Cretaceous-Tertiary events in Southeast Asia: Discussion
Thomas W.C. Hilde, Celeste G. Engel
1969, Geological Society of America Bulletin (80) 1887-1887
No abstract available....
A system for planning and scheduling water resources studies and construction projects
E. F. LeRoux, D. G. Jorgenson
1969, Groundwater (7) 16-18
A simplification of the two most commonly used methods of network planning and scheduling is ideally suited to the planning and evaluation of both water resources studies and construction projects. The project planning diagrams illustrate the system for scheduling of project activities and the relation of...
An application of surface geophysical techniques to the study of watershed hydrology
Ronald R. Shields, William E. Sopper
1969, Journal of the American Water Resources Association (JAWRA) (5) 37-49
The applicability of geophysical methods to experimental watershed research is demonstrated by a study of a 106-acre forested watershed in central Pennsylvania. Data from a shallow seismic refraction study and an electrical resistivity study of the watershed were used to determine the depth of soils, their volumes, depth to bedrock,...
Chemical composition of the hydrothermal fluids responsible for the lead-zinc deposits at Providencia, Zacatecas, Mexico
Robert O. Rye, Joseph Haffty
1969, Economic Geology (64) 629-643
The chemical composition of 22 samples of primary fluid inclusions in quartz, calcite, and sphalerite from Providencia, Mexico, has been determined. Samples were prepared, crushed, and leached as described by Roedder et al. (1963). Cation analyses of leachates were made by atomic absorption spectroscopy, and the anions were analyzed by...
The ground-water situation in Ohio
Stanley E. Norris
1969, Groundwater (7) 25-33
Present ground-water use in Ohio, approximately 650mgd (million gallons per day) amounts to about 5 percent of the water that enters the ground-water reservoirs. The largest ground-water supplies are developed where natural concentrations of water occur, chiefly in the watercourse aquifers, which consist of sand and gravel of glacial origin...
Aeromagnetic investigation of crustal structure for a strip across the western United States
Isidore Zietz, Paul C. Bateman, James E. Case, M. D. Crittenden Jr., Andrew Griscom, Elizabeth R. King, R. J. Roberts, George R. Lorentzen
1969, Geological Society of America Bulletin (80) 1703-1714
This report represents part of a larger study undertaken to interpret the gross features of the earth's crust by aeromagnetic methods. The larger survey covers a 100-mile-wide strip along a great circle arc from Washington, D.C., to San Francisco, California. The area considered extends from about 200 miles east of...
Glacial age marsh, Lafayette Park, Washington, D.C.
A.S. Knox
1969, Science (165) 795-797
Organic sediments beneath historic Lafayette Park mark the site of a freshwater marsh which bordered the Potomac River when it was 15 meters above its present level. Plant microfossils and ice-rafted boulders indicate a climate much colder than now. The carbon-14 age of more than 45,000 years and palynological studies...
Tertiary climatic change in the marginal northeastern Pacific Ocean
W.O. Addicott
1969, Science (165) 583-586
Analysis of distributional patterns of shallow-water molluscan faunas of the middle latitudes of the marginal northeastern Pacific Ocean discloses a sharp reversal during the Miocene of the progressive climatic deterioration. A low point in the Tertiary cooling trend during the Oligocene was followed by climatic warming that culminated during the...
Paleozoic tectonic history of the Arctic basin north of Alaska
M. Churkin Jr.
1969, Science (165) 549-555
No abstract available. ...
Cretaceous, Tertiary, and early Pleistocene rocks from the continental margin in the Bering Sea
David M. Hopkins, David W. Scholl, Warren O. Addicott, Richard L. Pierce, Patsy Beckstead Smith, Jack A. Wolfe, David Gershanovich, Boris Kotenev, Kenneth E. Lohman, Jere H. Lipps, John D. Obradovich
1969, Geological Society of America Bulletin (80) 1471-1480
Rocks dredged from the continental margin in eastern Bering Sea in and near the Pribilof Canyon indicate that the acoustic basement represents the upper surface of thoroughly lithified turbidite beds of graywacke and siltstone of Late Cretaceous age. The stratified sequence covering the acoustic basement is gently deformed and includes...
Application of deep electrical soundings for groundwater exploration in Hawaii
Adel A. R. Zohdy, Dallas B. Jackson
1969, Geophysics (34) 584-600
Forty-five resistivity soundings, using Schlumberger and equatorial dipole electrode configurations, were made on the islands of Oahu and Hawaii to determine the applicability of direct current resistivity methods for locating freshwater aquifers in the State of Hawaii. The soundings were made on the northwestern part of the island of Oahu...
Geology and geochemistry of the Cortez gold deposit, Nevada
John D. Wells, Lee R. Stoiser, James E. Elliott
1969, Economic Geology (64) 526-537
No abstract available....
Peridotite-gabbro complexes as keys to petrology of mid-oceanic ridges
T. P. Thayer
1969, Geological Society of America Bulletin (80) 1515-1522
Two suites of olivine-rich ultramafic and feldspathic rocks appear to be present in the Mid-Atlantic Ridge: one which seems to have alkalic affinities, and one similar to the chromitite- bearing alpine peridotite-gabbro complexes. The similarities of rocks in the two environments—continental and oceanic—imply that much about the petrology of mid-oceanic...
Primary protodolomite in echinoid skeletons
Johannes H. Schroeder, Edward J. Dwornik, J. J. Papike
1969, Geological Society of America Bulletin (80) 1613-1616
Protodolomite has been identified in the teeth of Recent echinoids by means of electron microprobe and X-ray diffraction analyses. The analyses demonstrate a high degree of heterogeneity with respect to magnesium carbonate content in these skeletal parts; the entire spectrum of compositions between magnesium calcite...
The fossil record of shell boring by snails
Norman F. Sohl
1969, American Zoologist (9) 725-734
The predatory boring habit common to many recent snails probably arose first in the Polinicinae (Naticacea) during Upper Cretaceous (Cenomanian) times (100 million years B.P.) . In the fossil record the frequency of bored shells increases greatly in rocks of latest Cretaceous age and becomes more widespread during early...
A geophysical study of North Park and the surrounding ranges, Colorado
John C. Behrendt, Peter Popenoe, Robert E. Mattick
1969, Geological Society of America Bulletin (80) 1523-1537
A geophysical study in the North Park basin and surrounding mountains, Colorado illustrates the structural relationship of various sedimentary, metamorphic, and igneous rock units. Bouguer anomalies from 1330 gravity stations range from −210 mgal over Precambrian metamorphic rocks in the mountains to −260 mgal in the Walden syncline and —280...
Temporal variation of alkaline earth element/chlorinity ratios in the sargasso sea
G.K. Billings, O.P. Bricker, F.T. MacKenzie, A.L. Brooks
1969, Earth and Planetary Science Letters (6) 231-236
An open ocean hydrographic station located 14 miles SE of the Bermuda Islands was sampled at two week intervals through a vertical profile of 2600 meters and over the period June 1966 to March 1967. 428 samples were analyzed for Ca, Mg, Sr...
Inflation of Kilauea Volcano prior to its 1967-1968 eruption: Vertical and horizontal deformation give clues regarding the structure of an active Hawaiian volcano
Richard S. Fiske, Willie Tomoni Kinoshita
1969, Science (165) 341-349
No abstract available....
Fault-plane Solution of the Koyna (India) Earthquake
W.H.K. Lee, C.B. Raleigh
1969, Nature (223) 172-173
THE peninsular shield of India has long been regarded as a stable region. The area had not been subject to orogenic deformation since the Pre-Cambrian, although a vast area (5 × 105 square km) was flooded by basalts during Late Cretaceous to the Eocene—the Deccan Trap. Several...
Distribution of scandium between coexisting biotite and hornblende in igneous rocks
Robert I. Tilling, L. Paul Greenland, D. Gottfried
1969, GSA Bulletin (80) 651-668
Scandium analyses of more than 90 pairs of coexisting biotite and hornblende from igneous rocks of various provinces (including Southern California, Boulder, Sierra Nevada, Boulder Creek batholiths and the Jemez Mountains volcanic rocks) indicate that the distribution ratio (Kd = Schornblende/Scbiotite) for most samples closely approached that of an equilibrium distribution....
Alkalic and tholeiitic basaltic volcanism related to the Rio Grande depression, southern Colorado and northern New Mexico
Peter W. Lipman
1969, Geological Society of America Bulletin (80) 1343-1353
Upper Cenozoic basaltic rocks in and near the northern Rio Grande depression, a major intracontinental tension-rift structure, vary systematically in petrology and chemistry with distance from the depression. Basalts and basaltic andesites of alkalic affinities, commonly showing evidence of crustal contamination, were erupted east and west of the depression concurrently...
Confidence limits for the precision parameter κ
Allan Cox
1969, Geophysical Journal International (17) 545-549
Confidence limits are calculated for the precision parameter κ used in the analysis of palaeomagnetic data and for the angular standard deviation σ. A set of tables for 95 per cent and 99 per cent confidence limits is presented....
Principal stress directions from plastic flow in crystals
Neville L. Carter, C. Barry Raleigh
1969, Geological Society of America Bulletin (80) 1231-1264
Methods for determining orientations of principal stress axes in deformed rocks involve dynamic analysis of twin-gliding and of extinction bands produced by inhomogeneous translation gliding in crystals. The methods, beginning with Turner's (1953) technique for dynamic analysis of calcite twins, have been developed using as...
Carbon isotopes in pelites of the Precambrian Uncompahgre Formation, Needle Mountains, Colorado
Fred Barker, Irving Friedman
1969, Geological Society of America Bulletin (80) 1403-1407
Carbon isotopic ratios and weight percentages of carbon were measured in 15 samples of slate, phyllite, and schist of the approximately 1500- to 1600-m.y.-old Uncompahgre Formation of the Needle Mountains, southwestern Colorado. Rocks with less than 1 percent total carbon, all of which is reduced, have δC13 values of −23 to...
Errors in using modern stream-load data to estimate natural rates of denudation
Robert H. Meade
1969, Geological Society of America Bulletin (80) 1265-1274
The practice of calculating natural rates of denudation from routinely collected data on the loads of suspended and dissolved matter in modern rivers is subject to several significant errors. The sources of these errors are demonstrated by examples from the Atlantic drainage of the United States, where their total effect...
