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B.F. Jones

Publications and source records attributed to B.F. Jones.

At least 19 recordsLinked to original sources
USGS2024

Comparison of rapid methods for chemical analysis of milligram samples of ultrafine clays

Two rapid methods for the decomposition and chemical analysis of clays were adapted for use with 20–40-mg size samples, typical amounts of ultrafine products (≤0.5-µm diameter) obtained by modern separation methods for clay minerals. The results of these methods were compared with those of “classical” rock analyses. The two methods consisted of mixed lithium metaborate fusion and heated decomposition with HF in a closed vessel. The latter technique was modified to include subsequent evaporation with concentrated H 2 SO 4 and re-solution in HCl, which reduced the interference of the fluoride ion in the determination of Al, Fe, Ca, Mg, Na, and K. Results from the two methods agree sufficiently well with those of the “classical” techniques to minimize error in the calculation of clay mineral structural formulae. Representative maximum variations, in atoms per unit formula of the smectite type based on 22 negative charges, are 0.09 for Si, 0.03 for Al, 0.015 for Fe, 0.07 for Mg, 0.03 for Na, and 0.01 for K.

Clays and Clay Minerals↗
USGS2018

Geochemical investigation of weathering processes in a forested headwater catchment: Mass-balance weathering fluxes

Geochemical research on natural weathering has often been directed towards explanations of the chemical composition of surface water and ground water resulting from subsurface water-rock interactions. These interactions are often defined as the incongruent dissolution of primary silicates, such as feldspar, producing secondary weathering products, such as clay minerals and oxyhydroxides, and solute fluxes (Meunier and Velde, 1979). The chemical composition of the clay-mineral product is often ignored. However, in earlier investigations, the saprolitic weathering profile at the South Fork Brokenback Run (SFBR) watershed, Shenandoah National Park, Virginia, was characterized extensively in terms of its mineralogical and chemical composition (Piccoli, 1987; Pochatila et al., 2006; Jones et al., 2007) and its basic hydrology. O'Brien et al. (1997) attempted to determine the contribution of primary mineral weathering to observed stream chemistry at SFBR. Mass-balance model results, however, could provide only a rough estimate of the weathering reactions because idealized mineral compositions were utilized in the calculations. Making use of detailed information on the mineral occurrence in the regolith, the objective of the present study was to evaluate the effects of compositional variation on mineral-solute mass-balance modelling and to generate plausible quantitative weathering reactions that support both the chemical evolution of the surface water and ground water in the catchment, as well as the mineralogical evolution of the weathering profile. ?? 2008 The Mineralogical Society.

Conference Paper↗
USGS2011

An equation of state for hypersaline water in Great Salt Lake, Utah, USA

Great Salt Lake (GSL) is one of the largest and most saline lakes in the world. In order to accurately model limnological processes in GSL, hydrodynamic calculations require the precise estimation of water density ( ρ ) under a variety of environmental conditions. An equation of state was developed with water samples collected from GSL to estimate density as a function of salinity and water temperature. The ρ of water samples from the south arm of GSL was measured as a function of temperature ranging from 278 to 323 degrees Kelvin ( o K) and conductivity salinities ranging from 23 to 182 g L −1 using an Anton Paar density meter. These results have been used to develop the following equation of state for GSL (σ = ± 0.32 kg m −3 ): ρ − ρ 0 = 184 .0 10 6 2 + 1 .0 4 70 8 ∗ S − 1. 2 10 6 1 ∗ T + 3 . 1 4 7 2 1 E − 4 ∗ S 2 + 0.00 1 9 9 T 2 − 0.00 1 1 2 ∗ S ∗ T , where ρ 0 is the density of pure water in kg m −3 , S is conductivity salinity g L −1 , and T is water temperature in degrees Kelvin.

Utah↗
USGS2009

Pore-water chemistry from the ICDP-USGS coer hole in the Chesapeake Bay impact structure--Implications for paleohydrology, microbial habitat, and water resources

We investigated the groundwater system of the Chesapeake Bay impact structure by analyzing the pore-water chemistry in cores taken from a 1766-m-deep drill hole 10 km north of Cape Charles, Virginia. Pore water was extracted using high-speed centrifuges from over 100 cores sampled from a 1300 m section of the drill hole. The pore-water samples were analyzed for major cations and anions, stable isotopes of water and sulfate, dissolved and total carbon, and bioavailable iron. The results reveal a broad transition between fresh and saline water from 100 to 500 m depth in the post-impact sediment section, and an underlying syn-impact section that is almost entirely filled with brine. The presence of brine in the lowermost post-impact section and the trend in the dissolved chloride with depth suggest a transport process dominated by molecular diffusion and slow, compaction-driven, upward flow. Major ion results indicate residual effects of diagenesis from heating, and a pre-impact origin for the brine. High levels of dissolved organic carbon (6-95 mg/L) and the distribution of electron acceptors indicate an environment that may be favorable for microbial activity throughout the drilled section. The concentration and extent of the brine is much greater than had previously been observed, suggesting its occurrence may be common in the inner crater. However, groundwater flow conditions in the structure may reduce the salt-water-intrusion hazard associated with the brine.

Special Paper of the Geological Society of America↗
USGS2007

Evidence that the ZNT3 protein controls the total amount of elemental zinc in synaptic vesicles

The ZNT3 protein decorates the presynaptic vesicles of central neurons harboring vesicular zinc, and deletion of this protein removes staining for zinc. However, it has been unclear whether only histochemically reactive zinc is lacking or if, indeed, total elemental zinc is missing from neurons lacking the Slc30a3 gene, which encodes the ZNT3 protein. The limitations of conventional histochemical procedures have contributed to this enigma. However, a novel technique, microprobe synchrotron X-ray fluorescence, reveals that the normal 2- to 3-fold elevation of zinc concentration normally present in the hippocampal mossy fibers is absent in Slc30a3 knockout (ZNT3) mice. Thus, the ZNT3 protein evidently controls not only the "stainability" but also the actual mass of zinc in mossy-fiber synaptic vesicles. This work thus confirms the metal-transporting role of the ZNT3 protein in the brain. ?? The Histochemical Society, Inc.

Journal of Histochemistry and Cytochemistry↗
USGS2006

Effects of enhanced zinc and copper in drinking water on spatial memory and fear conditioning

Ingestion of enhanced zinc can cause memory impairments and copper deficiencies. This study examined the effect of zinc supplementation, with and without copper, on two types of memory. Rats raised pre- and post-natally on 10 mg/kg ZnCO3 or ZnSO4 in the drinking water were tested in a fear-conditioning experiment at 11 months of age. Both zinc groups showed a maladaptive retention of fearful memories compared to controls raised on tap water. Rats raised on 10 mg/kg ZnCO3, 10 mg/kg ZnCO3 + 0.25 mg/kg CuCl2, or tap water, were tested for spatial memory ability at 3 months of age. Significant improvements in performance were found in the ZnCO3 + CuCl2 group compared to the ZnCO3 group, suggesting that some of the cognitive deficits associated with zinc supplementation may be remediated by addition of copper. ?? 2005 Elsevier B.V. All rights reserved.

Journal of Geochemical Exploration↗
USGS2005

Enhanced zinc consumption causes memory deficits and increased brain levels of zinc

Zinc deficiency has been shown to impair cognitive functioning, but little work has been done on the effects of elevated zinc. This research examined the effect on memory of raising Sprague–Dawley rats on enhanced levels of zinc (10 ppm ZnCO 3 ; 0.153 mM) in the drinking water for periods of 3 or 9 months, both pre- and postnatally. Controls were raised on lab water. Memory was tested in a series of Morris Water Maze (MWM) experiments, and zinc-treated rats were found to have impairments in both reference and working memory. They were significantly slower to find a stationary platform and showed greater thigmotaxicity, a measure of anxiety. On a working memory task, where the platform was moved each day, zinc-treated animals had longer latencies over both trials and days, swam further from the platform, and showed greater thigmotaxicity. On trials using an Atlantis platform, which remained in one place but was lowered on probe trials, the zinc-treated animals had significantly fewer platform crossings, spent less time in the target quadrant, and did not swim as close to the platform position. They had significantly greater latency on nonprobe trials. Microprobe synchrotron X-ray fluorescence (μSXRF) confirmed that brain zinc levels were increased by adding ZnCO 3 to the drinking water. These data show that long-term dietary administration of zinc can lead to impairments in cognitive function.

Physiology & Behavior↗
USGS2001

Petrographic and geochemical evidence for the formation of primary, bacterially induced lacustrine dolomite: La Roda 'white earth' (Pliocene, Central Spain)

Upper Pliocene dolomites ('white earth') from La Roda, Spain, offer a good opportunity to evaluate the process of dolomite formation in lakes. The relatively young nature of the deposits could allow a link between dolomites precipitated in modern lake systems and those present in older lacustrine formations. The La Roda Mg-carbonates (dolomite unit) occur as a 3??5- to 4-m- thick package of poorly indurated, white, massive dolomite beds with interbedded thin deposits of porous carbonate displaying root and desiccation traces as well as local lenticular gypsum moulds. The massive dolomite beds consist mainly of loosely packed 1- to 2-??m-sized aggregates of dolomite crystals exhibiting poorly developed faces, which usually results in a subrounded morphology of the crystals. Minute rhombs of dolomite are sparse within the aggregates. Both knobbly textures and clumps of spherical bodies covering the crystal surfaces indicate that bacteria were involved in the formation of the dolomites. In addition, aggregates of euhedral dolomite crystals are usually present in some more clayey (sepiolite) interbeds. The thin porous carbonate (mostly dolomite) beds exhibit both euhedral and subrounded, bacterially induced dolomite crystals. The carbonate is mainly Ca-dolomite (51-54 mol% CaCO3), showing a low degree of ordering (degree of ordering ranges from 0??27 to 0??48). Calcite is present as a subordinate mineral in some samples. Sr, Mn and Fe contents show very low correlation coefficients with Mg/Ca ratios, whereas SiO2 and K contents are highly correlated. ??18O- and ??13C-values in dolomites range from -3??07??? to 5??40??? PDB (mean = 0??06, ?? = 1??75) and from -6??34??? to -0??39??? PDB (mean = -3??55, ?? = 1??33) respectively. Samples containing significant amounts of both dolomite and calcite do not in general show significant enrichment or depletion in 18O and 13C between the two minerals. The correlation coefficient between ??18O and ??13C for dolomite is extremely low and negative (r = -0??05), whereas it is higher and positive (r = 0??47) for calcite. The lacustrine dolomite deposit from La Roda is interpreted mainly as a result of primary precipitation of dolomite in a shallow, hydrologically closed perennial lake. The lake was supplied by highly saturated HCO3-/CO32- groundwater that leached dolomitic Mesozoic formations. Precipitation of dolomite from alkaline lake waters took place under a semi-arid to arid climate. However, according to our isotopic data, strong evaporative conditions were not required for the formation of the La Roda dolomite. A significant contribution by bacteria to the formation of the dolomites is assumed in view of both petrographic and geochemical evidence.

Sedimentology↗
USGS1998

The chemical evolution of Kurnub Group palcowater in the Sinai-Negev province - A mass balance approach

The chemical evolution of the Kurnub Group paleowater was studied starting from rainwater in recharge areas of the Sinai and along groundwater flowpaths leading to the natural outlets of this regional aquifer. This was achieved by investigating the chemical composition of groundwater, ionic ratios, degrees of saturation with common mineral species, normative analysis of dissolved salts and by modeling of rock/water interaction and mixing processes occurring along groundwater flow paths. The initial groundwater composition used is from the Nakhel well in Sinai. It evolves from desert rainwater percolating through typical Kurnub Group lithology in Sinai. This rainwater dissolves mainly gypsum, halite and dolomite together with smaller amounts of marine aerosol and K-feldspar. At the same time it precipitates calcite, SiO2, smectite and degasses CO2. Between the area of Nakhel and the northern Negev the chemistry of Kurnub Group waters is influenced by dissolution of halite and lesser amounts of gypsum of surficial origin in recharge areas, small amounts of feldspars and of dolomite cement in sandstones eroded from the Arabo-Nubian igneous massif of Sinai and organic degradation-derived CO2. Concomitantly, there is precipitation of calcite, smectite, SiO2 and probably analcime characteristic of sediments in continental closed basins. North of the Negev, the Kurnub Group fluids are diluted and altered by mixing with Judea Group aquifer groundwaters. On the E there is mixing with residual brines from the water body ancestral to the Dead Sea, prior to discharge into the Arava valley. Rock/water interaction indicated by NETPATH and PHREEQC modeling is in agreement with lithology and facies changes previously observed in the Kurnub Group sequence.

Applied Geochemistry↗
USGS1998

Lithological and hydrological influences on ground-water composition in a heterogeneous carbonate-clay aquifer system

The influence of clay units on ground-water composition was investigated in a heterogeneous carbonate aquifer system of Miocene age in southwest Florida, known as the Intermediate aquifer system. Regionally, the ground water is recharged inland, flows laterally and to greater depths in the aquifer systems, and is discharged vertically upward at the saltwater interface along the coast. A depth profile of water composition was obtained by sampling ground water from discrete intervals within the permeable carbonate units during coring and by squeezing pore water from a core of the less-permeable clay layers. A normative salt analysis of solute compositions in the water indicated a marine origin for both types of water and an evolutionary pathway for the clay water that involves clay diagenesis. The chemical composition of the ground water in the carbonate bedrock is significantly different from that of the pore water in the clay layers. Dissolution of clays and opaline silica results in high silica concentrations relative to water in other parts of the Intermediate aquifer system. Water enriched in chloride relative to the overlying and underlying ground water recharges the aquifer inland where the confining clay layer is absent, and it dissolves carbonate and silicate minerals and reacts with clays along its flow path, eventually reaching this coastal site and resulting in the high chloride and silica concentrations observed in the middle part of the Intermediate aquifer system. Reaction-path modeling suggests that the recharging surficial water mixes with sulfate-rich water upwelling from the Upper Floridan aquifer, and carbonate mineral dissolution and precipitation, weathering and exchange reactions, clay mineral diagenesis, clay and silica dissolution, organic carbon oxidation, and iron and sulfate reduction result in the observed water compositions.

Geological Society of America Bulletin↗
USGS1996

Waters associated with an active basaltic volcano, Kilauea, Hawaii: Variation in solute sources, 1973-1991

Chemical and isotopic analyses of samples collected from a December 1962-m-deep research borehole at the summit of Kilauea Volcano provide unique time-series data for composition of waters in the uppermost part of its hydrothermal system. These waters have a distinctive geochemical signature: a very low proportion of chloride relative to other anions compared with other Hawaiian waters—thermal (•30°C) or nonthermal (<30°C)—and with most thermal waters of the world. Isotope data demonstrate that the borehole waters are of essentially meteoric origin, with minimal magmatic input.

Hawaii↗
USGS1994

Sources of dissolved salts in the central Murray Basin, Australia

Large areas of the Australian continent contain scattered saline lakes underlain by shallow saline groundwaters of regional extent and debated origin. The normative salt composition of subsurface pore fluids extracted by squeezing cores collected during deep drilling at Piangil West 2 in the central Murray Basin in southeastern Australia, and of surface and shallow subsurface brines produced by subaerial evaporation in the nearby Lake Tyrrell systems, helps constrain interpretation of the origin of dissolved solutes in the groundwaters of this part of the continent. Although regional sedimentation in the Murray Basin has been dominantly continental except for a marine transgression in Oligocene-Pliocene time, most of the solutes in saline surface and subsurface waters in the central Murray Basin have a distinctly marine character. Some of the Tyrrell waters, to the southwest of Piangil West 2, show the increase in NaCl and decrease in sulfate salts expected with evaporative concentration and gypsum precipitation in an ephemeral saline lake or playa environment. The salt norms for most of the subsurface saline waters at Piangil West 2 are compatible with the dilution of variably fractionated marine bitterns slightly depleted in sodium salts, similar to the more evolved brines at Lake Tyrrell, which have recharged downward after evaporation at the surface and then dissolved a variable amount of gypsum at depth. Apparently over the last 0.5 Ma significant quantities of marine salt have been blown into the Murray Basin as aerosols which have subsequently been leached into shallow regional groundwater systems basin-wide, and have been transported laterally into areas of large evaporative loss in the central part of the basin. This origin for the solutes helps explain why the isotopic compositions of most of the subsurface saline waters at Piangil West 2 have a strong meteoric signature, whereas the dissolved salts in these waters appear similar to a marine assemblage. ?? 1994.

Chemical Geology↗
USGS1991

An aem-tem study of weathering and diagenesis, Abert Lake, Oregon: I. Weathering reactions in the volcanics

Abert Lake in south-central Oregon provides a site suitable for the study of sequential weathering and diagenetic events. In this first of two papers, transmission electron microscopy was used to characterize the igneous mineralogy, subsolidus alteration assemblage, and the structural and chemical aspects of silicate weathering reactions that occur in the volcanic rocks (basalts, basaltic andesites, and dacitic/ rhyolitic extrusive and pyroclastics) that outcrop around the lake. Olivine and pyroxene replacement occurred topotactically, whereas feldspar and glass alteration produced randomly oriented smectite in channels and cavities. The tetrahedral, octahedral, and interlayer compositions of the weathering products, largely dioctahedral smectites, varied with primary mineral composition, rock type, and as the result of addition of elements released from adjacent reaction sites. Weathering of the highly evolved, Fe-rich Jug Mountain complex at the north end of the lake produced a homogeneous smectite assemblage that contrasts with the heterogeneous smectite assemblage replacing the volcanics along the eastern margin of the lake. The variability within and between the smectite assemblages highlights the microenvironmental diversity, fluctuating redox conditions, and variable solution chemistry associated with mineral weathering reactions in the surficial environment. Late-stage exhalative and aqueous alteration of the volcanics redistributed many components and formed a variety of alkali and alkali-earth carbonate, chloride, sulfate, and fluoride minerals in vugs and cracks. Overall, substantial Mg, Si, Na, Ca, and K are released by weathering reactions that include the almost complete destruction of the Mg-smectite that initially replaced olivine. The leaching of these elements from the volcanics provides an important source of these constituents in the lake water. The nature of subsequent diagenetic reactions resulting from the interaction between the materials transported to the lake and the solution will be described in part II ( Banfield et al., 1991).

Geochimica et Cosmochimica Acta↗
USGS1991

An AEM-TEM study of weathering and diagenesis, Abert Lake, Oregon: II. Diagenetic modification of the sedimentary assemblage

This paper compares the mineralogy and chemistry of clay minerals in sediments from various depths and positions in Abert Lake and surrounding playa with those of the weathered materials entering the lake in order to reveal the nature and extent of post-depositional mineralogical modification. Analytical electron microscope (AEM) data from individual clay particles reveal that each sample is comprised of a highly inhomogeneous smectite assemblage. The thin clay flakes (commonly less than 10 nm wide) display a complete range in octahedral sheet compositions from nearly dioctahedral to nearly trioctahedral. The very abundant Mg-rich lake smectites with an estimated composition K 0.29 (Al 0.23 -Mg 2.16 Fe 0.30 )Si 3.80 Al 0.20 O 10 (OH) 2 are not formed by weathering. This confirms the importance of diagenetic Mg uptake. Lattice-fringe imaging failed to reveal distinct brucite-like or vermiculite-like layers, suggesting that interstratifications of this type are rare or absent. Siliceous coatings on clay particles (identified by silica excess in smectite analyses) seem to favor topotactic overgrowth of stevensite rather than addition of brucite-like layers to the dioctahedral nuclei. The growth of K-stevensite dilutes the Al content of the crystal, and thus the increasing diagenetic modification reduces rather than supplements its illite component. Smectite compositions within individual samples were highly variable, yet source-related characteristics such as the abundance of Fe-rich smectite were apparent. Little evidence for systematic K or Mg enrichment with depth was identified in samples from depths of down to 16 feet below the sediment-water interface. The most magnesian assemblages are associated both with weathering sources of Mg-rich smectite and playa environments subjected to repeated wetting and drying cycles. Thus, the observations suggest that clay compositions primarily reflect changes in lake levels, brine composition, and source characteristics, rather than time and depth/compaction effects. Other diagenetic reactions in the sediment include recrystallization of Na-rich silica gel and diatom fragments. Abundant, submicron-sized, untwinned, euhedral crystals of K-feldspar are interpreted to be authigenic in origin.

Geochimica et Cosmochimica Acta↗
USGS1990

Transmission electron microscopy of subsolidus oxidation and weathering of olivine

Olivine crystals in basaltic andesites which crop out in the Abert Rim, south-central Oregon have been studied by high-resolution and analytical transmission electron microscopy. The observations reveal three distinct assemblages of alteration products that seem to correspond to three episodes of olivine oxidation. The olivine crystals contain rare, dense arrays of coherently intergrown Ti-free magnetite and inclusions of a phase inferred to be amorphous silica. We interpret this first assemblage to be the product of an early subsolidus oxidation event in the lava. The second olivine alteration assemblage contains complex ordered intergrowths on (001) of forsterite-rich olivine and laihunite (distorted olivine structure with Fe3+ charge balanced by vacancies). Based on experimental results for laihunite synthesis (Kondoh et al. 1985), these intergrowths probably formed by olivine oxidation between 400 and 800??C. The third episode of alteration involves the destruction of olivine by low-temperature hydrothermal alteration and weathering. Elongate etch-pits and channels in the margins of fresh olivine crystals contain semi-oriented bands of smectite. Olivine weathers to smectite and hematite, and subsequently to arrays of oriented hematite crystals. The textures resemble those reported by Eggleton (1984) and Smith et al. (1987). We find no evidence for a metastable phase intermediate between olivine and smectite ("M" - Eggleton 1984). The presence of laihunite exerts a strong control on the geometry of olivine weathering. Single laihunite layers and laihunite-forsteritic olivine intergrowths increase the resistance of crystals to weathering. Preferential development of channels between laihunite layers occurs where growth of laihunite produced compositional variations in olivine, rather than where coherency-strain is associated with laihunite-olivine interfaces. ?? 1990 Springer-Verlag.

Contributions to Mineralogy and Petrology↗