Publications
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The morphology and chronology of a landslide near Dillon Dam, Dillon, Colorado
Investigations were made of a landslide at the Dillon Dam site, Dillon, Colo., that included detailed laboratory and field analyses of the mineralogy, chemistry, and physical properties of landslide materials and the bedrock formations from which they were derived. These investigations provide an understanding of the relative importance of various factors contributing to the origin and reactivatio
Authors
E.E. Wahlstrom, T. C. Nichols
Geomagnetic polarity epochs: Nunivak Island, Alaska
New paleomagnetic and potassium-argon dating measurements have been made of basalt flows from Nunivak Island, Alaska, with the following results. (1) The best estimate of the age of the Brunhes/Matuyama polarity epoch boundary is found to be 0.694 m.y. (2) The best estimate of the age of the Gauss/Gilbert boundary is 3.32 m.y. (3) Three normally magnetized flows with ages from 0.93 to 0.88 m.y. ar
Authors
A. Cox, G. B. Dalrymple
Geomagnetic polarity zones for icelandic lavas
Analysis of cores collected from a sequence of lavas in Eastern Iceland has made possible an accurate calculation of the average rate of reversal of the Earth's magnetic field.
Authors
P. Dagley, R.L. Wilson, J. M. Ade-Hall, G.P.L. Walker, S.E. Haggerty, T. Sigurgeirsson, N.D. Watkins, P.J. Smith, J. Edwards, R.L. Grasty
Geomagnetic polarity epochs: new data from Olduvai Gorge, Tanganyika
The lower lava flow of Bed I in Olduvai Gorge, Tanganyika, carries natural remanent magnetization (NRM) having normal polarity. Thermal demagnetization experiments demonstrate the stability of this NRM. Thus the Olduvai geomagnetic polarity event, which was originally named from the upper lava flow in Bed I, is represented in its type locality by two normally magnetized lavas. These lavas have bee
Authors
C. S. Grommé, R. L. Hay
Pliocene geomagnetic polarity epochs
A paleomagnetic and K-Ar dating study of 44 upper Miocene and Pliocene volcanic units from the western United States suggests that the frequency of reversals of the earth's magnetic field during Pliocene time may have been comparable with that of the last 3.6 m.y. Although the data are too limited to permit the formal naming of any new polarity epochs or events, four polarity transitions have been
Authors
G. B. Dalrymple, A. Cox, Richard R. Doell, C. S. Grommé
Geomagnetic polarity epochs: A new polarity event and the age of the Brunhes-Matuyama boundary
Recent paleomagnetic-radiometric data from six rhyolite domes in the Valles Caldera, New Mexico, indicate that the last change in polarity of the earth's magnetic field from reversed to normal (the Brunhes-Matuyama boundary) occurred at about 0.7 million years ago. A previously undiscovered geomagnetic polarity event, herein named the "Jaramillo normal event," occurred about 0.9 million years ago.
Authors
Richard R. Doell, G. B. Dalrymple
Landslides in the vicinity of the Fort Randall Reservoir, South Dakota
No abstract available.
Authors
Christopher Forbes Erskine
Preliminary report on the geologic and geophysical investigations of the Loveland Basin landslide, Clear Creek County, Colorado
No abstract available.
Authors
Charles Sherwood Robinson, Fitzhugh T. Lee, R. D. Carroll
Geomagnetic polarity epochs
[No abstract available]
Authors
A. Cox, Richard R. Doell, G. Brent Dalrymple
Preliminary report on landslides in a part of the Orinda Formation, Contra Costa County, California
No abstract available.
Authors
Dorothy Hill Radbruch, Louise M. Weiler
Geomagnetic polarity epochs and pleistocene geochronometry
[No abstract available]
Authors
A. Cox, Richard R. Doell, G. B. Dalrymple