Publications
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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 coverage of t
Authors
A. Meloni, L. Cafarella, P. De Michelis, R. Tozzi
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 measurements
Authors
Jeffrey J. Love
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 Pearson (1901)
Authors
Jeffrey J. Love
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, that was
Authors
Jeffrey J. Love, J.B. Townshend
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 specifically to qua
Authors
Jeffrey J. Love, K.J. Remick
Study of a prehistoric landslide using seismic reflection methods integrated with geological data in the Wasatch Mountains, Utah, USA
An integration of geological and geophysical techniques characterizes the internal and basal structure of a landslide along the western margin of the Wasatch Mountains in northern Utah, USA. The study area is within a region of planned and continuing residential development. The Little Valley Landslide is a prehistoric landslide as old as 13??ka B.P. Drilling and trenching at the site indicate tha
Authors
B.E. Tingey, J.H. McBride, T.J. Thompson, W. J. Stephenson, J.V. South, M. Bushman
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 modelling,
Authors
Y. Bozorgnia, K.W. Campbell, N. Luco, J.P. Moehle, F. Naeim, P. Somerville, T.Y. Yang
Hazard assessment of the Tidal Inlet landslide and potential subsequent tsunami, Glacier Bay National Park, Alaska
An unstable rock slump, estimated at 5 to 10 × 106 m3, lies perched above the northern shore of Tidal Inlet in Glacier Bay National Park, Alaska. This landslide mass has the potential to rapidly move into Tidal Inlet and generate large, long-period-impulse tsunami waves. Field and photographic examination revealed that the landslide moved between 1892 and 1919 after the retreat of the Little Ice A
Authors
G. F. Wieczorek, E.L. Geist, R.J. Motyka, M. Jakob
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 1308 historic
Authors
W.H. Schulz
Risk-targeted versus current seismic design maps for the conterminous United States
The probabilistic portions of the seismic design maps in the NEHRP Provisions (FEMA, 2003/2000/1997), and in the International Building Code (ICC, 2006/2003/2000) and ASCE Standard 7-05 (ASCE, 2005a), provide ground motion values from the USGS that have a 2% probability of being exceeded in 50 years. Under the assumption that the capacity against collapse of structures designed for these "uniform
Authors
Nicolas Luco, Bruce R. Ellingwood, Ronald O. Hamburger, John D. Hooper, Jeffrey K. Kimball, Charles A. Kircher