Development of a practical diet for juvenile striped bass
S. G. Hughes, C. A. Lemm, R. L. Herman
1992, Transactions of the American Fisheries Society (121) 802-809
We formulated four diets that simulated the amino acid profiles of eggs of striped bass Morone saxatilis, carcasses of larval striped bass, eggs of rainbow trout Oncorhynchus mykiss, or nauplii of Artemia salina; a fifth diet contained a high concentration (33.6%) of shrimp meal. These diets were fed to juvenile striped bass for...
A comparison of surface-grab and cross sectionally integrated stream-water-quality sampling methods
G. R. Martin, J. L. Smoot, K. D. White
1992, Water Environment Research (64) 866-876
Stream sampling for water quality data has commonly employed simple surface-grab procedures as opposed to more involved, cross sectionally integrated techniques. Paired samples for analysis of selected constituents were collected over various flow conditions at four sites to evaluate differences between the two sampling methods. Concentrations of dissolved constituents were...
Global change and coral reef ecosystems
S. V. Smith, R. W. Buddemeier
1992, Annual Review of Ecology and Systematics (23) 89-118
No abstract available....
Forecast of earthquake in western Nicaragua
David H. Harlow, Randall A. White
1992, Science (258) 726-726
No abstract available....
New links between the Chicxulub impact structure and the Cretaceous/Tertiary boundary
Virgil L. Sharpton, G. B. Dalrymple, L.E. Marin, G. Ryder, B.C. Schuraytz, J. Urrutia-Fucugauchi
1992, Nature (359) 819-821
The 200-km-diameter Chicxulub structure1–3 in northern Yucatan, Mexico has emerged as the prime candidate for the Cretaceous/Tertiary (K/T) boundary impact crater3–6. Concentric geophysical anomalies associated with enigmatic occurrences of Upper Cretaceous breccias and andesitic rocks led Penfield and Camargo1 to suspect that this structure was a buried impact basin. More recently, the...
Enhanced visualization for the interpretation of Magellan radar data: Supplement to the Magellan special issue
Randolph L. Kirk, Laurence A. Soderblom, Ella M. Lee
1992, Journal of Geophysical Research E: Planets (97) 16371-16380
The differences of radar data from more familiar photographic images, coupled with the unique geologic characteristics of Venus's surface, can make interpretation of the standard Magellan data products difficult for both planetary scientists and nonspecialists. We describe a set of digital processing techniques for transforming individual remote‐sensing datasets in order...
Creep, compaction and the weak rheology of major faults
Norman H. Sleep, M.L. Blanpied
1992, Nature (359) 687-692
Field and laboratory observations suggest that the porosity within fault zones varies over earthquake cycles so that fluid pressure is in long-term equilibrium with hydrostatic fluid pressure in the country rock. Between earthquakes, ductile creep compacts the fault zone, increasing fluid pressure, and finally allowing frictional failure at relatively low...
Modeling tidal exchange and dispersion in Boston Harbor
Richard P. Signell, Bradford Butman
1992, Journal of Geophysical Research C: Oceans (97) 15591-15606
Tidal dispersion and the horizontal exchange of water between Boston Harbor and the surrounding ocean are examined with a high-resolution (200 m) depth-averaged numerical model. The strongly varying bathymetry and coastline geometry of the harbor generate complex spatial patterns in the modeled tidal currents which are verified by shipboard acoustic...
A sharp and flat section of the core-mantle boundary
J.E. Vidale, H.M. Benz
1992, Nature (359) 627-629
The transition zone between the Earth's core and mantle plays an important role as a boundary layer for mantle and core convection1. This zone conducts a large amount of heat from the core to the mantle, and contains at least one thermal boundary layer2,3; the proximity of reactive silicates and...
Deep-living microbes mount a relentless attack on rock
T. Appenzeller
1992, Science (258) 222-222
No abstract available....
Continuous 500,000-year climate record from vein calcite in Devils Hole, Nevada
I.J. Winograd, T.B. Coplen, J.M. Landwehr, A.C. Riggs, Kenneth R. Ludwig, Barney J. Szabo, Peter T. Kolesar, K.M. Revesz
1992, Science (258) 255-260
Oxygen-18 (δ18O) variations in a 36-centimeter-long core (DH-11) of vein calcite from Devils Hole, Nevada, yield an uninterrupted 500,000-year paleotemperature record that closely mimics all major features in the Vostok (Antarctica) paleotemperature and marine δ18O ice-volume records. The chronology for this continental record is based on 21 replicated mass-spectrometric uranium-series...
Mass-spectrometric 230Th-234U-238U dating of the Devils Hole calcite vein
K.R. Ludwig, K. R. Simmons, Barney J. Szabo, I.J. Winograd, J.M. Landwehr, A.C. Riggs, R.J. Hoffman
1992, Science (258) 284-287
The Devils Hole calcite vein contains a long-term climatic record, but requires accurate chronologic control for its interpretation. Mass-spectrometric U-series ages for samples from core DH-11 yielded 230Th ages with precisions ranging from less than 1,000 years (2σ) for samples younger than ∼140 ka (thousands of years ago) to less than...
Time and metamorphic petrology: Calcite to aragonite experiments
B. R. Hacker, S. H. Kirby, S.R. Bohlen
1992, Science (258) 110-112
Although the equilibrium phase relations of many mineral systems are generally well established, the rates of transformations, particularly in polycrystalline rocks, are not. The results of experiments on the calcite to aragonite transformation in polycrystalline marble are different from those for earlier experiments on powdered and single-crystal calcite. The transformation...
Global Land Information System (GLIS): user manual
EROS Data Center
1992, Report
No abstract available....
Assessing nonpoint sources of toxicity Part II: using biomonitoring techniques
Del Wayne Nimmo, John Karish, Heidi Bestgen, Trudy Steidl-Pulley, Mary Willox, Terri Craig, Carla Castle
1992, Park Science (12) 6-8
No abstract available....
Early Miocene hydrothermal activity at Pachuca-Real del Monte, Mexico; an example of space-time association of volcanism and epithermal Ag-Au vein mineralization
Edwin H. McKee, John E. Dreier, Donald C. Noble
1992, Economic Geology (87) 1635-1637
No abstract available....
Pliocene paleoclimatic interpretation of DSDP Site 580 (NW Pacific) using diatoms
John A. Barron
1992, Marine Micropaleontology (20) 23-44
High-resolution quantitative diatom data are tabulated for the early part of the late Pliocene (3.25 to 2.08 Ma) at DSDP Site 580 in the northwestern Pacific. Sample spacing averages 11 k.y. between 3.1 and 2.8 Ma, but increases to 14 to 19 k.y. prior to 3.1 Ma and after 2.8...
Interaction assessment II: A tool for population and community management
John M. Emlen, D. Carl Freeman, Mark B. Bain, Judy Li
1992, Journal of Wildlife Management (56) 708-717
To successfully preserve or manage a species, we must understand how the community of which it is a part functions. We must know how environmental alterations affect the fitness not only of the species of interest, but also that of its competitors, predators, and prey; and we must know the...
Evaluating habitat selection with radio-telemetry triangulation error
Michael D. Samuel, Kevin P. Kenow
1992, Journal of Wildlife Management (56) 725-734
Radio-telemetry triangulation errors result in the mislocation of animals and misclassification of habitat use. We present analytical methods that provide improved estimates of habitat use when misclassification probabilities can be determined. When misclassification probabilities cannot be determined, we use random subsamples from the error distribution of an estimated animal location...
Evaluating habitat selection with radio-telemetry triangulation error
Michael Samuel, Kevin P. Kenow
1992, Journal of Wildlife Management (56) 725-734
Radio-telemetry triangulation errors result in the mislocation of animals and misclassification of habitat use. We present analytical methods that provide improved estimates of habitat use when misclassification probabilities can be determined. When misclassification probabilities cannot be determined, we use random subsamples from the error distribution of an estimated animal location...
A geochemical transport model for redox-controlled movement of mineral fronts in groundwater flow systems: A case of nitrate removal by oxidation of pyrite
Peter Engesgaard, Kenneth L. Kipp
1992, Water Resources Research (28) 2829-2843
A one-dimensional prototype geochemical transport model was developed in order to handle simultaneous precipitation-dissolution and oxidation-reduction reactions governed by chemical equilibria. Total aqueous component concentrations are the primary dependent variables, and a sequential iterative approach is used for the calculation. The model was verified by analytical and numerical comparisons and...
Modeling biotic uptake by periphyton and transient hyporrheic storage of nitrate in a natural stream
Brian K.A. Kim, Alan P. Jackman, Frank J. Triska
1992, Water Resources Research (28) 2743-2752
To a convection-dispersion hydrologic transport model we coupled a transient storage submodel (Bencala, 1984) and a biotic uptake submodel based on Michaelis-Menten kinetics (Kim et al., 1990). Our purpose was threefold: (1) to simulate nitrate retention in response to change in load in a third-order stream, (2) to differentiate biotic...
Geologic implications of earthquake source parameters in central and eastern North America
R. L. Wheeler, A. C. Johnston
1992, Seismological Research Letters (63) 491-514
The relations between geology and earthquakes remain mostly enigmatic in North America east of the Rocky Mountains. Hypocentral depths and the dips of rupture zones (preferred nodal planes) are among the seismological variables most likely associated with geologic structure in the stable continental region (SCR) of central and eastern North...
Estimation of wildlife population ratios incorporating survey design and visibility bias
Michael D. Samuel, R. Kirk Steinhorst, Edward O. Garton, James W. Unsworth
1992, Journal of Wildlife Management (56) 718-725
Age and sex ratio statistics are often a key component of the evaluation and management of wildlife populations. These statistics are determined from counts of animals that are commonly plagued by errors associated with either survey design or visibility bias. We present age and sex ratio estimators that incorporate both...
Isotopic signatures of black tektites from the K‐T boundary on Haiti: Implications for the age and type of source material
Wayne R. Premo, G. A. Izett
1992, Meteoritics (27) 413-423
U‐Th‐Pb, Rb‐Sr, and Sm‐Nd isotopic signatures of corroded, but unaltered, black glassy tektites from Cretaceous‐Tertiary (K‐T) boundary rock on Haiti are not consistent with their derivation from an impact on MOR‐derived oceanic crust or continental regions involving middle Proterozoic or older crustal material. Two single‐grain and two batches of these...
