鄯勒油田西山窑组2段沉积微相研究

确定鄯勒地区主力储层西山窑组2段沉积微相展布特征,为后期精细油藏描述提供地质依据.在岩石矿物、沉积构造、粒度分析和地震相研究基础上,对研究区砂体形成水动力条件及沉积环境进行分析,确定该区西2段为三角洲沉积体系,主要沉积微相包括三角洲平原分流河道、沼泽、分流间湾和决口扇,分流河道和决口扇微相构成本区骨架砂体.据单井沉积微相和小层砂体形态对比分析,对小层沉积微相进行研究,掌握了该区西2段内沉积微相的时空展布和变化规律.     

旨田冲银矿点综合物化探异常特征与发现意义

利用综合物化探方法开展多金属矿产资源预查,在安徽省怀宁县发现了旨田冲银矿点。旨田冲银矿点是怀宁成矿区首次发现的银矿点,该银矿点的矿化体产于志留系高家边组中段,具有层控特征,属新矿种、新层位。旨田冲银矿点的发现为该区地质找矿指明了新的方向,在此着重介绍了该银矿点的矿化情况、综合物化探异常特征和找矿效果,并对该区矿产预查阶段勘查模式进行了总结。     

Classification of Complex Reservoirs in Superimposed Basins of Western China

<正>Many of the sedimentary basins in western China were formed through the superposition and compounding of at least two previously developed sedimentary basins and in general they can be termed as complex superimposed basins.The distinct differences between these basins and monotype basins are their discontinuous stratigraphic sedimentation,stratigraphic structure and stratigraphic stress-strain action over geological history.Based on the correlation of chronological age on structural sections,superimposed basins can be divided into five types in this study:(1) continuous sedimentation type superimposed basins,(2) middle and late stratigraphic superimposed basins,(3) early and late stratigraphic superimposed basins,(4) early and middle stratigraphic superimposed basins,and(5) long-term exposed superimposed basins.Multiple source-reservoir-caprock assemblages have developed in such basins.In addition,multi-stage hydrocarbon generation and expulsion,multiple sources,polycyclic hydrocarbon accumulation and multiple-type hydrocarbon reservoirs adjustment,reformation and destruction have occurred in these basins.The complex reservoirs that have been discovered widely in the superimposed basins to date have remarkably different geologic features from primary reservoirs,and the root causes of this are folding,denudation and the fracture effect caused by multiphase tectonic events in the superimposed basins as well as associated seepage,diffusion,spilling,oxidation,degradation and cracking.Based on their genesis characteristics,complex reservoirs are divided into five categories:(1) primary reservoirs,(2) trap adjustment type reservoirs,(3) component variant reservoirs,(4) phase conversion type reservoirs and (5) scale-reformed reservoirs.     

泉州市街道灰尘重金属污染评价

对泉州市街道灰尘中8种重金属元素Cu,Zn,Pb,Ni,Cr,Cd,Mn,Co的含量水平和分布特征进行分析,并采用地积累指数法对其污染状况进行评价。结果表明,泉州市街道灰尘中上述重金属元素平均含量分别是泉州市土壤背景值的7.12,27.36,12.80,6.94,2.29,28.49,1.64,3.2倍;与国内外城市街道灰尘中重金属平均含量相比,泉州市街道灰尘中上述重金属元素平均含量处于中等—偏高水平;Cr,Cu,Pb在工业区含量明显高于其它功能区,而Cr,Cu,Co,Ni含量在农业区最低。地累积指数评价结果表明,Zn为偏重度污染,Cd为中度污染,Cu,Pb,Ni为偏中度污染,Co为轻度污染,Cr,Mn为无污染。     

苏通大桥二期试桩后压浆的施工及效果检测

随着高层建筑和大型桥梁的兴建,钻孔灌注桩在工程中已得到了极为广泛的应用。但是,钻孔灌注桩的固有缺陷,例如孔底沉渣、孔壁泥浆、端阻力、侧阻力发挥不同步等,限制了其承载力的发挥并且沉降较大。由此,钻孔灌注桩压力注浆技术应运而生,并被逐渐应用于工程实践中。所以,对桩的后压浆施工工艺、受力机理等技术问题进行研究是非常重要的。在国内外现有的理论研究和工程应用基础上,通过对苏通大桥Ⅱ期的试桩工程施工,详细阐述了桩端后压浆技术的具体应用。同时,利用钻孔取心及CT检测技术分析后压浆的施工效果。     

洼地开采地下水的地质环境效应研究——以天津市黄港洼应急水源地为例

天津市是我国水资源缺乏、人均占有淡水资源最少的城市之一,也是我国地面沉降最为严重的地区之一。地面沉降现已成为天津市的主要地质灾害,并在一定程度上制约着天津城镇的可持续发展。天津市平原区洼地众多,这些洼地大部分是天津市的湿地分布区。在洼地内建设应急地下水水源地,既可以起到为城区供水,缓解城区的地面沉降,又可以改善洼地生态环境的作用。     

华北板块南缘安徽青白口纪-早奥陶世层序地层与格架

华北地台南缘,主要出露青白口纪—早古生代地层,属被动大陆稳定克拉通盆地发育过程,以台地碳酸盐沉积为主。通过对十余条实测剖面及主干、辅助路线的观察研究,青白口纪—早古生代奥陶纪早期,测区可区分出二个巨层序、十二个三级层序。本文通过三级层序的划分,建立了华北地台南缘青白口纪—早古生代奥陶纪早期层序地层格架、探讨了各岩石地层单位的变化规律。     

华蓥山北倾没端地区石炭系沉积相研究

华蓥山北倾没端地区石炭系地层是发育在志留系侵蚀面上的一套碳酸盐台地相沉积,主要为晶粒白云岩和颗粒白云岩。根据对其沉积物特征、沉积组合和测井相的综合分析,认为研究区主要发育有两种沉积相,三种沉积亚相,并可细分为膏云坪、膏盐潮池、生屑颗粒滩、鲕粒颗粒滩、滩间泻湖等微相。在石炭系黄龙组沉积早期区内主要处于干燥炎热的蒸发台地环境,随着海水的缓慢侵入以及气候的变化,黄龙组沉积晚期逐渐形成了局限台地相的沉积格局。     

The Triassic age for oceanic eclogites in the Dabie orogen: Entrainment of oceanic fragments in the continental subduction

Low-temperature and high-pressure eclogites with an oceanic affinity in the western part of the Dabie orogen have been investigated with combined Lu–Hf and U–Pb geochronology. These eclogites formed over a range of temperatures (482–565 °C and 1.9–2.2 GPa). Three eclogites, which were sampled from the Gaoqiao country, yielded Lu–Hf ages of 240.7 ± 1.2 Ma, 243.3 ± 4.1 Ma and 238.3 ± 1.2 Ma, with a corresponding lower-intercept U–Pb zircon age of 232 ± 26 Ma. Despite the well-preserved prograde major- and trace-element zoning in garnets, these Lu–Hf ages mostly reflect the high-pressure eclogite-facies metamorphism instead of representing the early phase of garnet growth due to the occurrence of omphacite inclusions from core to rim and the shell effect. An upper-intercept zircon U–Pb age of 765 ± 24 Ma is defined for the Gaoqiao eclogite, which is consistent with the weighted-mean age of 768 ± 21 Ma for the country gneiss. However, the gneiss has not been subjected to successive high-pressure metamorphism. The new Triassic ages are likely an estimate of the involvement of oceanic fragments in the continental subduction.     

三叠纪嘉陵江期华蓥山同沉积断层的沉积、储层响应

对于断裂带在地质历史时期活动特点的认识,因多期次、不同活动性质的叠加改造而难以确定。以四川盆地南部嘉陵江组为例,通过三叠纪嘉陵江期华蓥山断裂带两侧的沉积、储层的研究发现沉积、储层响应与断面倾向南东、东侧下降的观点矛盾。主要表现为:在非浅滩化的嘉三期,紧邻断裂带西北侧的下降盘地层异常增厚;浅滩化的嘉一晚期—嘉二1期,东南侧的泸州古隆起地区颗粒岩累计厚度较西北侧增厚;另外,断层东南侧的颗粒岩发育早期岩溶型储层,而在西北侧这类储层欠发育。结果表明在三叠纪嘉陵江期华蓥山断裂带的断面倾向北西,为西侧下降的同沉积正断层。