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1 Fernandez, Diego P.Lowering the detection limit for arsenic: implications for a future practical quantitation limitExposure to arsenic (As) in drinking water is associated with an increased risk ol bladder, liver, kidney, ,ind skin cancers (Smith et al, 2002; NRG DIEGO P. FERNANDEZ, 2001). To mitigate these risks? the US Environmental Protection Agency AND JANET G. HERING (USEPA) revised the maximum contaminant ...Practical quantitation limit; Chlorine2007
2 Jarrard, Richard D.Data report: high-resolution mineralogy for leg 199 based on reflectance spectroscopy and physical propertiesDuring Ocean Drilling Program Leg 199 in the equatorial Pacific, visible and near-infrared spectroscopy (VNIS) was used to measure the reflectance spectra (350?2500 nm) of 1343 sediment samples. Reflectance spectra were also measured for a suite of 60 samples of known mineralogy, thereby providing a...2004
3 Hu, LihaiTrace elements in the hairStudy of uneven distribution of trace elements in elephant hair and compare the result with animal horns.2013
4 Thorne, Michael S.Viterbi sparse spike detectionAccurate interpretation of seismic traveltimes and amplitudes in the exploration and global scales is complicated by the band-limited nature of seismic data. We discovered a stochastic method to reduce a seismic waveform into a most probable constituent spike train. Model waveforms were constructed ...2013-01-01
5 Jarrard, Richard D.Origin of seismic reflectors within carbonate-rich sediments from northeastern Australian marginWe use continuous velocity records from 12 sites and continuous density records from 9 sites from Ocean Drilling Program (ODP) Leg 133 to examine both direct and indirect controls on seismic reflectors and depth-to-time conversion for the northeastern Australian margin. In these carbonate-rich sedim...1993
6 Zhdanov, Michael S.Focusing geophysical inversion imagesA critical problem in inversion of geophysical data is developing a stable inverse problem solution that can simultaneously resolve complicated geological structures. The traditional way to obtain a stable solution is based on maximum smoothness criteria. This approach, however, provides smoothe...Focusing; Geophysical inversion images; Minimum gradient support functionals; MGS1999
7 Brown, Francis HaroldDatingThere are basically three lines of investigation that are involved in geochronology ? the dating of rocks and other earth materials. First, there are the physical and chemical dating methods which give us numerical estimates of age. Second, there is the reconstruction of the order of events in sec...1984
8 Zhdanov, MichaelLarge-scale 3D inversion of marine magnetotelluric data: Case study from the Gemini prospect, Gulf of MexicoThree-dimensional magnetotelluric (MT) inversion is an emerging technique for offshore hydrocarbon exploration. We have developed a new approach to the 3D inversion of MT data, based on the integral equation method. The Tikhonov regularization and physical constraint have been used to obtain a stab...2011
9 Jarrard, Richard D.Electrical properties of basalts from Sites 768 and 770Conductivity of 54 basalt samples from ODP Sites 768 and 770 was measured as a function of temperature and fluid salinity. Porosity was also measured for all samples, and cation exchange capacity was measured for 46 of the samples. Porosity measurements indicated that porosity is underestimated fo...1991
10 Jewell, PaulControls of tufa development in Pleistocene Lake Bonneville, UtahProminent tufa localities along the Provo level (∼14,000 14C yr B.P.) shoreline in Pleistocene Lake Bonneville have been characterized in detail. Three types of tufa are recognized: capping tufa, beachrock, and capping tufa over beachrock. Capping tufa and beachrock are end members of a continuum ...Tufa; Pleistocene; Pluvial lakes2006
11 Jewell, PaulCirculation, salinity, and dissolved oxygen in the Cretaceous North American seawayCritical paleoceanographic problems regarding the maximum transgressive phase of the Cretaceous North American seaway have been studied with a three-dimensional ocean circulation model. Four simulations employing minimum and maximum solar insolation winds from the Cretaceous and a wide range of pre...Cretaceous North American Seaway1996
12 Zhdanov, Michael3D inversion of airborne electromagnetic dataTime-domain airborne surveys gather hundreds of thousands of multichannel, multicomponent samples. The volume of data and other complications have made 1D inversions and transforms the only viable method to interpret these data, in spite of their limitations. We have developed a practical methodolog...2012-01-01
13 Zhdanov, MichaelCross-well electromagnetic imaging in three dimensionsIn this paper, we develop a new technique for 3D cross-well electromagnetic tomography, based on an EM borehole survey consisting of a moving vertical magnetic dipole transmitter, located in one or several boreholes, and a tri-axial induction receiver, located in the other boreholes. The method is b...2003
14 Brown, Francis HaroldSome early pleistocene deposits of the lower Omo valley: the Usno formationEarly Pleistocene deposits of the Rudolf Basin have been described by E. Brumpt (Bourg de Bozas, 1903: 107 ff.), Arambourg (1943: 190 ff.), Fuchs (1939), Patterson (1966), and Butzer and Thurber (1969). These include the Omo Beds, first recognized by Brumpt in 1902 and subsequently studied by Arambo...1969
15 Jarrard, Richard D.Velocity and density of carbonate-rich sediments from northeastern Australian margin: integration of core and log dataDuring Ocean Drilling Program (ODP) Leg 133, shipboard scientists obtained a remarkable quantity of both core and log measurements of the physical properties of carbonate-rich sediments. This suite of measurements provides a unique opportunity to evaluate the robustness of each measurement technique...1993
16 Zhdanov, Michael S.3-D magnetic inversion with data compression and image focusingWe develop a method of 3-D magnetic anomaly inversion based on traditional Tikhonov regularization theory. We use a minimum support stabilizing functional to generate a sharp, focused inverse image. An iterative inversion process is constructed in the space of weighted model parameters that acce...2002-01-01
17 Jarrard, Richard D.The magnetostratigraphy of ocean drilling program leg 105 sedimentsDuring Leg 105 of the Ocean Drilling Program, a series of 11 holes was drilled at three sites along a north-south transect in Baffin Bay and the Labrador Sea. Intermittent recovery and drilling disturbance, resulting in part from the harsh weather conditions encountered, hampered magnetostratigraph...1989
18 Chapman, David S.Exhumation of the central Wasatch Mountains, Utah: 1, Patterns and timing of exhumation deduced from low-temperature thermochronology dataThe Wasatch Mountains are often cited as an example of normal fault growth and footwall flexure. They represent a tilted footwall at the edge of the Basin and Range extensional province, a major rift basin. Thus understanding the detailed spatial and elevation changes in coupled thermochronometer da...Uplift; Exhumation; Wasatch Fault; Wasatch Mountains; Utah; Helium dating; Fission track; Tectonophysics; Extensional tectonics; Geothermal observations2002
19 Brown, Francis HaroldGeological development of the Omo-Turkana Basin during the pliocene and pleistocene epochsPliocene and Pleistocene deposits of the Omo-Turkana Basin extend from 6?N latitude to about 2?N latitude (-450 km), and laterally from about 35.5?E to 36.5?E. Sediments are brought to the basin by the Omo River which rises in Ethiopia, and by the Turkwel and Kerio Rivers which rise in Kenya and Uga...2004
20 Jarrard, Richard D.Geometry of Pleistocene facies on the Great Barrier Reef outer shelf and upper slope - seismic stratigraphy of sites 819, 820, and 821Seismic stratigraphic analysis of the sedimentary succession intersected in Ocean Drilling Program (ODP) Sites 819, 820, and 821, on the outer shelf and upper slope seaward of the Great Barrier Reef, provides a clear indication of the importance of sediment supply and depositional base-level as two ...1993
21 Jarrard, Richard D.Resistivity/porosity/velocity relationships from downhole logs: an aid for evaluating pore morphologyRelationships between downhole resistivity/velocity logs and porosity styles, controlled by cementation/dissolution/recrystallization, are investigated using core and downhole logging data from the carbonate-rich sediments encountered during Leg 133 of the Ocean Drilling Program (ODP), northeastern ...1993
22 Jarrard, Richard D.Sedimentary response to paleoclimate from downhole logs at Site 693, Antarctic Continental MarginThe first well logs collected below the Antarctic circle were obtained during Leg 113 at Site 693 on the Dronning Maud Land Margin (Antarctica) in the Weddell Sea. Gamma-ray, resistivity, and sonic logs were collected between 108.0 and 439.0 mbsf. The downhole logs show good agreement with the data...1990
23 Zhdanov, MichaelTwo-dimensional magnetotelluric inversion of blocky geoelectrical structuresThis paper demonstrates that there are alternative approaches to the magnetotelluric (MT) inverse problem solution based on different types of geoelectrical models. The traditional approach uses smooth models to describe the conductivity distribution in underground formations. In this paper, we pres...2002-01-01
24 Solomon, Douglas KipTracer applications of noble gas radionuclides in the geosciencesNoble gas radionuclides, including 81Kr (t1/2 = 229,000 yr), 85Kr (t1/2 = 10.8 yr), and 39Ar (t1/2 = 269 yr), possess nearly ideal chemical and physical properties for studies of earth and environmental processes. Recent advances in Atom Trap Trace Analysis (ATTA), a laser-based atom counting method...2014-01-01
25 Jarrard, Richard D.Geophysical properties of oceanic crust at Sites 768 and 770Velocity, density, resistivity, and neutron-porosity logs were recorded in virtually the entire 222-m-thick section of basaltic back-arc crust drilled at Site 768 and through the 106-m section of MORB crust at Site 770. Our analysis of these logs and comparison with measurements on discrete cores pe...1991
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