Publications
Geomagnetism publications.
Filter Total Items: 414
Aeromagnetic survey over U.S. to advance geomagnetic research
A proposed high‐altitude survey of the United States offers an exciting and cost effective opportunity to collect magnetic‐anomaly data. Lockheed Martin Missile and Space Company is considering funding a reimbursable ER‐2 aircraft (Figure 1) mission to collect synthetic aperture radar (SAR) imagery at an altitude of about 21 km over the conterminous United States and Alaska. The collection of tota
Authors
T. G. Hildenbrand, R. J. Blakely, W. J. Hinze, Gordon R. Keller, R.A. Langel, M. Nabighian, W. Roest
Aeromagnetic survey over US to advance geomagnetic research
A proposed high-altitude survey of the United States offers an exciting and cost effective opportunity to collect magnetic-anomaly data. Lockheed Martin Missile and Space Company is considering funding a reimbursable ER-2 aircraft (Figure 1) mission to collect synthetic aperture radar (SAR) imagery at an altitude of about 21 km over the conterminous United States and Alaska. The collection of tota
Authors
T. G. Hildenbrand, R. J. Blakely, W. J. Hinze, Gordon R. Keller, R.A. Langel, M. Nabighian, W. Roest
Geomagnetic storms, the Dst ring-current myth and lognormal distributions
The definition of geomagnetic storms dates back to the turn of the century when researchers recognized the unique shape of the H-component field change upon averaging storms recorded at low latitude observatories. A generally accepted modeling of the storm field sources as a magnetospheric ring current was settled about 30 years ago at the start of space exploration and the discovery of the Van Al
Authors
W.H. Campbell
Preliminary geomagnetic paleointensities from Long Valley Caldera, California
Paleointensities are being determined in order to characterize geomagnetic intensity variations during Quaternary time. Because the geomagnetic field acts as a shield against cosmic radiation, its intensity directly affects the production rate of radiocarbon (^C) in the upper atmosphere. Coe and others (1978) showed that the variation in dipole moment during Holocene time is nearly proportional to
Authors
Edward A. Mankinen
Broad trends in geomagnetic paleointensity on Hawaii during Holocene time
Paleointensity determinations have been obtained from 22 basaltic lava flows on the island of Hawaii using the Thelliers' method. Radiocarbon dating indicates that these flows erupted at intervals ranging from about 200 to 1000 years, and results of the experiments provide an estimate of broad trends in geomagnetic paleointensity during Holocene time in the vicinity of Hawaii. Most of the samples
Authors
Edward A. Mankinen, Duane E. Champion
Evaluation of models proposed for the 1991 revision of the International Geomagnetic Reference Field
The 1991 revision of the International Geomagnetic Reference Field (IGRF) comprises a definitive main-field model for 1985.0, amain-field model for 1990.0, and a forecast secular-variation model for the period 1990-1995. The five 1985.0 main-field models and five 1990.0 main-field models that were proposed have been evaluated by comparing them with one another, with magnetic observatory data, and
Authors
N. W. Peddie
Quiet geomagnetic field representation for all days and latitudes
This paper describes a technique for obtaining the quiet-time geomagnetic field variation expected for all days of the year and distribution of latitudes from a limited set of selected quiet days within a year at a discrete set of locations. We used a data set of observatories operated by Indian and USSR scientists in 1976 and 1977 near 75°E longitude as illustration. Our method relies upon spatia
Authors
W.H. Campbell, E.R. Schiffmacher, B.R. Arora
Analysis of geomagnetic secular variation during 1980-1985 and 1985- 1990, and geomagnetic models proposed for the 1991 revision of the International Geomagnetic Reference Field
The secular variation of the main geomagnetic field during the periods 1980-1985 and 1985-1990 was analyzed in terms of spherical harmonics up to the eighth degree and order. Data from worldwide magnetic observatories and the Navy's Project MAGNET aerial surveys were used. The resulting pair of secular-variation models was used to update the Definitive Geomagnetic Reference Field (DGRF) model for
Authors
N. W. Peddie