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During the last four years our knowledge of the geology of the terrestrial planets has advanced rapidly. The advances are particularly noticeable for Venus and Mars. Improved understanding of Venus has come largely from the Pioneer Venus mission. The period was also one of almost continuous data gathering for Mars...

Holocene-Pliocene sequence sampled in northern Baja California. Geochemical data supported by petrographic, X-ray, and SEM observations of mineralogical transformations, fission-track radiography, and uranium decay series measurements. Results indicate that metal content of the studied samples is inherited from constituent detrital minerals and that reddening of whole-rock samples does not promote...

Monthly streamflow records at a site are sometimes extended by exploiting interstation correlation of streamflow, often through simple linear regression with a base station having a long-term record. An approach is presented which selects a base station from among several in a region for filling in missing data. It differs...

Electrophoretic analysis was performed on eight protein systems (lactate dehydrogenase, liver esterases, superoxide dismutase, haemoglobin, isocitrate dehydrogenase, glucose-6-phosphate dehydrogenase, 6-phosphogIuconate dehydrogenase, transferrin) in Ctenopharyngodon idella, Hypophthalmichthys nobilis, and their F1 triploid hybrid. The data demonstrated codominant Mendelian inheritance at individual loci for each protein system. Transferrin and superoxide dismutase were the only...

Growth and survival were compared for first‐feeding fry of Atlantic salmon (Salmo salar) fed a closed‐formula commercial preparation, BioDiet, or U.S. Fish and Wildlife Service high nutrient density diets 398 or 406 for 14 weeks. Growth of fry fed BioDiet for 2, 3, 4, or 6 weeks from first feeding...

The development and application of digital cartographic data bases are significant and important activities in the Federal Government. Increasingly, digital spatial data are being used for computer-based analyses in support of management decisions on land, forests, minerals, and energy....

Distribution and isotopic composition (δ13C) of low molecular weight hydrocarbon gases were studied in Big Soda Lake (depth = 64 m), an alkaline, meromictic lake with permanently anoxic bottom waters. Methane increased with depth in the anoxic mixolimnion (depth = 20–35 m), reached uniform concentrations (55 μM/l) in the monimolimnion...

Plutonic rocks of Jurassic age exposed on the eastern, or Pacific, side of the Alaska–Aleutian Range batholith represent the roots of a magmatic arc generally considered to have been generated in response to northwest-directed subduction. These rocks form a compositionally continuous calc-alkaline suite...

[No abstract available]...

Big Soda Lake is an alkaline, saline lake with a permanent chemocline at 34.5 m and a mixolimnion that undergoes seasonal changes in temperature structure. During the period of thermal stratification, from summer through fall, the epilimnion has low concentrations of dissolved inorganic nutrients (N, Si) and CH4, and low...

Domes offer unique opportunities to measure or infer the characteristics of magmas that, at domes and elsewhere, control explosive activity. A review of explosive activity associated with historical dome growth shows that: 1. (1) explosive activity has occurred in close association with nearly all historical dome growth; 2. (2) whole-rock...

Old Crow tephra is the first extensive Pleistocene tephra unit to be documented in the northwestern part of North America. It has a calc-alkaline dacitic composition with abundant pyroxene, plagioclase, and FeTi oxides, and minor hornblende, biotite, apatite, and zircon. Thin, clear, bubble-wall fragments are the dominant type of glass...

Heat capacities (5-380 K) have been measured by adiabatic calorimetry for five highly disordered alkali feldspars (Ab99Or1, Ab85Or15, Ab55Or45, Ab25Or75 and Ab1Or99). The thermodynamic and mineralogical implications of the results are discussed. The new data are also combined with recent data for plagioclases in order to derive a revised expression...

A study of the effects of macroscopic fractures on P and S wave velocities has been conducted in four wells drilled in granitic rock to depths between 0.6 and 1.2 km. The effect of macroscopic fractures is to decrease both Vp and Vs and increase Vp/Vs. In wells with a relatively low density of macroscopic fractures, the in situ...

Thermal fluid discharges at Lassen are dominated by high-altitude fumaroles and acid-sulfate hot springs in the Park, and lower altitude, neutral, high-chloride hot springs in Mill Valley 7-10 km to the south. The interrelations of these fluids have been studied by noble and reactive gas analyses. Atmospheric noble gas (ANG)...

Experiments were carried out in the laboratory to test a theory of transient flow of pure steam in a uniform porous medium. This theory is used in modeling pressure transient behavior in vapor dominated geothermal systems. Transient, superheated steam flow experiments were run by bringing a cylinder of porous material...

No abstract available....