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81.
综合利用岩心分析、测井及动态开发资料研究了扶余油田西一、二区北的剩余油分布规律,所研制的油田中、高含水期确定小层剩余油分布图,解决了油田开发中的动态预测小层剩余油分布的难题,并且对1982年和1992年底的剩余油分布规律作了分析。 相似文献
82.
利用相控模型进行井间参数预测 总被引:18,自引:0,他引:18
储层物性参数在空间的展布,一直是储层非均质性研究的难点,利用分形和蒙特卡洛方法,在精细的沉积微相及小层对比研究基础之上,预测了井间的岩石相分布,并根据取心井资料,建立了各种岩石相的渗透率相控模型,从而预测出井间渗透率的分布。该方法以地质特征为基础,将地质资料与数学方法相结合,充分体现了渗透率在井间既具有连续性,同时变化又非常剧烈的特点,为储层物性空间预测提供了新的思路。 相似文献
83.
锡氢化物是锡的重要迁移形式 总被引:6,自引:1,他引:6
论述了锡氢物的形成条件和物理学特征。在岩浆和热液中,锡以锡氢化物,锡合金氢化物迁移至地壳浅部,锡氢化物,锡合金氢化物被氧化成锡氧化物,锡合金矿物,或与硫,硫化氢作用形成锡的硫化矿物。 相似文献
84.
Sensitivity assessment of strontium isotope as indicator of polluted groundwater for hydraulic fracturing flowback fluids produced in the Dameigou Shale of Qaidam Basin 下载免费PDF全文
Hydrogeochemical processes that would occur in polluted groundwater and aquifer system, may reduce the sensitivity of Sr isotope being the indicator of hydraulic fracturing flowback fluids(HFFF) in groundwater. In this paper, the Dameigou shale gas field in the northern Qaidam Basin was taken as the study area, where the hydrogeochemical processes affecting Sr isotope was analysed. Then, the model for Sr isotope in HFFF-polluted groundwater was constructed to assess the sensitivity of Sr isotope as HFFF indicator. The results show that the dissolution can release little Sr to polluted groundwater and cannot affect the εSr(the deviation of the 87 Sr/86 Sr ratio) of polluted groundwater. In the meantime, cation exchange can considerably affect Sr composition in the polluted groundwater. The Sr with low εSr is constantly released to groundwater from the solid phase of aquifer media by cation exchange with pollution of Quaternary groundwater by the HFFF and it accounts for 4.6% and 11.0% of Sr in polluted groundwater when the HFFF flux reaches 10% and 30% of the polluted groundwater, respectively. However, the Sr from cation exchange has limited impact on Sr isotope in polluted groundwater. Addition of Sr from cation exchange would only cause a 0.2% and 1.2% decrease in εSr of the polluted groundwater when the HFFF flux reaches 10% and 30% of the polluted groundwater, respectively. These results demonstrate that hydrogeochemical processes have little effect on the sensitivity of Sr isotope being the HFFF indicator in groundwater of the study area. For the scenario of groundwater pollution by HFFF, when the HFFF accounts for 5%(in volume percentage) of the polluted groundwater, the HFFF can result in detectable shifts of εSr(ΔεSr=0.86) in natural groundwater. Therefore, after consideration of hydrogeochemical processes occurred in aquifer with input of the HFFF, Sr isotope is still a sensitive indicator of the Quaternary groundwater pollution by the HFFF produced in the Dameigou shale of Qaidam Basin. 相似文献
85.
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87.
轴压下两体力学模型的转化条件及影响因素分析 总被引:1,自引:0,他引:1
接触界面的相互作用是影响工程稳定的重要因素,基于接触面两侧介质的实际受力状态,采用一体两介质力学模型与两体两介质力学模型加以描述。通过一体和两体模型试件的轴压破坏试验,分析了两种模型的力学响应的差异,并认为:一体两介质力学模型在符合一定条件情况下可以转变为两体两介质力学模型。此外,还对影响两种力学模型性能的参数进行了分析。提出对一体两介质力学模型力学性能产生影响的参量是低强度介质与高强度介质的静载极限强度比k以及两种介质之间的黏结力c;对两体两介质力学模型力学性能产生影响的主要参量除了k之外,尚有两种介质的断裂韧度比? 、体积比? 以及界面的粗糙程度 相似文献
88.
A statistical analysis for the Rf/φ method is developed in the paper. The technique provides estimates of Rs, Ri and θ according to Rf and φ. Moreover, we can restore the pattern of initial orientations of marker objects by means of their frequency histogram, provided the strain is homogeneous. It is unnecessary to postulate random initial orientations if the principal directions of strain ellipsoid are known. 相似文献
89.
90.
Mianping Zheng 《Environmental Earth Sciences》2011,64(6):1537-1546
The Chinese salt lake mega-region is controlled by an arid and semi-arid climate, and modern salt lakes are mainly distributed
within areas with mean annual precipitation <500 mm. According to their geomorphological features, structural conditions,
and material composition, salt lakes in China can be broadly divided into four regions. The degrees of exploitation and utilization
of these salt lakes differ because these four regions have experienced different climatic changes and structural activities
and have had their own characteristics of salt lake evolution since the beginning of the Quaternary. The salt lakes in these
regions have different scales, economic value, and technical conditions for traffic. Among others, Jarantai (Jartai) Salt
Lake and Yuncheng Salt Lake are better in terms of comprehensive utilization and environmental protection, and the potash
salt lakes represented by Qarhan are most important in terms of exploitation. At present, there exist many environmental problems
in the salt lake regions of China, especially in remote, small and medium-sized basins, where abusive or wasteful mining,
low recovery, and mining of a single saline mineral have caused impoverishment and large quantities of byproducts. Furthermore,
climatic environmental factors can also cause significant changes of salt lake environment. Since 1987, against the background
of global warming, the climate in the northwest salt lake region has turned warm and wet, and lakes have exhibited a tendency
for expansion and rise, whereas in the east of the region, the climate has remained in a warm dry stage, lake levels have
dropped, and salt lakes have become desertified. With the implementation of the strategy of building an environmentally friendly
society in China, increasing attention is being paid to eco-environmental protection. It is suggested that experience and
advanced techniques in terms of comprehensive utilization, overall development, and environmental protection of salt lakes
at home and abroad be further developed to strengthen observation and monitoring of environmental changes of salt lakes and
build an environmentally friendly, great salt lake industry. 相似文献