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1.
闭流坳陷湖盆的气候层序   总被引:1,自引:0,他引:1  
闭流坳陷湖盆以发育气候层序为特征,在理想条件下,气候三级周期的变化基本符合正弦曲线;一个完整的闭流坳陷湖盆气候层序Ⅰ型层序应包括4个体系域:低水位进积楔体系域、水进体系域、高位体系域和强制水退楔体系域;同样一个完整的闭流坳陷湖盆气候层序Ⅱ型层序应包括3个体系域:水进体系域、高位体系域和强制水退边缘体系域。这些体系域在气候周期变化的曲线上有相应的位置,层序界面则位于基准面变化的最低点。  相似文献   

2.
松辽盆地泉四段扶余油层地层层序新认识   总被引:4,自引:0,他引:4  
松辽盆地泉四段扶余油层发育浅水湖泊三角洲相和浅水湖泊相,沉积构造环境属于闭塞浅水坳陷湖盆,其层序特征类似于稳定克拉通盆地层序,也类似于缓坡被动大陆边缘型盆地层序,气候是控制陆相坳陷盆地层序形成的主要因素,三级层序内总体应表现为水进体系域-高位体系域构成1个完整的层序,而低位体系域不发育。通过岩心、录井、地震等资料研究分析,认为泉四段扶余油层是1个三级层序,发育水进体系域和顶部薄层强制水退边缘体系域;泉四段与泉三段地层分界是其层序的底界;泉四段顶界地震反射层T2也是层序边界,是泉四段三级层序的顶界。精确识别和建立地层层序格架对石油勘探开发具有重要的指导意义。  相似文献   

3.
通过综合地层、测井及岩心资料,我们将南海纳土纳台寺中新世特隆布组碳酸盐岩划分出七个完整的沉积层序,每个层序包括低水位体系域,海侵体系域及凝缩层和高水位体系域。  相似文献   

4.
利用层序地层学、沉积学原理和方法,对琼东南盆地古近系陵水组进行了层序划分和沉积体系时空配置关系的研究。建立了陵水组的层序地层格架,将其划分为Els3、ElS2和Elsl三个三级层序,其层序和体系域变化主要受控于凹陷内沉降中心的分布位置,沉积主要受控于盆地边缘的断坡带。每个三级层序低位体系域发育局限,海侵与高位体系域发育。沉积体系构成以扇三角洲、三角洲、滨海平原和浅海为主。探讨了沉积体系的演化,总结了其时空配置关系的特点。  相似文献   

5.
塔里木盆地石炭系层序地层研究   总被引:1,自引:0,他引:1  
应用地震、钻井、测井、岩心、露头及分析化验资料,将塔里木盆地石炭系划分为4个地震层序和6个沉积层序,其中Csq1、Csq2、Csq5层序为工型层序,Csq3、Csq4、Csq6层序为Ⅱ型层序,与标准的工型层序比较,盆地内Ⅰ型层序低位体系域以河流沉积体系和低位扇三角洲沉积体系为特征,缺失盆底扇、斜坡进积复合体等深水沉积体系;Ⅱ型层序中陆架边缘体系域不发育,主要的沉积体系以浅水碳酸岩台地和海岸平原为特征。石炭纪早期层序形成在起伏不平的剥蚀面之上,以填平补齐的充填沉积为主,中后期层序则发育在宽阔平坦的盆地内,层序地层学格架模式可用Van的被动大陆边缘模式来描述。  相似文献   

6.
钻井和地震资料的丰富程度决定了储层预测研究精度。在多井区,利用地震属性及单井沉积相来确定平面沉积相,研究精度高;而在少井、无井区的海域,如何利用地震资料进行沉积储层研究,至今没有一个成熟的方法。渤海湾盆地渤中凹陷西环BZ3-1区钻井较少,完整钻遇到沙河街组的井则更少,以该区的沙河街组为例,基于地震多属性分析技术,结合古地貌分析,半定量确定研究区的沉积体系分布特征。通过三维可视化技术和切片技术的高精度三维沉积体系分析表明,由于三级层序发育于二级层序的不同体系域,会导致三级层序的体系域沉积体发育特征的不同。沙三段SQsl3层序发育于二级层序的低位体系域(LST),其低位体系域的扇体规模要远远大于高位体系域(HST)的扇体;SQs3m层序发育于二级层序的水进体系域(HST),其低位体系域三角洲朵体规模与高位体系域的三角洲朵体相当;SQs3u层序发育于二级层序的高位体系域,其高位体系域三角洲朵体规模远远大于低位体系域的三角洲朵体。  相似文献   

7.
较为全面地回顾了强制海退概念的提出及对传统层序地层学发展的推动作用;结合国内外对强制海退沉积的最新研究进展,探讨了沉积层序体系域四分法的可行性和强制海退体系域的主要沉积特征。  相似文献   

8.
通过大量的地震、钻井、录井、测井等资料分析,针对塔里木东部地区(简称塔东地区)上奥陶统进行了层序地层和沉积学方面的研究,结果表明,塔东地区上奥陶统可识别出1个二级层序、3个三级层序,自下而上分别是层序SQ1、SQ2和SQ3。层序SQ1识别出TST体系域,为一套深水盆地沉积,发育深水盆地、浊流沉积;层序SQ2可三分为LST、TST和HST体系域,LST体系域发育海退背景下的陆架边缘三角洲沉积,TST体系域为快速水进期,发育海相泥岩沉积,HST发育高水位滨岸沉积;SQ3发育浅海沉积,主要为三角洲—滨岸沉积体系。地层层序发育和沉积相分布受控于构造运动、沉积物源供给和相对海平面升降3个因素。3套层序的划分明确了塔东地区上奥陶统潜在的源岩层、储层和盖层的分布,其中层序SQ1为有利的烃源岩层、SQ2陆架边缘三角洲是潜在的有利储层,SQ3发育的滨岸砂岩为已经证实的油气藏。  相似文献   

9.
通过桑沟湾周边海域高分辨率浅地层剖面的地质解译,结合典型钻孔沉积地层的对比分析,揭示了研究区晚更新世以来的层序地层序列。研究表明,桑沟湾周边海域晚更新世以来的地层上覆于基岩之上,自下而上识别出了具有层序意义的3个声学地层单元(SU2、SU1-2、SU1-1),与钻孔的3个沉积地层单元(DU2、DU1-2、DU1-1)对应性良好。桑沟湾周边海域晚更新世以来的层序序列,形成于末次冰盛期低海面时期及早-中全新世高海面以来,自下而上包括低水位体系域(河流-河道充填相沉积)、海侵体系域(潮流沙脊与滨海相沉积)、高水位体系域(浅海相沉积)。研究区低水位体系域受河流下切侵蚀作用,沉积厚度变化较大,介于0~15 m;海侵体系域的沉积厚度普遍介于4.5~5.5 m,分布广泛;高水位体系域由岸向海,自西南至东北沉积厚度逐渐增加,最厚处超过30 m。  相似文献   

10.
通过对胶州湾青岛近海沉积物微古化石及浅层地震资料的综合解释,运用层序地层概念,确定了层序界面的划分方法。初次海泛面之下为河流沉积,微体古生物缺乏,其上岩性以含贝壳的砂质粗粒为主,微古特征表现为低丰度、低分异度。浓缩段岩性为虫孔发育的泥质细粒组分,微古丰度出现最高值。据此可将胶州湾青岛近海层序地层划分为半个三级层序.海进体系域发育海侵边界层、潮沟充填及古滨岸沉积,高位体系域形成大沽河洋河复合三角洲沉积体及湾口两侧的潮汐三角洲沉积体。以层序的方法研究近岸沉积物有利于不同地域不同时代地层间的对比,通过岩性和微体化石及矿物分布等特征综合确定海泛面,在具有多物源、快速沉积特点的近岸海湾有一定的现实意义。  相似文献   

11.
The Rhone Fan is a large Plio-Pleistocene turbidite deposit in the western Mediterranean Sea. The fan is fed from the broad Rhone River delta, but only one canyon, the Petit-Rhone, has fed most of the major turbidite depositional sequences that have been mapped. Slumping of sediment from intercanyon areas on the delta slope also has provided much sediment for the fan. The lack of Recent turbidite deposition on the fan suggests that turbidite sedimentation dominates during glacial low stands of sea level, building major leveed valley sequences, while surficial slumping of the valley levee deposits and pelagic sedimentation seem to mark high stands of sea level during interglacial periods. Margin setting represents fan and/or source area  相似文献   

12.
The Rhone Fan is a large Plio-Pleistocene turbidite deposit in the western Mediterranean Sea. The fan is fed from the broad Rhone River delta, but only one canyon, the Petit-Rhone, has fed most of the major turbidite depositional sequences that have been mapped. Slumping of sediment from intercanyon areas on the delta slope also has provided much sediment for the fan. The lack of Recent turbidite deposition on the fan suggests that turbidite sedimentation dominates during glacial low stands of sea level, building major leveed valley sequences, while surficial slumping of the valley levee deposits and pelagic sedimentation seem to mark high stands of sea level during interglacial periods.  相似文献   

13.
Submarine fans and turbidite systems are important and sensitive features located offshore from river deltas that archive tectonic events, regional climate, sea level variations and erosional process. Very little is known about the sedimentary structure of the 1800 km long and 400 km wide Mozambique Fan, which is fed by the Zambezi and spreads out into the Mozambique Channel. New multichannel seismic profiles in the Mozambique Basin reveal multiple feeder systems of the upper fan that have been active concurrently or consecutively since Late Cretaceous. We identify two buried, ancient turbidite systems off Mozambique in addition to the previously known Zambezi-Channel system and another hypothesized active system. The oldest part of the upper fan, located north of the present-day mouth of the Zambezi, was active from Late Cretaceous to Eocene times. Regional uplift caused an increased sediment flux that continued until Eocene times, allowing the fan to migrate southwards under the influence of bottom currents. Following the mid-Oligocene marine regression, the Beira High Channel-levee complex fed the Mozambique Fan from the southwest until Miocene times, reworking sediments from the shelf and continental slope into the distal abyssal fan. Since the Miocene, sediments have bypassed the shelf and upper fan region through the Zambezi Valley system directly into the Zambezi Channel. The morphology of the turbidite system off Mozambique is strongly linked to onshore tectonic events and the variations in sea level and sediment flux.  相似文献   

14.
15.
A small Holocene fan is forming where Queen Inlet, a hanging valley, enters West Arm fjord, Glacier Bay, Alaska. Queen fan formed in the last 80 years following retreat of the Little Ice Age glacier that filled Glacier Bay about 200 yr BP. It was built mainly by a turbidite system originating from Carroll Glacier delta, as the delta formed in the early 1900s at the head of Queen Inlet. The Late Holocene Queen fan is comparable to large Pleistocene fans that formed in the Gulf of Alaska and differs from trough-mouth fans formed by cooler climate glacier systems. Received: 7 January 1999 / Revision received: 3 June 1999  相似文献   

16.
The Mississippi Fan is a large, mud-dominated submarine fan over 4 km thick, deposited in the deep Gulf of Mexico during the late Pliocene and Pleistocene. Analysis of 19,000 km of multifold seismic data defined 17 seismic sequences, each characterized by channel, levee, and associated overbank deposits, as well as mass transport deposits. At the base of nine sequences are a series of seismic facies consisting of mounded, hummocky, chaotic, and subparallel reflections, which constitute 10–20% of the sediments in each the sequences. These facies are externally mounded and occur in two general regions of the fan: (1) in the upper and middle fan they are elongate in shape and mimic the channel's distribution; (2) in the middle fan to lower fan they are characterized by a fan-shaped distribution, increasing in width downfan. These facies are interpreted to have formed as disorganized slides, debris flows, and turbidites (informally called “mass transport complexes”). Overlying this basal interval, characteristic of all sequences, are well-developed channel-levee systems that constitute 80–90% of the fan's sediments. Channels consist of high amplitude, subparallel reflections, whereas the flanking levee sediments appear as subparallel reflections that have high amplitudes at the base changing upward to low amplitude. The vertical change in amplitude may reflect a decrease in grain size and bed thicknesses. Overbank sediments are characterized by interbedded subparallel to hummocky and mounded reflections, suggesting both turbidites from the channel, as well as slides and debris flows derived both locally and from the slope updip.  相似文献   

17.
To help understand factors that influence submarine fan deposition, we outline some of the principal sedimentary, tectonic, and sea-level controls involved in deep-water sedimentation, give some data on the rates at which they operate, and evaluate their probable effects. Three depositional end-member systems, two submarine fan types (elongate and radial), and a third nonfan, slope-apron system result primarily from variations in sediment type and supply. Tectonic setting and local and global sea-level changes further modify the nature of fan growth, the distribution of facies, and the resulting vertical stratigraphic sequences. Margin setting represents fan and/or source area  相似文献   

18.
To help understand factors that influence submarine fan deposition, we outline some of the principal sedimentary, tectonic, and sea-level controls involved in deep-water sedimentation, give some data on the rates at which they operate, and evaluate their probable effects. Three depositional end-member systems, two submarine fan types (elongate and radial), and a third nonfan, slope-apron system result primarily from variations in sediment type and supply. Tectonic setting and local and global sea-level changes further modify the nature of fan growth, the distribution of facies, and the resulting vertical stratigraphic sequences.  相似文献   

19.
本次研究依据大量的钻井、露头和岩心资料,根据沉积构造、沉积层序特征及测井曲线对比分析,对姬塬地区延九段的沉积相进行研究,认为本区延九段为潮湿气候条件下的辫状河—辫状三角洲沉积,且明确了沉积相的时空展布和变化规律。研究区辫状三角洲平原上分流河道比较发育,还发育分流间、决口扇和沼泽沉积;三角洲前缘上主要发育水下分流河道和水下分流间。研究区储层砂体发育各种层理构造和侵蚀构造。河道砂坝储层物性好,常叠覆形成构造小高点,可形成构造-岩性油藏。  相似文献   

20.
以层序地层学为理论指导,通过对地震、钻井、测井及古生物等资料的研究,建立了北黄海盆地东部坳陷东南部的层序格架。研究区的中生界可分为1个一级层序、2个二级层序、5个三级层序,在此层序格架内进行了沉积相划分及沉积体系研究,厘定了扇三角洲、辫状河三角洲、浊积扇和湖泊沉积等4种沉积体系。断陷早期,JSQ1的西部与东部分别发育了中型的扇三角洲与辫状河三角洲沉积体系;断陷中期,西部的扇三角洲沉积体系逐步扩展并在其前端多发育小型浊积扇,东部的辫状河三角洲沉积体系亦持续扩张且在JSQ4沉积期规模达到最大;断陷晚期,KSQ1内仅发育盆缘的小型扇体和滨浅湖相沉积,东部、南部隆起区未接受沉积或沉积较薄并剥蚀殆尽。沉积体系的平面展布和纵向演化受古构造与古地貌的控制。  相似文献   

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