5次中强震前河源地电台地电阻率的异常变化     

秦乃岗  刘昌谋 《华南地震》1998,18(3):46-51

１９７５￣１９９１年间,广东河源市新丰江水库区发生了５次ＭＬ４．７￣５．１级地震。距震中１０ｋｍ以内的河源黄子洞地电台记录到了震前不同程度的地电阻率异常变化。采用距平法消除年变干扰后异常延续时间一般为３个月左右,电阻率异常下降幅度在１％左右。利用《指南》中的震兆异常信度分析法确认其异常信度后,利用模糊信息处理法对异常判定地震三要素进行了计算,结果与实际基本符合。  相似文献   

RESERVOIR SEDIMENTATION AND LAND USE IN TAIWAN WUSHEH WATERSHED     

Su Chin CHEN 《国际泥沙研究》1998,(3)

ＲＥＳＥＲＶＯＩＲＳＥＤＩＭＥＮＴＡＴＩＯＮＡＮＤＬＡＮＤＵＳＥＩＮＴＡＩＷＡＮＷＵＳＨＥＨＷＡＴＥＲＳＨＥＤＳｕＣｈｉｎＣＨＥＮ１ＡＢＳＴＲＡＣＴＷｕｓｈｅｈＲｅｓｅｒｖｏｉｒｉｓａｇｏｒｇｅｔｙｐｅｈｙｄｒｏｐｏｗｅｒＲｅｓｅｒｖｏｉｒｏｎＷ...  相似文献   

EXTREME RESERVOIR SEDIMENTATION IN AUSTRALIA:A REVIEW     

Hubert CHANSON 《国际泥沙研究》1998,(3)

ＥＸＴＲＥＭＥＲＥＳＥＲＶＯＩＲＳＥＤＩＭＥＮＴＡＴＩＯＮＩＮＡＵＳＴＲＡＬＩＡ：ＡＲＥＶＩＥＷＨｕｂｅｒｔＣＨＡＮＳＯＮ１ＡＢＳＴＲＡＣＴＩｎｔｈｅｐａｐｅｒ,ｔｈｅａｕｔｈｏｒｒｅｖｉｅｗｓｔｈｅｐｒｏｂｌｅｍｏｆｒｅｓｅｒｖｏｉｒｓｉｌｔａｔｉ...  相似文献   

PREDICTING RESERVOIR SEDIMENTATION WITH 2D MODEL FLOODSIM     

W.BECHTELER  M.NUJIC 《国际泥沙研究》1998,(1)

ＰＲＥＤＩＣＴＩＮＧＲＥＳＥＲＶＯＩＲＳＥＤＩＭＥＮＴＡＴＩＯＮＷＩＴＨ２ＤＭＯＤＥＬＦＬＯＯＤＳＩＭＷ．ＢＥＣＨＴＥＬＥＲ１ａｎｄＭ．ＮＵＪＩＣ２ＡＢＳＴＲＡＣＴＰｒｅｄｉｃｔｉｏｎｏｆｓｅｄｉｍｅｎｔａｔｉｏｎｉｓｖｅｒｙｉｍｐｏｒｔａｎｔｂｅｆ...  相似文献   

鄂尔多斯盆地中部气田奥陶系马五1层的古岩溶作用与天然气富集     

傅强  王家林 《海相油气地质》1998,3(2):29-33

鄂尔多斯盆地中部气田的储层为奥陶系马家沟组白云岩风化壳,马五１层为其主力气层,该层可分为四个小层,沉积相为分布稳定的蒸发潮坪环境,经历了表生期和浅、深埋藏期岩溶作用,天然气主要聚集在岩溶孔洞缝中。  相似文献   

白山、丰满水库群实时洪水联合调度系统设计与开发   总被引：5，自引：0，他引：5       下载免费PDF全文

程春田  李新亭 《水科学进展》1998,9(1):29-34

利用面向对象程序设计技术,在中文窗口平台下,设计开发了功能齐全、界面友好、操作灵活、信息丰富,具有很强实用性的白山、丰满水库群实时洪水联合调度系统,可迅速完成从实时遥测降雨信息的采集到两库产、汇流预报和洪水联合调度方案的制定、评价、选择的全过程,简要介绍了系统开发策略及系统设计中的一些主要关键技术及其实现过程,对开发其它水库及水库群防洪调度系统具有重要参考价值。  相似文献   

Siltation analysis in the Neyyar reservoir and forest degradation in its catchment: a study from Kerala state, India     

D. S. Suresh Babu  V. Nandakumar  B. John  B. K. Jayaprasad  S. V. Pramod 《Environmental Geology》2000,39(3-4):390-397

 Impact of catchment erosion and the resultant reservoir siltation from a tropical environment is reported here to discuss the effect of a reservoir in the natural degradation of an evergreen-forested segment. While an area of 8.01 km² has been affected by direct inundation at the full reservoir level, another 2.6 km² area once under thick forest cover, had also lost its identity over the last 38 years by indirect degradation. This zone mainly falls in the confluence of tributaries, namely Neyyar and Mullayar, with the reservoir. The capacity of the reservoir was found to be reduced by 28.8 Mm³ during this period and the annual average loss is calculated as 0.75 Mm³ (0.71%), indicating the intensity of erosion from the catchment zone. In case the proposed upper dam in the reservoir comes into existence, an additional area of 2.4 km² from the virgin forest would be submerged and more area would face degradation around the inundated zone. Received: 29 July 1998 · Accepted: 16 November 1998  相似文献   

鄂尔多斯盆地南部旬邑-宜君地区中生界储层特征   总被引：1，自引：0，他引：1  

张学例  王代国  陈淑惠 《地球科学与环境学报》2000,22(4)

对鄂尔多斯盆地南部旬邑 -宜君地区中生界主要储集层——直罗组、延安组、延长组储层特征从沉积相、砂体纵向展布、岩性和物性等几方面进行了简要论述。通过研究指出本区储层具有低孔、低渗的特点。在纵向上以直罗组储层相对最好 ,延安组次之 ,之后才是三叠系延长组。储集层普遍具有岩性细、成岩后生变化强烈的特点。由于储层低孔、低渗 ,因此 ,油层的压裂改造措施必不可少  相似文献   

pT-effects of Pleistocene glacial periods on permafrost,gas hydrate stability zones and reservoir of the Mittelplate oil field,northern Germany     

S. Grassmann  B. Cramer  G. Delisle  T. Hantschel  J. Messner  J. Winsemann 《Marine and Petroleum Geology》2010

During the past two million years low surface temperatures as well as episodically advancing ice sheets from Scandinavia acted on the subsurface pT-regime of northern Germany. Their likely effects on the petroleum system of Schleswig-Holstein were investigated. For the entire Quaternary mean annual ground temperature (MAGT) was reconstructed at a resolution of 1000 years by calibrating oxygen isotope records from ODP-site 659 to the climate of northern Germany of the past 120 kyr. The resulting MAGT trend served as input to an ice sheet model and a permafrost model along a 2D section crossing the petroleum bearing south-western part of Schleswig-Holstein. Here advances and retreats of the Scandinavian ice sheet during Saalian and Elsterian glaciation Stages were reconstructed. Maximum ice thicknesses of up to 1700 m and up to 20 periods of regional permafrost in northern Germany were reconstructed for the past 1.25 million years. Based on a basal heat flow of 50 mW/m² permafrost thicknesses exceeded 100 m during most of these periods, temporarily extending down to depths of more than 300 m. Favourable surface temperatures and long durations of cold periods provided favourable conditions for onshore gas hydrate stability zones at Mittelplate. Implementing these glacial dynamics into 2D basin modelling (PetroMod, IES, Aachen, Germany) of the Mittelplate oil field reveals five phases of gas hydrate stability at depths down to 750 m. The latest of these events occurred during the Weichselian about 20 kyr ago. The effect of the ice sheets on pore pressure in the subsurface strongly depends on the hydraulic boundary conditions at the ice base (e.g. frozen vs. temperate ice sheet base). Excess pore pressure in the reservoir of more than 10 MPa during ice overriding is possible and probable. The calculated temperature effect of the Pleistocene cooling on the Mittelplate reservoir is in the range of 3–7 °C. Even today temperature in the reservoir is still lowered by about 4 °C in comparison to pre-Pleistocene times. Despite the fact that a significant influence of glacial effects on petroleum generation can be ruled out at Mittelplate, we state that pT-effects in reservoirs related to glacial processes in formerly glaciated areas have been underestimated in the past.  相似文献   

Reprint of: Diagenetic controls on evolution of porosity and permeability in lower Tertiary Wilcox sandstones from shallow to ultradeep (200–6700 m) burial,Gulf of Mexico Basin,U.S.A.     

Shirley P. Dutton  Robert G. Loucks 《Marine and Petroleum Geology》2010

Reservoir quality is a critical risk factor in deep to ultradeep reservoirs at depths >4.5 km. Analysis of Paleogene Wilcox sandstones on the upper Texas Gulf Coast provides insight into the evolution of reservoir quality during shallow to ultradeep burial diagenesis. Reduction of porosity and permeability with burial in Wilcox sandstones was evaluated using subsurface samples from 200 to 6700 m, at temperatures of 25–230 °C. Diagenesis and petrophysical properties were interpreted from petrographic data and core analyses. Wilcox sandstones are mostly lithic arkoses and feldspathic litharenites having an average composition of Q₅₉F₂₂R₁₉. Provenance did not change significantly during Wilcox deposition in this area, nor does average sandstone composition vary among lower, middle, and upper Wilcox sandstones. However, composition does vary with sequence-stratigraphic position; lowstand slope-fan deposits contain more rock fragments than do deposits from highstand or transgressive systems tracts. Given observations from this onshore dataset, Wilcox sandstones deposited in deepwater environments in the Gulf of Mexico are likely to contain more rock fragments than their linked highstand equivalents.  相似文献