流体替代技术及应用分析     

郝晓红  ;王闯  ;谢春雨 《海洋地质译丛》2008,(3):1-5

地震技术是研究隐蔽油气藏的关键技术。岩石物理是地震信号与储层性质之间的桥梁，它可以帮助我们更好的理解岩石和流体性质的地震响应。流体替代分析是岩石物理分析的重要部分，它是流体识别和储层定量研究的工具之一，在AVO分析中起了重要的作用。流体替代的理论基础是Gassmann方程。在岩石物理技术指导下，对某工区探井进行了流体替代分析，并根据替代后的结果分析了波阻抗随深度、岩性和含油气性变化的规律，同时根据替代结果进行了AVO正演研究，比较分析了储层中流体分别为盐水、气和油时的响应特征，并据此根据实际的部分叠加道集进行了烃类异常识别。  相似文献   

The effects of rock fragments on hydrologic and hydraulic responses along a slope     

Kou‐Chan Hung  Ken'ichirou Kosugi  Tim Hau Lee  Takahisa Misuyama 《水文研究》2007,21(10):1354-1362

A model describing the three‐dimensional matrix flow along a slope with rock fragments or impermeable blocks was developed. The model was combined with modified Picard's iteration to ensure mass conservation in the unsaturated flow. We found that rock fragments obstruct water flow along the slope. The groundwater table must be raised to provide a sufficient pore water pressure gradient to facilitate water flow, but higher pore water pressure may induce slope failure. We also conducted a bench‐scale laboratory flume experiment to examine the effects of impermeable blocks on downstream seepage flow. In addition, a numerical experiment was conducted to examine how different arrangements of impermeable blocks affect downstream seepage flow and pore water pressure. This research demonstrated that the hydraulic phenomena were affected when impermeable blocks were present, and pore water pressure increased as the position of impermeable blocks was lowered. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

The relationship between rock glacier and contributing area parameters in the Front Range of Colorado     

Jason Janke  Regula Frauenfelder 《第四纪科学杂志》2008,23(2):153-163

Rock glaciers are an end unit of the coarse debris system that links frost weathering and rockfall to debris transport in mountainous environments. By examining topographic and climatic controls on creep, a better understanding of rock glacier formation and evolution could be obtained. A series of statistical tests were run comparing contributing area parameters (width, length, area, slope, headwall height, etc.) and rock glacier variables (width, length, area, thickness, slope, creep and temperature) in the Front Range of Colorado. Results showed that rock glacier width had the strongest correlation with contributing area width due to an abundance of lobate rock glaciers (r = 0.78). Rock glacier area and contributing area size were also related (r = 0.74), but are also a function of talus production factors. Mean surface velocity appears to be better correlated with thickness (r = 0.58) and length (r = 0.62), rather than slope (r = 0.33). Mean annual air temperature had a stronger exponential relationship with maximum velocities (r = 0.76) compared to mean annual velocity (r = 0.60). Front Range rock glacier velocities tend to decrease with warming, suggesting that the volume of ice and debris, rates of shear in plastic layers, or melt water may have a greater influence on deformation. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

浅析翡翠的岩石类型对其比重、折射率的影响   总被引：1，自引：0，他引：1  

谢星  王崇礼  梁婷 《地球科学与环境学报》2004,26(4):24-27,53

翡翠的矿物组成、岩石类型不同，将会对翡翠的比重、折射率产生直接的影响。从翡翠的岩石学、矿物学角度出发，讨论了翡翠的岩石类型，依据组成翡翠的主要矿物的比重和折射率值，建立了翡翠矿物组成成分及含量与其比重、折射率关系图解，确定了各种翡翠的比重、折射率变化范围分别为：2．93～3．60和1．593～1．750；优质翡翠的比重、折射率分别为：3．178-3．240和1．644～1．657．为翡翠的质量评估提供了客观依据。  相似文献   

Concentration–discharge relationships reflect chemostatic characteristics of US catchments     

Sarah E. Godsey  James W. Kirchner  David W. Clow 《水文研究》2009,23(13):1844-1864

Concentration–discharge relationships have been widely used as clues to the hydrochemical processes that control runoff chemistry. Here we examine concentration–discharge relationships for solutes produced primarily by mineral weathering in 59 geochemically diverse US catchments. We show that these catchments exhibit nearly chemostatic behaviour; their stream concentrations of weathering products such as Ca, Mg, Na, and Si typically vary by factors of only 3 to 20 while discharge varies by several orders of magnitude. Similar patterns are observed at the inter‐annual time scale. This behaviour implies that solute concentrations in stream water are not determined by simple dilution of a fixed solute flux by a variable flux of water, and that rates of solute production and/or mobilization must be nearly proportional to water fluxes, both on storm and inter‐annual timescales. We compared these catchments' concentration–discharge relationships to the predictions of several simple hydrological and geochemical models. Most of these models can be forced to approximately fit the observed concentration–discharge relationships, but often only by assuming unrealistic or internally inconsistent parameter values. We propose a new model that also fits the data and may be more robust. We suggest possible tests of the new model for future studies. The relative stability of concentration under widely varying discharge may help make aquatic environments habitable. It also implies that fluxes of weathering solutes in streams, and thus fluxes of alkalinity to the oceans, are determined primarily by water fluxes. Thus, hydrology may be a major driver of the ocean‐alkalinity feedback regulating climate change. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

Zircon U-Pb geochronology of Early Jurassic-Late cretaceous volcanic rocks in North Yellow Sea BasinEI北大核心CSCD     

Wang L.  Xu Z.  Cheng R.  Hu X.  Liu H. 《大地构造与成矿学》2015,(1):179-186

The X-drilling cores of the North Yellow Sea basin reveal two sets of Mesozoic clastic rocks, which are the dark rocks in lower part and the red rocks in upper part, respectively. There are two layers of volcanic rocks at the bottom and the upper part of the dark rock unit. The volcanic rocks at the bottom part are trachytic dacite while rocks at the upper part are clastic dacite. The zircon grains from the upper and lower units of volcanic rocks are euhedral-subhedral columnar crystals and show oscillatory zoning on cathodoluminescence images. 22 tests of zircons in the trachytic dacite from the bottom part yield an age of 141-151 Ma, with weighted mean 206Pb/238U age of 145±2 Ma. Whereas 18 tests of zircons from the sample at the upper part give 206Pb/238U ages around 139-149 Ma with weighted mean 206Pb/238U age of 141±2 Ma, which implies that the X well volcanic rocks belong to Late Jurassic-Early Cretaceous. Comparing with the age and geochemical characteristics of the Mesozoic igneous rocks in Shandong peninsula, we suggest that the igneous rocks from both the North Yellow Sea basin and Jiaolai basin were formed under same dynamic setting, i.e., the subduction related volcano arc and back-arc extension. ©, 2015, Science Press. All right reserved.  相似文献   

Geochemical characteristics and LA-ICP-MS zircon U-Pb age of the Lanhualing granite in Ningguo,Anhui ProvinceEI北大核心CSCD     

Chen F.  Wang D.  Du J.  Xu W.  Wang K.  Yu Y.  Tang J. 《大地构造与成矿学》2015,(2):369-377

The Lanhualing tungsten-molybdenum deposit is a skarn-type deposit located in Ningguo county, Anhui province. This deposit is mainly hosted in the Yinzhubu Formation and the Yanwashan Formation of Ordovician, and genetically related to the Lanhualing granite. The Lanhualing granite belongs to high-K calc-alkaline series with high alkali (Na2O+K2O=4.00%-7.03%), SiO2 (67.87%-74.92%) and MgO (0.62%-1.23%) contents. The granitic rocks show right-dipping chondrite normalized REE patterns with weak δEu anomalies. The granitic rocks are relatively enriched in large ion lithophile elements (LILE) and depleted in high field strength elements (HFSE). The ore-bearing granite was dated at 148.17±0.94 Ma by LA-ICP-MS zircon U-Pb method. The late Yanshanian is the main tungsten mineralization epoch in the South Anhui-north Jiangxi area; and indeed, the Dongyuan, Zhuxi, Yangchuling, Dahutang and other large and super-large tungsten deposits were formed in this period. Geochemical Characteristics of the Lanhualing granite indicate a crustal source but with mantle input under tectonic regime of compression thickening. ©, 2015, Science Press. All right reserved.  相似文献   

A laboratory study on capillary sealing efficiency of Iranian shale and anhydrite caprocks     

《Marine and Petroleum Geology》2015

Caprock has the most important role in the long term safety of formation gas storage. The caprocks trap fluid accumulated beneath, contribute to lateral migration of this fluid and impede its upward migration. The rapid upward passage of invasive plumes due to buoyancy pressure is prevented by capillary pressure within these seal rocks. In the present study, two main seal rocks, from the Zagros basin in the southwest of Iran, a shale core sample of Asmari formation and an anhydrite core sample of Gachsaran formation, were provided. Absolute permeabilities of shale and anhydrite cores, considering the Klinkenberg effect, were measured as 6.09 × 10⁻¹⁸ and 0.89 × 10⁻¹⁸ m², respectively. Capillary sealing efficiency of the cores was investigated using gas breakthrough experiments. To do so, two distinct techniques including step by step and residual capillary pressure approaches were performed, using carbon dioxide, nitrogen and methane gases at temperatures of 70 and 90 °C, under confining pressures in the range 24.13–37.92 MPa. In the first technique, it was found that capillary breakthrough pressure of the cores varies in the range from 2.76 to 34.34 MPa. Moreover, the measurements indicated that after capillary breakthrough, gas effective permeabilities lie in range 1.85 × 10⁻²¹ – 1.66 × 10⁻¹⁹ m². In the second technique, the minimum capillary displacement pressure of shale varied from 0.66 to 1.45 MPa with the maximum effective permeability around 7.76 × 10⁻²¹ – 6.69 × 10⁻²⁰ m². The results indicate that anhydrite caprock of the Gachsaran formation provides proper capillary sealing efficacy, suitable for long term storage of the injected CO₂ plumes, due to its higher capillary breakthrough pressure and lower gas effective permeability.  相似文献   

A review of the assessments of the major fisheries resources in South Africa     

CL de Moor  SJ Johnston  A Brandão  RA Rademeyer  JP Glazer  LB Furman 《African Journal of Marine Science》2015,37(3):285-311

The waters off South Africa's coastline boast a rich mix of commercially fished species. Quantitative assessments of these marine resources have developed from simple methods first applied in the 1970s, to models that encompass a wide range of methodologies. The more valuable resources have undergone regular assessments in recent decades, with frequencies closely related to the management approach employed for each fishery. Many of these assessments form the operating models used to simulation-test candidate management procedures. This paper provides a comprehensive review of the assessments of 11 of the most important fisheries resources in South Africa. Some assessments use simple biomass dynamics models, whereas others are a hybrid of age- and length-based models, each designed to model the specific characteristics of the resource and fishery concerned. Many of the assessments have been disaggregated by species/stock and/or area as related multispecies/stock/ distribution hypotheses have arisen. This paper explores the similarities and differences in the data available and the methods applied. The review indicates that, whereas the status of three of these resources cannot be estimated reliably at present, the status of six resources is considered to be reasonable to good, whereas that of abalone Haliotis midae and West Coast rock lobster Jasus lalandii remains poor.  相似文献   

荔湾3-1外输海底管道中落管抛石技术   总被引：1，自引：0，他引：1  

王猛  孙国民 《海洋工程》2015,33(3):86-92

落管抛石是进行深水抛石的一种工程技术,可作为保证管道稳定性、处理悬跨、抑制隆起屈曲和进行跨越支撑的工程解决方案。系统研究了抛石在波流作用下的稳定性,落石对管道冲击的影响以及施工技术。针对南海环境条件下的抛石稳定理论进行了修正;分析了三层聚丙烯涂层管道在落石冲击下的可接受抛石粒径;提出同时结合石块稳定性结果和管道抗冲击性能要求下的石料分级的方法;最后,对该技术在荔湾3-1外输海底管道的工程应用进行详细阐述。  相似文献