Publications

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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...

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...

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...

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...

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...

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.

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...

No abstract available.

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...

The 1959 eruption of Kilauea volcano is unique among recent Kilauea summit eruptions (1952 to 1968) in at least two respects: (1) a large collapse of Kilauea summit accompanied the eruption, and (2) the erupted lavas show a complex variation in their bulk chemical composition. Both features suggest that the 1959 eruption was fed from a source different from that which fed other summit...

Review of quantitative data, restricted range in gold content (rarely more than 10 ppb, generally below 5 ppb), mafic rocks have more, so do early crystallizing minerals, no use in exploration, factors other than concentration determine mineralization; examples