Detecting Changes in Ground Water Quality at Regulated Facilities     

Jim C. Loftis  Jane Harris  Robert H. Montgomery 《Ground Water Monitoring & Remediation》1987,7(1):72-76

The Resource Conservation and Recovery Act (PL 94–580) and related federal and state legislation have mandated routine monitoring of ground water quality at regulated facilities. The objective of the required monitoring activities is detection of adverse changes in ground water quality caused by the facilities.
Both failure to detect pollution and an incorrect determination of pollution can be very expensive. It is crucial, therefore, that monitoring programs be designed and operated to provide statistically sound information. It is equally important that users of ground water quality data understand the nature and limitations of information from monitoring.
To address the preceding issues, the authors present a general approach to analyzing ground water quality data in light of the stated monitoring objective. The suggested approach accounts for "natural" variation in background water quality through pairing of observations. The limitations of quarterly sampling for detecting small changes in quality over a short time frame are discussed.  相似文献   

Quaternary evolution of the great lakes : Edited by P. F. Karrow and P. E. Calkin. Geological association of Canada special paper 30, London, Ontario, 1985, 258 pp     

Jane L. Forsyth 《Quaternary Research》1987,28(3)

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Subtidal distribution of barnacles (Cirripedia: Balanidae) in Chesapeake Bay,Maryland     

Victor S. Kennedy  Jane DiCosimo 《Estuaries and Coasts》1983,6(2):95-101

From 1977 to 1980, samples of barnacles were collected (as opportunities arose) from 61 subtidal locations (mostly oyster beds) around Chesapeake Bay, Maryland. Three species were identified from the area.Balanus improvisus dominated, comprising 83% of the 8,231 barnacles identified, and was collected at all locations but one. It occurred over a collection salinity range of 0.8‰ to 17.9‰.Balanus subalbidus (14% of the barnacles identified) was collected over the same salinity range, but mainly in lower salinity waters.Balanus eburneus was scarce (2% of the barnacles identified) and was collected at higher salinities (8.5‰ to 17.1‰).  相似文献   

Preface     

Thomas D. Demchuk  Jane C. Shearer  Timothy A. Moore 《International Journal of Coal Geology》1995,28(2-4)

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Weathering of sulfidic shale and copper mine waste: secondary minerals and metal cycling in Great Smoky Mountains National Park,Tennessee, and North Carolina,USA   总被引：6，自引：0，他引：6  

Jane?M.?HammarstromEmail author  Robert?R.?SealII  Allen?L.?Meier  John?C.?Jackson 《Environmental Geology》2003,45(1):35-57

Metal cycling via physical and chemical weathering of discrete sources (copper mines) and regional (non-point) sources (sulfide-rich shale) is evaluated by examining the mineralogy and chemistry of weathering products in Great Smoky Mountains National Park, Tennessee, and North Carolina, USA. The elements in copper mine waste, secondary minerals, stream sediments, and waters that are most likely to have negative impacts on aquatic ecosystems are aluminum, copper, zinc, and arsenic because these elements locally exceed toxicity guidelines for surface waters or for stream sediments. Acid-mine drainage has not developed in streams draining inactive copper mines. Acid-rock drainage and chemical weathering processes that accompany debris flows or human disturbances of sulfidic rocks are comparable to processes that develop acid-mine drainage elsewhere. Despite the high rainfall in the mountain range, sheltered areas and intermittent dry spells provide local venues for development of secondary weathering products that can impact aquatic ecosystems.Electronic Supplementary Material  Supplementary material is available for this article if you access the article at . A link in the frame on the left on that page takes you directly to the supplementary material.

Jane M. HammarstromEmail: Phone: +1-703-6486165Fax: +1-703-6486252

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The effect of organic materials on the mobility and toxicity of metals in contaminated soils     

René van Herwijnen  Tim Laverye  Jane Poole  Mark E. Hodson  Tony R. Hutchings 《Applied Geochemistry》2007

Organic materials such as compost are often proposed as suitable materials for the remediation of contaminated brownfield sites intended for soft end-use. In addition to vitalising the soil, they are also believed to immobilise metals thereby breaking contaminant-receptor pathways and reducing the ecotoxicity of the contaminants. However, some research has demonstrated contradictory effects between composts on metal immobilisation. In the present study, four different composts and a liming product containing organic matter (LimeX70) were tested to examine both their metal retention and toxicity reduction capabilities on three different metal contaminated soils. Leaching tests, a plant growth test with Greek cress (Lepidium sativum), an earthworm (Eisenia fetida) survival and condition test and a bacterial toxicity test using Vibrio fischeri were carried out. The leaching test results showed that spent mushroom compost caused an increase in metal concentration in the leachates, while LimeX70 caused a decrease. The variation in behaviour between different amendments for each soil was high, so a generic conclusion could not be drawn. Toxicity tests showed significant reduction of metal bioavailability and toxicity for Greek cress, earthworms and bacteria. The results also suggest that more research should be undertaken to understand the mechanisms involved in metal complexation using different types of organic matter, in order to optimise the use of organic materials like compost for soil remediation.  相似文献   

Caledonian eclogite-facies metamorphism of Early Proterozoic protoliths from the North-East Greenland Eclogite Province     

Hannes K. Brueckner  Jane A. Gilotti  Allen P. Nutman 《Contributions to Mineralogy and Petrology》1998,130(2):103-120

High-pressure metamorphic assemblages occur in mafic, ultramafic and a few intermediate rocks in a gneiss complex that covers an area of approximately 400 × 100 km in the North-East Greenland Caledonides. Detailed petrologic and geochronologic studies were carried out on three samples in order to clarify the P-T-t evolution of this eclogite province. Geothermobarometry yields temperature estimates of 700–800 °C and pressure estimates of at least 1.5 GPa from an eclogite sensu stricto and as high as 2.35 GPa for a garnet websterite. The eclogite defines a garnet-clinopyroxene-amphibole-whole rock Sm-Nd isochron age of 405 ± 24 Ma (MSWD 0.9). Isofacial garnet websterites define garnet-clinopyroxene-orthopyroxene-amphibole-whole rock-(biotite) ages of 439 ± 8 Ma (MSWD =2.1) for a coarse-grained sample and 370 ± 12 Ma (MSWD=0.6) for a finer-grained variety. Overgrowths on zircons from the fine-grained pyroxenite and the eclogite give a pooled ²⁰⁶Pb/²³⁸U SHRIMP age of 377 ± 7 Ma (n=4). Significantly younger Rb-Sr biotite ages of 357 ± 8, 330 ± 6 and 326 ± 6 agree with young Rb-Sr, K-Ar and ⁴⁰Ar/³⁹Ar mineral ages from the gneiss complex and indicate slow cooling of the eclogitic rocks. High-pressure metamorphism may have been at least 439 Ma old (Siluro-Ordovician) with cooling through amphibolite-facies conditions in the Devonian and continued crustal thinning and exhumation well into the Carboniferous. Sm-Nd whole rock model ages indicate the eclogite protoliths are Early Proterozoic in age, while ²⁰⁷Pb/²⁰⁶Pb SHRIMP ages of 1889 ± 18 and 1981 ± 8 from anhedral zircon cores probably reflect Proterozoic metasomatism. The samples have negative ɛ_Nd values (−5 to −16) and elevated ⁸⁷Sr/⁸⁶Sr ratios (0.708–0.715), consistent with field evidence that the eclogite protoliths were an integral part of the continental crust long before Caledonian metamorphism. The presence of a large Caledonian eclogite terrane in Greenland requires modification of current tectonic models that postulate subduction of Baltica beneath Laurentia during the Caledonian orogeny. Received: 9 October 1996 / Accepted: 7 July 1997  相似文献   

Recrystallization of Magnesian Calcite Overgrowths on Calcite SeedsSuspended in Seawater     

Jane S. Tribble  Fred T. Mackenzie 《Aquatic Geochemistry》1998,4(3-4):337-360

The formation and subsequent reactions of magnesiancalcite overgrowths on calcite were investigated bymeans of closed system seeded precipitationexperiments. These experiments demonstrated that(1) thin overgrowths of magnesian calcite are precipitatedon calcite seeds suspended in seawater;(2) the solubilities of the coatings increase outward from theseed crystals as a linear function of the log ofrelative coating thickness;(3) during the period ofthese experiments (up to 5.5 months), the magnesiancalcite coatings continued to increase in thickness,but became less soluble in composition. Thestabilization reaction, referred to asrecrystallization, can be described by the followingequation:Cax Mg(1-x) CO3 + [z + y(x + z)]Ca2++ 2yHCO3- ]= (1 + y)Ca(x + z)Mg(1 - x -z)CO3 + [z + y(x + z - 1)]Mg2++ y CO2 + yH20;]4) recrystallization rate is dependent on solutionsaturation state, with a reaction order of 3.2 forartificial seawater and 4.0 for natural seawater; and(5) by the cessation of the closed system experiments,overgrowth compositions approached that of the stablecalcite (a few mol % MgCO3).Armoring of suspended carbonate particles in thesurface oceans with magnesian calcite overgrowthswould provide an effective barrier to release of theoceanic supersaturation with respect to calcite. Thicknesses of such coatings would be limited by therecrystallization rate of the magnesian calcite. Estimates based on the recrystallization ratesdetermined in this work indicate coatings on the orderof 0.02 µm in thickness could form on particles asthey sink through the mixed layer. According to thesecalculations, the total amount of carbon precipitatedannually in magnesian calcite overgrowths iscomparable to the riverine flux of dissolved carbon tothe oceans. Field observations of severalinvestigators indicate the likely presence ofmagnesian calcite coatings on planktonic particles,and provide evidence for possible recrystallization ofbiogenic magnesian particles in the marineenvironment.  相似文献   

Cosmic-ray exposure ages of the ordinary chondrites and their significance for parent body stratigraphy     

Jane Crabb  Ludolf Schultz 《Geochimica et cosmochimica acta》1981,45(11):2151-2160

²¹Ne cosmic-ray exposure ages have been calculated from literature data for 201 H, 203 L and 38 LL chondrites, corrected for shielding differences when possible. The distributions of exposure ages again show the familiar peaks at 4.5 and 20 Myr for the H's, but no outstanding events for the L's and LL's. If the L-chondrite distribution is interpreted as a series of discrete events, then at least 6 peaks between 1 and 35 Myr are needed to model it. The observations, that every petrologic type occurs in every large peak and that even the higher petrologic types contain solar wind gases, suggest that the parent bodies have been fragmented and reassembled into a megabreccia. For the H chondrites, both large and small peaks contain about 15% solar-gas bearing meteorites, which could mean that surface material has been mixed to depths represented by the largest event, on the order of a kilometer. In contrast, only 3% of the L's contain solar wind, which may be related to breakup of their parent planet. Those L's with especially low radiogenic He (U,Th-He ages < 1 AE) tend to have low exposure ages: their distribution may be biased by a subgroup that had orbits coupling short capture lifetimes with significant solar heating.  相似文献   

Long-term global sea surface temperature fluctuations and their possible influence on atmospheric CO2 concentrations     

Reginald E. Newell  Alfredo R. Navato  Jane Hsiung 《Pure and Applied Geophysics》1978,116(2-3):351-371

Changes of atmospheric CO₂ concentration since 1958 are shown to be related to sea surface temperature changes. The largest contribution to changes arises from the Pacific equatorial upwelling region, with the Indian Ocean and Atlantic contributing only small fractions to the variance. It is hypothesized that the observed relationship is related to the nutrients that are brought up by upwelling cold water, with photosynthesis contributing to a lowering of the partial pressure of CO₂ in the sea and thus to a greater tendency for a flux from the air to the sea.Possible longer term variations of sea temperature and CO₂ are discussed.  相似文献