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201.
Natural resource planning at all scales demands methods for assessing the impacts of resource development and use, and in particular it requires standardized methods that yield robust and unbiased results. Building from existing probabilistic methods for assessing the volumes of energy and mineral resources, we provide an algorithm for consistent, reproducible, quantitative assessment of resource development impacts. The approach combines probabilistic input data with Monte Carlo statistical methods to determine probabilistic outputs that convey the uncertainties inherent in the data. For example, one can utilize our algorithm to combine data from a natural gas resource assessment with maps of sage grouse leks and piñon-juniper woodlands in the same area to estimate possible future habitat impacts due to possible future gas development. As another example: one could combine geochemical data and maps of lynx habitat with data from a mineral deposit assessment in the same area to determine possible future mining impacts on water resources and lynx habitat. The approach can be applied to a broad range of positive and negative resource development impacts, such as water quantity or quality, economic benefits, or air quality, limited only by the availability of necessary input data and quantified relationships among geologic resources, development alternatives, and impacts. The framework enables quantitative evaluation of the trade-offs inherent in resource management decision-making, including cumulative impacts, to address societal concerns and policy aspects of resource development.  相似文献   
202.
A changing climate and more frequent extreme weather events pose challenges to the oil and gas sector. Identifying how these changes will affect oil and gas extraction, transportation, processing, and delivery, and how these industries can adapt to or mitigate any adverse impacts will be vital to this sector’s supply security. This work presents an overview of the sector’s vulnerability to a changing climate. It addresses the potential for Natech hazards and proposes risk reduction measures, including mitigation and adaptation options. Assessment frameworks to ensure the safety of people, the environment, and investments in the oil and gas sector in the face of climate change are presented and their limitations discussed. It is argued that a comprehensive and systemic analysis framework for risk assessment is needed. The paper concludes that climate change and extreme weather events represent a real physical threat to the oil and gas sector, particularly in low-lying coastal areas and areas exposed to extreme weather events. The sector needs to take climate change seriously, assess its own vulnerability, and take appropriate measures to prevent or mitigate any potentially negative effects.  相似文献   
203.
The Caspian Sea, the largest isolated lake in the world, witnessed drastic lake-level variations during the Quaternary. This restricted basin appears very sensitive to lake-level variations, due to important variations in regional evaporation, precipitation and runoff. The amplitude, frequency and drivers of these lake-level changes are still poorly documented and understood. Studying geological records of the Caspian Sea might be the key to better comprehend the complexity of these oscillations. The Hajigabul section documents sediment deposited on the northern margin of the Kura Basin, a former embayment of the Caspian Sea. The 2035 m thick, well-exposed section was previously dated by magneto-biostratigraphic techniques and provides an excellent record of Early Pleistocene environmental, lake-level and climate changes. Within this succession, the 1050 m thick Apsheronian regional stage, between ca 2·1 Ma and 0·85 Ma, represents a particular time interval with 20 regressive sequences documented by sedimentary and palaeontological changes. Sequences are regressing from offshore to coastal, lagoonal or terrestrial settings and are bounded by abrupt flooding events. Sediment reveals a low energy, wave-dominated, reflective beach system. Wave baselines delimiting each facies association appear to be located at shallower bathymetries compared to the open ocean. Water depth estimations of the wave baselines allow reconstruction of a lake-level curve, recording oscillations of ca 40 m amplitude. Cyclostratigraphic analyses display lake-level frequency close to 41 kyr, pointing to allogenic forcing, dominated by obliquity cycles and suggesting a direct or indirect link with high-latitude climates and environments. This study provides a detailed lake-level curve for the Early Pleistocene Caspian Sea and constitutes a first step towards a better comprehension of the magnitude, occurrence and forcing mechanisms of Caspian Sea lake-level changes. Facies models developed in this study regarding sedimentary architectures of palaeocoastlines affected by repeated lake-level fluctuations may form good analogues for other (semi-)isolated basins worldwide.  相似文献   
204.
A method for regional assessment of the distribution of saline outbreaks is demonstrated for a large area (68 000 km2) in north Queensland, Australia. Soil samples were used in conjunction with a digital elevation model and a map of potentially saline discharge zones to examine the landscape distribution of soluble salts in the region. The hypothesis of atmospheric accession of salt was tested for the topographically defined catchment regions feeding into each potentially saline discharge area. Most catchments showed a salt distribution consistent with this hypothesis, i.e. %TSS was large near the discharge areas and decreased rapidly with distance uphill from the discharge areas. In some catchments, however, local saline outbreaks were apparent at significant distances uphill from discharge areas. The possibility of geological sources of this salt was examined by comparing random point distributions with the location of saline points with distance downhill from geological units (excluding points near discharge zones). The distribution of some saline outbreaks was consistent with the occurrence of Cambro‐Ordovician metasediments, Devonian limestone, Upper Devonian–Lower Carboniferous volcanics, and Triassic sediments. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
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