%0 Journal Article %T HEAT TRANSFER AND GROUNDWATER ACTIVITY IN SEDIMENTARY BASINS
沉积盆地中热的传递和地下水活动 %A Wang Jiyang %A Xiong Liangping %A Huang Shaopeng %A
汪集旸 %A 熊亮萍 %A 黄少鹏 %J 第四纪研究 %D 1996 %I %X Heat transfer and groundwater activity are of significant importance in basin dynamics. Theoretically, it relates to the basin formation and development.Practically, these two issues play a crucial role in understanding the generation, migration and deposition of basin-related energy and mineral resources such as coal, oil and gas as well as geothermal resources. Heat transfer and groundwater flow in sedimentary basin can be expressed by the following two equations:Where A is heat generation; T, temperature; c, specific heat of water; v, water flow vector; τ, shear stress; vs, ρs, and cs, are moving rate, density and specific heat of country rock respectively; h, water head; ρ, density; K=kρg / μ, k, permeability; g,acceleration of gravity; μ;kinematic viscosity; α, bulk compressibility; αt, thermal diffusivity; , porosity; Ss, specific reservoir; σt,average total stress; t, time.It must be pointed out that due to the complexity of geological structure of sedimentary basins, the parameters in equations (1) and (2) are non-linearly variable with time and space. For instance, the hydraulic transmmissivity (K) is functioned with permeability of rock strata, density and viscosity of groundwater. It is well-known that the permeability is related to the porosity and the specific surface area of rock strata, and the density, viscosity are temperature-dependent. The variation of hydraulic transmmissivity appears to be much more complicated in fracture/ fault zones. Experiments showed that the bulk compressibility (α) is dependent on rock type and composition. Furthermore, the bulk compressibility of unconsolidated sediments is a function of stress. Below 1 km depth, α varies within the range of 10-9/Pa to 10-11 /Pa. In addition, during the evolution of sedimentary basins, the thickness and lithology of sediments change with time. Subsidence, sedimentation, uplift and erosion make the topography and surface relief of sedimentary basin and the structure of aquifer changed greatly, which finally lead to the change of porosity and other thermo-physical properties. Therefore, the heat transfer and groundwater activity in sedimentary basins must be treated as a 4D problem which requires precise solution.Commonly, finite difference and finite element methods are applied to solve these equations numerically. With the development of computer technology, the finite ele-ment method develops rapidly because it has much more advantages and can meet various requirements of a geological model. Garven and Toptygina2] modelled the coupled heat transfer and water flow with variable density for a large-scale sedimentary basin and good results were obtained. Ge and Garven3] studied the complex groundwater flow pattern during the dynamic evolution of a foreland sedimentary basin by using finite-element modelling method. The results indicated that the evolution of flow pattern associated with the development of the basin can be divided into three stages: 1) At early stage, th %K heat transfer %K groundwater activity %K the Liaohe Basin of North China
热传递 %K 地下水活动 %K 辽河盆地 %K 沉积盆地 %U http://www.alljournals.cn/get_abstract_url.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&cid=621CF755B1A341E5&jid=EA07051745CDC8D89D5F01A3A4CFE6A9&aid=743986C7509E847114B02B709CCE7FE2&yid=8A15F8B0AA0E5323&vid=7801E6FC5AE9020C&iid=0B39A22176CE99FB&sid=2922B27A3177030F&eid=4C100B7696CE9E24&journal_id=1001-7410&journal_name=第四纪研究&referenced_num=1&reference_num=0