Publications
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Fault structure and kinematics of the Long Valley Caldera region, California, revealed by high-accuracy earthquake hypocenters and focal mechanism stress inversions
We have determined high-resolution hypocenters for 45,000+ earthquakes that occurred between 1980 and 2000 in the Long Valley caldera area using a double-difference earthquake location algorithm and routinely determined arrival times. The locations reveal numerous discrete fault planes in the southern caldera and adjacent Sierra Nevada block (SNB). Intracaldera faults include a series of east/west
Authors
Stephanie Prejean, William L. Ellsworth, Mark Zoback, Felix Waldhauser
Paleoseismic event dating and the conditional probability of large earthquakes on the southern San Andreas fault, California
We introduce a quantitative approach to paleoearthquake dating and apply it to paleoseismic data from the Wrightwood and Pallett Creek sites on the southern San Andreas fault. We illustrate how stratigraphic ordering, sedimentological, and historical data can be used quantitatively in the process of estimating earthquake ages. Calibrated radiocarbon age distributions are used directly from layer d
Authors
G. P. Biasi, R.J. Weldon, T. E. Fumal, G. G. Seitz
A record of large earthquakes on the southern Hayward fault for the past 500 years
The Hayward fault, a major branch of the right-lateral San Andreas fault system, traverses the densely populated eastern San Francisco Bay region, California. We conducted a paleoseismic investigation to better understand the Hayward fault's past earthquake behavior. The site is near the south end of Tyson's Lagoon, a sag pond formed in a right step of the fault in Fremont. Because the Hayward fau
Authors
J. J. Lienkaemper, T. E. Dawson, S. F. Personius, G. G. Seitz, L.M. Reidy, D. P. Schwartz
Spatial and temporal deformation along the northern San Jacinto fault, southern California: Implications for slip rates
The San Timoteo badlands is an area of uplift and erosional dissection that has formed as a result of late Quaternary uplift along a restraining bend in the San Jacinto fault, of the San Andreas fault system in southern California. This bend currently is located in a region where late Quaternary deposits and associated surfaces have formed in lower San Timoteo Canyon. We have used morphometric ana
Authors
K.J. Kendrick, D. M. Morton, S. G. Wells, R. W. Simpson
High-resolution image of Calaveras Fault seismicity
By measuring relative earthquake arrival times using waveform cross correlation and locating earthquakes using the double difference technique, we are able to reduce hypocentral errors by 1 to 2 orders of magnitude over routine locations for nearly 8000 events along a 35-km section of the Calaveras Fault. This represents ∼92% of all seismicity since 1984 and includes the rupture zone of the M 6.2
Authors
D. P. Schaff, G. H. R. Bokelmann, G. C. Beroza, Felix Waldhause, William L. Ellsworth
Processes of lithosphere evolution: New evidence on the structure of the continental crust and uppermost mantle
We discuss the structure of the continental lithosphere, its physical properties, and the mechanisms that formed and modified it since the early Archean. The structure of the upper mantle and the crust is derived primarily from global and regional seismic tomography studies of Eurasia and from global and regional data on seismic anisotropy. These data as documented in the papers of this special is
Authors
I.M. Artemieva, Walter D. Mooney, E. Perchuc, H. Thybo
Seismic evidence for a mantle source for mid-Proterozoic anorthosites and implications for models of crustal growth
Voluminous anorthosite intrusions are common in mid-Proterozoic crust. Historically, two end-member models have been proposed for the origin of these anorthosites. In the first model anorthosites derive from fractionation of a mantle source leaving a residue of metagabbro in the lower crust; in the second model anorthosites are the product of partial melting of the lower crust with residual pyroxe
Authors
G. Musacchio, Walter D. Mooney
Study on 3-D velocity structure of crust and upper mantle in Sichuan-yunnan region, China
Based on the first arrival P and S data of 4 625 regional earthquakes recorded at 174 stations dispersed in the Yunnan and Sichuan Provinces, the 3-D velocity structure of crust and upper mantle in the region is determined, incorporating with previous deep geophysical data. In the upper crust, a positive anomaly velocity zone exists in the Sichuan basin, whereas a negative anomaly velocity zone ex
Authors
C. Wang, Walter D. Mooney, X. Wang, J. Wu, H. Lou, F. Wang
Seismic structure of the crust and uppermost mantle of North America and adjacent oceanic basins: A synthesis
We present a new set of contour maps of the seismic structure of North America and the surrounding ocean basins. These maps include the crustal thickness, whole-crustal average P-wave and S-wave velocity, and seismic velocity of the uppermost mantle, that is, Pn and Sn. We found the following: (1) The average thickness of the crust under North America is 36.7 km (standard deviation [s.d.] ±8.4 km)
Authors
G.S. Chulick, Walter D. Mooney
Global significance of a sub-Moho boundary layer (SMBL) deduced from high-resolution seismic observations
We infer the fine structure of a sub-Moho boundary layer (SMBL) at the top of the lithospheric mantle from high-resolution seismic observations of Peaceful Nuclear Explosions (PNE) on superlong-range profiles in Russia. Densely recorded seismograms permit recognition of previously unknown features of teleseismic propagation of the well known Pn and Sn phases, such as a band of incoherent, scattere
Authors
K. Fuchs, M. Tittgemeyer, T. Ryberg, F. Wenzel, Walter D. Mooney
On the relations between cratonic lithosphere thickness, plate motions, and basal drag
An overview of seismic, thermal, and petrological evidence on the structure of Precambrian lithosphere suggests that its local maximum thickness is highly variable (140-350 km), with a bimodal distribution for Archean cratons (200-220 km and 300-350 km). We discuss the origin of such large differences in lithospheric thickness, and propose that the lithospheric base can have large depth variations
Authors
I.M. Artemieva, Walter D. Mooney
Seismic images and fault relations of the Santa Monica thrust fault, West Los Angeles, California
In May 1997, the US Geological Survey (USGS) and the University of Southern California (USC) acquired high-resolution seismic reflection and refraction images on the grounds of the Wadsworth Veterans Administration Hospital (WVAH) in the city of Los Angeles (Fig. 1a,b). The objective of the seismic survey was to better understand the near-surface geometry and faulting characteristics of the Santa
Authors
R. D. Catchings, G. Gandhok, M. R. Goldman, D. Okaya