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Geology topics

Howard E. Taylor

Publications and source records attributed to Howard E. Taylor.

At least 73 records · Page 4Linked to original sources
USGS2001

Toward linking maize chemistry to archaeological agricultural sites in the North American Southwest

Maize (Zea mays L.) was the staple domestic food crop for Ancestral Pueblo people throughout the northern American Southwest. It is thought to have been the basic food of the inhabitants of Chaco Canyon. New Mexico, a location that was a major centre of Ancestral Pueblo building and population during the 11th and early 12th centuries AD. Modern heirloom varieties of Native American corn have been difficult to grow in experimental fields in Chaco Canyon. Given an abundance of apparent storage structures in Chacoan buildings, it is possible that some corn recovered from archaeological contexts, was imported from surrounding areas. The ultimate goal of this research is to determine whether the corn in Chaco Canyon was grown locally or imported. This paper establishes the feasibility of a method to accomplish this goal. This study reports the results of using inductively coupled plasma-mass spectrometric (ICP-MS) instrumentation to determine chemical constituents of experimental fields and modern heirloom varieties of Native American corn. Analysis of 19 elements is adequate to differentiate soil and corn from three field areas. These results are promising: however, a number of problems, including post-depositional alterations in maize, remain to be solved. ?? 2001 Academic Press.

Journal of Archaeological Science↗
USGS2001

Distribution of inorganic mercury in Sacramento River water and suspended colloidal sediment material

The concentration and distribution of inorganic Hg was measured using cold-vapor atomic fluorescence spectrometry in samples collected at selected sites on the Sacramento River from below Shasta Dam to Freeport, CA, at six separate times between 1996 and 1997. Dissolved (ultrafiltered, 0.005 μm equivalent pore size) Hg concentrations remained relatively constant throughout the system, ranging from the detection limit (< 0.4 ng/L) to 2.4 ng/L. Total Hg (dissolved plus colloidal suspended sediment) concentrations ranged from the detection limit at the site below Shasta Dam in September 1996 to 81 ng/L at the Colusa site in January 1997, demonstrating that colloidal sediment plays an important role in the downriver Hg transport. Sequential extractions of colloid concentrates indicate that the greatest amount of Hg associated with sediment was found in the “residual” (mineral) phase with a significant quantity also occurring in the “oxidizable” phase. Only a minor amount of Hg was observed in the “reducible” phase. Dissolved Hg loads remained constant or increased slightly in the downstream direction through the study area, whereas the total inorganic Hg load increased significantly downstream especially in the reach of the river between Bend Bridge and Colusa. Analysis of temporal variations showed that Hg loading was positively correlated to discharge.

Archives of Environmental Contamination and Toxico↗
USGS2001

Standard reference water samples for rare earth element determinations

Standard reference water samples (SRWS) were collected from two mine sites, one near Ophir, CO, USA and the other near Redding, CA, USA. The samples were filtered, preserved, and analyzed for rare earth element (REE) concentrations (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) by inductively coupled plasma-mass spectrometry (ICP-MS). These two samples were acid mine waters with elevated concentrations of REEs (0.45–161 μg/l). Seventeen international laboratories participated in a ‘round-robin’ chemical analysis program, which made it possible to evaluate the data by robust statistical procedures that are insensitive to outliers. The resulting most probable values are reported. Ten to 15 of the participants also reported values for Ba, Y, and Sc. Field parameters, major ion, and other trace element concentrations, not subject to statistical evaluation, are provided.

Applied Geochemistry↗
USGS2001

Major-ion chemistry of the Rocky Mountain snowpack, USA

During 1993-97, samples of the full depth of the Rocky Mountain snowpack were collected at 52 sites from northern New Mexico to Montana and analyzed for major-ion concentrations. Concentrations of acidity, sulfate, nitrate, and calcium increased from north to south along the mountain range. In the northern part of the study area, acidity was most correlated (negatively) with calcium. Acidity was strongly correlated (positively) with nitrate and sulfate in the southern part and for the entire network. Acidity in the south exceeded the maximum acidity measured in snowpack of the Sierra Nevada and Cascade Mountains. Principal component analysis indicates three solute associations we characterize as: (1) acid (acidity, sulfate, and nitrate), (2) soil (calcium, magnesium, and potassium), and (3) salt (sodium, chloride, and ammonium). Concentrations of acid solutes in the snowpack are similar to concentrations in nearby wetfall collectors, whereas, concentrations of soil solutes are much higher in the snowpack than in wetfall. Thus, dryfall of acid solutes during the snow season is negligible, as is gypsum from soils. Snowpack sampling offers a cost-effective complement to sampling of wetfall in areas where wetfall is difficult to sample and where the snowpack accumulates throughout the winter. Copyright ?? 2001 .

Atmospheric Environment↗
USGS2000

Effects of the flood of 1993 on the chemical characteristics of bed sediments in the Upper Mississippi River

Concentrations of pollutants stored in the surficial bed sediments in the navigation pools of the Upper Mississippi River showed a general decrease after the record flood of 1993. Percent clay and total organic carbon in the surficial sediments decreased as a result of an increase in the proportion of coarser sediment. Decreases in pollutant concentration may have been a result of the dilution by coarser and relatively less polluted sediment that was mobilized and transported into the Upper Mississippi River from its tributaries or from mainstem locations upstream but outside of the sampling area.

Water, Air, & Soil Pollution↗
USGS2000

Metal exposure in a benthic macroinvertebrate, Hydropsyche californica, related to mine drainage in the Sacramento River

A biomonitoring technique was employed to complement studies of metal transport in the upper Sacramento River affected by acid mine drainage. Metals (Al, Cd, Cu, Fe, Hg, Pb, and Zn) were determined in a resident invertebrate, Hydropsyche californica (Insecta: Trichoptera), and streambed sediments (<62 µm) to assess metal contamination within a 111-km section of the river downstream of the mining area. Metals in H. californica also were interpreted to be broadly indicative of metal exposure in fish. Total Hg was determined in the whole body of the insect, whereas Al, Cd, Cu, Fe, Pb, and Zn were additionally separated into operationally defined cytosolic (used as an indicator of exposure to bioavailable metal) and particulate fractions. Total concentrations of Cd, Cu, Hg, Pb, and Zn in sediments were consistent with documented upstream sources of acid mine drainage. Metal distribution patterns in H. californica and sediments were generally consistent for Cd, Cu, and Pb but inconsistent for Hg and Zn. Concentrations in H. californica indicated that bioavailable Cd, Cu, Pb, and Zn was transported at least 120 km downstream of the mine sources. Zinc in H. californica was elevated, but unlike sediments, did not decrease downstream. Mercury in H. californica was not elevated.

California↗
USGS2000

Metals transport in the Sacramento River, California, 1996-1997; volume 1: Methods and data

Metals transport in the Sacramento River, northern California, was evaluated on the basis of samples of water, suspended colloids, streambed sediment, and caddisfly larvae that were collected on one to six occasions at 19 sites in the Sacramento River Basin from July 1996 to June 1997. Four of the sampling periods (July, September, and November 1996; and May-June 1997) took place during relatively low-flow conditions and two sampling periods (December 1996 and January 1997) took place during high-flow and flooding conditions; respectively. Tangential-flow ultrafiltration with 10,000 nominal molecular weight limit, or daltons (0.005 micrometer equivalent), pore-size membranes was used to separate metals in streamwater into ultrafiltrate (operationally defined dissolved fraction) and retentate (colloidal fraction) components, respectively. Conventional filtration with capsule filters (0.45 micrometer pore-size) and membrane filters (0.40 micrometer pore-size) and total-recoverable analysis of unfiltered (whole-body) samples were done for comparison at all sites. Because the total-recoverable analysis involves an incomplete digestion of particulate matter, a more reliable measurement of whole-water concentrations is derived from the sum of the dissolved component that is based on the ultrafiltrate plus the suspended component that is based on a total digestion of colloid concentrates from the ultra-filtration retentate. Metals in caddisfly larvae were determined for whole-body samples and cytosol extracts, which are intercellular solutions that provide a more sensitive indication of the metals that have been bioaccumulated. Trace metals in acidic, metal-rich drainage from abandoned and inactive sulfide mines were observed to enter the Sacramento River system (specifically, into both Shasta Lake and Keswick Reservoir) in predominantly dissolved form, as operationally defined using ultrafiltrates. The predominant source of acid mine drainage to Keswick Reservoir is Spring Creek, which drains the Iron Mountain mine area. Copper concentrations in filtered samples from Spring Creek taken during December 1996, January 1997, and May 1997 ranged from 420 to 560 micrograms per liter. Below Keswick Dam, copper concentrations in conventionally filtered samples ranged from 0.5 micrograms per liter during September 1996 to 9.4 micrograms per liter during January 1997; the latter concentration exceeded the applicable water-quality standard. The proportion of trace metals that was dissolved (versus colloidal) in samples collected at Shasta and Keswick dams decreased in the order cadmium zinc > copper > aluminum iron lead mercury. At four sampling sites on the Sacramento River at various distances downstream of Keswick Dam (Bend Bridge, 71 kilometers; Colusa, 256 kilometers; Verona, 360 kilometers; and Freeport, 412 kilometers) concentrations of these seven metals were predominantly colloidal during both high- and low-flow conditions. Because copper compounds are used extensively as algaecides in rice farming, agricultural drainage at the Colusa Basin Drain was sampled in June 1997 during a period shortly after copper applications to newly planted rice fields. Copper concentrations ranged from 1.3 to 3.0 micrograms per liter in filtered samples and from 12 to 13 micrograms per liter in whole-water samples (total recoverable analysis). These results are consistent with earlier work by the U.S. Geological Survey indicating that copper in rice-field drainage likely represents a detectable, but relatively minor source of copper to the Sacramento River. Lead isotope data from suspended colloids and streambed sediments collected during October and November 1996 indicate that lead from acid mine drainage sources became a relatively minor component of the total lead at the site located 71 kilometers downstream of Keswick Dam and beyond. Cadmium, copper, and zinc concentrations in caddisfly larvae were elevated at several sites downstream of Keswick Dam, but concentrations of aluminum, iron, lead, and mercury were relatively low, especially in the cytosol extracts. Cadmium showed the highest degree of bioaccumulation in whole-body and cytosol analyses, relative to an unmineralized control site (Cottonwood Creek). Cadmium bioaccumulation persisted in samples collected as far as 118 kilometers downstream of Keswick Dam, consistent with transport in a form more bioavailable than lead.

California↗
USGS1999

Trees, chemistry, and prehistory in the American Southwest

At least 200 000 trees were used in the building construction in Chaco Canyon, New Mexico, from about (AD) 850-1150. A large portion of these construction timbers were transported 50 km or more and the harvesting location(s) is not known. We argue that a feasible method for determining the wood source areas is to chemically characterize the possible source areas using modern wood and then attempt to match the prehistoric timbers to the modern signatures. This paper establishes the feasibility of this method. ICP-AES was employed to obtain element concentration values for 29 elements, from 62 trees, on three bedrock types. We conclude that it is possible to isolate the variation due to lithology if one controls for wood type (bark, sapwood, heartwood). In addition, ICP-MS was used for the analysis of a small sample of ancient wood. Data from these determinations are presented and the results indicate that the elemental variation is consistent with the most current model of wood use practices in Chaco Canyon. The methods pioneered here should be broadly applicable for determining wood source areas.

Journal of Archaeological Science↗
USGS1999

Temporal variations in dissolved selenium in Lake Kinneret (Israel)

Selenium is an essential micronutrient for the growth of the dinoflagellate Peridinium gatunense that dominates the spring algal bloom in Lake Kinneret (LK). The relationship between the levels of dissolved selenium species and the occurance of algal blooms in this lake was studied. During algal blooms of P. gatunense in spring and of the blue-green Aphanizomenon ovalisporum in fall (in 1994) the concentration of epilimnetic dissolved organic Se (Se(org)) increased whereas that of selenite (SeIV) decreased, to levels below the limit of detection: 5 ng/l. The disappearance of SeIV during these blooms is attributed to algal uptake and it is suggested that the growth of both algae may have depended on Se(org) regeneration. A budget performed for selenate (SeVI) suggests that this species is also consumed by algae but to a lesser extent than SeIV (in 1994 ~40% of the epilimnetic load). During the stratification period the hypolimnion of Lake Kinneret becomes anoxic, with high levels of dissolved sulfide. The affects of this environment on the distribution of Se oxy-anions, selenite (SeIV) and selenate(SeVI), were also studied. At the onset of thermal stratification (March) about 35% of the lake inventory of both Se oxidized species are entrapped in the hypolimnion. During stages of oxygen depletion and H2S accumulation, SeIV is completely and SeVI partially removed from this layer. The removal is attributed to reduction followed by formation of particulate reduced products, such as elemental selenium Se(o). The ratio between SeVI to total dissolved selenium (SE(T)) in water sources to the lake is ~0.84, about twice the corresponding ratio in the lake (~0.44, during holomixis). In the lake about 75% of annual SeVI inflow from external sources undergoes reduction to selenide (Se-II) and Se(o) through epilimnetic algal assimilation and hypolimnetic anoxic reduction, respectively. It is suggested that the latter oxidation of the dissolved organic selenide released from biogenic particles and of Se(o) only to the tetravalent species is the cause for the lower ratio of SeVI/Se(T) in the lake.

Aquatic Sciences↗
USGS1998

Considerations in As analysis and speciation

This article summarizes recent experiences in arsenic (As) quantification, preservation, and speciation developed during AWWA Research Foundation (AWWARF) and Water Industry Technical Action Fund (WITAF) projects. The goal of this article is to alert analysts and decision-makers to potential problems in As analysis and speciation, because there appear to be several unresolved problems with routine analytical approaches. In true split drinking water samples As was quantified by three accepted analytical methods in three laboratories. The techniques used were graphite furnace atomic absorption spectrometry (GFAAS), inductively coupled plasma mass spectrometry (ICP-MS), and hydride generation inductively coupled plasma-emission spectrometry (HG-ICP-AES). Experimental findings are organized into sections on As analysis, particulate As in water supplies, and examination of As speciation methods.

Journal of the American Water Works Association↗
USGS1998

Re-evaluation and extension of the scope of elements in US Geological Survey Standard Reference Water Samples

More than 100 US Geological Survey (USGS) Standard Reference Water Samples (SRWSs) were analyzed for numerous trace constituents, including Al, As, B, Ba, Be, Bi, Br, Cd, Cr, Co, Cu, I, Fe, Pb, Li, Mn, Mo, Ni, Rb, Sb, Se, Sr, Te, Tl, U, V, Zn and major elements (Ca, Mg, Na, SiO2, SO4, Cl) by inductively coupled plasma mass spectrometry and inductively coupled plasma atomic emission spectrometry. In addition, 15 USGS SRWSs and National Institute of Standards and Technology (NIST) standard reference material (SRM) 1641b were analyzed for mercury using cold vapor atomic fluorescence spectrometry. Also USGS SRWS Hg-7 was analyzed using isotope dilution-inductively coupled plasma mass spectrometry. The results were compared with the reported certified values of the following standard reference materials: NIST SRM 1643a, 1643b, 1643c and 1643d and National Research Council of Canada Riverine Water Reference Materials for Trace Metals SLRS-1, SLRS-2 and SLRS-3. New concentration values for trace and major elements in the SRWSs, traceable to the certified standards, are reported. Additional concentration values are reported for elements that were neither previously published for the SRWSs nor traceable to the certified reference materials. Robust statistical procedures were used that were insensitive to outliers. These data can be used for quality assurance/quality control purposes in analytical laboratories.

Analyst↗
USGS1996

Little Ice Age evidence from a south-central North American ice core, U.S.A.

In the past, ice-core records from mid-latitude glaciers in alpine areas of the continental United States were considered to be poor candidates for paleoclimate records because of the influence of meltwater on isotopic stratigraphy. To evaluate the existence of reliable paleoclimatic records, a 160-m ice core, containing about 250 yr of record was obtained from Upper Fremont Glacier, at an altitude of 4000 m in the Wind River Range of south-central North America. The δ 18 O (SMOW) profile from the core shows a -0.95‰ shift to lighter values in the interval from 101.8 to 150 m below the surface, corresponding to the latter part of the Little Ice Age (LIA). Numerous high-amplitude oscillations in the section of the core from 101.8 to 150 m cannot be explained by site-specific lateral variability and probably reflect increased seasonality or better preservation of annual signals as a result of prolonged cooler temperatures that existed in this alpine setting. An abrupt decrease in these large amplitude oscillations at the 101.8-m depth suggests a sudden termination of this period of lower temperatures which generally coincides with the termination of the LIA. Three common features in the δ18O profiles between Upper Fremont Glacier and the better dated Quelccaya Ice Cap cores indicate a global paleoclimate linkage, further supporting the first documented occurrence of the LIA in an ice-core record from a temperate glacier in south-central North America.

Upper Fremont Glacier, Wind River Range↗
USGS1996

Automated, colorimetric methods for determination of nitrate plus nitrite, nitrite, ammonium and orthophosphate ions in natural water samples

The apparatus and methods used for the automatic, colorimetric determinations of dissolved nutrients (nitrate plus nitrite, nitrite, ammonium and orthophosphate) in natural waters are described. These techniques allow for the determination of nitrate plus nitrite for the concentration range 0.02 to 8 mg/L (milligrams per liter) as N (nitrogen); for nitrite, the range is 0.002 to 1.0 mg/L as N; for ammonium, the range is 0.006 to 2.0 mg/L as N; and for orthophosphate, the range is 0.002 to 1.0 mg/L as P (phosphorus). Data are presented that demonstrate the accuracy, precision and quality control of the methods.

Open-File Report↗
USGS1996

Inductively coupled plasma-mass spectrometric method for the determination of dissolved trace elements in natural water

An inductively coupled plasma-mass spectrometry method was developed for the determination of dissolved Al, As, B, Ba, Be, Cd, Co, Cr, Cu, Li, Mn, Mo, Ni, Pb, Sr, Tl, U, V, and Zn in natural waters. Detection limits are generally in the 50-100 picogram per milliliter (pg/mL) range, with the exception of As which is in the 1 microgram per liter (ug/L) range. Interferences associated with spectral overlap from concomitant isotopes or molecular ions and sample matrix composition have been identified. Procedures for interference correction and reduction related to isotope selection, instrumental operating conditions, and mathematical data processing techniques are described. Internal standards are used to minimize instrumental drift. The average analytical precision attainable for 5 times the detection limit is about 16 percent. The accuracy of the method was tested using a series of U.S. Geological Survey Standard Reference Water Standards (SWRS), National Research Council Canada Riverine Water Standard, and National Institute of Standards and Technology (NIST) Trace Elements in Water Standards. Average accuracies range from 90 to 110 percent of the published mean values.

Open-File Report↗
USGS1996

Method for the determination of dissolved chloride, nitrate, and sulfate in natural water using ion chromatography

Ion chromatography was used for the determination of dissolved chloride, nitrate and sulfate in natural water where concentrations ranged from a detection limit of 0.02 milligrams per liter to 80 milligrams per liter for chloride, to 18 milligrams per liter for nitrate, and to 280 milligrams per liter for sulfate. Specific conductance was the mode of detection used. Three analytical sample size loops of 11, 61, and 250 microliters, were used to include the analytical ranges described. U.S. Geological Survey Standard Reference Water Samples were analyzed to test the precision and accuracy of the analyses.

Open-File Report↗
USGS1996

Concentrations and loads of selected trace elements and other constituents in the Rio Grande in the vicinity of Albuquerque, New Mexico, 1994

The Pueblo of Isleta and the New Mexico Environment Department have established water-quality standards for the Rio Grande, which flows through Albuquerque, New Mexico. Trace-element concentrations historically have been greater than maximum permissible concentrations allowed by these standards. It is not known if these concentrations are due to sources from the Albuquerque metropolitan area or are from natural or other sources outside Albuquerque. Accurate water-quality data with lower reporting limits than have been previously available were collected, and instantaneous concentrations and loads were calculated for trace elements and other constituents in the Rio Grande during high-flow and low- flow conditions. Seven sampling sites were selected upstream from, in, and downstream from metropolitan Albuquerque. Concurrent streamflow measurements were made at the time of sampling to determine suspended-sediment loads. Samples were analyzed separately for trace elements dissolved in water (less than 0.4 micrometer in diameter) and for those contained in suspended sediment (greater than 0.1 micrometer in diameter). Sample collection and processing, analytical methods, and quality control are discussed.

New Mexico↗