Morphology and age of fault scarps in the Rio Grande Rift, south-central Colorado
Steven M. Colman, William P. Rogers, R. M. Kirkham
William P. Rogers, Robert M. Kirkham, editor(s)
1986, Report, Contributions to Colorado Seisrnicity and Tectonics: A 1986 Update
Fault scarps in the Rio Grande rift of Colorado provide most of the evidence of paleoseismicity in the state, and are thus a major focus of assessments of earthquake hazards. Critical components of such assessments are the ages of past faulting events; age control is scarce and generally coarse for...
The non-transferability of a Cretaceous coal model in the San Juan Basin of New Mexico and Colorado
James E. Fassett
1986, GSA Special Papers (210) 155-171
The San Juan Basin of northwest New Mexico and southwest Colorado contains several Upper Cretaceous coal-bearing formations. The coals in these formations were deposited in environments associated with repeated transgressions and regressions of the Western Interior seaway in Late Cretaceous time. A detailed subsurface and surface study of the coal...
A population model for a long-lived, resprouting chaparral shrub: Adenostoma fasciculatum
Thomas J. Stohlgren, Philip W. Rundel
1986, Ecological Modelling (34) 245-257
Extensive stands of Adenostoma fasciculatum H.&A. (chamise) in the chaparral of California are periodically rejuvenated by fire. A population model based on size-specific demographic characteristics (thinning and fire-caused mortality) was developed to generate probable age distributions within size classes and survivorship curves for typical stands. The model was modified to...
Mississippi embayment aquifer system in Mississippi: Geohydrologic data compilation for flow model simulation
J. K. Arthur, R.E. Taylor
1986, Journal of the American Water Resources Association (22) 1021-1029
As part of the Gulf Coast Regional Aquifer System Analysis (GC RASA) study, data from 184 geophysical well logs were used to define the geohydrologic framework of the Mississippi embayment aquifer system in Mississippi for flow model simulation. Five major aquifers of Eocene and Paleocene age were defined within this...
Environmental regulation and influence of the eyes and pineal gland on the gonadal cycle and spawning in channel catfish (Ictalurus punctatus)
K. B. Davis, C. A. Goudie, B.A. Simco, R. MacGregor III, N. C. Parker
1986, Ecological and Evolutionary Physiology (59) 717-724
Blinded, pinealectomized, or blinded and pinealectomized female channel catfish (Ictalurus punctatus) were placed with normal (unoperated on) control fish in outdoor tanks at constant temperature (21 ± 2 C) or earthen ponds (ambient conditions) in February or August, when they were 21 or 27 mo old. Fish were sampled through...
Changing climate: Geothermal evidence from permafrost in the Alaskan Arctic
Arthur H. Lachenbruch, B. Vaughan Marshall
1986, Science (234) 689-696
Temperature profiles measured in permafrost in northernmost Alaska usually have anomalous curvature in the upper 100 meters or so. When analyzed by heat-conduction theory, the profiles indicate a variable but widespread secular warming of the permafrost surface, generally in the range of 2 to 4 Celsius degrees during the last...
Fire adaptation in Neblinaria celiae (Theaceae), a high-elevation rosette shrub endemic to a wet equatorial tepui
T.J. Givnish, R.W. McDiarmid, W.R. Buck
1986, Oecologia (70) 481-485
Neblinaria celiae (Theaceae), a rosette shrub endemic to the exceedingly rainy summit of remote Cerro de la Neblina in southern Venezuela, has a previously undescribed set of adaptations to fire. Its growth form entails sparse branching, massive terminal leaf rosettes, and thick bark. It is highly fire-tolerant, with a survival rate...
The Center Pond pluton: The restite of the story (phase separation and melt evolution in granitoid genesis)
T. A. Scambos, M.C. Loiselle, D. R. Wones
1986, American Journal of Science (286) 241-280
The Center Pond pluton is a calc-alkaline post-tectonic Acadian body intruding chlorite grade Silurian metasediments of E-central Maine. Mapping and petrographic work reveal that the pluton contains 5 igneous rock types; quartz diorite, hornblende-biotite granodiorite, biotite granite, porphyritic granite, and aplitic granite. The linearity of major and trace element trends...
Influence of welded boundaries in anelastic media on energy flow, and characteristics of P, S-I, and S-II waves: Observational evidence for inhomogeneous body waves in low-loss solids
Roger D. Borcherdt, Gary Glassmoyer, Leif Wennerberg
1986, Journal of Geophysical Research B: Solid Earth (91) 11503-11518
A general computer code, developed to calculate anelastic reflection-refraction coefficients, energy flow, and the physical characteristics for general P, S-I, and S-II waves, quantitatively describes physical characteristics for wave fields in anelastic media that do not exist in elastic media. Consideration of wave fields incident on boundaries between anelastic media shows that scattered...
Short-period strain (0.1–105 s): Near-source strain field for an earthquake (ML 3.2) near San Juan Bautista, California
M.J.S. Johnston, Roger D. Borcherdt, A. T. Linde
1986, Journal of Geophysical Research B: Solid Earth (91) 11497-11502
Measurements of dilational earth strain in the frequency band 25–10−5 Hz have been made on a deep borehole strainmeter installed near the San Andreas fault. These data are used to determine seismic radiation fields during nuclear explosions, teleseisms, local earthquakes, and ground noise during seismically quiet times. Strains of less than...
Landform modifications at a nuclear-waste burial site
J. R. Gray
1986, Conference Paper, Proceedings, Fourth Federal Interagency Sedimentation Conference: Interagency Advisory Committee on Water Data, Subcommittee on Sedimentation, Las Vegas
No abstract available....
Monitoring grizzly bear population trends
L.L. Eberhardt, R.R. Knight, B.M. Blanchard
1986, Journal of Wildlife Management (50) 613-618
A simple different equation model was developed to provide additional perspective on observed mortality and trend data on Yellowstone grizzly bears (Ursus arctos horribilis). Records of mortalities of adult females from 1959 to 1985 were utilized, in conjunction with data on females with cubs. The overall downward trend...
Introduction to stream network habitat analysis
John M. Bartholow, Terry J. Waddle
1986, Report
Increasing demands on stream resources by a variety of users have resulted in an increased emphasis on studies that evaluate the cumulative effects of basinwide water management programs. Network habitat analysis refers to the evaluation of an entire river basin (or network) by predicting its habitat response to alternative...
The temperature dependence of isothermal moisture vs. potential characteristics of soils
J. R. Nimmo, E.E. Miller
1986, Soil Science Society of America Journal (50) 1105-1113
A method has been developed for rapid, transient measurement of hysteretic soil-moisture characteristics as a function of temperature. While a varying soil-water pressure was imposed on a thin sample by means of flexible membranes held in firm contact with the soil, water content was measured by gamma-ray attenuation, and matric...
Theory, construction and operation of simple tensiometers
David I. Stannard
1986, Groundwater Monitoring and Remediation (6) 70-78
The tensiometer, introduced by Richards and Gardner (1936) has been a tool often ignored in unsaturated zone investigations. Hazardous waste disposal studies that require values of unsaturated zone matric potentials will expand tensiometer use. Familiarity with operation and installation principles is necessary to ensure quality data collection.The essential elements of...
Recovery of compacted soils in Mojave Desert ghost towns
Robert H. Webb, John W. Steiger, Howard G. Wilshire
1986, Soil Science Society of America Journal (50) 1341-1344
Residual compaction of soils was measured at seven sites in five Mojave Desert ghost towns. Soils in these Death Valley National Monument townsites were compacted by vehicles, animals, and human trampling, and the townsites had been completely abandoned and the buildings removed for 64 to 75 yr. The soils studied...
Hydrogeochemistry of sulfide and arsenic-rich tailings and alluvium along Whitewood Creek, South Dakota (Part 1 of 3 parts)
F. M. M. Morel, J. Rouse, J. L. Schnoor, M. G. Wolman, J. A. Cherry
1986, Mineral & Energy Resources (29)
During 100 years prior to 1977, Whitewood Creek, SD, received about 1 billion tons of arsenic-rich and sulfide-mineral rich tailings from gold mining operations. A hydrogeochemical investigation conducted in 1983-84 focused on four local study areas on the flood plain where tailings deposits exist on top of moderately permeable alluvium....
Recent developments in hydrologic instrumentation
Vito J. Latkovich, James C. Futrell II
Douglas L. Kane, editor(s)
1986, American Water Resources Association Technical Publication Series 86-1
The programs of the U.S. Geological Survey require instrumentation for collecting and monitoring hydrologic data in cold regions. The availability of space-age materials and implementation of modern electronics and mechanics is making possible the recent developments of hydrologic instrumentation, especially in the area of measuring streamflow under ice cover. Material...
Influence of nutrients on feed intake and condition of captive canvasbacks in winter
Matthew C. Perry, Wayne J. Kuenzel, Byron K. Williams, John A. Serafin
1986, Journal of Wildlife Management (50) 427-434
Dramatic changes in the food habits and distribution of canvasbacks (Aythya valisineria) in Chesapeake Bay during the 1970's generated a need to evaluate the nutritional value of food items and the requirements of this species on its wintering grounds. Groups of captive canvasbacks were maintained ad libitum on 5 diets...
An inverse method using toroidal mode data
C. Willis
1986, Inverse Problems (2) 111-130
The author presents a numerical method for calculating the density and S-wave velocity in the upper mantle of a spherically symmetric, non-rotating Earth which consists of a perfect elastic, isotropic material. The data comes from the periods of the toroidal oscillations. She tests the method...
Does pH affect fish species richness when lake area is considered?
P.J. Rago, J.G. Wiener
1986, Transactions of the American Fisheries Society (115) 438-447
Numerous surveys have shown that fish species richness (number of species) is positively correlated with lake pH. However, species richness of fish communities is also correlated with lake size, and low‐pH lakes are often small. Thus, conclusions drawn from examination of fish community structure relative to spatial...
Infectious pancreatic necrosis virus: Protocol for a standard challenge to brook trout
P. E. McAllister, W. J. Owens
1986, Transactions of the American Fisheries Society (115) 466-470
A protocol for experimental challenge with infectious pancreatic necrosis (IPN) virus was defined with brook trout Salvelinus fontinalis as the model species. Fish were exposed by immersion for 5 h in water containing IPN virus at a concentration of 105 plaque‐forming units per milliliter. We propose the protocol as a standard...
Decrease in deformation rate observed by two-color laser ranging in Long Valley caldera
Mark F. Linker, J. O. Langbein, Art McGarr
1986, Science (232) 213-216
After the January 1983 earthquake swarm, the last period of notable seismicity, the rapid rate of deformation of the south moat and resurgent dome of the Long Valley caldera diminished. Frequently repeated two-color laser ranging measurements made within a geodetic network in the caldera during the interval June 1983 to...
Cavity-nesting birds and the cavity-tree resource in plains cottonwood bottomlands
James A. Sedgwick, Fritz L. Knopf
1986, Journal of Wildlife Management (50) 247-252
Densities of, and potential nesting substrates for, cavity-nesting birds were examined in a mature plains cottonwood (Populus sargentii) community in northeastern Colorado. Although snag (dead tree) densities were low (0.66/ha), the cavity-nesting guild included 7 species with densities ≤ 463 birds/100 ha. This finding suggests that cavity nesters...
Parasitization of meadow voles, Microtus pennsylvanicus (ORD), by American dog ticks, Dermacentor variabilis (Say), and adult tick movement during high host density
J. F. Carroll, J.D. Nichols
1986, Journal of Entomological Science (21) 102-113
The numbers of host-seeking adult American dog ticks, Dermacentor variabilis (Say), in a sweet gum field in Maryland reflected changes in the population density of a host species, the meadow vole, Microtus pennsylvanicus (Ord), which within 1.5 yr fell from an estimated 157 to 8 voles on a 0.8 ha grid. During high vole...
