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James Glimm Shuling Hou Hongjoong Kim Yoon-ha Lee David H. Sharp Kenny Ye Qisu Zou 《Computational Geosciences》2001,5(3):173-197
We consider numerical solutions of the Darcy and Buckley–Leverett equations for flow in porous media. These solutions depend on a realization of a random field that describes the reservoir permeability. The main content of this paper is to formulate and analyze a probability model for the numerical coarse grid solution error. We explore the extent to which the coarse grid oil production rate is sufficient to predict future oil production rates. We find that very early oil production data is sufficient to reduce the prediction error in oil production by about 30%, relative to the prior probability prediction. 相似文献
236.
跨断裂水准剖面观测在地震监测中的应用 总被引:3,自引:0,他引:3
由于活动地块的相对运动和变形,其边界带往往构造活动强烈,是反映地壳运动的敏感部位。基于上述思路,昆仑山口西8.1级大震发生后,通过大范围监测布设在青藏块体北部地区及周边主要构造带上的水准剖面,在短期内快速获取了大范围的断裂活动信息和不同断裂带对大区域构造应力场变化的响应特征。实践证明,这种监测方式灵活、作业周期短、资料处理快,能及时对震情趋势做出估计,不失为当前区域形变监测工作的一种新的探索。 相似文献
237.
Channel morphology and its impact on flood passage, the Tianjiazhen reach of the middle Yangtze River 总被引:1,自引:0,他引:1
The Tianjiazhen reach of the middle Yangtze is about 8 km long, and characterized by a narrow river width of 650 m and local water depth of > 90 m in deep inner troughs, of which about 60 m is below the mean sea level. The troughs in the channel of such a large river are associated with regional tectonics and local lithology. The channel configuration plays a critical role in modifying the height and duration of river floods and erosion of the riverbed. The formation of the troughs in the bed of the Yangtze is considered to be controlled by sets of NW–SE-oriented neotectonic fault zones, in which some segments consist of highly folded thick Triassic limestone crossed by the Yangtze River. Several limestone hills, currently located next to the river channel, serve as nodes that create large vortices in the river, thereby accelerating downcutting on the riverbed composed of limestone highly susceptible to physical corrosion and chemical dissolution. Hydrological records indicate that the nodal hills and channel configuration at Tianjiazhen do not impact on normal flow discharges but discharges > 50,000 m3s− 1 are slowed down for 2–3 days. Catastrophic floods are held up for even longer periods. These inevitably result in elevated flood stages upstream of prolonged duration, affecting large cities such as Wuhan and a very large number of people. 相似文献
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Wang Yong Hou Zengqian Mo Xuanxue Dong Fangliu Bi Xianmei Zeng Pusheng 《Frontiers of Earth Science》2007,1(3):322-332
More than 140 middle-small sized deposits or minerals are present in the Weishan-Yongping ore concentration area which is
located in the southern part of a typical Lanping strike-slip and pull-apart basin. It has plenty of mineral resources derived
from the collision between the Indian and Asian plates. The ore-forming fluid system in the Weishan-Yongping ore concentration
area can be divided into two subsystems, namely, the Zijinshan subsystem and Gonglang arc subsystem. The ore-forming fluids
of Cu, Co deposits in the Gonglang arc fluid subsystem have δD values between −83.8‰ and −69‰, δ18O values between 4.17‰ and 10.45‰, and δ13C values between −13.6‰ and 3.7‰, suggesting that the ore-forming fluids of Cu, Co deposits were derived mainly from magmatic
water and partly from formation water. The ore-forming fluids of Au, Pb, Zn, Fe deposits in the Zijinshan subsystem have δD
values between −117.4‰ and −76‰, δ18O values between 5.32‰ and 9.56‰, and Δ13C values between −10.07‰ and −1.5‰. The ore-forming fluids of Sb deposits have δD values between −95‰ and −78‰, δ18O values between 4.5‰ and 32.3‰, and Δ13C values between −26.4‰ and −1.9‰. Hence, the ore-forming fluids of the Zijinshan subsystem must have been derived mainly
from formation water and partly from magmatic water. Affected by the collision between the Indian and Asian plates, ore-forming
fluids in Weishan-Yongping basin migrated considerably from southwest to northeast. At first, the Gonglang arc subsystem with
high temperature and high salinity was formed. With the development of the ore-forming fluids, the Zijinshan subsystem with
lower temperature and lower salinity was subsequently formed.
Translated from Mineral Deposits, 2006, 25(1): 60–70 [译自: 矿床地质] 相似文献
240.
基于进化方向遗传算法的四维变分资料同化方法 总被引:7,自引:5,他引:7
数值天气预报模式初始时刻要素场的变分同化问题是一个非线性最优化问题。利用进化方向遗传算法(EDGA)求解该最优化问题,并对理想初始场作数值模拟,结果表明模拟的效果较好。 相似文献