Before and after retrofit - response of a building during ambient and strong motions
M. Çelebi, Huaibao P. Liu
Jones N.P., editor(s)
1998, Journal of Wind Engineering and Industrial Aerodynamics (77-78) 259-268
This paper presents results obtained from ambient vibration and strong-motion responses of a thirteen-story, moment-resisting steel framed Santa Clara County Office Building (SCCOB) before being retrofitted by visco-elastic dampers and from ambient vibration response following the retrofit. Understanding the cumulative structural and site characteristics that affect the response of SCCOB...
Heat flow and thermal history of the Anadarko basin, Oklahoma
L.S. Carter, S.A. Kelley, D.D. Blackwell, N. D. Naeser
1998, American Association of Petroleum Geologists Bulletin (82) 291-316
New heat-flow values for seven sites in the Anadarko basin, Oklahoma, were determined using high-precision temperature logs and thermal conductivity measurements from nearly 300 core plugs. Three of the sites are on the northern shelf, three sites are in the deep basin, and one site is in the frontal fault...
Pre-eruptive volatile content, melt-inclusion chemistry, and microthermometry of interplinian Vesuvius lavas (pre-AD 1631)
H. E. Belkin, B. de Vivo, K. Torok, J.D. Webster
1998, Journal of Volcanology and Geothermal Research (82) 79-95
Silicate-melt inclusions from lavas and pyroclastics from a selected suite of pre-A.D. 1631 interplinian Mt. Somma-Vesuvius lavas and scoria have been experimentally homogeneized and studied by microthermometry, electron microprobe (EMPA) and secondary-ion mass spectrometry (SIMS) to examine pre-eruptive volatile content and magma evolution. The melt inclusions have a bubble about...
Consolidation patterns during initiation and evolution of a plate-boundary decollement zone: Northern Barbados accretionary prism
J.C. Moore, A. Klaus, N.L. Bangs, B. Bekins, C.J. Bucker, W. Bruckmann, S.N. Erickson, O. Hansen, T. Horton, P. Ireland, C.O. Major, Gregory F. Moore, S. Peacock, S. Saito, E.J. Screaton, J.W. Shimeld, P.H. Stauffer, T. Taymaz, P.A. Teas, T. Tokunaga
1998, Geology (26) 811-814
Borehole logs from the northern Barbados accretionary prism show that the plate-boundary decollement initiates in a low-density radiolarian claystone. With continued thrusting, the decollement zone consolidates, but in a patchy manner. The logs calibrate a three-dimensional seismic reflection image of the decollement zone and indicate which portions are of low...
Flow of river water into a karstic limestone aquifer: 2. Dating the young fraction in groundwater mixtures in the Upper Floridan aquifer near Valdosta, Georgia
Niel Plummer, E. Busenberg, S. Drenkard, P. Schlosser, B. Ekwurzel, R. Weppernig, J. B. McConnell, R. L. Michel
1998, Applied Geochemistry (13) 1017-1043
Tritium/helium-3 (3H/3He) and chlorofluorocarbon (CFCs, CFC–11, CFC–12, CFC–113) data are used to date the young fraction in groundwater mixtures from a karstic limestone aquifer near Valdosta, Georgia, where regional paleowater in the Upper Floridan aquifer receives recharge from two young sources—the flow of Withlacoochee River water through sinkholes in the...
Near-surface structural model for deformation associated with the February 7, 1812, New Madrid, Missouri, earthquake
J. K. Odum, W. J. Stephenson, K. M. Shedlock, T. L. Pratt
1998, Geological Society of America Bulletin (110) 149-162
The February 7, 1812, New Madrid, Missouri, earthquake (M [moment magnitude] 8) was the third and final large-magnitude event to rock the northern Mississippi Embayment during the winter of 1811–1812. Although ground shaking was so strong that it rang church bells, stopped clocks,...
A polygenetic model for pedostratigraphic units in the Chinese loess Plateau Region
Hongfang Wang, L.R. Follmer
1998, Quaternary International (51-52) 52
[No abstract available]...
Geochemical and isotopic (Nd-Pb-Sr-O) variations bearing on the genesis of volcanic rocks from Vesuvius, Italy
R. A. Ayuso, B. de Vivo, G. Rolandi, R.R. Seal II, A. Paone
1998, Journal of Volcanology and Geothermal Research (82) 53-78
Alkaline volcanism produced by Monte Somma-Vesuvius volcano includes explosive plinian and subplinian activity in addition to effusive lava flows. Pumice, scoria, and lava (150 samples) exhibit major- and trace-element gradients as a function of SiO2 (58.9-47.2 wt%) and MgO (0-7.8 wt%); Mg value are ???50. Internally gradational chemical groups or...
Drought-induced shift of a forest-woodland ecotone: Rapid landscape response to climate variation
Craig D. Allen, David D. Breshears
1998, Proceedings of the National Academy of Sciences of the United States of America (95) 14839-14842
In coming decades, global climate changes are expected to produce large shifts in vegetation distributions at unprecedented rates. These shifts are expected to be most rapid and extreme at ecotones, the boundaries between ecosystems, particularly those in semiarid landscapes. However, current models do not adequately provide for such rapid effects—particularly...
Three-dimensional seismic structure and moment tensors of non-double-couple earthquakes at the Hengill-Grensdalur volcanic complex, Iceland
A.D. Miller, B.R. Julian, G.R. Foulger
1998, Geophysical Journal International (133) 309-325
The volcanic and geothermal areas of Iceland are rich sources of non-double-couple (non-DC) earthquakes. A state-of-the-art digital seismometer network deployed at the Hengill–Grensdalur volcanic complex in 1991 recorded 4000 small earthquakes. We used the best recorded of these to determine 3-D VP and VP /VS structure tomographically and accurate earthquake moment...
Cretaceous plutonic rocks in the Donner Lake-Cisco Grove area, northern Sierra Nevada, California
Matthew J. Kulow, Richard E. Hanson, Gary H. Girty, Melissa S. Girty, David S. Harwood
1998, The Compass: Earth Science Journal of Sigma Gamma Epsilon (74) 69-76
The northernmost occurrences of extensive, glaciated exposures of the Sierra Nevada batholith occur in the Donner Lake-Cisco Grove area of the northern Sierra Nevada. The plutonic rocks in this area, which are termed here the Castle Valley plutonic assemblage, crop out over an area of 225 km2 and for the...
Estimation of the intrinsic absorption and scattering attenuation in Northeastern Venezuela (Southeastern Caribbean) using coda waves
F. Ugalde, L.G. Pujades, J.A. Canas, A. Villasenor
1998, Pure and Applied Geophysics (153) 685-702
Northeastern Venezuela has been studied in terms of coda wave attenuation using seismograms from local earthquakes recorded by a temporary short-period seismic network. The studied area has been separated into two subregions in order to investigate lateral variations in the attenuation parameters. Coda-Q-1 (Q(c)-1) has been obtained using the single-scattering...
Mesoscale disturbance and ecological response to decadal climatic variability in the American Southwest
T.W. Swetnam, J.L. Betancourt
1998, Journal of Climate (11) 3128-3147
Ecological responses to climatic variability in the Southwest include regionally synchronized fires, insect outbreaks, and pulses in tree demography (births and deaths). Multicentury, tree-ring reconstructions of drought, disturbance history, and tree demography reveal climatic effects across scales, from annual to decadal, and from local (<102 km2) to mesoscale (104-106 km2)....
Sorrption of aquatic fulvic acid on streambed iron oxides: In-stream reaction rates and chemical fractionation
Diane M. McKnight, G. Hornberger, K. Bencala
1998, ACS Division of Environmental Chemistry, Preprints (38) 62-63
[No abstract available]...
Calcite crystal growth inhibition by organic acids isolated from the Florida Everglades
A.R. Hoch, M.M. Reddy, G. R. Aiken
1998, ACS Division of Environmental Chemistry, Preprints (38) 78-81
[No abstract available]...
Sponges of the Permian Upper Capitan Limestone Guadalupe Mountains, New Mexico and Texas
J.K. Rigby, B. Senowbari-Daryan, H. Liu
1998, Brigham Young University Geology Studies (43) 19-89
Demosponge "sphinctozoans" and inozoid calcareous sponges are major constituents of the Upper Permian, Upper Capitan Limestone in the Guadalupe Mountains of New Mexico and Texas. Systematic description, taxonomy, and the stratigraphic distribution of these sponges are documented in collections from exposures of the Upper Capitan Limestone in the vicinity of...
A note on conservative transport in anisotropic, heterogeneous porous media in the presence of small-amplitude transients
R.L. Naff
1998, Water Resources Research (34) 3693-3699
The late-time macrodispersion coefficients are obtained for the case of flow in the presence of a small-scale deterministic transient in a three-dimensional anisotropic, heterogeneous medium. The transient is assumed to affect only the velocity component transverse to the mean flow direction and to take the form of a periodic function....
A new view into the Cascadia subduction zone and volcanic arc: Implications for earthquake hazards along the Washington margin
T. Parsons, A.M. Trehu, J.H. Luetgert, K. Miller, F. Kilbride, R.E. Wells, M. A. Fisher, E. Flueh, Uri S. ten Brink, N.I. Christensen
1998, Geology (26) 199-202
In light of suggestions that the Cascadia subduction margin may pose a significant seismic hazard for the highly populated Pacific Northwest region of the United States, the U.S. Geological Survey (USGS), the Research Center for Marine Geosciences (GEOMAR), and university collaborators collected and interpreted a 530-km-long wide-angle onshore-offshore seismic transect...
An empirical model of the tidal currents in the Gulf of the Farallones
J.M. Steger, C. A. Collins, F.B. Schwing, M. Noble, N. Garfield, M.T. Steiner
1998, Deep-Sea Research Part II: Topical Studies in Oceanography (45) 1471-1505
Candela et al. (1990, 1992) showed that tides in an open ocean region can be resolved using velocity data from a ship-mounted ADCP. We use their method to build a spatially varying model of the tidal currents in the Gulf of the Farallones, an area of complicated bathymetry where the...
Assessing the bioaccumulation of contaminants from sediments of the Upper Mississippi River using field-collected oligochaetes and laboratory- exposed Lumbriculus variegatus
E.L. Brunson, T.J. Canfield, F.J. Dwyer, C.G. Ingersoll, N.E. Kemble
1998, Archives of Environmental Contamination and Toxicology (35) 191-201
Concern with the redistribution of contaminants associated with sediment in the upper Mississippi River (UMR) arose after the flood of 1993. This project is designed to evaluate the status of sediments in the UMR and is one article in a series designed to assess the extent of sediment contamination in...
Partial eclogitization of the Ambolten gabbro-norite, north-east Greenland Caledonides
J. A. Gilotti, S. Elvevold
1998, Schweizerische Mineralogische und Petrographische Mitteilungen (78) 273-292
No abstract available....
In situ determination of particle friction angles of fluvial gravels
Christopher E. Johnston, E.D. Andrews, John Pitlick
1998, Water Resources Research (34) 2017-2030
Particle friction angles Φ represent the physical resistance to initial movement of a sediment particle and are therefore useful for relating initiation of motion to particular flows. We determined over 8000 friction angle values at five natural rivers by applying a new method that uses a digital load cell to...
Controls on denitrification in riparian soils in headwater catchments of a hardwood forest in the Catskill Mountains, U.S.A.
J.A. Ashby, W.B. Bowden, Peter S. Murdoch
1998, Soil Biology and Biochemistry (30) 853-864
Denitrification in riparian soils is thought to be an important factor that reduces hydrologic export of nitrate from forested and agricultural catchments. A 2-y study to identify the soil factors most closely associated with denitrification in riparian soils in headwater catchments within the Catskill Mountains of New York, included field...
Settlement rate of lead shot in tundra wetlands
Paul L. Flint
1998, Journal of Wildlife Management (62) 1099-1102
Several species of breeding waterfowl have been shown to be exposed to lead shot on the Yukon-Kuskokwim (Y-K) Delta, Alaska. I 'seeded' experimental plots with number 4 lead shot to determine the settlement rate of shot in wetland types commonly used by foraging waterfowl. I resampled plots for 3 years,...
Observations of wind-generated shoreface currents off Duck, North Carolina
J. P. Xu, L.D. Wright
1998, Journal of Coastal Research (14) 610-619
Wind, wave and currents measurements at 9 and 14 meter water depths on the shoreface off U.S. Army Corps of Engineers Field Research Facility at Duck, North Carolina are presented. Coastal setup accompanied by southerly-setting alongshore currents and seaward cross-shore currents is developed during Northeasterly storms. Coastal setdown, with reversal...
