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921.
Petrophysical evaluation and its application to AVO based on conventional and CMR-MDT logs 总被引:1,自引:0,他引:1
常规测井为 AVO 分析提供了基础的资料, 成为联系岩石物理与地震资料的桥梁。然而如果储层存在有复杂的流体系统, 如地层被严重地层流体侵入、电阻率响应低及盐水矿化度复杂等的现象, 则常规测井无法提供高质量的测井资料, 导致得出错误的弹性计算结果, 使 AVO 结果与地震资料不吻合。中国渤海湾地区第三系裂缝性储层复杂, 我们利用常规测井和核磁共振测井与模块地层动态测试相结合的组合仪完成了地层评价和储层描述。研究结果表明岩石物理学家利用上述方法技术可以获得诸如空隙度、渗透率、含水饱和度、束缚流体以及空隙压力等重要的储层参数并进一步综合应用这些结果和以实验室测量数据为基础的岩性分析结果进行在地震域岩石物理研究和 AVO 分析。 相似文献
922.
Fang-Chuan Lu Hann-Ming Henry Juang Chi-Chang Liao 《Meteorology and Atmospheric Physics》2007,95(1-2):27-52
Summary A numerical study of a cold surge that occurred from 19–23 December 2001 was conducted to better understand the cold surge
characteristics over the Taiwan area. The National Centers for Environmental Prediction (NCEP) nested Mesoscale Spectral Model
(MSM) was used for this study. Simulation results demonstrated that the nested NCEP MSM captured salient features of the selected
cold surge case. We demonstrated that the local minimum center of the time change of virtual potential temperature (dVPT)
can serve as the location of severe weather of the cold surge for all Taiwan regions. Furthermore, thermodynamic equation
analyses revealed that the leading edge of the cold surge was maintained primarily by meridian thermal advection, while diabatic
heating, vertical and zonal thermal advections were less important.
The cold surge flows were blocked and lifted by the Central Mountain Range (CMR) on its windward side, which increased the
cold surge’s vertical extent upward and increased northwestward tilting in the vertical structure. The flow eventually ascended,
switched direction toward Taiwan, and descended over its northwestern and eastern coasts. The physical and circulatory characteristics
of the cold surge differed noticeably on both sides of Taiwan. The cold surge’s leading edge over the Taiwan Strait was northeast-southwest
oriented and had evident wind shear; on the east side of the island, it was stronger in intensity and faster-moving than its
counterpart on the west side.
Sensitivity experiments revealed that the CMR’s trapping of cold surge flows on its windward side affected cold surge leading
edge characteristics in the following five ways: (1) weakening its intensity over the ocean but enhancing it inland, (2) decreasing
its southward speed, especially over the western low plains region, but increasing its movement on the east coast, (3) increasing
its vertical altitude and narrowing the horizontal extent of its vertical tilting, (4) altering its upper vertical circulatory
structure, and (5) trapping a V-shape density current and enhancing its intensity in connection with the land-sea contrast. 相似文献
923.
本文在综合评价福州市上一轮土地利用总体规划的基础上,指出上一轮土地利用总体规划存在的不足,并结合国家目前的宏观政策和福州市发展的迫切需要,提出新一轮规划修编的基本构想,以更好地发挥规划对福州市社会经济持续健康发展的促进作用。 相似文献
924.
925.
锂作为国家战略性关键紧缺矿产资源,随着现代科技的不断进步,需求量会不断增加。寻找更多的锂矿资源,降低进口依赖度,保障国家资源安全,已是迫在眉睫。黏土型锂矿床作为锂矿的重要类型之一,因分布面积广,资源潜力巨大,越来越受到关注,或可成为锂矿资源的重要补充,既是今后矿产资源勘查的重要方向之一,也是破解锂矿资源紧缺局面的重要途径。黏土型锂矿床已取得不少进展,但也存在一些问题,一定程度上制约了对黏土型锂矿床勘查与开发。通过文献查阅、政府和企业官网的情报收集,结合自身锂矿勘查实践,发现影响和制约黏土型锂矿床勘查与开发的主要问题有五个:一是对黏土型锂矿床资源潜力认识不充分,前景不看好,未给予足够重视;二是缺乏指导勘查工作的规范性依据;三是矿产资源管理与矿业权管理中的不利因素导致勘查力度不足;四是勘查研究过程对于矿石选冶加工技术性能重视程度不够,工艺流程尚不成熟。特别是经济合理、环境友好型的分离提取技术和工艺流程尚在探索阶段;五是可供勘查评价与找矿预测的超常富集成因机制与找矿模型的基础研究尚不深入。针对以上5个问题,提出5个方面的思考与建议,以期加快黏土型锂矿床的勘查开发步伐,可望缓解锂矿资源紧缺和供需矛盾紧张现状。① 呼吁地勘行业重视黏土型锂矿床,将黏土型锂矿床按独立的新矿种类型对待。在充分利用煤、铝等勘查老资料进行二次开发的基础上,对异常区进行验证性调查,圈定可供勘查的找矿有利区段或找矿靶区,为黏土型锂矿勘查部署提供依据;② 通过选择有代表性的区块开展勘查开发试验研究和工程示范,尽快研究出台黏土型锂矿床勘查规范,为今后规范黏土型锂矿勘查工作提供作业依据;③ 从矿权现行管理制度出发,按照“公益先行,基金衔接,商业跟进,整装勘查,快速突破”二十字方针,一方面建议国家和地方政府设置专门的地勘基金,加大地勘基金财政投入,形成一批可供进一步勘查的矿产地,一方面建议矿产资源管理部门释放更多的勘查空间,引入更多社会资本,充分调动勘查市场的活力,为国家提供强有力的资源保障;④ 建议加大锂元素不同赋存状态及其不同占比情形下的分离提取试验投入,尽快形成技术可靠、经济合理、环境友好的工艺流程;⑤ 在梳理并聚焦制约勘查评价、开发利用及找矿预测工作的相关科技问题,通过科技攻关,为锂矿勘查开发提供强有力的科技支撑。通过上述主要瓶颈问题的有效解决,以期实现锂矿资源的重大找矿突破,形成一批可供工业规模开发的黏土型锂矿资源基地,继而从根本上解决锂矿资源紧缺现状和高度依赖进口的局面。 相似文献
926.
Acharee Kaewlaoyoong Chi Thanh Vu Chitsan Lin Chien Sen Liao Jenq-Renn Chen 《Environmental Earth Sciences》2018,77(12):457
The increasing usage and disposal of plastic products could cause the wide distribution of phthalate esters (PAEs) in various environmental media. In this study, six PAE compounds, namely dimethyl phthalate, diethyl phthalate, di-n-butyl phthalate, benzyl butyl phthalate, di(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate, were analyzed in various samples collected from the major plastic industrial area of southern Taiwan, including soil, fertilizer and plastic products, for the purposes of identifying of the possible sources of PAEs and assessing the related health risk. The results show that PAEs in soil samples was dominated by DEHP, with the total concentrations in the range of 0.7?±?0.5, 0.2?±?0.1, and 0.3?±?0.2 mg kg?1 for soil samples from farmland, household back gardens and the roadside, respectively. Contents of PAEs in chemical fertilizer (ND—0 0.87 mg kg?1) were higher than that in organic fertilizer (ND—0.08 mg kg?1), and PAEs concentrations (ND—316 mg kg?1) in plastic mulching films were much less than those in the other types of plastic products (ND—1719 mg kg?1), implying that major sources of PAEs in agricultural soil could be the use of chemical fertilizer and plastic products other than plastic mulching films. Health risk assessment suggested that, via the exposure to PAEs in soil, the potential non-cancer and carcinogenic risks for adults and children are minimal in most cases, except that a “moderate” carcinogenic risk for children exposure to DEHP. The results of this study can serve as a reference for further pollution prevention and environmental protection plans in relation to the industrial operation and discharge as well as the farming practices. 相似文献
927.
After a heavy and continuous rainfall from July 27 to 28, 1981, geological disasters involving large debris flow affected the northern part of Wafangdian City and Pulandian City in Dalian, northeast China, and caused considerable loss of life and property. In recent years, precipitation has continued to increase significantly in Dalian, where the largest debris flow gully, named the Dongmatuncun main ditch, is situated. The Dongmatuncun main ditch is 2 km away from the north side of the right bank of the Fudu River in Wanjialing, Wafangdian City. The geomorphological and hydrological conditions, combined with the characteristics of the debris flow solid source, are conducive to debris flow development. Moreover, with an increase in rainfall, debris flow recurrence becomes increasingly likely. We study the debris flow gully in Dongmatun Village by analyzing the formation conditions through field survey. Fuzzy comprehensive evaluation and analytic hierarchy process are used to evaluate the risk of debris flow. Results indicate that the debris flow gully in Dongmatun Village is highly dangerous and debris flow occurs during heavy rainfall. In addition, the breakout of debris flow can threaten human life and property. 相似文献
928.
汶川地震重灾区,由地震触发的地质灾害数量很多,其中危岩体稳定性判定为灾害治理重点工作。基于可靠度理论,针对坠落式危岩体稳定性极限状态特征,建立其可靠度判定概率极限状态方程,并采用现场量测及概率统计方法,对功能函数中危岩破裂面倾角、危岩等效摩擦角、单位长度危岩体重力、危岩等效黏聚力c、危岩体高度h等基本变量的均值、变异性及分布形态进行确定。基于以上研究成果,建立了坠落式危岩体稳定性可靠度指标计算方法,同时对各基本变量的可靠度敏感性进行研究,研究结果表明:其敏感性由大到小依次为危岩破裂面倾角、危岩等效黏聚力c、危岩的高度h、单位长度危岩体重力、危岩等效摩擦角,研究成果为坠落式危岩体稳定性判定和治理方案设计提供参考依据。 相似文献
929.
Climatic effects of air pollutants over china: A review 总被引:3,自引:0,他引:3
Tropospheric ozone(O3) and aerosols are major air pollutants in the atmosphere. They have also made significant contributions to radiative forcing of climate since preindustrial times. With its rapid economic development, concentrations of air pollutants are relatively high in China; hence, quantifying the role of air pollutants in China in regional climate change is especially important. This review summarizes existing knowledge with regard to impacts of air pollutants on climate change in China and defines critical gaps needed to reduce the associated uncertainties. Measured monthly, seasonal, and annual mean surface-layer concentrations of O3 and aerosols over China are compiled in this work, with the aim to show the magnitude of concentrations of O3 and aerosols over China and to provide datasets for evaluation of model results in future studies. Ground-based and satellite measurements of O3 column burden and aerosol optical properties, as well as model estimates of radiative forcing by tropospheric O3 and aerosols are summarized. We also review regional and global modeling studies that have investigated climate change driven by tropospheric O3and/or aerosols in China; the predicted sign and magnitude of the responses in temperature and precipitation to O3/aerosol forcings are presented. Based on this review, key priorities for future research on the climatic effects of air pollutants in China are highlighted. 相似文献
930.