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排序方式: 共有400条查询结果,搜索用时 375 毫秒
1.
通过对尚家—太平川地区构造演化、烃源岩特征、沉积特征、储盖组合、油水关系及油藏类型和油气成藏特征的分析,研究了本区的石油地质条件,认为烃源岩具有较好的生、排烃能力,分流河道砂体为油气聚集提供较好的沉积环境,良好的储盖组合有利于油气的聚集与保存。研究区没有统一油水界面,尚家地区以岩性—构造油藏为主,太平川地区以构造—岩性油藏为主。区内扶余—杨大城子油层油气成藏受有效性圈闭、优势运移通道、过剩压力、储集条件和构造诱导作用控制。据上述认识确定了研究区下一步的勘探方向,并已在指导勘探实践中取得了较好的效果。 相似文献
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There is a growing concern with the impact of marine operations on the environment. This requires reducing fuel consumption and vessel pollution during operation. On-board computers and satellite communications will enable the operator to reduce fuel consumption and NOX emissions during vessel operations.This paper presents the results of a study on this problem and how such an on-board system could be implemented to reduce fuel consumption and engine NOX emissions. 相似文献
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一种面向网络发布的海洋数据库引擎(英文) 总被引:1,自引:0,他引:1
To meet the requirements of efficient management and web publishing for marine remote sensing data, a spatial database engine, named MRSSDE, is designed independently. The logical model, physical model, and optimization method of MRSSDE are discussed in detail. Compared to the ArcSDE, which is the leading product of Spatial Database Engine, the MRSSDE proved to be more effective. 相似文献
6.
WUXiaofang CAIZhongliang WUGuofeng DUQingyun 《地球空间信息科学学报》2003,6(4):27-31
Through analyzing the principle of data sharing in the database system, this paper discusses the principle and method for integrating and sharing GIS data by data engine, introduces a way to achieve the high integration and sharing of GIS data on the basis of VCT in VC , and provides the method for uniting VCT into RDBMS in order to implement a spatial database with object-oriented data model. 相似文献
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Tectonometamorphic evolution of the Himalayan metamorphic core between the Annapurna and Dhaulagiri, central Nepal 总被引:12,自引:0,他引:12
The metamorphic core of the Himalaya in the Kali Gandaki valley of central Nepal corresponds to a 5-km-thick sequence of upper amphibolite facies metasedimentary rocks. This Greater Himalayan Sequence (GHS) thrusts over the greenschist to lower amphibolite facies Lesser Himalayan Sequence (LHS) along the Lower Miocene Main Central Thrust (MCT), and it is separated from the overlying low-grade Tethyan Zone (TZ) by the Annapurna Detachment. Structural, petrographic, geothermobarometric and thermochronological data demonstrate that two major tectonometamorphic events characterize the evolution of the GHS. The first (Eohimalayan) episode included prograde, kyanite-grade metamorphism, during which the GHS was buried at depths greater than c. 35 km. A nappe structure in the lowermost TZ suggests that the Eohimalayan phase was associated with underthrusting of the GHS below the TZ. A c. 37 Ma 40Ar/39Ar hornblende date indicates a Late Eocene age for this phase. The second (Neohimalayan) event corresponded to a retrograde phase of kyanite-grade recrystallization, related to thrust emplacement of the GHS on the LHS. Prograde mineral assemblages in the MCT zone equilibrated at average T =880 K (610 °C) and P =940 MPa (=35 km), probably close to peak of metamorphic conditions. Slightly higher in the GHS, final equilibration of retrograde assemblages occurred at average T =810 K (540 °C) and P=650 MPa (=24 km), indicating re-equilibration during exhumation controlled by thrusting along the MCT and extension along the Annapurna Detachment. These results suggest an earlier equilibration in the MCT zone compared with higher levels, as a consequence of a higher cooling rate in the basal part of the GHS during its thrusting on the colder LHS. The Annapurna Detachment is considered to be a Neohimalayan, synmetamorphic structure, representing extensional reactivation of the Eohimalayan thrust along which the GHS initially underthrust the TZ. Within the upper GHS, a metamorphic discontinuity across a mylonitic shear zone testifies to significant, late- to post-metamorphic, out-of-sequence thrusting. The entire GHS cooled homogeneously below 600–700 K (330–430 °C) between 15 and 13 Ma (Middle Miocene), suggesting a rapid tectonic exhumation by movement on late extensional structures at higher structural levels. 相似文献
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Late Miocene movement within the Himalayan Main Central Thrust shear zone, Sikkim, north-east India 总被引:7,自引:0,他引:7
E. J. Catlos C. S. Dubey T. M. Harrison M. A. Edwards 《Journal of Metamorphic Geology》2004,22(3):207-226
In the Sikkim region of north‐east India, the Main Central Thrust (MCT) juxtaposes high‐grade gneisses of the Greater Himalayan Crystallines over lower‐grade slates, phyllites and schists of the Lesser Himalaya Formation. Inverted metamorphism characterizes rocks that immediately underlie the thrust, and the large‐scale South Tibet Detachment System (STDS) bounds the northern side of the Greater Himalayan Crystallines. In situ Th–Pb monazite ages indicate that the MCT shear zone in the Sikkim region was active at c. 22, 14–15 and 12–10 Ma, whereas zircon and monazite ages from a slightly deformed horizon of a High Himalayan leucogranite within the STDS suggest normal slip activity at c. 17 and 14–15 Ma. Although average monazite ages decrease towards structurally lower levels of the MCT shear zone, individual results do not follow a progressive younging pattern. Lesser Himalaya sample KBP1062A records monazite crystallization from 11.5 ± 0.2 to 12.2 ± 0.1 Ma and peak conditions of 610 ± 25 °C and 7.5 ± 0.5 kbar, whereas, in the MCT shear zone rock CHG14103, monazite crystallized from 13.8 ± 0.5 to 11.9 ± 0.3 Ma at lower grade conditions of 525 ± 25 °C and 6 ± 1 kbar. The P–T–t results indicate that the shear zone experienced a complicated slip history, and have implications for the understanding of mid‐crustal extrusion and the role of out‐of‐sequence thrusts in convergent plate tectonic settings. 相似文献
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以《全国小震目录》(1965年1月1日~2002年lO月31日)和《四川地震台网快报目录》(2002年11月1日~2003年9月30日)为基础资料,研究了川滇地区地震活动性发展变化的主要特征,并提出“单断裂强震区”和“多断裂强震区”概念。发现川滇地区主要单断裂强震区在发生一些强震之后,已经陆续进入地震平静时段,近期发生强震的能力明显减弱。与此同时,“滇西南”、“龙陵-腾冲”、“丽江-武定”地区分别在较短时段内发生多次强震,表明这几个多断裂强震区陆续进入活跃时段,成为1984年以来川滇地区的地震主体活动区域。多断裂强震区具有区内中小断裂汇集、地质构造复杂、地震活跃时段多次出现、在同一活跃时段内又具有活跃小段与小段间距的小段组合形式等特征。对已有的和可能新生的多断裂强震区进行早期判定,以及对活跃时段、小段组合进行动态跟踪,对于川滇地区地震预报具有重要意义。 相似文献