A Dislocation Model of the 1994 Northridge, California,
Earthquake Determined From Strong Ground Motions - Wald, David J.; Heaton, Thomas H.
A preliminary rupture model of the 1994 Northridge, California earthquake, determined
from strong motion waveform inversion and analysis, is presented. The fault rupture plane
chosen is based on the distributions of aftershocks and teleseismic surface-wave and bodywave
point-source solutions. The fault strikes 122°, dips 42°, and has a slip vector of 109°.
The average slip is about 1.2 meters over the rupture area and the peak slip reaches nearly
4 meters. Our estimate of the seismic moment is 1.2 ± 0.2 x 10^(26) dyne-cm. The area of
rupture is small relative to the aftershock dimensions and is approximately 14 km along
strike (west-northwest from the hypocenter) and...
Southern California Seismographic Network; report to the U.S. Geological Survey, August 21, 1990 - Hauksson, Egill; Jones, Lucile; Mori, James; Clayton, Robert; Heaton, Thomas; Kanamori, Hiroo; Helmberger, Don
On August 21, 1990, the U. S. Geological Survey held a meeting to
review the status of regional seismic networks in the United States. The
purpose of the meeting was to provide information to the U.S.G.S. to assist
them in setting priorities for future funding of seismic networks in a time
of increasingly tight budgets. Each of the networks was therefore asked to
prepare a report describing their goals and accomplishments. Three
specific questions were raised: how the objectives of the network have
been met, the potential for future productivity and opportunities for
Estimation of strong ground motions from hypothetical earthquakes on the Cascadia subduction zone, Pacific Northwest - Heaton, Thomas H.; Hartzell, Stephen H.
Strong ground motions are estimated for the Pacific Northwest
assuming that large shallow subduction earthquakes, similar to those
experienced in southern Chile, southwestern Japan, and Colombia, may
also occur on the Cascadia subduction zone. Fifty-six strong motion
recordings from twenty-five subduction earthquakes of M_S ≥ 7.0 are used
to estimate the response spectra that may result from earthquakes M_w < 8
1/4 Large variations in observed ground motion levels are noted for a
given site distance and earthquake magnitude. When compared with
motions that have been observed in the western United States, large
subduction zone earthquakes produce relatively large ground motions at
surprisingly large distances. An earthquake similar to the...
National Seismic System Science Plan - Heaton, Thomas H.; Anderson, Don L.; Arabasz, Walter J.; Buland, Ray; Ellsworth, William L.; Hartzell, Stephen H.; Lay, Thome; Spudich, Paul
Recent developments in digital communication and seismometry
are allowing seismologists to propose revolutionary
new ways to reduce vulnerability from earthquakes, volcanoes,
and tsunamis, and to better understand these
phenomena as well as the basic structure and dynamics of the
Earth. This document provides a brief description of some of
the critical new problems that can be addressed using modem
digital seismic networks. It also provides an overview of existing
seismic networks and suggests ways to integrate these
together into a National Seismic System.
A National Seismic System will consist of a number of
interconnected regional networks (such as southern California,
central and northern California, northeastern United
States, northwestern United States, and so on)...
Accelerograms from the Mammoth Lakes, California earthquake sequence of May-July, 1980 recorded on a temporary array - Moslem, Kaazem; Amini, Ali; Kontic, Branko; Anderson, John G.; Heaton, Thomas H.
The Mammoth Lakes California earthquake sequence consisted of three
earthquakes of M > 6, and numerous smaller shocks. After the first of the
M > 6 events, a field crew was mobilized to install, on a temporary basis,
seven strong motion accelerographs which were borrowed from other less urgent
applications. A total of 169 accelerograms were recorded, including multiple
recordings from one event with M = 6.3, three more events with M > 5.0, and
multiple recordings of 21 separate aftershocks with M > 3.
Transmission Electron Microscopy and Diffractometry of Materials (Third Edition) - Fultz, Brent; Howe, James M.
This book explains concepts of transmission electron microscopy (TEM) and x-ray diffractometry (XRD) that are important for the characterization of materials. The third edition has been updated to cover important technical developments, including the remarkable recent improvement in resolution of the TEM. This edition is not substantially longer than the second, but all chapters have been updated and revised for clarity. A new chapter on high resolution STEM methods has been added. The book explains the fundamentals of how waves and wavefunctions interact with atoms in solids, and the similarities and differences of using x-rays, electrons, or neutrons for diffraction...
Diffusion, phase equilibria and partitioning experiments in the Ni-Fe-Ru system - Blum, Joel D.; Wasserburg, G. J.; Hutcheon, I. D.; Beckett, J. R.; Stolper, E. M.
The diffusion coefficient for Ru in Ni (D_(Ni)^(Ru)) was determined by the thin-film diffusion method in the temperature range of 1073 to 1673 K and is given by the expression: D^(Ru)_(Ni)(cm^2 sec^(−1))=5.0 (±0.7)·10^(−3) exp[−2.3(±0.1)·10^(12) erg mole^(−1)/RT] where R is the gas constant and T is the temperature in K. Phase boundaries and tie lines in a Ni-Fe-Ru-rich system were determined at 1273, 1073 and 873 K. A wide miscibility gap is present at each temperature, separating a close-packed hexagonal ϵRu-Fe phase from a face-centered cubic γNi-Fe phase, The partitioning behavior of Pt and Ir between phases in a Ni-Fe-Ru-rich system...
The Hermitian two matrix model with an even quartic potential - Duits, Maurice; Kuijlaars, Arno B. J.; Mo, Man Yue
We consider the two matrix model with an even quartic potential W(y) = y^4/4 + αy^2/2 and an even polynomial potential V(x). The main result of the paper is the formulation of a vector equilibrium problem for the limiting mean density for the eigenvalues of one of the matrices M_1. The vector equilibrium problem is defined for three measures, with external fields on the first and third measures and an upper constraint on the second measure. The proof is based on a steepest descent analysis of a 4 x 4 matrix valued Riemann-Hilbert problem that characterizes the correlation kernel for...
More than a memoir - Leonard, Nelson J.
This autobiography was written originally as a test of memory, as a means of diminishing piles of stored papers and file folders, and in an effort to record events as they actually happened. It had been my experience as a child, hearing oral histories presented by adult family members, that there was great variance in their perceptions. Perhaps I could set down the "facts" of a life and leave interpretations up to any readers.
Each of the chapters was distributed to my four children, Kenneth, Marcia, James and David. Inasmuch as they read the sporadic mailings, I incorporated their corrections and...
Evolving Brains - Allman, John Morgan
Given that all organisms share a common ancestry, why is it that they differ so greatly in their capacities to sense, remember, and respond to the world about them? How did we gain our ability to think and to feel? How do we differ from other organisms in these capacities? Our brain endows us with the faculties and the drive to ask these fundamental questions. The answers depend crucially on understanding how brains have evolved. This inquiry into brain evolution is interdisciplinary and multifaceted, based on converging evidence obtained from the study of the genetic regulation of development, the geological...