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201.
Based on characteristics and trap types of gas reservoirs in large and medium gas fields in China, 4 gas reservoir models
have been established:(i) structural trap gas reservoir model I, formed earlier than or simutaneously with generating of gases;
(ii) structural trap gas reservoir model II, formed later than generating of gases; (iii) fossil weathered residuum gas reservoir
model; and (iV) mud diapir abnormal temperature and pressure gas reservoir model. Distribution patterns of large-medium gas
fields are described with the concept of “sealed compartment”. It is concluded that the inner-compartment area, marginal area
of the compartment and the areas between two overlapped sealed compartments are the most favourable areas for discovering
large-medium gas fields.
Project supported by the “85–102” Chinese National Key Science and Technology Project. 相似文献
202.
203.
关于侵入岩体中金矿床成因研究若干问题的讨论 总被引:9,自引:1,他引:9
各时代、不同类型侵入岩中的金矿床是金矿的主要类型。关于金矿床与岩体的成因关系目前尚存在不同的看法,但传统的岩浆热液成因观点仍居统治地位,其原因往往在于不少研究者把岩液热液成因当成了固定模式应用于具体矿床的研究,而不是建立在综合研究的基础之上。本文结合近年来金矿的研究进展,强调侵入岩中金矿床的研究的研究要综合考虑成岩成矿的时代与时差,成矿流体和成矿物质的来源等各方面因素。金矿床定年的进展研究表明,矿 相似文献
204.
地幔流体及其成矿作用 总被引:7,自引:0,他引:7
地幔流体作为一种重要成矿介质在某些矿床形成过程中起到过重要作用。根据目前地幔流体研究的某些成果,介绍了地幔流体可能与成矿的方式和成矿机制,并举例说明地幔流体与超大型,大型矿床之间的成因联系。 相似文献
205.
206.
重点分析了新疆及边邻地区1980年以来6次7级以上地震前后北天山地下流体动态异常资料,其中3次地震前地下水有短期前兆异常变化,震时同震地震波效应普遍存在,震后异常十分突出且幅度大;以水位为主的水动力学效应反映了大区域应力调整过程具有不可逆特征。水文地球化学参数的变化不敏感。讨论了地下水远程效应与井震距离的关系以及阶跃异常的幅度等问题。 相似文献
207.
Kela 2 Gas Field, with high formation pressure (74.35MPa), high pressure coefficient (2.022) and difficulty of potential test and evaluation, is the largest integrated proved dry gas reservoir in China so far and the principal source for West-East Gas Development Project. In order to correctly evaluate the elastic-plastic deformation of rocks caused by the pressure decline during production, some researches, as the experiment on reservoir sensitivity to stress of gas filed with abnormal high pressure, are made. By testing the rock mechanic properties, porosities and permeabilities at different temperature and pressure of 342 core samples from 5 wells in this area, the variations of petro-physical properties at changing pressure are analyzed, and the applicable inspection relationship is concluded. The average productivity curve with the reservoir sensitivity to stress is plotted on the basis of the research, integrated with the field-wide productivity equation. The knowledge lays a foundation for the gas well productivity evaluation in the field and the gas field development plan, and provides effective techniques and measures for basic research on the development of similar gas fields. 相似文献
208.
Stephen E Laubach Jon E Olson Julia F.W Gale 《Earth and Planetary Science Letters》2004,222(1):191-195
Fluid flow in fractured rock is an increasingly central issue in recovering water and hydrocarbon supplies and geothermal energy, in predicting flow of pollutants underground, in engineering structures, and in understanding large-scale crustal behaviour. Conventional wisdom assumes that fluids prefer to flow along fractures oriented parallel or nearly parallel to modern-day maximum horizontal compressive stress, or SHmax. The reasoning is that these fractures have the lowest normal stresses across them and therefore provide the least resistance to flow. For example, this view governs how geophysicists design and interpret seismic experiments to probe fracture fluid pathways in the deep subsurface. Contrary to these widely held views, here we use core, stress measurement, and fluid flow data to show that SHmax does not necessarily coincide with the direction of open natural fractures in the subsurface (>3 km depth). Consequently, in situ stress direction cannot be considered to predict or control the direction of maximum permeability in rock. Where effective stress is compressive and fractures are expected to be closed, chemical alteration dictates location of open conduits, either preserving or destroying fracture flow pathways no matter their orientation. 相似文献
209.
210.