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Preliminary geomagnetic data, College Observatory, Fairbanks, Alaska: March 1990

No abstract available.
Authors
John B. Townshend, Richard V. O'Connell, Carol Ann Varner

Preliminary geomagnetic data, College Observatory, Fairbanks, Alaska: January 1990

No abstract available.
Authors
John B. Townshend, Richard V. O'Connell, Carol Ann Varner

Preliminary geomagnetic data, College Observatory, Fairbanks, Alaska: February 1990

No abstract available.
Authors
John B. Townshend, Richard V. O'Connell, Carol Ann Varner

An evaluation of the accuracy of geomagnetic data obtained from an unattended, automated, quasi-absolute station

A comparison is made of geomagnetic calibration data obtained from a high-sensitivity proton magnetometer enclosed within an orthogonal bias coil system, with data obtained from standard procedures at a mid-latitude U.S. Geological Survey magnetic observatory using a quartz horizontal magnetometer, a Ruska magnetometer, and a total field magnetometer. The orthogonal coil arrangement is used with t
Authors
D.C. Herzog

Rheological analysis of fine-grained natural debris-flow material

Experiments were conducted on large samples of fine-grained material (???2mm) from a natural debris flow using a wide-gap concentric-cylinder viscometer. The rheological behavior of this material is compatible with a Bingham model at shear rates in excess of 5 sec. At lesser shear rates, rheological behavior of the material deviates from the Bingham model, and when sand concentration of the slurry
Authors
Jon J. Major, Thomas C. Pierson

Young volcanic deposits in the Valles Marineris, Mars?

A study of the interior deposits of the central Valles Marineris has led to the discovery of a sequence of deposits that cover the chasma floors and range in thickness from that of thin dust to several kilometers. The emplacement of the deposits was the last major event in the history of the Valles Marineris, following deposition of older layered interior beds, warping, faulting, erosion, and land
Authors
Baerbel K. Lucchitta

Summit Lake landslide and geomorphic history of Summit Lake basin, northwestern Nevada

The Summit Lake landslide, northwestern Nevada, composed of Early Miocene pyroclastic debris, Ashdown Tuff, and basalt and rhyolite of the Black Rock Range, blocked the upper Soldier Creek-Snow Creek drainage and impounded Summit Lake sometimes prior to 7840 yr B.P. The slide covers 8.2 km2 and has geomorphic features characteristic of long run-out landslides, such as lobate form, longitudinal and
Authors
B. Brandon Curry, W.N. Melhorn

Source parameters and effects of bandwidth and local geology on high- frequency ground motions observed for aftershocks of the northeastern Ohio earthquake of 31 January 1986

A 10-station array (GEOS) yielded recordings of exceptional bandwidth (400 sps) and resolution (up to 96 dB) for the aftershocks of the moderate (mb ≈ 4.9) earthquake that occurred on 31 January 1986 near Painesville, Ohio. Nine aftershocks were recorded with seismic moments ranging between 9 × 1016 and 3 × 1019 dyne-cm (Mw: 0.6 to 2.3). The two largest aftershocks (depth 5.3, 5.6 km; oblique righ
Authors
G. Glassmoyer, R. D. Borcherdt

What do we mean by accuracy in geomagnetic measurements?

High accuracy is what distinguishes measurements made at the world's magnetic observatories from other types of geomagnetic measurements. High accuracy in determining the absolute values of the components of the Earth's magnetic field is essential to studying geomagnetic secular variation and processes at the core mantle boundary, as well as some magnetospheric processes. In some applications of g
Authors
A.W. Green