Publications
Filter Total Items: 2378
Earthquake hazard in the heart of the homeland Earthquake hazard in the heart of the homeland
Evidence that earthquakes threaten the Mississippi, Ohio, and Wabash River valleys of the Central United States abounds. In fact, several of the largest historical earthquakes to strike the continental United States occurred in the winter of 1811-1812 along the New Madrid seismic zone, which stretches from just west of Memphis, Tenn., into southern Illinois. Several times in the past...
Authors
Joan Gomberg, Eugene Schweig
The contribution of geomagnetic observatories and magnetic models to the study of secular variation and jerks in Antarctica The contribution of geomagnetic observatories and magnetic models to the study of secular variation and jerks in Antarctica
Some of the most interesting features of the geomagnetic field and its time variations are displayed in polar areas. Observatory monthly means usually provide an excellent opportunity to study the temporal changes of the magnetic field at a given location. Unfortunately, on the Antarctic continent the distribution of the permanent ground- based observatories does not permit a uniform...
Authors
A. Meloni, L. Cafarella, P. De Michelis, R. Tozzi
Statistical methods for paleovector analysis Statistical methods for paleovector analysis
Our concern is with the statistical description of paleomagnetic vectors and the estimation of their mean and variance. These vectors may come from a number of different rock units or archeological samples, representing a range of acquisition times, and be useful for studies of the mean paleomagnetic field and paleosecular variation; alternatively, the vectors may come from individual...
Authors
Jeffrey J. Love
Principal component analysis in paleomagnetism Principal component analysis in paleomagnetism
When studying the mean and variance of paleomagnetic data it is a common practice to employ principal component analysis (Jolliffe, 2002). The theory of this method is related to the mathematics quantifying the moment of inertia of a set of particles of mass about some reference point of interest. For the purposes of data analysis, principal component analysis was first promoted by...
Authors
Jeffrey J. Love
Observatories, program in USA Observatories, program in USA
The Geomagnetism Program of the US Geological Survey has, for over a century now, monitored the Earth's magnetic field through a network of magnetic observatories and conducted scientific analysis on the data collected. The program traces its origins to the Reorganization Act of 1843, in which Congress authorized the creation of a coastal survey agency, as part of the Treasury Department...
Authors
Jeffrey J. Love, J.B. Townshend
Magnetic indices Magnetic indices
Magnetic indices are simple measures of magnetic activity that occurs, typically, over periods of time of less than a few hours and which is recorded by magnetometers at ground‐based observatories (Mayaud, 1980; Rangarajan, 1989; McPherron, 1995). The variations that indices measure have their origin in the Earth's ionosphere and magnetosphere. Some indices having been designed...
Authors
Jeffrey J. Love, K.J. Remick
Regression models for estimating coseismic landslide displacement Regression models for estimating coseismic landslide displacement
Newmark's sliding-block model is widely used to estimate coseismic slope performance. Early efforts to develop simple regression models to estimate Newmark displacement were based on analysis of the small number of strong-motion records then available. The current availability of a much larger set of strong-motion records dictates that these regression equations be updated. Regression...
Authors
R.W. Jibson
Ground motion issues for seismic analysis of tall buildings: A status report Ground motion issues for seismic analysis of tall buildings: A status report
The Pacific Earthquake Engineering Research Center (PEER) is coordinating a major multidisciplinary programme, the Tall Buildings Initiative (TBI), to address critical technical issues related to the design and analysis of new tall buildings located in coastal California. The authors of this paper, listed alphabetically, are involved in various research studies related to ground motion...
Authors
Y. Bozorgnia, K.W. Campbell, N. Luco, J.P. Moehle, F. Naeim, P. Somerville, T.Y. Yang
Surface-source downhole seismic analysis in R Surface-source downhole seismic analysis in R
This report discusses a method for interpreting a layered slowness or velocity model from surface-source downhole seismic data originally presented by Boore (2003). I have implemented this method in the statistical computing language R (R Development Core Team, 2007), so that it is freely and easily available to researchers and practitioners that may find it useful. I originally applied...
Authors
Eric M. Thompson
Landslide susceptibility revealed by LIDAR imagery and historical records, Seattle, Washington Landslide susceptibility revealed by LIDAR imagery and historical records, Seattle, Washington
Light detection and ranging (LIDAR) data were used to visually map landslides, headscarps, and denuded slopes in Seattle, Washington. Four times more landslides were mapped than by previous efforts that used aerial photographs. The mapped landforms (landslides, headscarps, and denuded slopes) were created by many individual landslides. The spatial distribution of mapped landforms and...
Authors
W.H. Schulz