Book reviews     

Philip Rasch  L. D. Danny Harvey  R. G. Barry 《Climatic change》1987,10(2):201-206

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Rates of sulfur dioxide and particle emissions from White Island volcano,New Zealand,and an estimate of the total flux of major gaseous species     

William I. Rose  Raymond L. Chuan  Werner F. Giggenbach  Philip R. Kyle  Robert B. Symonds 《Bulletin of Volcanology》1986,48(4):181-188

Airborne correlation spectrometry (COSPEC) was used to measure the rate of SO₂ emission at White Island on three dates, i.e., November 1983, 1230 ± 300 t/d; November 1984, 320 ± 120 t/d; and January 1985, 350 ± 150 t/d (t = metric tons). The lower emission rates are likely to reflect the long-term emission rates, whereas the November 1983 rate probably reflects conditions prior to the eruption of December 1983. The particle flux in the White Island plume, as determined with a quartz crystal microbalance/cascade in November 1983, was 1.3 t/d, unusually low for volcanic plumes. The observed plume particles, as shown from scanning electron microscopy, include halite, native sulfur, and silicates and are broadly similar to other volcanic plumes.Gas analyses from high-temperature volcanic fumaroles collected from June 1982 through November 1984 werde used together with the COSPEC data to estimate the flux of other gas species from White Island. The rates estimated are indicative of the long-term volcanic emission, i.e., 8000–9000 t/d H₂O, 900–1000 t/d CO₂, 70–80 t/d HCl, 1.5–2 t/d HF, and about 0.2 t/d NH₃. The long-term thermal power output at White Island is estimated at about 400 MW.  相似文献   

A petrographic and fluid inclusion comparison of silver-poor and silver-rich zinc-lead ores,N.E. Washington State     

Philip E. Brown  Gaafar A. Ahmed 《Mineralium Deposita》1986,21(2):156-163

Many of the zinc-lead deposits of NE Washington State are poorly known examples of Mississippi Valley Type (MVT) mineralization. This study compares inclusion fluids from the Josephine Breccia ores with the later cross-cutting sulfide-bearing quartz veins. The breccia ores are cemented mainly by open space fillings of dolomite, sphalerite, quartz, galena, jasperoid and calcite. Replacement is of minor importance. Ore and gangue deposition occurred over the range 150–250 °C with most of the temperatures less than 200 °C. The aqueous brines typically contain 17–23 equivalent weight percent NaCl with often substantial amounts of Ca and/or Mg chlorides. Homogenization temperatures do not delineate any cooling or paragenetic sequence. The cross-cutting vein quartz contains CO₂-rich inclusions with overall densities usually less than 0.7 g/cc and homogenization temperatures from 250–325 °C. Sulfur isotope analyses yield two populations with the quartz vein ores being lighter (<13 permil CDT) than the average for the conformable ores. The later veins are not remobilized MVT sulfides but represent a separate, high-silver period of mineralization.  相似文献   

Catastrophic subsidence: An environmental hazard,shelby county,Alabama     

Philip E. Lamoreaux  J. G. Newton 《Environmental Geology》1986,8(1-2):25-40

Induced sinkholes (catastrophic subsidence) are those caused or accelerated by human activities These sinkholes commonly result from a water level decline due to pumpage Construction activities in a cone of depression greatly increases the likelihood of sinkhole occurrence Almost all occur where cavities develop in unconsolidated deposits overlying solution openings in carbonate rocks. Triggering mechanisms resulting from water level declines are (1) loss of buoyant support of the water, (2) increased gradient and water velocity, (3) water-level fluctuations, and (4) induced recharge Construction activities triggering sinkhole development include ditching, removing overburden, drilling, movement of heavy equipment, blasting and the diversion and impoundment of drainage Triggering mechanisms include piping, saturation, and loading Induced sinkholes resulting from human water development/management activities are most predictable in a youthful karst area impacted by groundwater withdrawals Shape, depth, and timing of catastrophic subsidence can be predicted in general terms Remote sensing techniques are used in prediction of locations of catastrophic subsidence. This provides a basis for design and relocation of structures such as a gas pipeline, dam, or building Utilization of techniques and a case history of the relocation of a pipeline are described  相似文献   

Towards the detection and attribution of an anthropogenic effect on climate   总被引：1，自引：0，他引：1  

Benjamin D. Santer  Karl E. Taylor  Tom M. L. Wigley  Joyce E. Penner  Philip D. Jones  Ulrich Cubasch 《Climate Dynamics》1995,12(2):77-100

It has been hypothesized recently that regional-scale cooling caused by anthropogenic sulfate aerosols may be partially obscuring a warming signal associated with changes in greenhouse gas concentrations. Here we use results from model experiments in which sulfate and carbon dioxide have been varied individually and in combination in order to test this hypothesis. We use centered [R (t)] and uncentered [C (t)] pattern similarity statistics to compare observed time-evolving surface temperature change patterns with the model-predicted equilibrium signal patterns. We show that in most cases, the C (t) statistic reduces to a measure of observed global-mean temperature changes, and is of limited use in attributing observed climate changes to a specific causal mechanism. We therefore focus on R (t), which is a more useful statistic for discriminating between forcing mechanisms with different pattern signatures but similar rates of global mean change. Our results indicate that over the last 50 years, the summer (JJA) and fall (SON) observed patterns of near-surface temperature change show increasing similarity to the model-simulated response to combined sulfate aerosol/CO₂ forcing. At least some of this increasing spatial congruence occurs in areas where the real world has cooled. To assess the significance of the most recent trends in R (t) and C (t), we use data from multi-century control integrations performed with two different coupled atmosphere-ocean models, which provide information on the statistical behavior of 'unforced' trends in the pattern correlation statistics. For the combined sulfate aerosol/CO₂ experiment, the 50-year R (t) trends for the JJA and SON signals are highly significant. Results are robust in that they do not depend on the choice of control run used to estimate natural variability noise properties. The R (t) trends for the CO₂-only signal are not significant in any season. C (t) trends for signals from both the CO₂-only and combined forcing experiments are highly significant in all seasons and for all trend lengths (except for trends over the last 10 years), indicating large global-mean changes relative to the two natural variability estimates used here. The caveats regarding the signals and natural variability noise which form the basis of this study are numerous. Nevertheless, we have provided first evidence that both the largest-scale (global-mean) and smaller-scale (spatial anomalies about the global mean) components of a combined CO₂/anthropogenic sulfate aerosol signal are identifiable in the observed near-surface air temperature data. If the coupled-model noise estimates used here are realistic, we can be highly confident that the anthropogenic signal that we have identified is distinctly different from internally generated natural variability noise. The fact that we have been able to detect the detailed spatial signature in response to combined CO₂ and sulfate aerosol forcing, but not in response to CO₂ forcing alone, suggests that some of the regional-scale background noise (against which we were trying to detect a CO₂-only signal) is in fact part of the signal of a sulfate aerosol effect on climate. The large effect of sulfate aerosols found in this study demonstrates the importance of their inclusion in experiments designed to simulate past and future climate change. Received: 10 November 1994 / Accepted: 19 July 1995  相似文献   

The uptake of dissolved zinc and cadmium by the decapod crustacean Palaemon elegans     

Dayanthi Nugegoda  Philip S. Rainbow 《Marine pollution bulletin》1995,31(4-12):460-463

The rates of uptake of the heavy metals zinc and cadmium from solution were measured in the caridean decapod crustacean Palaemon elegans. When radioactively-labelled zinc and cadmium were present together with both at dissolved concentrations of 20 μg l⁻¹, the rate of zinc uptake by the decapod decreased and the rate of cadmium uptake increased in comparison with the uptake rates of each metal in single metal exposures of 20 μg l⁻¹. This effect can be interpreted as a result of competition between the two metals for uptake routes. The rate of zinc uptake by individual P. elegans is positively linearly correlated with the rate of cadmium uptake. Thus, some individuals have inherently higher metal uptake rates than others, although such uptake rates are also greatly affected by the stage in the moult cycle.  相似文献   

Simulations of Flow in Crystalline Rock and Recharge from Overlying Glacial Deposits in a Hypothetical New England Setting   总被引：1，自引：0，他引：1  

Philip T. Harte  Thomas C. Winter 《Ground water》1995,33(6):953-964

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Some Biases in Sampling Multilevel Piezometers for Volatile Organics     

J. F. Barker  G. C Patrick  L. Lemon  G. M. Travis 《Ground Water Monitoring & Remediation》1987,7(2):48-54

Multilevel piezometers are cost-effective monitoring devices for determining the three-dimensional distribution of solutes in ground water. Construction includes flexible tubing (plastic or Teflon®). Their sampling is subject to a number of'potential biases, particularly: (1) losses of volatile organic solutes via volatilization, (2) sorption onto the flexible tubing of the piezometers, (3) leaching of organics from this tubing, and (4) collection of unrepresentative samples due to inadequate piezometer flushing. It is shown that these biases are minimal or are easily controlled in most situations.
Another source of bias has been recognized. Organic solutes present in ground water above the screened level can penetrate the flexible plastic or Teflon tubing and contaminate the sampled water being drawn through this tubing. Laboratory tests and field results indicate this transmission causes low organic contaminant concentrations to be erroneously attributed to ground water which is free of such contaminants. The transmitted organics apparently desorb from the plastic tubing during flushing of even 40 piezometer volumes.
Recognition of this transmission problem provides for a better interpretation of existing organic contaminant distribution data. Caution is advised when considering the use of these monitoring devices in organic solute contaminant studies.  相似文献   

Rhyolites contaminated with metapelite and gabbro,Lipari, Aeolian Islands,Italy: products of lower crustal fusion or of assimilation plus fractional crystallization?     

Daniel S. Barker 《Contributions to Mineralogy and Petrology》1987,97(4):460-472

Pleistocene lavas from Monte S. Angelo and Chiesa Vecchia volcanoes on Lipari contain two suites of inclusions. A metapelitic suite consists of gneisses and granulites with combinations of cordierite, garnet, corundum, hercynite, andalusite, sillimanite, orthopyroxene, ilmenite, magnetite, biotite, plagioclase, and quartz. A gabbroic suite has cumulus texture and contains plagioclase, orthopyroxene, clinopyroxene, and magnetite. All megacryst phases in the lavas appear to be derived from rock fragments, with the exception of euhedral strongly zoned calcic plagioclase, and none has grown by homogeneous nucleation from liquid represented by the groundmass, which is peraluminous rhyolite (>70 wt% SiO₂, >6 wt% K₂O). Ground-mass microcrysts were nearly all derived from disaggregated metapelites; overgrowths of alkali feldspar on plagioclase and of orthopyroxene on clinopyroxene, and quartz intergrown with alkali feldspar, are the only phases that grew from the rhyolitic liquid. Euhedral cordierite, hercynite, and plagioclase at the margins of some rock fragments grew by reaction of metapelite with liquid.For grains in contact within metapelite inclusions, geothermometers and geobarometers yield estimates of equilibration conditions in the range of 800±100° C and 5±1 kbar. Compositions of phases in the same thin section, but not in the same inclusion, yield broadly erratic P and T estimates indicating disequilibrium among metapelite inclusions. Pyroxene thermometry in the gabbro suite indicates a crystallization temperature of 1020±50° C and a lack of subsequent thermal equilibration with the rhyolitic liquid.The metapelite suite may partly be restite, but much is xenolithic, derived from a vertical interval of perhaps several kilometers, and may have undergone a much earlier episode of melting. The gabbro fragments are accidental xenoliths incorporated as the magma rose. Contaminants (metapelite and gabbro) account for 50 vol.% of the lavas, and cause them to be classified as high-K andesite according to whole-rock major element analysis.The rhyolitic liquid may have originated by partial fusion of metapelites in the lower crust, or by fractional crystallization of mafic mantle-derived magma combined with assimilation of metapelite; the bulk of the evidence favors assimilation-fractional crystallization. Miocene and younger metapelite-contaminated rhyolites also occur in Tuscany, SE Spain, E Morocco, and NW Tunisia, and are associated in each region with mafic silica-undersaturated lavas, implying crustal underplating around the western Mediterranean before, during, and after formation of the Tyrrhenian basin.  相似文献   

An open letter to G. Matheron     

G. M. Philip  D. F. Watson 《Mathematical Geosciences》1987,19(5):453-454

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