Sr, Nd and Pb isotopes in Proterozoic intrusives astride the Grenville Front in Labrador: Implications for crustal contamination and basement mapping
L.D. Ashwal, J. L. Wooden, R.F. Emslie
1986, Geochimica et Cosmochimica Acta (50) 2571-2585
We report Sr, Nd and Pb isotopic compositions of mid-Proterozoic anorthosites and related rocks (1.45-1.65 Ga) and of younger olivine diabase dikes (1.4 Ga) from two complexes on either side of the Grenville Front in Labrador. Anorthositic or diabasic samples from the Mealy Mountains (Grenville Province) and Harp Lake (Nain-Churchill...
Dating the upper Cenozoic sediments in Fisher Valley, southeastern Utah (USA)
Steven M. Colman, Anne F. Choquette, J.M. Rosholt, G. H. Miller, D.J. Huntley
1986, Geological Society of America Bulletin (97) 1422-1431
More than 140 m of upper Cenozoic basin-fill sediments were deposited and then deformed in Fisher Valley between about 2.5 and 0.25 m.y. ago, in response to uplift of the adjacent Onion Creek salt diapir. In addition to these basin-fill sediments, minor amounts of eolian and fluvial sand were deposited...
Improved phase-ellipse method for in-situ geophone calibration
Huaibao P. Liu, L. Peselnick
1986, Geophysical Prospecting (34) 537-544
For amplitude and phase response calibration of moving-coil electromagnetic geophones two parameters are needed, namely, the geophone natural frequency, f0, and the geophone upper resonance frequency fu. The phase-ellipse method is commonly used for the in situ determination of these parameters. For a given signal-to-noise ratio, the precision of the measurement off0 andfu depends...
A coefficient of agreement as a measure of thematic classification accuracy.
G.H. Rosenfield, K. Fitzpatrick-Lins
1986, Photogrammetric Engineering and Remote Sensing (52) 223-227
The classification error matrix typically contains tabulated results of accuracy evaluation for a thematic classification, such as a land-use and land-cover map. Diagonal elements of the matrix represent counts correct. The usual designation of classification accuracy has been total percent correct. Nondiagonal elements of the matrix have usually been neglected....
Palynological evidence for the historic expansion of juniper and desert shrubs in Arizona, U.S.A.
O.K. Davis, R. M. Turner
1986, Review of Palaeobotany and Palynology (49) 177-193
Analysis of the sediment of Pecks Lake, Yavapai County, Arizona, has permitted the first reported palynological evidence for the historic expansion of juniper and desert shrubs in the American Southwest. The palynological evidence is supported by the comparison of modern and historical photographs, which shows the regional expansion of pinyon-juniper...
Middle Devonian to Late Mississippian event stratigraphy of Overthrust belt region, western United States
Charles Sandberg, R.C. Gutschick, J.G. Johnson, F. G. Poole, W.J. Sando
1986, Annales - Societe Geologique de Belgique (109) 205-207
Twenty eustatic and epeirogenic events mainly dated by conodonts are distinguished between the Middle Devonian and the lower Upper Mississippian in Great Basin, in Rocky Mountains and in the Overthrust belt regions....
FASP, an analytic resource appraisal program for petroleum play analysis
R. A. Crovelli, R.H. Balay
1986, Computers & Geosciences (12) 423-475
An analytic probabilistic methodology for resource appraisal of undiscovered oil and gas resources in play analysis is presented in a FORTRAN program termed FASP. This play-analysis methodology is a geostochastic system for petroleum resource appraisal in explored as well as frontier areas. An established geologic model considers both the uncertainty...
ARCTIC SEA ICE EXTENT AND DRIFT, MODELED AS A VISCOUS FLUID.
Chi-Hai Ling, Claire L. Parkinson
1986, Ocean science and engineering (11) 71-98
A dynamic/thermodynamic numerical model of sea ice has been used to calculate the yearly cycle of sea ice thicknesses, concentrations, and velocities in the Arctic Ocean and surrounding seas. The model combines the formulations of two previous models, taking the thermodynamics and momentum equations from the model of Parkinson and...
Fission-track dating of the tectonic development of the San Juan Islands, Washington
S. Y. Johnson, R.A. Zimmerman, C. W. Naeser, J. T. Whetten
1986, Canadian Journal of Earth Sciences (23) 1318-1330
The San Juan Islands of Washington State form a geologically complex province located between the north Cascades, Vancouver Island, and the Olympic Peninsula. We have obtained 53 fission-track dates from the San Juan Islands province that help constrain its late Paleozoic to early Cenozoic tectonic and sedimentary history and its...
Heating, cooling, and uplift during Tertiary time, northern Sangre de Cristo Range, Colorado (USA)
D. A. Lindsay, P.A.M. Andriessen, B. R. Wardlaw
1986, Geological Society of America Bulletin (97) 1133-1143
aleozoic sedimentary rocks in a wide area of the northern Sangre de Cristo Range show effects of heating during Tertiary time. Heating is tentatively interpreted as a response to burial during Laramide folding and thrusting and also to high heat flow during Rio Grande rifting.The regional extent of heating is...
Post-glacial lahars of the Sandy River Basin, Mount Hood, Oregon.
K. A. Cameron, P. Pringle
1986, Northwest Science (60) 225-237
Within the last 10 000 years, three significant lahar-producing periods have occurred at Mount Hood, Oregon. The Timberline eruptive period occurred between 1400 and 1800 years BP. It was by far the most voluminous of the three periods, producing enough clastic debris to bury the glacial topography of the southwest...
Piston core properties and disturbance effects.
H. W. Olsen, T. L. Rice, P. W. Mayne, R.D. Singh
1986, Journal of Geotechnical Engineering (112) 608-625
Laboratory geotechnical data on piston cores for 31 sites on the mid-Atlantic Upper Continental Slope show the near-surface sediments vary from normally consolidated to somewhat overconsolidated clayey silts and silty clays of low to high plasticity. They also exhibit normalized behavior and their index property correlations with the effective-stress friction...
Evolution of the Coast batholith along the Skagway Traverse, Alaska and British Columbia.
F. Barker, Joseph G. Arth, T. W. Stern
1986, American Mineralogist (71) 632-643
Reconnaissance geological mapping of a strip 10-15 km wide across the Coast batholith from Haines to Skagway to the vicinity of Log Cabin was performed. The petrography, major- and minor-element chemistry, geochronology (using the U/Pb method on zircons), and initial ratios of 87Sr/86Sr of a suite of representative samples from...
LONG-TERM EARTHQUAKE PREPAREDNESS IN CHARLESTON, SOUTH CAROLINA.
P. L. Gori, M.R. Greene
1986, Conference Paper
The Charleston, South Carolina, area offers a unique opportunity to conduct studies that give insight into the implementation of policy for long-term earthquake preparedness at the local level. Research by Greene and Gori documented the low state of preparedness in 1981. Recent studies show that earthquake preparedness activities are now...
THERMAL-ENERGY STORAGE IN A DEEP SANDSTONE AQUIFER IN MINNESOTA: FIELD OBSERVATIONS AND THERMAL ENERGY-TRANSPORT MODELING.
R. T. Miller
1986, Conference Paper, Proceedings of the Intersociety Energy Conversion Engineering Conference
A study of the feasibility of storing heated water in a deep sandstone aquifer in Minnesota is described. The aquifer consists of four hydraulic zones that are areally anisotropic and have average hydraulic conductivities that range from 0. 03 to 1. 2 meters per day. A preliminary axially symmetric, nonisothermal,...
Upper mantle structure from teleseismic P wave arrivals in Washington and northern Oregon
C. A. Michaelson, C.S. Weaver
1986, Journal of Geophysical Research Solid Earth (91) 2077-2094
Teleseismic P wave travel time residuals are used to detect lateral velocity heterogeneities in the upper mantle beneath Washington and northern Oregon. The results of an inversion for three-dimensional velocity variations resolves an east dipping high-velocity zone that we interpret as the subducting Juan de Fuca plate. The plate is characterized by...
Resurgence of submersed aquatic macrophytes in the tidal Potomac River, Maryland, Virginia, and the District of Columbia
V. Carter, N. Rybicki
1986, Estuaries (9) 368-375
A 1978–81 survey of submersed aquatic macrophytes in the tidal Potomac River showed that there were virtually no plants in the freshwater tidal river between Chain Bridge and Quantico, Virginia, decades after the disappearance of plants in the late 1930’s. Plant populations were monitored in subsequent years (1983–85) using qualitative...
Influences of quaternary climatic changes on processes of soil development on desert loess deposits of the Cima volcanic field, California
L. D. McFadden, S. G. Wells, J. C. Dohrenwend
1986, Catena (13) 361-389
Soils formed in loess are evidence of both relict and buried landscapes developed on Pliocene-to-latest Pleistocene basalt flows of the Cima volcanic field in the eastern Mojave Desert, California. The characteristics of these soils change systematically and as functions of the age and surface morphology of the lava flow. Four...
Crater Lake, Oregon: A restricted basin with base-of-slope aprons of nonchannelized turbidites
C.H. Nelson, A.W. Meyer, D. Thor, M. Larsen
1986, Geology (14) 238-241
The basin floor of Crater Lake (10-km diameter, 600-m water depth) is covered by up to 75 m of sediment–gravity-flow deposits interbedded with mud. In the upper units (8 m (thick), sand and gravel layers with numerous wedging, strong seismic reflectors characterize the...
Nd-Sr-Pb isotope constraints on the sources of west Maui volcano, Hawaii
E. Hegner, D. Unruh, M. Tatsumoto
1986, Nature (319) 478-480
The origin of the Emperor-Hawaiian volcanic chain is attributed to the northwesterly movement of the Pacific plate over a stationary mantle plume (hotspot)1. There has been considerable controversy as to the nature and number of sources of Hawaiian hotspot volcanism. Thus far, most geochemical models have been based on rock...
Zimbabweite, a new alkali-lead arsenic tantalate from St Anns mine, Karoi district, Zimbabwe
Eugene E. Foord, Joseph E. Taggart, R. V. Gaines, P. L .C. Grubb, R. Kristiansen
1986, Bulletin de Mineralogie (109) 331-336
Zimbabweite (Na,K)2PbAs4(Ta,Nb,Ti)4O18, a new mineral with trivalent arsenic, has been recognized at St Anns mine, southeast of Miami, Karoi district, Zimbabwe, in kaolinized pegmatite and dump material.The mineral is honey yellow-brown in large crystals, which are as much as 1 x 1 x 2 cm, and is clear pale yellow...
Cyclic terpenoids of contemporary resinous plant detritus and of fossil woods, ambers and coals
Bernd R. T. Simoneit, J.O. Grimalt, T.-G. Wang, R.E. Cox, Patrick G. Hatcher, A. Nissenbaum
1986, Organic Geochemistry (10) 877-889
Cyclic terpenoids present in the solvent extractable material of fossil woods, ambers and brown coals have been analyzed. The sample series chosen consisted of wood remains preserved in Holocene to Jurassic sediments and a set of of ambers from the Philippines (copalite), Israel, Canada and Dominican Republic. The brown coals...
BROAD SPECTRUM ANALYSIS FOR TRACE ORGANIC POLLUTANTS IN LARGE VOLUMES OF WATER BY XAD RESINS-COLUMN DESIGN-FACTS AND MYTHS.
J. Gibs, A. Wicklund, I.H. Suffet
1986, Conference Paper, National Meeting - American Chemical Society, Division of Environmental Chemistry
The 'rule of thumb' that large volumes of water can be sampled for trace organic pollutants by XAD resin columns which are designed by small column laboratory studies or pure compounds is examined and shown to be a problem. A theory of multicomponent breakthrough is presented as a frame of...
Late Triassic paleogeography of the southern Cordillera: The problem of a source for voluminous volcanic detritus in the Chinle Formation of the Colorado Plateau region
John H. Stewart, T.H. Anderson, G.B. Hazel, L. T. Silver, J.E. Wright
1986, Geology (14) 567-570
The Upper Triassic Chinle Formation of the Colorado Plateau contains voluminous volcanic detritus evidently derived from a source to the south. Volcanic rocks exposed in southern Arizona and northern Sonora have been assumed to represent this source terrane, but U-Pb isotopic geochronology and...
Downstream effects of Flaming Gorge Reservoir on the Green River, Colorado and Utah
E.D. Andrews
1986, Geological Society of America Bulletin (97) 1012-1023
The Green River is one of the principal tributaries in the Colorado River basin and drains 44,700 m2 in Wyoming, Colorado, and Utah. Since October 1962, flows of the Green River have been regulated by Flaming Gorge Reservoir, which is located 412 river miles upstream from its confluence with the Colorado...
