Publications
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Electronic thermal sensor and Data Collection Platform technology: Part 5 in Thermal surveillance of active volcanoes using the Landsat-1 Data Collection System
Five Data Collection Platforms (DCP) were integrated electronically with thermall sensing systems, emplaced and operated in an analog mode at selected thermally significant volcanic and geothermal sites. The DCP's transmitted 3260 messages comprising 26,080 ambient, surface, and near-surface temperature records at an accuracy of ±1.15 °C for 1121 instrument days between November 14, 1972 and April
Authors
Duane M. Preble, Jules D. Friedman, David Frank
Rise of a variable-viscosity fluid in a steadily spreading wedge-shaped conduit with accreting walls
Relatively rigid plates making up the outer 50 to 100 km of the Earth are steadily separating from one another along narrow globe-circling zones of submarine volcanism, the oceanic spreading centers. Continuity requires that the viscous underlying material rise beneath spreading centers and accrete onto the steadily diverging plates. It is likely that during the rise the viscosity changes systemat
Authors
Arthur H. Lachenbruch, Manuel Nathenson
Geologic interpretation of an aeromagnetic map of the west-central Columbia Plateau, Washington and Oregon
A low altitude, total intensity aeromagnetic map of the ?west-central Columbia Plateau, underlain principally by the Yakima Basalt,. shows Positive and negative anomalies that stand out from a moderate intensity .background reflecting .interbedded flows of normal and reversed magnetic polarity. One set of anomalies is related to anticlinal ridges, nother follows the traces of known or inferred fau
Authors
Donald A. Swanson, Thomas L. Wright, Isidore Zietz
Chemical compositions of Kilauea east-rift lava, 1968–1971
The major element chemical compositions of lava from four eruptions on the east rift zone of Kilauea between August 1968 and October 1971 reflect three petrologic processes:Production of chemically distinct batches of magma in the mantle.Separation of olivine, augite, and plagioclase from liquid during flow in the rift-zone conduits.Mixing of different magmas during ascent to the surface.Chemicall
Authors
Thomas L. Wright, Don Swanson, Wendell A. Duffield
Mechanism of Formation of Pillow Lava
Much of the ocean floor is covered by lava of a distinctive character. The lava appears to be made up of closely packed ellipsoidal masses about the size and shape of pillows - hence the term pillow lava. Only within the last few years has the abundance of pillow lava on the ocean floor been fully recognized. Ocean-bottom photographs and dredge samples have shown that the great bulk of new ocean f
Authors
James G. Moore
A deep research drill hole at the summit of an active volcano, Kilauea, Hawaii
Drilling and geophysical logging data for a 1,262 m‐deep bore hole in the area inferred to overlie the magma reservoir of Kilauea Volcano, Hawaii, support earlier interpretations based on surface geophysical surveys that a zone of brackish or saline water lies above the reservoir. Temperatures encountered within the hole are not sufficiently high to warrant commercial interest; the maximum tempera
Authors
Charles J. Zablocki, Robert I. Tilling, D. W. Peterson, Robert L. Christiansen, George V. Keller, John C. Murray
Estimating the “thickness” of the Boulder Batholith, Montana, from heat-flow and heat-productivity data
Estimates of minimum thickness of the Boulder batholith, computed using the linear relation between heat flow and heat productivity and assuming constant heat productivity with depth, are highly nonspecific. They can vary between about 3 and 20 km, depending on values of surface-rock heat productivity and values of assumed contribution of nonbatholith heat sources (such as lower crustal and upper
Authors
Robert I. Tilling
Palaeomagnetism and magnetic–polarity zonation in some Oligocene volcanic rocks of the San Juan Mountains, south–western Colorado
Palaeomagnetic results have been obtained from thirty sites in intrusive and extrusive rocks of Oligocene age from the San Juan Mountains, south-western Colorado. All specimens from each site were subjected to af demagnetization, and the reliability of each site determined. Twenty-three sites gave reliable results. Because five sites from the thick intracaldera part of the La Jara Canyon Member of
Authors
J. F. Diehl, Myrl E. Beck, Peter W. Lipman
Stratigraphic value of silicoflagellates in nontropical regions
Silicoflagellates are important biostratigraphic markers for age determination in nontropical regions because age-diagnostic calcareous microfossils are sparse. Upper Cretaceous and Cenozoic biostratigraphic zonation is proposed, based on silicoflagellates from Deep Sea Drilling Project sites in the subantarctic region.
Authors
David Bukry
Preliminary model for extrusion and rifting at the axis of the Mid-Atlantic Ridge, 36°48′ North
The inner rift valley of the Mid-Atlantic Ridge at 36°48′ N. is 1.5 to 3 km wide and 100 to 400 m deep. It is symmetrical in profile with a discontinuous medial ridge 100 to 240 m high and 800 to 1,300 m wide along its axis. The medial ridge is replaced every 1 to 3 km with a central trough 200 to 600 m wide.The medial ridge is apparently built by eruptions of pillow basalt recurring at intervals
Authors
James G. Moore, H.S. Fleming
Geologic map of the Frank Island quadrangle, Yellowstone National Park, Wyoming
No abstract available.
Authors
H. Richard Blank, Harold J. Prostka, William R. Keefer, Robert L. Christiansen
Chemical variation related to the stratigraphy of the Columbia River basalt
Study of major element chemical analyses of Columbia River basalt leads to a grouping of most of the analyses into 11 chemical types which are distinguished with little overlap on a SiO2-MgO variation diagram. Other diagnostic variation diagrams are total iron (‘FeO’)-MgO, K2O-MgO, and TiO2-MgO.A four-unit informal stratigraphy has been adopted in order to define the relations between chemical com
Authors
Thomas L. Wright, Maurice J. Grolier, Don Swanson