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Page 5506, results 137626 - 137650

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Not all publications have extents, not all extents are completely accurate
The Nectarian System, a new lunar time-stratigraphic unit
Desiree Stuart-Alexander, Don E. Wilhelm
1975, Journal of Research of the U.S. Geological Survey (3) 53-58
Geologic mapping of the limbs and far side of the Moon has demonstrated the desirability of subdividing the pre-Imbrian rocks. A convenient datum is the Janssen Formation, the ejecta blanket of the Nectaris basin. A new system, herein named the Nectarian System, extends from the base of the Janssen Formation...
K-Ar age of the Similkameen Batholith and Kruger Alkalic Complex, Washington and British Columbia
K. F. Fox Jr., C.D. Rinehart, J. C. Engels
1975, Journal of Research of the U.S. Geological Survey (3) 39-43
Twelve K-Ar age determinations from the Similkameen batholith and the contiguous Kruger Alkalic Complex, including seven newly reported here, range from 69.9 m.y. to 177.2 m.y. Ages of coexisting hornblende and biotite show discordancies ranging from about 72 m.y. to 106 m.y., with hornblende consistently showing the greater analytical age....
Notes on the origin of Colluma Crater, Bolivia
Sam Rosenblum, Reed J. Anderson
1975, Journal of Research of the U.S. Geological Survey (3) 31-38
Colluma Crater, on the semiarid Altiplano (high plain) of western Bolivia, is an oval structure having overall dimensions of 6.7 km by 6.0 km. The structure has two almost concentric cuestaform rims (the inner rim is 3.6 km by 3.1 km) composed of poorly consolidated clastic sediments that dip outward....
Quantitative determination of dawsonite in Green River Shale by powder-sample X-ray diffraction; effect of grinding
E-an Zen, Jane M. Hammarstrom
1975, Journal of Research of the U.S. Geological Survey (3) 21-30
In an effort to evaluate the method of quantitative analysis by X-ray diffraction as a means of determining dawsonite abundances in Green River" oil shale, we performed a series of grinding experiments. Weighed mixtures of dawsonite + quartz and dawsonite + quartz + shale were ground for preset lengths of...
The megaspore genus Henrisporites from the Cretaceous of Massachusetts
Robert H. Tschudy
1975, Journal of Research of the U.S. Geological Survey (3) 15-20
A new megaspore species belonging to the genus Henrisporites was found in Cretaceous (probably Cenomanian) rocks from Massachusetts. Megaspores of Paxillitriletcs dakotaensis (Hall) Hall and Nicolson were found in the same rocks. This paper discusses the occurrence of these two megaspores in North America and describes Henrisporites angustus n. sp....
Ore grade, metal production, and energy
Norman J. Page, S. C. Creasy
1975, Journal of Research of the U.S. Geological Survey (3) 9-13
 Recent resource estimates have been stimulated by national concern over present and pending shortages of energy and mineral resources. Although some believe that the resource base of a commodity is the total amount in the crust, the energy consumption for mining and milling under present technology suggests that grades of...
Changes in the lake trout population of southern Lake Superior in relation to the fishery, the sea lamprey, and stocking, 1950-70
Richard L. Pycha, George R. King
1975, Technical Report 28
Commercial catch and effort statistics for 1929-70, samples of commercial catches in 1959-62, and records of examinations of all lake trout (Salvelinus namaycush) taken commercially in inshore waters of Michigan and Wisconsin in 1962-70 were the basis for descriptions of changes in the population in 1929-70. Abundance fluctuated cyclically and gradually...
Thoracic collapse as affected by the retia thoracica in the dolphin
Clifford A. Hui
1975, Respiration Physiology (25) 63-70
The carcass of a subadult female Delphinus was placed in a hyperbaric chamber and subjected to two simulated dives each equivalent to 69.7 m. In one dive the thorax was in its natural state, and in the other 100 ml of water had been injected into each pleural cavity. Various morphometric...
Productivity and flowering of winter ephemerals in relation to Sonoran Desert shrubs
William L. Halvorson, Duncan T. Patten
1975, American Midland Naturalist (93) 311-319
Ephemeral plant biomass and density on a Sonoran Desert hill near Cave Creek, Arizona, vary relative to shrub canopy type and shrub density. Higher shrub density associated with increased elevation appears to decrease both ephemeral biomass productivity and density, while ephemeral growth is enhanced under a shrub canopy if it...
Thin-section electron microscopy of mature Myxosoma cerebralis (Myxosporidea) spores
P.D. Lunger, B.L. Rhoads, K. Wolf, M.E. Markiw
1975, Journal of Parasitology (61) 476-480
The morphology of purified, mature Myxosoma cerebralis spores was examined by thin-section electron microscopy. Surface architecture corresponded closely to that described in an earlier scanning electron microscopy study of this organism (Lom and Hoffman, 1971). A uniformly thick spore wall is composed of finely granular, electron-lucent material. Intrawall "valvoplasm" at...
Longevity of nonsprouting Ceanothus
Jon E. Keeley
1975, American Midland Naturalist (93) 504-507
Evidence is presented indicating species of Ceanothus in the subgenus Cerastes are generally longer-lived than species in the subgenus Euceanothus. It is proposed that this is due, at least in part, to the unique stem morphology of the former. The stems of these plants have a ribbed appearance which arises...
Search for blood protozoans in the American woodcock
W.B. Krohn, J.R. Hynson
1975, Journal of Wildlife Diseases (11) 107-108
Smears were prepared from heart blood of 55 woodcock collected in central Maine between spring and fall, 1972 and 1973. Peripheral blood taken from the wings of 41 of these birds also was examined. Examination of stained films revealed no infected blood cells. Samples of heart blood from 35 of...