Volcanic ash was recovered from lower Aptian to Albian deposits from DSDP Sites 463, 465, and 466; pelagic clay of the upper Pleistocene to Upper Cretaceous was recovered mainly from Site 464, with minor amounts at Sites 465 and 466 (Figs. 1 and 2). We present X-ray-mineralogy data on pelagic clay and altered volcanic ash recovered from the four Leg 62 sites (Table 1; Fig. 1). In addition, two ...

Clay minerals on Mars have commonly been interpreted as the remnants of pervasive water-rock interaction during the Noachian period (>3.7Ga). This history has been partly inferred by observations of clays in central peaks of impact craters, which often are presumed uplifted from depth. However, combined mineralogical and morphological analyses of individual craters have shown that some central ...

Widespread detection of phyllosilicates (clay minerals) in Noachian (>3.5 Ga) terrains on Mars and their paucity in younger terrains have led to the hypothesis that Noachian conditions were more clement than the colder, drier conditions that have since followed. However, recent clay detections in several Hesperian impact craters suggest that fluvial transport and alteration were possible after ...

B. CARMICHAEL .................................................... Protective Coatings for Mineral and Rock Specimens: DR. ROBERT W. CLARK. A Short Method Obituary: for the Preparation of Animal Tissues for StainSamruel Wesley Stratton: DR. F. C. BROWN. ing: DR. PAUL W. BOWMAN and MARK N. LINCH ...... 439 Recent Deaths .......... 428 Special Articles: Scientific Events: Further Experiments on C...

background: the concentrations of radionuclides like 226ra, 232th and 40k and the dose rate are measured in igneous and metamorphic rock formations in and around chickmagalur. a total of 236 samples from 13 different locations around study area were analyzed. materials and methods: the activity concentrations of the three radioactive elements were determined for mean period of 25000 s using hpg...

The detailed mineralogy of the Bullfrog and Tram Members of the Crater Flat Tuff from drill hole USW-G1 has been examined, primarily to characterize fully the amounts and types of clay minerals in the tuffs and the possible effects clay minerals have on rock properties. Results of bulk sample x-ray diffraction analyses agree closely with previous determinations, although slightly higher clay mi...

a r t i c l e i n f o a b s t r a c t Rock alteration and rind formation in analog environments like Antarctica may provide clues to rock alteration and therefore paleoclimates on Mars. Clastic sedimentary rocks derived from basaltic sources have been studied in situ by martian rovers and are likely abundant on the surface of Mars. However, how such rock types undergo alteration when exposed to...

The characterization of gas migration through low-permeability clay formations has been a focus of R&D programs for radioactive waste disposal, which is also of great importance for shale-gas exploration, and cap-rock behavior of hydrocarbon reservoirs and CO2 sequestration. Laboratory tests on Opalinus clay cores from a shallow borehole in the Mont Terri Underground Research Laboratory (URL) a...