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Thirteen archeological specimens were analyzed spectrographically, and within defined limits they were determined to be native copper. Twelve of the specimens show close elemental homogeneity and are believed to be of Lake Superior ore; the origin of the other specimen is devious....

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...

X-ray diffraction crystal-structure analysis of omphacite from eclogite, Tiburon Peninsula, Marin County, California, shows that this clinopyroxene has P2 symmetry with a nearly ordered distribution of the multiple cation content defined by its approximate formula: (Na0.5Ca0.5) (Mg0.4Fe2+0.1Al0.4Fe3+0.1)Si2O6. Na+ and Ca2+ tend to assume alternate locations in the structure, and...

Sediments from a unique high-altitude lake on Hawaii indicate ash falls and other airborne and waterborne materials for a period estimated to extend into the Pleistocene....

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...

The linear relation observed in a log Ca++ versus log Br- plot for subsurface Cl- waters is attributed to ultrafiltration by shale of sea water and fresh water that have passed through sedimentary rocks since their formation. Reactions between these solutions and sedimentary minerals, particularly dolomitization, must have contributed additional Ca++ to solution....

An electrochemical device was used to measure the fugacity of oxygen (fO2) in holes drilled through the crust of Makaopuhi lava lake, Kilauea Volcano, Hawaii. Results obtained within 6 months of the lake formation show that log fO2 normally varies linearly with the reciprocal of the absolute temperature, and that chemical changes...

The isotopic compositions of lead and the concentrations of lead, uranium, and thorium in samples of oceanic tholeiite and alkali suites are determined, and the genetic relations of the oceanic basalts are discussed. Lead of the oceanic tholeiites has a varying lead-206 : lead-204 ratio between 17.8 and 18.8, while...

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....

Profiles of repetitive seismic reflections reveal that the Bering continental slope, outer shelf, and rise overlay an acoustically reflective "basement" which extends at least 750 kilometers parallel to the trend of the slope. This acoustic basement is usually covered by several hundred meters of stratified sediments at the top and...

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...