鄂尔多斯盆地旦八油田延长组长3储层研究

三叠系延长组长3储集层灰色细粒长石砂岩储层物性差,属低孔、低渗储层.空隙以粒间孔、溶孔为主,且成岩作用控制孔隙结构.根据岩性、物性特征,把研究区储层分为四类:Ⅰ类好储集层,Ⅱ类较好储集层,Ⅲ类较差储集层,Ⅳ类非储层.     

三峡库区泥灰质岩石斜坡带构造对岩溶地质灾害的控制机理

三峡库区三叠系巴东组(T26)泥灰质岩石岩溶是移民迁建中发现的重大工程地质问题。泥灰质岩石中的构造非常复杂，包括老构造、新构造和表生构造，它们共同控制了岩溶作用。老构造中，褶皱和断裂带等局部构造控制着岩溶的重要部位和重要层位，节理和层理等小构造使岩溶普遍存在。新构造时期地表隆升和河流切割使岩体卸荷松动，岩溶通道扩宽。表生岩溶构造加密了岩溶通道，使岩溶作用增强。三峡库区泥灰质岩石斜坡带地质灾害形成的机理遵循着构造控制下岩溶发育的规律性，致使岩溶地质灾害具有范围广、规模大和结构复杂的特点。岩溶地质灾害的形式包括地面不均匀沉降、地裂缝、滑坡、崩塌、泥石流和地面塌陷。     

Marine and limnic radiocarbon reservoir corrections for studies of late- and postglacial environments in Georgia Basin and Puget Lowland, British Columbia, Canada and Washington, USA

Models of late-glacial environmental change in coastal areas are commonly based on radiocarbon ages on marine shell and basal lake sediments, both of which may be compromised by reservoir effects. The magnitude of the oceanic reservoir age in the inland waters of the Georgia Basin and Puget Lowland of northwestern North America is inferred from radiocarbon ages on shell-wood pairs in Saanich Inlet and previously published estimates. The weighted mean oceanic reservoir correction in the early and mid Holocene is −720±90 yr, slightly smaller than, but not significantly different from, the modern value. The correction in late-glacial time is −950±50 yr. Valley-head sites yield higher reservoir values (−1200±130 yr) immediately after deglaciation. The magnitude of the gyttja reservoir effect is inferred from pairs of bulk gyttja and plant macrofossil ages from four lakes in the region. Incorporation of old carbon into basal gyttja yields ages from bulk samples that are initially about 600 yr too old. The reservoir age declines to less than 100 yr after the first millennium of lake development. When these corrections are accounted for, dates of deglaciation and late-glacial sea-level change in the study area are pushed forward in time by more than 500 yr.     

Structure,composition and bulk properties of upland stream gravels

Upland gravel-bedded streams in the U.K. have received only scant attention from both hydrologists and sedimentologists, but are worthy of further investigation. The sedimentology of three small streams in Teesdale in the Pennines has been examined in detail. Grain-size characteristics, bedforms, structure, composition and packing characteristics of these deposits are described, and compared where appropriate with published information. It is argued that a fuller appreciation of gravel bed composition and morphology should eventually contribute to an improved understanding of sediment transport and deposition mechanisms, and, hence, to improved accuracy in sediment transport and deposition estimates.     

Experimental analysis of reservoir release wave routing in upland boulder bed rivers

Reservoir release wave routing during 33 controlled reservoir releases, along 15 upland boulder bed river channel reaches, on five different regulated rivers were monitored to assess the importance of river channel roughness and reservoir release magnitude on reservoir release wave speeds. Wave speeds varied between 0.52 and 3.01 m s^?1. Reservoir release wave translation, steepening, and attenuation occurred. With high channel roughness values reservoir release wave arrival speed is retarded in comparison to peak stage and wave steepening occurs, but with a reduction in channel roughness reservoir release wave front arrival is accelerated producing attentuation. The threshold between reservoir release wave front attenuation and steepening occurs at a pre-release discharge/channel width of approximately 0.1, an index of channel roughness. The paper also demonstrates, via comparison of observed and calculated reservoir release wave speeds on the River Washburn, Yorkshire, the difficulty of accurately predicting flood wave movement in upland boulder bed channels using existing prediction equations. The calculated values, however, revealed systematic error with pre-release discharge and reservoir release magnitude. Apparently the equations fail to account for the effects of high channel roughness together with pressure gradient forces, induced by rapid rates of stage change on the rising limb of reservoir releases. In order to accurately predict reservoir release wave movement in regulated rivers, this paper demonstrates that hydraulic studies need to be undertaken and pre-release discharges prescribed to determine desired reservoir release wave routing behaviour. Manipulation of the reservoir release pattern at the dam alone, cannot dictate reservoir release wave front form downstream or wave speed.     

三峡库区农业生态经济系统的预警分析

从系统与环境相统一的角度,研究了农业生态经济系统的模型、特征、预警分析的意义和内容;以三峡库区为例,从系统序化的观点,确定了这个系统的社会、经济、环境功能和状态的主要指标的警戒线;并与这些指标的现状、过去与未来趋势值进行对比;分别对现状预警、趋势预警和突变预警进行了评价;最后作了简易的对策探讨．     

乌什水病险水库的坝基灌浆处理与效果检测

新疆乌什水水库为注入式水库,由于坝基严重渗漏,被鉴定为C级病险库。因其具有重要的防洪和灌溉作用,必需对坝基进行防渗处理,以保证其正常安全运营。根据坝基的工程地质条件,在工程设计和施工中确定了坝基的加固防渗和帷幕灌浆原则,并且根据坝基不同岩性、不同透水性,采取不同的钻孔和灌浆施工工艺,探索出一套适合本工程的灌浆工艺。这保证了施工的顺利进行和和工程质量,提高了施工效率,同时节约了大量资金。灌浆完成后运用压水试验对固结灌浆和帷幕灌浆效果进行了验证,同时通过比较坝基实施治理措施前后渗漏量,以及对泉水和湿地的观测及观察等多种手段对帷幕灌浆质量进行检查,结果表明灌浆质量和灌浆效果良好,达到了坝基防渗的目的。     

东河砂岩钙结成岩作用的主要特征

石炭系底部的东河砂岩是一套优质储集层和富油层,也是塔里木盆地的主要产油层.本文从砂岩的成岩作用入手,通过对哈得4油田钙质胶结物作用的细致研究,识别出3期同生钙结成岩作用和4期表生钙结成岩作用,并总结了淡水方解石的矿物特征.结合东河砂岩的时空展布特征,确认了东河砂岩在沉积-成岩过程中遭受过抬升剥蚀,目前哈得4油田不足30 m的东河砂岩应为残余厚度.     

塔里木盆地轮南地区轮南2井油藏的注入史研究--来自流体包裹体的证据

轮南 2井为轮南潜山构造 2号高点上的一口高产油气井 ,主要产层为三叠系 ,其次为侏罗系。通过对轮南 2井油藏中流体包裹体分布特征和成分研究 ,结合轮南地区构造演化史 ,埋藏史和生烃史分析 ,明确了塔里木盆地轮南 2井三叠系油藏主要为一次油气大规模注入形成 ,油气注入时间主要在 14～ 16 Ma左右 ,油源来自于中晚奥陶纪烃源岩。侏罗系油藏则具有两次的油气注入 ,第一次的油气注入主要发生在 14～ 16 Ma左右 ,油源来自于中晚奥陶统烃源岩 ,油气沿断层垂向运移为主 ;第二期油气注入主要发生在晚喜山期 (晚第三纪早期 )之后的最近的 5 Ma间 ,主要为沿重新开启的断层向上运移、注入 ,进行油气再次分配和调整 ,可能还混有少量的陆相油注入