岩石圈厚度对玄武岩地球化学的控制     

王晓燕 Ellam  RM 《地质科学译丛》1993,10(4):41-46

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格陵兰冰盖在末次间冰期大范围消融的冰岩心证据     

Koer.  RM 施光春 《地质地球化学》1993,(2):47-50

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KERN DSR—11解析测图仪和地理信息系统一体化     

Faig  W 李小鹏 《武测译文》1994,(3):4-10

本文描棕了ＫｅｒｎＤＳＲ－１１解析测图仪与ＧＩＳ环境联合的步骤。讨论了解析测图仪源模式与ＧＩＳ之间数据格多的不兼容问题，源模式或ＧＩＳ的“不相关的独立”操作、计算设备的局限性以及它们对成功地实现一体化所带来的一些问题。介绍了解析测图仪系统和ＧＩＳ的运行机制及用户接口。结论是：在ＧＩＳ之中直接使用摄影测量工作站具有许多优点，而且当使用数字技术时，这此优点有所增强。但是在实现上述一体化系统的过程中，尚  相似文献   

云和降水物理学的理论和观测研究述评：1991—1994年     

Rasm.  RM 《大气情报》1996,16(1):26-40

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肯尼亚东南部红宝石的成因     

Key.  RM 王奖臻 《国外地质(成都)》1992,(4):71-77

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An overview of toxicant identification in sediments and dredged materials   总被引：1，自引：0，他引：1  

Ho KT  Burgess RM  Pelletier MC  Serbst JR  Ryba SA  Cantwell MG  Kuhn A  Raczelowski P 《Marine pollution bulletin》2002,44(4):286-293

The identification of toxicants affecting aquatic benthic systems is critical to sound assessment and management of our nation's waterways. Identification of toxicants can be useful in designing effective sediment remediation plans and reasonable options for sediment disposal. Knowledge of which contaminants affect benthic systems allows managers to link pollution to specific dischargers and prevent further release of toxicant(s). In addition, identification of major causes of toxicity in sediments may guide programs such as those developing environmental sediment guidelines and registering pesticides, while knowledge of the causes of toxicity which drive ecological changes such as shifts in benthic community structure would be useful in performing ecological risk assessments. To this end, the US Environmental Protection Agency has developed tools (toxicity identification and evaluation (TIE) methods) that allow investigators to characterize and identify chemicals causing acute toxicity in sediments and dredged materials. To date, most sediment TIEs have been performed on interstitial waters. Preliminary evidence from the use of interstitial water TIEs reveals certain patterns in causes of sediment toxicity. First, among all sediments tested, there is no one predominant cause of toxicity; metals, organics, and ammonia play approximately equal roles in causing toxicity. Second, within a single sediment there are multiple causes of toxicity detected; not just one chemical class is active. Third, the role of ammonia is very prominent in these interstitial waters. Finally, if sediments are divided into marine or freshwater, TIEs perforMed on interstitial waters from freshwater sediments indicate a variety of toxicants in fairly equal proportions, while TIEs performed on interstitial waters from marine sediments have identified only ammonia and organics as toxicants, with metals playing a minor role. Preliminary evidence from whole sediment TIEs indicates that organic compounds play a major role in the toxicity of marine sediments, with almost no evidence for either metal or ammonia toxicity. However, interpretation of these results may be skewed because only a small number of interstitial water (n = 13) and whole sediment (n = 5) TIEs have been completed. These trends may change as more data are collected.  相似文献   

The Mars oxidant experiment (MOx) for Mars '96     

McKay CP  Grunthaner FJ  Lane AL  Herring M  Bartman RK  Ksendzov A  Manning CM  Lamb JL  Williams RM  Ricco AJ  Butler MA  Murray BC  Quinn RC  Zent AP  Klein HP  Levin GV 《Planetary and Space Science》1998,46(6-7):769-777

The MOx instrument was developed to characterize the reactive nature of the martian soil. The objectives of MOx were: (1) to measure the rate of degradation of organics in the martian environment; (2) to determine if the reactions seen by the Viking biology experiments were caused by a soil oxidant and measure the reactivity of the soil and atmosphere: (3) to monitor the degradation, when exposed to the martian environment, of materials of potential use in future missions; and, finally, (4) to develop technologies and approaches that can be part of future soil analysis instrumentation. The basic approach taken in the MOx instrument was to place a variety of materials composed as thin films in contact with the soil and monitor the physical and chemical changes that result. The optical reflectance of the thin films was the primary sensing-mode. Thin films of organic materials, metals, and semiconductors were prepared. Laboratory simulations demonstrated the response of thin films to active oxidants.  相似文献   

土壤地球化学在西澳大利亚Yilgarn地块黑旗地区金矿勘查中的应用     

Mazz.  RM 张生辉 《物探化探译丛》1998,(5):12-13

８０年代以来,土壤地球化学已经被 在西澳在利亚Ｋａｌｇｏｏｒｌｉｅ北西约５０ｋｍ的黑旗地区进行金矿勘查的一种有效的技术。１９９１－１９９５年间,澳大利亚矿业公司在一片大约４００ｋｍ＾２的租地区实施了一项系统的土壤地球化学计划;该地区的大部分此前曾经由许多不同的勘查小组用多种地球化学技术进行勘查。一个包含近４００００个样品的ＧＩＳ数据库被集成起来,这些数据部分来自ＭＣＡ的工作,也适当地使用了无前勘查  相似文献   

落基山第三纪聚煤盆地沉积模式及与世界某些煤盆地的对比     

Flor.  RM 秦勇 《国外煤田地质》1990,(3):4-10

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Reconstruction of contaminant trends in a salt wedge estuary with sediment cores dated using a multiple proxy approach   总被引：2，自引：0，他引：2  

Cantwell MG  King JW  Burgess RM  Appleby PG 《Marine environmental research》2007,64(2):225-246

The Taunton River is a partially mixed tidal estuary in southeastern Massachusetts (USA) which has received significant contaminant inputs, yet little information exists on the history of discharge and the subsequent fate of these contaminants. Three sediment cores taken along a transect were analyzed, reconstructing the spatial and temporal trends of pollution in the estuary. A combination of radiometric dating, contaminant markers, and storm layers from major hurricanes were used to establish age models and sedimentation rates. Age estimates obtained from the different dating methods compared well, establishing an accurate history of contaminant release to the estuary. Polycyclic aromatic hydrocarbons (PAHs) were present in one core at depths corresponding to the early 1860s, earlier than previously established dates of introduction. Temporal and spatial trends of Cr, Cu, Hg and Pb indicated multiple sources of varying input to the river. Polychlorinated biphenyls (PCBs) were present in each of the cores from the 1930s onward, with elevated levels still present in surficial sediments at several sites. A unique organic compound, Topanol, which was produced locally was used as a tracer to track contaminant transport in the river. Tracer data indicates that contaminants are still being transported and deposited to surficial sediments at high concentrations well after their discharge. This reconstruction demonstrates the utility of using multiple dating proxies where often the sole use of radiometric dating techniques is not an option and provides insights into the fate of contaminants discharged decades ago but continue to represent environmental risks.  相似文献