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长9储集层属于鄂尔多斯盆地延长组湖泊发育早期,油源关系复杂,前期的沉积作用和后期的成岩作用共同塑造了储层低孔低渗的特征。储层的物性是连结岩性和含油性之间的重要环节,加大对低孔低渗储层物性的分析,有利于储层其他方面特征的研究。在对储层孔隙度和渗透率作深入分析的基础上,使用反映储层孔隙度比较灵敏的声波时差测井曲线,来研究其物性特征。通过建立米产液量和声波时差的对应关系,确定声波时差下限,再根据声波时差和储层物性之间的关系式,最终确定储层孔隙度和渗透率下限,为储层含油性特征、有利区优选等方面的研究提供依据。 相似文献
85.
页岩气地震识别与预测技术 总被引:2,自引:0,他引:2
依据页岩气的地质特点及当前地震勘查技术的水平,指出地震在识别和追踪页岩储层空间分布(包括埋深、厚度以及构造形态)方面具有明显的优势;综合利用测井及地质资料,对页岩储层有机质丰度、含气性等参数进行解释及优选敏感的地球物理参数,进而建立储层特征与地震响应的关系,以此反演预测页岩气储层有利区;运用相干与曲率等属性分析技术、宽方位甚至全方位地震各向异性分析技术、叠前反演技术、横波分裂技术等,可解决储层裂缝和岩石力学特征问题,直接为钻井和压裂工程技术服务;与压裂技术配套发展的微地震监测技术,可实时提供压裂过程中产生的裂缝位置、方位、大小以及复杂程度,并对储层改造方案的有效性作出准确评价。 相似文献
86.
CHEN Meixiang) ZUO Juncheng) LI Peiliang) DU Ling) and LI Lei)) Oceanography Department Ocean University of China Qingdao P. R. China ) Key Laboratory of Coastal Disaster Defence Ministry of Education Hohai University Nanjing P. R. China 《中国海洋大学学报(英文版)》2007,6(2):117-124
Based on a ship survey during January 1998, the characteristics of the flow, the thermohaline properties and the volume transport of the Arabian Sea are discussed. A strong westward flow exists between 10.5?N and 11?N, part of which turns to the south as the Somali current near the coast at about 10?N and the rest turns north. At the passage between the African continent and the So- cotra Island, the northern branch separates into two flows: the left one enters the passage and the right one flows eastward along the southern slope of the island. Off the island the flow separates once more, most of it meandering northeast and a small fraction flow- ing southeast. Volume transport calculation suggests that the tidal transport is one or two orders of magnitude smaller than the total transport in this region and it becomes more important near the coast. The average velocity of the flow in the upper layer (0-150 m) is about 20 cm s-1, with a maximum of 53 cm s-1 appearing east of the Socotra Island, and the subsurface layer (200-800 m) has an aver- age velocity of 8.6 cm s-1; the velocity becomes smaller at greater depths. The depth of the seasonal thermocline is about 100 m, above which there is a layer with well mixed temperature and dissolved oxygen. High-salinity and oxygen-rich water appears near the surface of the northern Arabian Sea; a salinity maximum and oxygen minimum at 100 m depth along 8?N testifies the subduction of surface water from the northern Arabian Sea. Waters from the Red Sea and the Persian Gulf also influence the salinity of the area. 相似文献
87.
The herring roe fishery in Canada's southern Gulf of St. Lawrence is a productive fishery that lies outside the confines of privatized arrangements. Yet, this fishery is compromised by its dependence on the Japanese seafood market. Consideration of the efficiency of this fishery needs to account for the role assumed by this market in setting fishing practices. A more ecologically and economically efficient use of the herring resource requires greater attention to supply chain integration by local harvesters, processors and buyers prior to engaging with distant markets. This is necessary regardless of the property rights regime that is in place. 相似文献
88.
Seismic properties of sediments are strongly influenced by pore fluids. Stiffness of unconsolidated marine sediment increases
with the presence of gas hydrate and decreases with the presence of gas. A strong bottom-simulating reflector (BSR) observed
on a seismic profile in the Makran accretionary prism, offshore Pakistan, indicates the presence of gas hydrate and free-gas
across the BSR. Elastic properties of gas depend largely on pressure and temperature. We, therefore, first determine the elastic
modulus of gas at pressure and temperature calculated at the BSR depth in the study region. The interval velocities derived
from the seismic data are interpreted by the effective medium theory, which is a combination of self-consistent approximation
and differential effective medium theories, together with a smoothing approximation, for assessment of gas hydrate and free-gas.
The results show the saturations of gas hydrate and free-gas as 22 and 2.4% of pore space, respectively, across the BSR. 相似文献
89.
Results from forward modelling of garnet growth and U–Th–Pb chemical dating suggest three periods of metamorphism that affected metapelitic rocks of the Rappold Complex (Eastern European Alps). Garnet first grew during Barrovian-type metamorphism, possibly during the Carboniferous Variscan orogeny. The second period of metamorphism produced monazite and resulted in minor garnet growth in some samples. Variable garnet growth was controlled by changes to the effective bulk rock composition resulting from resorption of older garnet porphyroblasts. Monazite crystals have variable morphology, textures and composition, but all yield Permian ages (267 ± 12 to 274 ± 17 Ma). In samples in which there was Permian garnet growth, monazite forms isolated and randomly distributed grains. In other samples, monazite formed pseudomorphous clusters after allanite. This difference is attributed to higher transport rates of monazite-forming elements in samples which underwent dehydration reactions during renewed garnet growth. The third and final period of garnet growth took place during Eo-Alpine (Cretaceous) metamorphism. Garnet of this age displays a wart-like texture. This may reflect transport-limited growth, possibly as a result of repeated dehydration during polyphase metamorphism. 相似文献
90.
知识产权贸易下的全球地缘科技格局及其演化 总被引:1,自引:3,他引:1
中国崛起,关键在于科技崛起。在当前技术针对与封锁的国际环境中,探讨建构以中国为核心的全球创新网络和科学制定中国未来科技战略是当前创新地理学和地缘政治学交叉之下研究的重点课题,而明晰全球地缘科技格局及其演变过程则是基础所在。本文基于2001—2015年全球国家(地区)间的知识产权进出口数据,在研究全球知识产权贸易格局和网络结构的基础上,探讨了全球地缘科技体系的时空演化特征,得出以下结论:① 全球知识产权贸易网络两极分化显著,是一典型的小世界网络,以美国为核心的金字塔结构不断夯实;② 基于敏感性和脆弱性模型阐释的全球知识产权贸易的非对称依赖性进一步验证了美国是全球地缘科技格局的核心,且其核心地位不断巩固和加强。 相似文献