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New magnetization data for Late Cretaceous glassy welded tuffs, volcanic breccias, and altered basalts from the Elkhorn Mountains volcanic field, together with geologic, mineralogic, and K-Ar data, indicate that (1) the glassy tuffs have unusually strong, uniform remanent magnetizations which are reversely polarized, much of the remanence perhaps residing in submicroscopic single-domain iron oxide particles within...

Man's activities have caused great changes in Lake Michigan in the past 120 years. Although changes in water chemistry and lower biota have been generally modest (except locally), those in native fish stocks have been vast. Exploitation, exotic fish species, and eutrophication and other forms of pollution all have played...

Potential commercial fish production was estimated for U.S. waters of western Lake Erie in 1969 from pounds landed and pounds discarded. Periodic observations of catches in haul seines and trap nets revealed that about 37% of the catch (by weight) in haul seines and 26% of that in trap nets...

The concentrations of uranium, thorium and lead and the lead isotopic composition of Luna 20 soil were determined. The data indicate that the Luna 20 soil is mainly a mixture of highland anorthosites and low-K basalt, but little KREEP basalt. The U-Th-Pb systematics...

Vapor-dominated geothermal systems such as Larderello, Italy, The Geysers, California, and Matsukawa, Japan yield dry or superheated steam when exploited. Models for these systems are examined along with production data and the thermodynamic properties of water, steam and rock. It is concluded that...

In a series of experiments, soil materials were placed in long cylindrical containers, using various packing procedures. Soil columns produced by deposition and simultaneous vibratory compaction were dense and axially uniform, but showed significant radial segregation of particle sizes. Similar results were obtained with deposition and simultaneous impact-type compaction when...

Deuterium and O18 analyses were made on 25 formation-water samples from Miocene (Temblor Formation) and Eocene (McAdams Formation) reservoir rocks at Kettleman North Dome oil field, California, and on three surface water samples from Reef Ridge located about three miles to the west of the field. The δO18 values obtained generally increase with...

The lead content of five whole-rock peridotite inclusions (four lherzolites and one harzburgite) in alkali basalt ranges from 82 to 570 ppb (parts per billion). Approximately 30–60 ppb of this amount can be accounted for by analyzed major silicate minerals (olivine ≤...

The equations describing fluid flow and energy transport in a porous medium can be used to formulate a mathematical model capable of simulating the transient response of a hot-water geothermal reservoir. The resulting equations can be solved accurately and efficiently using a numerical...

Discovery of shock-metamorphosed material establishes the impact origin of Lonar Crater. Coarse breccia with shatter coning and microbreccia with moderately shocked fragments containing maskelynite were found in drill holes through the crater floor. Trenches on the rim yield strongly shocked fragments in which plagioclase has melted and vesiculated, and bombs...

Analyses of rim-to-interior samples of fresh tholeiitic pillow basalts, deuterically altered holocrystalline basalts, and older, weathered tholeiitic basalts from the deep sea indicate that 87Sr/86Sr ratios of the older basalts are raised by low temperature interaction with strontium dissolved in sea water. 87Sr/86Sr correlates...

Instrumentation placed ahead of three model tunnels in the laboratory and ahead of a crosscut driven in a metamorphic rock mass detected stress changes several tunnel diameters ahead of the tunnel face. Stress changes were detected 4 diameters ahead of a model tunnel drilled into nearly elastic acrylic, 2·50 diameters...

Magnetic susceptibility measurements have been made on four glass spherules and fragments from the Luna 20 fines; two at 300°K and two from 300°K to 4°K. From these data the magnetic susceptibility extrapolated to infinite field, the magnetization at low fields and also...

On the basis of petrographic and laboratory and active seismic data for the Fra Mauro breccias, and by comparison with the nature and distribution of the ejecta from the Ries crater, Germany, some tentative conclusions regarding the geologic significance of the Fra Mauro Formation on the moon can be drawn. The Fra Mauro Formation, as...

A large avalanche (21 square kilometers) at the Apollo 17 landing site moved out several kilometers over flat ground beyond its source slope. If not triggered by impacts, then it was as "efficient" as terrestrial avalanches attributed to air-cushion sliding. Evidently lunar avalanches are able to flow despite the lack...

Four evaporite-bearing stratigraphic zones are known in Cretaceous strata of the Cordillera Oriental of Colombia north and east of Bogota. The easternmost and oldest zone is probably of Berriasian to Valanginian age. The next oldest is probably late Barremian to early Aptian in age. The third appears to be Aptian....

The purpose of the infrared (IR) and radar study of the Apollo data is to establish lunar surface conditions in the vicinity of the orbital tracks of the Apollo command modules during the J-series missions. Correlations and comparisons between the Earth-based radar observations, IR observations, and other data will be...

The Descartes highlands are adjacent to the terra plain on which the Apollo 16 lunar module landed (fig. 29-13). A variety of volcanic origins was proposed for the highlands before the mission (refs. 29-4, 29-21, and 29-35 to 29-37), but the returned samples of the area consist almost exclusively of...

The discovery that samples returned from the Cayley Formation at the Apollo 16 landing site consist mainly of nonvolcanic breccias (secs. 6 and 7 of this report) suggests that the hypothesis in which light plains-forming materials may be ejecta from multi-ring basins should be reevaluated (refs 29-15 to 29-17). Improved...

The three cameras—stellar, mapping, and panoramic—together with the laser altimeter, all included in the scientific instrument module (SIM) bay, represent an integrated photogrammatric system with extraordinary potential for extending knowledge of the lunar figure, surface configuration, and geological structure....

The Apollo 15 lunar module (LM) landed at longitude 03°39'20'' E, latitude 26°26'00'' N on the mare surface of Palus Putredinis on the eastern edge of the Imbrium Basin. The site is between the Apennine Mountain front and Hadley Rille. The objectives of the mission, in order of decreasing priority,...

The impact of pesticides on the mortality rates and recruitment rates of nongame birds during the last 25 years was evaluated by studying the population dynamics of 16 species. A mathematical model showing the relations between population parameters that yielded stable populations was developed. The information needed for the model...

Conclusions and Recommendations: Although much of the above information is imprecise and inconclusive, it is evident that the condors foraging habitat is diminishing. Food supply probably is still adequate for free-ranging nonbreeding birds, but could become limited if current land use trends continue. Congregating condors on fewer...

Alaska's Beaufort Sea shelf is characterized by small-scale relief with an average amplitude of 1–2 m and wavelength of 50–100 m. Diving observations confirm that much of the bottom roughness reflects the action of grounded ice. Except for areas in the shadow of...

Fresh water in abundance is contained in large artesian reservoirs in sand and gravel deposits of Tertiary and Quaternary ages in the Pearl River basin, a watershed of 8,760 square miles. Shallow, water-table reservoirs occur in Quarternary deposits (Pleistocene and Holocene) that blanket most of the uplands in .the southern...