安塞油田延长组长10_1油层段沉积微相特征分析     

张茹  李文厚  张慧元  李春荣  贾春光 《甘肃地质》2011,(1):68-74

鄂尔多斯盆地安塞油田晚三叠世延长组长101油层段为勘探新层系,本文着重对安塞油田延长组长101期沉积类型、沉积微相进行系统研究认为,研究区长101油层段发育曲流河三角洲沉积体系,主要为三角洲平原亚相,进一步划分出分流河道、天然堤、决口扇、河漫滩4种沉积微相并对不同微相的特征进行了详细的论述。进而分析了研究区长101油层...  相似文献   

祁连山东部不同树龄油松径向生长对气候的响应   总被引：2，自引：0，他引：2  

张芬  勾晓华  苏军德  高琳琳  刘文火  满自红 《冰川冻土》2011,33(3):634-639

利用采自祁连山东部同一坡面油松树轮样芯,对不同年龄组油松树轮宽度年表指数与气候要素的相关分析,研究了不同年龄组油松径向生长对气候要素的响应.结果表明:不同年龄组油松树轮宽度指数对气候变化的响应不完全一致,即在该区域油松树木的径向生长对气候变化的响应与年龄有关.因此,使用该区域的油松树轮宽度指数年表重建过去气候变化时需要...  相似文献   

北京西郊下苇甸剖面寒武系崮山组叠层石生物丘的沉积组构   总被引：10，自引：2，他引：8  

梅冥相  郭荣涛  胡媛 《岩石学报》2011,27(8):2473-2486

北京西郊下苇甸剖面的崮山组,属于寒武系第三统顶部,自下而上从陆棚相泥灰岩向上变浅至鲕粒滩相灰岩,组成一个淹没不整合型三级沉积层序。在该组上部的一层块状鲕粒滩相颗粒灰岩中,发育串珠状分布的、可以归为叠层石生物丘的穹窿状构造。这些叠层石生物丘,典型的地势隆起和突变的边界代表了明显的早期石化作用特征。叠层石生物丘中的柱状叠层石,为典型的泥晶相叠层石,其内部除了黏结较多的三叶虫生物碎屑外,还不均匀地分布着放射-纤维状方解石(或文石？)组成的底栖鲕粒。这些底栖鲕粒,以其较小的粒径、多样的类型、平滑但不连续的鲕粒圈层以及外部边缘的泥晶套等特征,明显区别于宿主岩石中的颗粒滩相悬浮鲕粒,而且表现出较为明显的与微生物活动相关的微组构。鉴于叠层石是典型的微生物席建造物,该叠层石生物丘特别的宏观和微观沉积组构还可以进一步将其归为较为典型的"微生物礁",从而成为研究中奥陶生物大辐射事件之前贫乏骨骼的浅海环境的沉积作用样式、以及更加深入理解这一特殊时期的微生物造礁作用特征提供了一个较为典型的实例。  相似文献   

广西来宾蓬莱滩剖面中上二叠统硅质岩的地球化学特征及沉积背景   总被引：1，自引：0，他引：1  

邱振  王清晨  严德天 《岩石学报》2011,27(10):3141-3155

广西来宾地区中上二叠统广泛发育硅质岩,蓬莱滩剖面和铁桥剖面是本地区中上二叠统出露最好的剖面.本文对蓬莱滩剖面28件硅质岩(分别为中二叠统茅口组3件与上二叠统合山组25件)的主量和稀土元素进行了分析研究,并结合岩石学特征,认为:蓬莱滩剖面合山组硅质岩沉积于受到陆源物质影响的边缘海盆环境,它们的硅质主要来源于硅质生物,为生物成因;而其茅口组硅质岩则沉积于远离陆源物质影响的边缘海盆环境,它们的硅质主要来源于热液,为热液成因.通过与铁桥剖面的热液成因硅质岩的沉积背景对比研究,结果表明:中晚二叠世时期,来宾地区为富硅的边缘海盆环境,而陆源物质输入程度的差异是造成本地区形成不同成因硅质岩的主要因素.  相似文献   

Recently Ratified and Proposed Cambrian Global Standard Stratotype-section and Points     

PENG Shanchi  ZHU Xuejian  ZUO Jinxun  LIN Huanling  CHEN Yong’an  WANG Longwu 《《地质学报》英文版》2011,85(2):296-308

This paper briefly summarizes an officially ratified Global Standard Stratotype-section and Point (GSSP) and a proposed GSSP for global stages of the Cambrian System. The Luoyixi section near Luoyixi town, Guzhang, northwestern Hunan is ratified as the boundary stratotype for the base of the global Guzhangian Stage, which is the upmost stage of an unnamed series termed provisionally as Cambrian Series 3. The GSSP position lies 121.3 m above the base of the Huaqiao Formation in the section, coinciding with the first appearance of the cosmopolitan agnostoid trilobite Lejopyge leavigata. The Duibian B section at Duibian village, Jiangshan, western Zhejiang, is proposed as the boundary stratotype for the base of the proposed global Jiangshanian Stage that is the second stage of the Furongian Series. The proposed GSSP position lies 108.12 m above the base of the Huayansi Formation in the section, coinciding with the first appearance of the cosmopolitan agnostoid trilobite Agnostotes orientalius. This horizon is also with the first appearance of the cosmopolitan polymerid trilobite Irvingella angustilimbata.  相似文献   

对华北中元古代海侵初期"河流相"沉积的重新认识:以天津蓟县剖面为例   总被引：1，自引：0，他引：1       下载免费PDF全文

钟焱  赵亮东  陈留勤  梅冥相 《古地理学报》2011,13(1):21-29

作为中元古代海侵初期一套厚达400余米的非成熟含砾砂岩地层,常州沟组第一段曾被解释为一套河流相沉积序列.然而,来自于蓟县剖面的实际资料表明需要重新审视前人的解释.在蓟县剖面常州沟组最底部的含细砾粗砂岩中,双向交错层理及冲刷面的频繁发育表明了其具有潮汐作用的沉积特点,这种认识否定了海侵初期大面积发育河流而衍生出的"河侵"...  相似文献   

地震资料低程度区构造圈闭的识别方法及应用——以锦州20-A构造为例     

张中巧  王军  吴俊刚  柴永波  王伟 《海洋地质译丛》2011,(4):29-33

高精度三维地震勘探技术的应用提高了构造圈闭的落实程度,降低了油气的钻探风险。但在三维地震资料未完全覆盖且地震资料品质较差的区域,如何利用现有技术手段准确落实构造囤闭,给实际工作带来了困难。针对这些难点,综合应用时间切片技术、二维、三维地震资料联合解释技术、地质模式指导下的构造解释技术、精细构造成图技术,在锦州20-A构造的识别中取得了良好的应用效果,经钻探也获得了很好的油气发现。该套技术组合在类似地区的构造圈闭识别中具有一定的借鉴意义。  相似文献   

Growth rates of Rhizocarpon geographicum lichens: a review with new data from Iceland     

Tom Bradwell  Richard A. Armstrong 《第四纪科学杂志》2007,22(4):311-320

This paper reviews evidence from previous growth‐rate studies on lichens of the yellow‐green species of Subgenus Rhizocarpon—the family most commonly used in lichenometric dating. New data are presented from Rhizocarpon section Rhizocarpon thalli growing on a moraine in southern Iceland over a period of 4.33 yr. Measurements of 38 lichen thalli, between 2001 and 2005, show that diametral growth rate (DGR, mm yr^?1) is a function of thallus size. Growth rates increase rapidly in small thalli (<10 mm diameter), remain high (ca. 0.8 mm yr^?1) and then decrease gradually in larger thalli (>50 mm diameter). Mean DGR in southern Iceland, between 2001 and 2005, was 0.64 mm yr^?1 (SD = 0.24). The resultant growth‐rate curve is parabolic and is best described by a third‐order polynomial function. The striking similarity between these findings in Iceland and those of Armstrong ( 1983 ) in Wales implies that the shape of the growth‐rate curve may be characteristic of Rhizocarpon geographicum lichens. The difference between the absolute growth rate in southern Iceland and Wales (ca. 66% faster) is probably a function of climate and micro‐environment between the two sites. These findings have implications for previous lichenometric‐dating studies, namely, that those studies which assume constant lichen growth rates over many decades are probably unreliable. © British Geological Survey/Natural Environment Research Council copyright 2006. Reproduced with the permission of BGS/NERC. Published by John Wiley & Sons, Ltd.  相似文献   

The rectilinear three-body problem using symbol sequence I. Role of triple collision     

Masaya Masayoshi Saito  Kiyotaka Tanikawa 《Celestial Mechanics and Dynamical Astronomy》2007,98(2):95-120

The dynamical structure of phase space of gravitational Newtonian three bodies which lie on a line (rectilinear three-body system) is studied. We take an initial value plane and classify the points on the plane according to the fate of the orbits starting from the points, using symbol sequences. The structure appearing on the initial value plane with this classification was well studied for the equal-mass case (Tanikawa and Mikkola 2000, Chaos 10, 649–657). In this paper, we follow and clarify the changes of this structure with the mass ratio of three particles.  相似文献   

浅层综合地震勘探方法在隧道工程勘探中的应用     

孙渊 《地球科学与环境学报》1993,(2)

本文论述了浅层地震勘探方法(特别是透射CT技术)在陕北黄土梁峁地区隧道勘探中的综合应用问题,认为在实际勘测中应结合具体的地表地震地质条件因地致宜地选择浅层地震勘探方法技术,以达到使工程勘探结果最佳化的目的。  相似文献