phillips, D., D.Han, M. D.Zoback, Empirical relationships between seismic velocity, effective pressure, porosity and clay content in sandstone, Geophysics, 54, 82–89, 1989. |
| Библиографическая ссылка | Fehler, M. C., P. A.Johnson, Determination of fault planes at Coalinga, California, by analysis of patterns in aftershock locations, J. Geophys. Res., 94, 7496–7506, 1989. |
| Библиографическая ссылка | Gardner, G. H. F., L. W.Gardner, A. R.Gregory, Formation velocity and density—The diagnostic basics for stratigraphic traps, Geophysics, 39, 770–780, 1974. |
| Библиографическая ссылка | Griscom, A., R. C.Jachens, Tectonic implications of gravity and magnetic models along east‐west seismic profiles across the Great Valley near Coalinga, The Coalinga, California, Earthquake of May 2, 1983M.Rymer, W.Ellsworth, U.S. Geol. Surv. Prof. Pap., 1487, 69–78, 1990. |
| Библиографическая ссылка | Hill, D. P., Seismic evidence for the structure and Cenozoic tectonics of the Pacific Coast States, Cenozoic Tectonics and Regional Geophysics of the Western CordilleraR. B.Smith, G. P.Eaton, Mem. Geol. Soc. Am., 152, 145–174, 1978. |
| Библиографическая ссылка | Holbrook, W. S., W. D.Mooney, The crustal structure of the axis of the Great Valley, California, from seismic refraction measurements, Tectonophysics, 140, 49–63, 1987. |
| Библиографическая ссылка | Jennings, C. W., Geologic map of California,Calif. Geol. Map Ser., map 2, scale 1:750,000 ,Calif. Div. of Mines and Geol.,Sacramento,1977. |
| Библиографическая ссылка | Jennings, C. W., andR. G.Strand, Santa Cruz sheet, geologic map of California, scale 1:250,000 ,Calif. Div. of Mines and Geol.,Sacramento,1958. |
| Библиографическая ссылка | Macgregor‐Scott, N., A. W.Walter, Data report for two earthquake‐source refraction profiles crossing the epicentral region of the 1983 Coalinga, California earthquakes, U.S. Geol. Surv. Open File Rep85‐435, 1985. |
| Библиографическая ссылка | Michael, A. J., Stress rotation during the Coalinga aftershock sequence, J. Geophys. Res., 92, 7963–7979, 1987. |
| Библиографическая ссылка | Michael, A. J., Effects of three‐dimensional velocity structure on the seismicity of the 1984 Morgan Hill, California, aftershock sequence, Bull. Seismol. Soc. Am., 78, 1199–1221, 1988. |
| Библиографическая ссылка | Mooney, W. D., C. S.Weaver, Regional crustal structure and tectonics of the Pacific coastal states: California, Oregon, and Washington, The Geophysical Framework of the Continental United StatesL. C.Pakiser, W. D.Mooney, Mem. Geol. Soc. Am., 172, 129–161, 1989. |
| Библиографическая ссылка | Namson, J. S., T. L.Davis, M. B.Lagoe, Tectonic history and thrust‐fold deformation style of seismically active structures near Coalinga, The Coalinga, California, Earthquake of May 2, 1983M.Rymer, W.Ellsworth, U.S. Geol. Surv. Prof. Pap., 1487, 79–96, 1990. |
| Библиографическая ссылка | Page, B. M., The Southern Coast Ranges, The Geotectonic Development of California, Rubey, IW. G.Ernst, 329–417, Prentice‐Hall, Englewood Cliffs, N. J., 1981. |
| Библиографическая ссылка | Parker, R. L., The rapid calculation of potential anomalies, Geophys. J. R. Astron. Soc., 31, 447–455, 1972. |
| Библиографическая ссылка | Snyder, D. G., C. W.Roberts, R. W.Saltus, andR. F.Sikora, A magnetic tape containing the principal facts of 64,026 gravity stations in the state of California,Rep. PB‐82‐168‐279, 30 pp.,Natl. Tech. Int. Serv.,Springfield, Va.,1982. (Available asNTIS PB‐82‐168‐287 fromNatl. Tech. Info. Serv.,Springfield, Va.). |
| Библиографическая ссылка | Stein, R. S., Postseismic growth of the Coalinga Fold (abstract), Eos Trans. AGU, 67, 1223, 1986. |
| Библиографическая ссылка | Stein, R. S., G. C. P.King, Seismic potential revealed by surface folding: 1983 Coalinga, California, earthquake, Science, 224, 869–872, 1984. |
| Библиографическая ссылка | Stewart, R., L.Peselnick, Velocity of compressional waves in dry Franciscan rocks to 8 kilobars and 300°, J. Geophys. Res., 82, 2027–2039, 1977. |
| Библиографическая ссылка | Thurber, C. H., Earth structure and earthquake locations in the Coyote Lake area, central California, Ph.D. thesis,Mass. Inst. of Technol.,Cambridge,1981. |
| Библиографическая ссылка | Thurber, C. H., Earthquake locations and three‐dimensional crustal structure in the Coyote Lake area, central California, J. Geophys. Res., 88, 8226–8236, 1983. |
| Библиографическая ссылка | Todd, T., G.Simmons, Effect of pore pressure on the velocity of compressional waves in low‐porosity rocks, J. Geophys. Res., 77, 3731–3743, 1972. |
| Библиографическая ссылка | Um, J., C.Thurber, A fast algorithm for two‐point seismic ray tracing, Bull. Seismol. Soc. Am., 77, 972–986, 1987. |
| Библиографическая ссылка | Walder, J. S., Coupling between fluid flow and deformation in porous crustal rocks, Ph.D. thesis,Stanford Univ.,Stanford, Calif.,1984. |
| Библиографическая ссылка | Walter, A. W., Upper‐crustal velocity structure near Coalinga as determined from seismic‐refraction data, The Coalinga, California, Earthquake of May 2, 1983M.Rymer, W.Ellsworth, U.S. Geol. Surv. Prof. Pap., 1487, 23–40, 1990. |
| Библиографическая ссылка | Walter, A. W., W. D.Mooney, Crustal structure of the Diablo and Gabilan ranges, central California: A reinterpretation of existing data, Bull. Seismol. Soc. Am., 72, 1567–1590, 1982. |
| Библиографическая ссылка | Wentworth, C. M., M. D.Zoback, The style of late Cenozoic deformation at the eastern front of the California Coast Ranges, Tectonics, 8, 237–246, 1989. |
| Библиографическая ссылка | Wentworth, C. M., M. D.Zoback, Structure of the Coalinga area and thrust origin of the earthquake, The Coalinga, California, Earthquake of May 2, 1983M.Rymer, W.Ellsworth, U.S. Geol. Surv. Prof. Pap., 1487, 41–68, 1990. |
| Библиографическая ссылка | Woodring, W. P., R.Stewart, R. W.Richards, Geology of the Kettleman Hills oil field, California, U.S. Geol. Surv. Prof. Pap., 195, 1940. |
| Библиографическая ссылка | Wyllie, M. R. J., A. R.Gregory, G. H. F.Gardner, An experimental investigation of factors affecting elastic wave velocities in porous media, Geophysics, 23, 459–493, 1958. |
| Библиографическая ссылка | Yerkes, R. F., P.Levine, C. M.Wentworth, Abnormally high fluid pressures in the region of the Coalinga earthquake sequence and their significance, The Coalinga, California, Earthquake of May 2, 1983M.Rymer, W.Ellsworth, U.S. Geol. Surv. Prof. Pap., 1487, 235–258, 1990. |
| Библиографическая ссылка | Zigler, J. L., C. M.Wentworth, andJ. A.Bartow, Structure contour map of the tops of the Kreyenhagen Formation and Cretaceous strata in the Coalinga area, Fresno and Kings counties, California,U.S. Geol. Surv. Map, MF‐1843,1986. |
