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Late Pleistocene or Recent lavas from San Quintin, Baja California are basanitoids and alkali basalts. The surface quench temperatures of the lavas average 1 005° C with log fO2">f<span id="MathJax-Span-7"...

Offset Holocene alluvial fans and drainages along the McKinley strand of the Denali fault near the Delta River in the east-central Alaska Range indicate as much as 50 to 60 m of right-lateral displacement during the last 10,000 yrs. Vertical movement of 6 to 10 m during the same time...

Isotopic composition and concentration of lead in whole rock and microcline and concentration of uranium and thorium in whole-rock samples of granite from the Granite Mountains, Wyoming, have been determined. The lead isotopic composition in the whole rocks was found to be highly radiogenic with a range in Pb206/Pb204 of 19.58...

Seismic monitoring around Mount St. Helens, Washington, for 28 days during the summer of 1970 showed that the frequency of local earthquakes was from 3 to 13 per day and very similar to the activity previously observed near Mount Rainier, Washington. The epicenters of the well-recorded earthquakes form a roughly...

The potentiometric surface of the Lloyd aquifer in 1970 locally was as much as 40 feet lower than in 1900. During this period, withdrawal of water from wells was estimated to exceed 300 billion gallons, and the amount of water released from aquifer storage by compressive forces was estimated to be 1.6 billion gallons...

Some unusual characteristics of streamflow occur in regions underlain by carbonate rocks. The streamflow characteristics are related to processes of karstification, these processes being dependent on circulation of subsurface water and solution of the rock to form characteristic topography and underground cavern systems.  Very highly cavernous and permeable unsaturated zones tend to keep the water...

Authigenic zeolites present in the generally tuffaceous Miocene Briones Sandstone and related formations of the central Coast Ranges of California indicate three stages of diagenetic history: (1) Initial alteration of pyroclastic materials to clinoptilolite (and montmorillonite) that is widely distributed in small amounts throughout the region. (2) Subsequent crystallization of heulandite followed by stilbite in fractures...

Two till-like diamictons, 700 feet above present sea level on Admiralty Island, Alaska, are separated by peat near the top of a landslide scarp. The lower diamicton is glaciomarine; the upper diamicton is probably a mudflow. The lower diamicton contains the foraminifer Elphidium clavatum Cushman, a species typical of fiords.  Similar diamicton crops out along...

Hydraulic sand models are useful physical tools in the investigation of the transition zone that occurs between salt and fresh ground water in coastal aquifers. Such models are used to demonstrate the effects of transport mechanisms that influence the dynamic behavior and the shape of the transition zone. The techniques employed in obtaining in-place measurements...

Chemical and physical data are given for five samples of rock-forming apatite from diverse geologic environments in Nevada and Colorado.  Four of these apatites contain rare-earth assemblages in which the cerium group is well represented but the yttrium group predominates.  The fifth apatite contains a highly fractionated assemblage of the lighter (cerium group) rare earths...

Maps with aerial photograph image bases have gained wide popularity. The orthophotomap presents an abundance of ground detail and information that cannot be shown on a line map with standard cartographic symbols. In preparing a map base covering areas of little relief, the imagery is fitted to map control with a conventional rectifier, but for...

Photographs taken on early space missions, in the Gemini-Apollo series, demonstrated the usefulness of the long view for cartography despite acknowledged shortcomings. Later developments, such as ERTS and Skylab, will provide far more data about Earth, but mostly in planimetric form. The third dimension, height, which makes the map representation topographic, is not easy to...

Uranium, thorium, and potassium concentrations were measured in 60 samples collected from an exploratory hole drilled in the Belmont stock about 40 miles north-northeast of Tonopah, Nev.  The results indicate that, at least within 2,000 feet of the surface, the granitic pluton contains radioelement concentrations similar to those in average granodiorites and that local...

The direction of horizontal dilation in areas characterized by tensional tectonics can be determined from a statistical study of en echelon patterns of fracturing observed on aerial photographs. Relative, to a north-south dilation, nearly all directions of zones of dextral (right-lateral) en echelon fractures lie in the northeast quadrant, while those of sinistral (left-lateral) en...

Unchlorinated, tertiary-treated sewage effluent was injected through a well at Bay Park, Long Island, N.Y., into a sand aquifer at a rate of 340 gpm for 10 days. Massive, biologically produced slime deposits formed in the filter pack immediately adjacent to the well screen. Observed head buildup in the recharge well was correlated with the...

The spectrochemical method described herein for determining trace, minor, and major element distribution in native gold is applicable over a wide range of particle sizes and over a very large concentration range. The matrices of samples and standards are very closely matched. The method was tested on 100 nuggets from a gold sample collected in...

In the past, the granitic basement of the Coast Ranges has been thought to be dominantly quartz diorite and low in K-feldspar.  However, a study of outcrops around Monterey Bay, basement well samples, and dredge samples from Monterey Bay shows that the granitic basement averages about 15 to 20 percent K-feldspar.  Therefore, as...

A strongly dendritic submarine canyon system with four major canyons occupies a 30-km indentation in the insular shelf off the south coast of Puerto Rico between Guanica and Ponce.  Each canyon has several headward branches at depths of 100 to 1,100 m.  Each of the five major rivers that reach the coast between Guanica...

Specific-ion electrodes were used to simultaneously determine the activity changes of calcium, hydrogen, sodium, fluoride, and divalent ions when 50 g of a natural, untreated material containing calcium-rich mixed-layer illite-montmorillonite clay, quartz sand, and calcium carbonate was added to 250 ml of natural Canadian River water containing 220 mg/1 Na. Calcium and magnesium were displaced from...

The U.S. Geological Survey recently undertook the investigation of two seemingly unrelated cartographic tasks: (1) the preparation of map copy for digitizing and (2) the production of experimental slope maps. Both tasks, however, require techniques and equipment for changing or manipulating the line weights of existing map symbols and producing suitable reproduction copy. After a...

Trondhjemitic rocks are relatively abundant in the granitic terranes of the western Sierra Nevada and the Klamath Mountains but have not been found in the granitic plutons of the Salinian block, which lies westward, across the San Andreas fault. A ternary plot of modal quartz : K-feldspar : plagioclase from more than 200 granitic...

The orientation of joints in igneous and sedimentary rocks was measured at 21 localities in California, Maine, and New York to investigate the hypothesis that glaciation may open joints in bedrock. A summary of strikes of all joint sets shows the following pattern relative to the direction of glacial advance: two sets, thought to...

No abstract available....

Radioactive cesium in water is concentrated by ion-exchange on finely divided ammonium hexacyanocobalt ferrate (NCFC), and then determined by beta counting. No carrier is added, and the method can be used to determine beta-emitting cesium isotopes at the 10-pCi/l level using a 100-ml sample. Five samples can be prepared for...

Owing to their enormous capacity, ground‐water reservoirs are at least equal in importance to the ground water itself. As regulators of water movement in the hydrological cycle, these reservoirs surpass all lakes combined, natural and manmade. While many aquifers are not well understood, data on many others are adequate for...