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No abstract available. ...

During a long-continued study of the lacustrine beds of the Eocene Green River Formation, I have tried to interpret past events from observation of present-day processes. After a search of some 40 years, four lakes have been found that are producing a kind of organic ooze judged to be a...

Pesticide residues have become a component of nearly all living organisms. Nearly all California birds and fish collected in a 1963 pesticide survey contained residues. Discovery of DDT and metabolites in Antarctic animals in 1964 pushed the distribution of pesticides to the remotest portions of the globe. Exchange of pesticides...

The Gowganda Formation of Ontario consists of conglomerates, quartzites, and argillites deposited in a glacial environment. The distribution of varved argillites and silty limestones suggests continental and marine facies, respectively. Pebble and ripple-drift orientations, distribution of limestones, striated pavements, distribution of the underlying Bruce Group, and Huronian quartzite paleocurrents support...

Permeability and storage characteristics in the Tertiary limestone system of southern United States have developed progressively but non-uniformly as circulation of water and solution in the limestone have changed during the geologic and hydrologic history.The limestone formations, predominantly of Eocene age and subordinated of Oligocene and Miocene age, are widespread...

Aerial photographs of areas of crystalline rock in the Piedmont and Blue Ridge of western North Carolina reveal numerous large-scale arcuate, circular, and elliptical patterns with diameters from 1000 to more than 4000 feet. They are commonly defined by curving streams, curving ridges, and curving belts of contrasting vegetation. Geologic mapping shows that the circular patterns are not related to primary geologic structures;...

Three major cycles of volcanism during the Miocene and Pliocene formed a layered succession of calc-alkaline eruptive materials in the western San Juan Mountains nearly 1.5 miles thick and having a volume greater than 1,000 cubic miles. Each cycle was characterised by major eruptions followed by subsidence in the vent areas, and the resulting structure was a great volcanic plateau surrounding...

Twenty aeromagnetic profiles over a 100-mile-wide strip along the arc of a great circle passing through Denver, Colorado, and Washington, D. C, reveal large anomalies of major crustal significance. Contoured data disclose several areas of distinct magnetic patterns reflecting basement lithology and structure. The mafic rocks of the Blue Ridge and Piedmont and the Keweenawan mafic belt in...

A study of 23,000 miles of total intensity aeromagnetic profiles in the central Arctic has been made by the U. S. Geological Survey and the U. S. Coast and Geodetic Survey. The profiles were flown at 20,000 feet above sea level and cover approximately 1,350,000 square miles of the Arctic Ocean between the North Pole...

Radiometric ages have been measured on rocks of a crystalline terrane that includes ancient gneisses and migmatites, two granitic batholiths (St. Kevin Granite and granite of Cross Creek), and various minor intrusive rocks. A whole-rock Rb-Sr isochron age on the St. Kevin Granite establishes it as 1390 ± 60 m.y. old. Mineral ages on the St. Kevin and numerous other rocks are either about the same as the St. Kevin whole-rock age...

The geometry of individual major folds from the Glen Cannich area in the Northern Highlands of Scotland is described. The major folds are isoclinal, and their axial planes and fold limbs strike north or northeast and dip steeply; the fold axes plunge steeply toward the south or southeast. If pairs of individual folds are joined along a common axial-plane trace they form basins, domes, or other unusual...

A zone, 1 to 50 feet thick, at the base of the Nonesuch Shale, is relatively rich in copper, chiefly as chalcocite. Pyrite is the characteristic sulfide mineral of the overlying 400 to 600 feet of the formation. The boundary of the cupriferous zone with the pyrite zone regionally transgresses both stratigraphic layering and fades gradations indicative...

Detailed observations were made on the emergence and feeding habits of the acrocerid parasite Ogcodes rufoabdominalis from lycosid spiders. One hundred and twenty field-collected hosts yielded six parasites in May. Eggs, first and third instars, and pupae are described for the first time, as well as mating and oviposition....

Construction of a flexible plastic collar for marking geese is described. The usefulness of the collars, tried on 468 Canada geese (Branta canadensis) at the Seney National Wildlife Refuge from 1963 to 1965, was compared with that of nasal discs attached to 361 Canada geese at Seney in 1961 and...

The habits of the redhead duck (Aythya americana) were studied in the Flathead Valley of western Montana in 1960 and 1961 to determine their habitat preferences in this pothole breeding ground. The 2,600-acre study area, surrounding the Ninepipe Reservoir, contained 686 potholes. Redheads usually were paired by the time they...

The States of Nebraska and Kansas are negotiating a compact for apportionment of the waters of the Big and Little Blue Rivers. So that the negotiating officials could allocate the water equitably, the amount of streamflow depletion caused by ground‐water withdrawals upgradient from the State line needed to be determined. At the request of the Nebraska officials, the U. S. Geological Survey...

No abstract available. ...

The frequency distribution of dissolved‐solids content of ground waters in geologically and climatologically homogeneous terrane units commonly approximates a log‐normal distribution. A graphic logarithmic transformation is de‐scribed which permits rapid calculation of approximate values for the mean, standard deviation, and coefficient of variation. Statistical parameters calculated by this method show good agreement with known physical conditions in the terranes studied and are...

Sir Charles Cotton (1964) has pointed out that in an earlier paper (Carlston, 1963) which related drainage density to hydrology, there was insufficient emphasis on the role of climate in its effect on drainage density. Re-examination of the relation of drainage density to base flow in the 15 basins originally...

Dawsonite NaAl(OH)2C03 is a rare mineral that occurs in relative abundance over hundreds of square miles in the Piceance Creek Basin of northwestern Colorado, as a rock-forming constituent of the oil shales in the green River Formation. In some specimens it makes up 25 percent by weight of the shale....

Analyses of lead isotopes in galena in carbonate rock ore deposits collected from several mineralized districts in the Central and Eastern Interior of the United States support previous studies in establishing that the galena is anomalously radiogenic ("J"type")- This study, using care-fully selected samples to test some géologie relationships, shows region-wide and distrietwide systematic variations in isotope...

The equilibrium diagram for the Fe-Zn-S System has been worked out in détail from 580° to 850° C. Previous work on this System is proven to be seriously in error and températures heretofore estimated from the "sphalerite geothermometer" are without a sound quantitative foundation. Sphalerite solid solutions lie essentially along the FeS-ZnS join. Neither pyrite nor pyrrhotite takes up appréciable amounts of...

No abstract available....

Some immature mourning doves (Zenaidura macroura) are capable of breeding in their first (calendar) year of life. The breeding activities of immatures observed in this study included calling, copulating, and nesting. Development of sexual structures such as cloacal papillae, oviduct openings, and gonads was also regarded as evidence of breeding...

The tidal efficiencies of wells tapping the principal artesian aquifer in Glynn County, Georgia decrease with distance from the influencing tidal body and also decrease with well depth. Although the magnitude of water‐level fluctuation of these wells is largely dependent upon the distance to a large tidal body, the time of a high or a low water level in the wells is...