Chemical structural studies of natural lignin by dipolar dephasing solid-state 13C nuclear magnetic resonance
Patrick G. Hatcher
1987, Organic Geochemistry (11) 31-39
Two natural lignins, one from a gymnosperm wood the other from angiosperm wood, were examined by conventional solid-state and dipolar dephasing 13C nuclear magnetic resonance (NMR) techniques. The results obtained from both techniques show that the structure of natural lignins is consistent with models of softwood and hardwood lignin. The dipolar...
Coal deposits of the United States
Nelson W. John
1987, International Journal of Coal Geology (8) 355-365
The coal fields of the Unites States can be divided into six major provinces. The Appalachian and Interior Provinces contain dominantly bituminous coal in strata of Pennsylvanian age. The coal seams are relatively thin and are mined both by surface and...
Economics of the coal industry east of the Mississippi, 1973-1982
S.B. Bhagwat
1987, International Journal of Coal Geology (8) 367-373
Government regulations on health, safety and environment have been poppular blamed for the declining productivity in U.S. coal mines since 1970. The stagnation in the coal industry east of the Mississippi is alleged to have been caused by this declining productivity...
Some effects of quiet geomagnetic field changes upon values used for main field modeling
W.H. Campbell
1987, Physics of the Earth and Planetary Interiors (48) 193-199
The effects of three methods of data selection upon the assumed main field levels for geomagnetic observatory records used in main field modeling were investigated for a year of very low solar-terrestrial activity. The first method concerned the differences between the year's average of quiet day field values and the...
Playa-lake basins on the Southern High Plains of Texas and New Mexico: Part I. Hydrologic, geomorphic, and geologic evidence for their development
Waite Osterkamp, W.W. Wood
1987, Geological Society of America Bulletin (99) 215-223
Playa-lake basins of the Southern High Plains, Texas and New Mexico, may originate wherever water periodically can collect in a surficial depression. They expand, however, by hydrologic and geomorphic processes including (1) dissolution of lithologic carbonates by infiltrating water; (2) transport downward of fine-grained clastic and organic material by the...
Hydrogeologic reconnaissance of the Beowawe Geysers geothermal area, Nevada
F. H. Olmsted, F. E. Rush
1987, Geothermics (16) 27-46
The Beowawe Geysers in north-central Nevada are the discharge from a hydrothermal-convection system in a region of high heat flow. The site of thermal-fluid upflow (at about 18 kg/s before drilling and well testing) appears to be related to the intersection...
Origin of lead from green glass of Apollo 15426: A search for primitive lunar lead.
M. Tatsumoto, W. R. Premo, D.M. Unruh
1987, Journal of Geophysical Research Solid Earth (92) 361-371
A major obstacle in lunar U-Pb chronology is the elusiveness of the primary Pb isotopic composition and U/Pb ratio and therefore the Pb evolution for the early history of the moon. In an attempt to seek the primitive lunar Pb isotopic composition, green glass from lunar clod 15426,49 was studied...
Sedimentary processes on the northwestern Iberian continental margin viewed by long-range side-scan sonar and seismic data
James V. Gardner, Robert B. Kidd
1987, Journal of Sedimentary Petrology (57) 397-407
The effects of an eastern boundary current in the North Atlantic have been mapped from about 39° north latitude along the Iberian margin to as far north as 43°30 north latitude at the western margin of Galicia Bank. The geostrophic current has produced sediment drifts that are...
The importance of methane and thiosulfate in the metabolism of the bacterial symbionts of two deep-sea mussels
C.R. Fisher, J.J. Childress, R.S. Oremland, R.R. Bidigare
1987, Marine Biology (96) 59-71
Undescribed hydrocarbon-seep mussels were collected from the Louisiana Slope, Gulf of Mexico, during March 1986, and the ultrastructure of their gills was examined and compared to Bathymodiolus thermophilus, a mussel collected from the deep-sea hydrothermal vents on the Gala??pagos Rift in March 1985. These closely related mytilids both contain abundant...
Use of focal mechanisms to determine stress: A control study.
A.J. Michael
1987, Journal of Geophysical Research Solid Earth (92) 357-368
To allow focal mechanisms to be inverted for the stress field requires a different inversion algorithm than for slickenside data because focal mechanisms do not represent fault slip data unless one can decide which nodal plane is the fault plane. If one can decide which nodal plane is the fault...
Geological setting of U.S. fossil fuels.
C.D. Masters, R. F. Mast
1987, Episodes (10) 308-313
The USA has a special position in terms of fossil fuel development. Not only is it one of the most important nations in terms of resources of oil, gas and coal, but it has also been by far the dominant producer and consumer. In this thorough review of the regional...
Maestrichtian benthic foraminifers from Ocean Point, North Slope, Alaska ( USA).
K. McDougall
1987, Journal of Foraminiferal Research (17) 344-366
Previous studies of fauna and flora from Ocean Point, Alaska, have suggested ages ranging from Campanian to early Eocene and that these assemblages are either highly endemic or commonplace. I demonstrate that the moderately abundant benthic foraminifers constitute early Maestrichtian boreal assemblages common to Canada and northern Europe. Paleoenvironmental analysis...
On predicting changes in the geomagnetic field
L.R. Alldredge
1987, Journal of Geophysical Research Solid Earth (92) 6331-6338
The present method of using constant secular variation rates to forecast magnetic components at a given site or to forecast spherical harmonic coefficients is known to be inaccurate. A new predictive method using trend and trigonometric functions fitted to known past values is used to extrapolate for a few years...
Cretaceous gastropods: contrasts between tethys and the temperate provinces
N. F. Sohl
1987, Journal of Paleontology (61) 1085-1111
During the Cretaceous Period, gastropod faunas show considerable differences in their evolution between the Tethyan Realm (tropical) and the Temperate Realms to the north and south. Like Holocene faunas, prosobranch gastropods constitute the dominant part of Cretaceous marine snail faunas. Entomotaeneata and opisthobranchs usually form all of...
Submersible observations along the southern Juan de Fuca Ridge: 1984 Alvin program.
William R. Normark, Janet L. Morton, Stephanie L. Ross
1987, Journal of Geophysical Research B: Solid Earth (92) 11283-11290
In September 1984, the research submersible Alvin provided direct observations of three major hydrothermal vent areas along the southernmost segment of the Juan de Fuca Ridge (JFR). The submersible operations focused on specific volcanologie, structural, and hydrothermal problems that had been identified during the preceding 4 years of photographic, dredging,...
Rocks of the Thirtynine Mile volcanic field as possible sources of uranium for epigenetic deposits in central Colorado, USA.
K. A. Dickinson
1987, Uranium (4) 43-65
The most likely volcanic source rock for uranium in epigenetic deposits of the Tallahassee Creek uranium district and nearby areas is the Wall Mountain Tuff. The widespread occurrence of the Tuff, its high apparent original uranium content, approx 11 ppm, and its apparent loss of uranium from devitrification and other...
Crystal structure and crystal chemistry of melanovanadite, a natural vanadium bronze.
J.A. Konnert, H. T. Evans Jr.
1987, American Mineralogist (72) 637-644
The crystal structure of melanovanadite from Minas Ragra, Peru, has been determined in space group P1. The triclinic unit cell (non-standard) has a 6.360(2), b 18.090(9), c 6.276(2) A, alpha 110.18(4)o, beta 101.62(3)o, gamma 82.86(4)o. A subcell with b' = b/2 was found by crystal-structure analysis to contain CaV4O10.5H2O. The...
Seismic stratigraphy and facies of continental slope and rise seaward of Baltimore Canyon Trough
John S. Schlee, K. Hinz
1987, American Association of Petroleum Geologists Bulletin (71) 1046-1067
As part of a survey of the United States continental rise seaward of the northern Baltimore Canyon Trough, four major depositional sequences were mapped on a grid of 2,350 km of multichannel seismic reflection profiles. The sequences, which range in age from Jurassic (?) to Quaternary, record a gradual sedimentary...
Diffusivity of a glacial-outwash aquifer by the floodwave- response technique
R.J. Reynolds
1987, Groundwater (25) 290-299
Aquifer diffusivity (transmissivity divided by storage coefficient) was calculated for three sites in a glacial-autwash valley aquifer near Cortland, New York from water-level fluctuations induced by rises in stream stage. The observed response data were analyzed through use of a one-dimensional floodwave-response model to calculate the theoretical head response in...
Source of lead and mineralizing brines for rossie-type Pb-Zn veins in the Frontenac axis area, New York ( USA).
Robert Ayuso, Nora K. Foley, C. Erwin Brown
1987, Economic Geology (82) 489-491
Veins composed mainly of calcite and some galena, sphalerite, fluorite, and other minerals are widespread in the Frontenac axis area of New York and Ontario. In New York, the veins (Fig. 1) occur mainly west and northwest of Gouverneur (Brown, 1983). The veins, mined in the 1800s for lead,...
Use of track detectors for the evaluation of emanating radium content of soil samples.
E. R. Landa, K.K. Nielson
1987, Uranium (4) 97-103
The emanating Ra contents of background and contaminated soils were measured using commercial alpha-track detectors sealed with samples in glass Mason jars for a 179-day period. The observed track densities were linearly correlated with independently measured emanating Ra contents using gamma assays for total Ra and Rn emanation measurements. The...
Dynamics of Mojave Desert shrub assemblages in the Panamint Mountains, California.
Robert Webb, John W. Steiger, Raymond M. Turner
1987, Ecology (68) 478-490
We studied shrub communities in the Panamint Mountains of the Mojave Desert to determine whether vegetational changes after disturbance can be characterized as succession according to modern successional theory. We found, on a variety of disturbed and undisturbed sites, that the rate of change was a function of the type...
Volcanic processes in the Solar System
M. H. Carr
1987, Earthquakes & Volcanoes (USGS) (19) 128-137
This article stresses that terrestrial volcanism represents only part of the range of volcanism in the solar system. Earth processes of volcanicity are dominated by plate tectonics, which does not seem to operate on other planets, except possibly on Venus. Lunar volcanicity is dominated by lava effusion at enormous rates....
36Cl: A tracer in groundwater in the aquia formation of Southern Maryland
C.B. Purdy, A.C. Mignerey, G.R. Helz, D.D. Drummond, P.W. Kubik, D. Elmore, T. Hemmick
1987, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms (29) 372-375
The Aquia Formation (Paleocene) of Southern Maryland, a marine unit consisting predominantly of quartz sands, but containing 20-40% glauconite, represents one of the many productive, heavily pumped aquifers of the Southeastern Coastal Plain. An unusually high 36Cl activity ( ~ 15 ?? modem water) measured in an outcrop sample is...
Geochemistry of metal-rich brines from central Mississippi Salt Dome basin, U.S.A.
Y.K. Kharaka, A.S. Maest, W.W. Carothers, LeRoy M. Law, P. J. Lamothe, T. L. Fries
1987, Applied Geochemistry (2) 543-561
Oil-field brines are the most favored ore-forming solutions for the sediment-hosted Mississippi Valley-type ore deposits. Detailed inorganic and organic chemical and isotope analyses of water and gas samples from six oil fields in central Mississippi, one of the very few areas...
