准噶尔盆地玛湖凹陷百口泉组相对湖平面升降规律研究

准噶尔盆地三叠系百口泉组相对湖平面升降规律认识不清,制约了对百口泉组沉积体系分布与演化的分析。在高分辨率层序地层学理论指导下,综合钻井、测井等资料,采用传统定性分析与定量的测井小波变换分析相结合的方法,对准噶尔盆地玛湖凹陷斜坡区三叠系百口泉组进行高精度层序地层划分,将百口泉组定量划分为1个长期层序,4个中期层序,16个短期层序,126个超短期层序;对126个超短期层序进行Fisher图解的定量分析,结果显示百口泉组沉积时期湖平面升降总体表现出持续上升的特征,内部又可划分为多个次级湖平面升降旋回,百口泉组一段（T₁b₁）、百口泉组二段（T₁b₂）、百口泉组三段（T₁b₃）与三次湖平面持续上升过程相对应,百口泉组三段（T₁b₃）湖平面达到百口泉组时期的最大规模。通过对比前人研究成果和钻井地质信息,认为相对湖平面升降曲线具有很高的可信度。     

粗粒碎屑岩砾石定向性定量表征方法及应用

砾石定向性可用于辅助判断粗粒沉积物沉积环境的介质动力性质与强度。在岩芯图像分析与测量的基础上,运用砾石长轴视倾角玫瑰花图中任意相邻三个小扇形的半径之和的最大值（参数a）和小扇形半径大小偏离程度（参数σ）对玛湖地区百口泉组砂砾岩中砾石定向性进行等级划分和定量表征。通过该方法的应用,建立了该区不同级别砾石定向性的定量划分方案:有明显定向性（a大于35%且σ大于4）、有一定定向性（a大于35%且σ小于4）、有模糊定向性（a小于35%且σ大于4）、定向性杂乱（a小于35%且σ小于4）。并对研究区典型季节性辫状河道和暂时性辫状河道的定向性进行了实测,结果表明季节性辫状河道中σ为4.8~8.13,a为40%~62%,而暂时性辫状河道中σ小于4,a小于35%。该方法能够有效表征砾石定向性,并为沉积环境判断提供依据。     

Dimorphism in Calceola sandalina (Linneé, 1771)

Based on studying the ontogenetic development of Calceola sandalina in the Early Devonian Yukiang Formation from Guangxi Zhuang Autonomous Region, South China, it is for the first time to issue the evidence indicating the existence of sexual dimorphism in Calceola sandalina. The new discovery will add important data on sexual dimorphism throughout the non-colonial fossil metazoan, and it also may throw lights on studying the taxonomy and phylogeny of Calceola sandalina and its relevant taxa.     

Hydrocarbon accumulation model of the Cretaceous in southern China

The Cretaceous in southern China is mainly a set of red and mauve clastic rock, with evaporation layers. For lack of source rock, it has been paid little attention to in the exploration process. With the development of research on hydrocarbon exploration, the masses of Cretaceous reservoirs and shows have been found in recent years. This means that the Cretaceous has great exploration potential. According to the research, authors find that the high-quality reservoir and efficient cap rocks develop in the Cretaceous. At the same time, the Cretaceous and underlying Paleozoic-Early Mesozoic marine strata and overlying Cenozoic nonmarine strata constitute a superimposed basin. Moreover, high-quality source rocks developed in the above-mentioned two sets of strata. In the south, especially in the middle and lower Yangtze region since the Himalayan strong rift was associated with a large number of faults, These faults connect the Cretaceous reservoir and its overlying and underlying source rocks, forming the fault-based and unconformity-based discontinuous source-reservoir-cap accumulation assemblages. Because the Cretaceous has the abundant oil and gas from Paleogene source rocks or Mesozoic-Paleozoic source rocks with secondary hydrocarbon generation ability, three types of reservoirs develop in the Cretaceous: “new-generating and old-reservoiring” reservoirs, “old-generating andnew-reservoiring” reservoirs, and few “self-generating andself-reservoiring” reservoirs. The hydrocarbon enrichment depends on two key factors. Firstly, Cretaceous reservoirs are near to the source kitchens, so its oil and gas source is ample. Secondly, the fault system is well developed, which provides the necessary conducting systems for hydrocarbon accumulation.

     

Oil source analysis of Upper Tertiary Shawan Formation in Chepaizi area,in the northwest margin of Junggar basin

Well che89, located in the Chepaizi area in the northwest margin of Junggar basin, acquires high production industrial oil flow, which is an important breakthrough in the exploration of the south foreland slope area of Junggar basin. The Chepaizi area is near two hydrocarbon generation depressions of Sikeshu and Shawan, which have sets of hydrocarbon source rock of Carboniferous to Jurassic as well as Upper Tertiary. Geological and geochemical parameters are proper for the accumulation of mixed source crude oil. Carbon isotope, group composition and biomarkers of crude oil in Upper Tertiary of well Che89 show that the features of crude oil in Upper Tertiary Shawan Formation are between that of Permian and Jurassic, some of them are similar to these two, and some are of difference, they should be the mixed source of Permian and Jurassic. Geochemical analysis and geological study show that sand extract of Lower Tertiary Wulunguhe Formation has the same source as the crude oil and sand extract of Upper Tertiary Shawan Formation, but they are not charged in the same period. Oil/gas of Wulunguhe Formation is charged before Upper Tertiary sedimentation, and suffered serious biodegradation and oxidation and rinsing, which provide a proof in another aspect that the crude oil of Upper Tertiary Shawan Formation of well Che89 is not from hydrocarbon source rock of Lower Tertiary.

     

采空塌陷区地表建筑物变形特征分析及破坏机理研究

采空区建筑物的变形特性研究,一直是采空塌陷灾害的一个重要方向。本文以北京市房山区史家营乡大村涧村采空塌陷为背景,在充分分析采空区上方建筑物砖墙上裂缝形态及分布规律的基础上,从建筑物受力方面探讨了裂缝产生的原因,并采用数值模拟方法对采矿影响下建筑物的变形破坏机理进行浅析,研究结果不仅可为建筑物加固和维修提供依据,还可为采空塌陷区治理提供参考。     

强制海退体系域识别特征及其油气意义

利用地震沉积学、层序地层学的相关理论和方法,结合钻测井数据、地震反射结构特征、均方根振幅属性和滨线迁移轨迹特征等资料,对珠江口盆地白云凹陷北坡21 Ma强制海退体系域的识别特征、演化模式和油气意义进行了探讨,指出该体系域在平行物源方向具有高角度斜交型前积反射,其前端靠近盆地中心发育具丘状反射的盆底扇,滨线迁移轨迹呈向盆地方向逐级下降的趋势。结果表明:强制海退体系域在垂直物源方向发育"U"型的下切谷,内部为平行的地震反射充填结构;测井曲线为漏斗形和箱型的组合特征,表现为多个四级相对海平面变化控制的准层序组,且每个准层序组都具有向上水体变浅和顶部突然变深的特征;强制海退体系域之下为前期层序高位体系域的前三角洲或陆架泥岩,其上沉积了海侵体系域和高位体系域的半深海暗色泥岩,同时受陆架坡折带地层尖灭和断裂沟通深部油源的控制,可形成有利的生、储、盖组合,是寻找岩性油气藏的有利场所。     

从端点走向连续:河流沉积模式研究进展述评

从河道类型的划分、河床演变与河型转换、河道沉积与河流砂体的建筑结构要素、河漫滩沉积、季节性河流与分支河流体系、河流沉积相模式、河流沉积学研究技术与方法等方面对国内外河流沉积模式的研究进展进行了综述,认为近十年来河流沉积学的理论和方法都发生了重要的变化。地貌学家、沉积学家和工程师认识到河道形态是连续可变的,而不是只有4~40多个端点类型。河床的演变受河床比降、流量变幅、河岸沉积物粒度构成、气候、植被以及构造沉降速率等多方面的影响。垂向剖面分析法难以对古河流类型做出正确的判断,运用建筑结构要素分析法重建河道内大型底形的地貌形态是河型判别和河流相模式重建的正确方法。河漫滩是河流沉积事件记录最为齐全的部位,对河漫滩、天然堤和泛滥平原沉积层序的研究能够揭示更多古河流沉积过程以及古环境、古气候和古生物方面的信息。对季节性河流、受季风强烈影响地区的河流、以及不同气候带河流所发育的独特沉积构造和建筑结构要素的研究不断增加。分支河流体系的概念得到越来越多的应用,但也得到不少质疑。我国学者应当注重对现代河流地貌形态和沉积过程的观察,把河床演变学的定量方法与沉积学的观点、理论和资料相结合,利用露头、三维地震资料和探地雷达技术建立河流砂体内部建筑结构信息数据库,加强对古河流河漫滩和泛滥平原的沉积过程、特征及其控制因素的研究,加强对不同构造和气候条件下河流沉积的差异性研究,不断发展河流沉积学研究技术,加强河流沉积学实验室建设和研究队伍建设,加强国际交流与合作,使我国河流沉积学为国家经济社会发展提供更加有力和有效的支撑,为推动国际河流沉积学发展做出中国人自己的贡献。     

Hydrocarbon accumulation model of the Cretaceous in southern China

The Cretaceous in southern China is mainly a set of red and mauve clastic rock, with evaporation layers. For lack of source rock, it has been paid little attention to in the exploration process. With the development of research on hydrocarbon exploration, the masses of Cretaceous reservoirs and shows have been found in recent years. This means that the Cretaceous has great exploration potential. According to the research, authors find that the high-quality reservoir and efficient cap rocks develop in the Cretaceous. At the same time, the Cretaceous and underlying Paleozoic-Early Mesozoic marine strata and overlying Cenozoic nonmarine strata constitute a superimposed basin. Moreover, high-quality source rocks developed in the above-mentioned two sets of strata. In the south, especially in the middle and lower Yangtze region since the Himalayan strong rift was associated with a large number of faults, These faults connect the Cretaceous reservoir and its overlying and underlying source rocks, forming the fault-based and unconformity-based discontinuous source-reservoir-cap accumulation assemblages. Because the Cretaceous has the abundant oil and gas from Paleogene source rocks or Mesozoic-Paleozoic source rocks with secondary hydrocarbon generation ability, three types of reservoirs develop in the Cretaceous: “new-generating and old-reservoiring” reservoirs, “old-generating andnew-reservoiring” reservoirs, and few “self-generating andself-reservoiring” reservoirs. The hydrocarbon enrichment depends on two key factors. Firstly, Cretaceous reservoirs are near to the source kitchens, so its oil and gas source is ample. Secondly, the fault system is well developed, which provides the necessary conducting systems for hydrocarbon accumulation.     

冲断带构造作用控制下的分支河流体系特征及其成因分析

构造运动是控制分支河流体系发育的重要因素之一,其对沉积体系的控制作用一直是研究的热点与难点。前人对挤压、拉张、走滑等类型的盆地均有研究,但在挤压盆地边缘的冲断带中,冲断带对于沉积体系的控制作用研究较少,特别是对冲断带中常发育的分支河流体系（冲积扇）。为研究逆冲作用对分支河流体系的控制作用,通过Google Earth提供的全球地貌影像结合数字高程模型（Digital Elevation Model,DEM）等数据对塔里木盆地西北缘柯坪地区发育的分支河流体系（Distributive Fluvial System,DFS）进行测量研究与沉积学解析,探究盆地边缘逆冲断裂带的DFS几何形态发育特征及影响因素。在研究区内识别DFS共256个。柯坪地区发育的分支河流体系延伸长度范围为0.26~24.58 km,DFS面积范围为0.044~221.987 km2,物源区面积变化范围为0.1~290 km2,DFS坡度范围为0.011~0.182。柯坪地区分支河流体系上发育的河道主要是辫状河,河道下切程度有明显差异。决定柯坪地区分支河流体系发育的主要影响因素有物源供给,气候水文以及构造背景。物源区大小与DFS规模呈正相关;气候通过降雨量与蒸发量来影响DFS发育特征;水文则通过流域分布来影响DFS发育,分布在研究区内柯坪河流域的DFS,发育规模远大于流域外的;构造作用控制沉积区分布、可容空间的大小、坡度等,影响着DFS的分布与发育。研究结果表明:构造作用作为主要因素影响着柯坪地区DFS的分布与发育。在柯坪逆冲带,构造作用通过控制推覆体逆冲高低来影响DFS的大小与坡度。物源区大小也受地层抬升程度控制,地层出露越多,物源区一般越大。将柯坪地区以构造特征分为三个区,每个构造区的DFS具有明显差异。逆冲山前区的物源区域大,DFS规模最大,以扇形为主,坡度低,下切程度低;逆冲前缘区的物源区域较小,DFS规模变小,以长条形为主,坡度增加,下切程度增加;走滑断层区受断层影响,物源区与DFS规模明显变小,以扇形为主,平均坡度最大,平均延伸距离最小,下切程度显著。