首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 250 毫秒
1.
红层,是指在侏罗纪、白垩纪干热气候条件下形成的以泥质和粉砂质岩石为主的岩层,因其呈红色而得名。  相似文献   

2.
在地质学中,红色岩石或称红层通常是指被少量细分散的铁的氧化物染成各种红色色调的沉积物或土壤残积物。红层在地球上分布广泛,它有不同的成因、不同的成分、含各种矿产,因此一向受到地质工作者的注意,并从不同角度得到调查。但是,红层中所含生物化石数量少,剖面往往不太稳定,又缺乏标志层,因此研究程度较低,这往往给区测人员造成困难。尽管如此,广大地质工作者还是对红层做了大量的研究工作,从不同角度对红层进行分类,研究红层的形成环境及成因,调查红层的古地磁,对红层的野外和室内研究进行总结。总  相似文献   

3.
在研究红层砂岩铜矿成矿规律和矿床成因的过程中,常会遇到构成岩石紫色和浅色的物质成分、岩石颜色的成因,以及其所代表的地质意义.通过几年的工作,我们把形成红层的紫色物质称为红铁尘.它分布广泛而普遍,在沉积成岩、成矿过程中具有很重要的意义;研究其地质过程有助于砂岩铜矿成因问题的解决和成矿规律的认识. 长期以来,人们都对红层的紫色给予一定的注意.在沉积矿物学、沉积岩石学和砂岩铜矿的研究中,认为形成红层的红色取决于其中所含的赤铁矿、褐铁矿和氢氧化铁等成分.例如,苏联普列奥勃拉任斯基等著的《沉积岩矿物》一书中指出:“形成于海底,含于盐矿层的红色夹层中;海成红色淤泥和粘土的红色取决于赤铁矿”.“杂  相似文献   

4.
我国南方红层的地质特征及其工程地质问题   总被引:1,自引:0,他引:1  
前言我国白垩纪至下第三纪的中新生代红层是岩石地层序列中最年轻的红色碎屑岩建造.在我国南方的广大地区都有分布,总出露面积达二十余万平方公里.浙赣及鄂西中新生代红层的累计厚度约2000~4000米,滇中地区自侏罗纪起始的红层总厚度达8000米以上.  相似文献   

5.
六苴砂岩铜矿是滇中中生代红层中的几种沉积铜矿床类型之一.滇中中生代红层为河湖交替相的沉积岩层,六苴矿床发育于白垩系马头山组红层所夹的浅色岩层中,而这浅色砂岩部分常具有明显的流动水沉积的特征.有关该矿床形成的岩相古地理分析,已有一些文章论述,这里试图结合野外观察和室内岩矿鉴定,着重从另一个侧面——岩石和矿石的胶结物方面,来讨论成矿作用,不妥之处,敬请指正.成矿作用和矿床形成后所经历的过程是一个复杂的过程.遵照毛主席关于抓主要矛盾的教导,我们认为六苴砂岩铜矿的岩石和矿石都是由碎屑和胶结物所组成,二者的区别主要不在于碎屑组分,而在于胶结物的组成.金属矿物就是岩石和矿石的胶结物成分之一,也由于金属矿物含量的差别而显示了岩石和矿石的不同,有时甚至是两者唯一的不同.因此,研究  相似文献   

6.
龙泉山地区中生代红层水岩作用时效性实验研究   总被引:1,自引:0,他引:1       下载免费PDF全文
龙泉山地区中生代红层分布广泛,水利工程较多,研究库区红层岩石水岩作用的时效性具有工程意义。通过对该地区4个水库采样点所采集的岩石样品进行室内软化系数的测定,得出红层岩石经库水长时间浸泡后软化系数及软化系数随年代的变化规律,结果显示红层经过30~50年水库浸泡后软化系数较目前在实验室测得的降低10%~20%。  相似文献   

7.
福建白垩纪红层主要分布于政和—大浦断裂带西侧,由于受不同时期、不同构造作用影响,各红层盆地发生、发展的时序及其岩石组合、生物群组合序列都不尽相同,本文根据红层盆地形成的构造背景及时序.将红层盆地分为三种类型:沙县—均口型、禾口—上杭型、连城—崇安型。其中,第一类型盆地形成于早白垩世中晚期,结束于晚白垩世最早期;第二类型盆地形成于早白垩世中晚期,结束于晚白垩世早期;第三类型盆地形成于晚白垩世;根据红层盐地岩石组合特征及序列,修订了原有地层单位的含义,将红层盆地岩石地层单位年历下而上划分为均口组、沙县组、禾口组、官寨组和赤石群。并详细论述了红层生物化石组合特征,建立了各门类化石组合序列。  相似文献   

8.
岩石模拟是岩土工程模型试验、地质岩芯模拟试验等研究的核心。但目前基于人工材料的模拟制备受限于现有相似理论与技术手段,成岩结果与实际岩性差异较大,特别是软岩的成型模拟问题尤为突出。以天然红层材料为原料,改进传统的成岩模拟系统,考虑成岩过程中温度、孔隙流体压力及上覆压力的分阶段影响,模拟红层软岩从松散岩土颗粒到岩石的形成过程,得到工程标准尺寸软岩岩芯。通过与天然红层软岩进行成岩过程、物理性质、化学性质及力学性质的对比研究表明,以天然红层为原料的软岩岩芯与天然红层软岩性质相似。该研究突破了人工材料配制、3D打印等方法一般只能满足某一方面性质的局限,为大量不同功能需求的软岩岩芯研究提供了新的制作思路与方法。  相似文献   

9.
为了研究福建省白垩纪红层形成的时代及构造背景,在政和-大埔断裂以西选取典型红层盆地,对不同盆地内火山岩夹层进行LA-ICP-MS锆石同位素定年和岩石地球化学分析.同位素U-Pb测年结果显示:沙县组的时限较长,为127~87 Ma,其总体时代应大致相当于晚白垩世早期,下部层段跨入早白垩世晚期;崇安组年龄为100.0±1.2 Ma,形成时代为晚白垩世早期.岩石地球化学结果表明,白垩纪红层中的火山岩为壳源成因,是处伸展环境下,为构造活动引起区域断陷拉张作用形成的一套钙碱性系列流纹岩.   相似文献   

10.
白垩纪大洋红层的致色机制及成因研究   总被引:2,自引:0,他引:2  
为了查明白垩纪大洋红层的致色矿物及其赋存状态,并探讨白垩纪大洋红层可能的制约因素及成因模式,本文以中国西藏床得剖面红色页岩、意大利Vispi Quarry剖面红色灰岩以及北大西洋ODP1049C孔12X岩芯段Aptian-Albian期高频旋回红色泥灰岩为研究对象,对各剖面(或岩芯)中的红色和非红色样品分别进行了X射线衍射和漫反射光谱测试,同时对配制的含赤铁矿的标样进行了同样的测试。测试结果表明,无论是红色页岩、红色灰岩,还是红色泥灰岩,赤铁矿都是主要的致色矿物,其中西藏床得剖面红色页岩由结晶较好的碎屑状赤铁矿和结晶较差的细分散状的赤铁矿共同致色。在意大利Vispi Quarry剖面红色泥岩中,结晶程度相近的赤铁矿是唯一的致色铁氧化物,而在ODP1049C孔红色泥灰岩中,结晶差的赤铁矿和针铁矿的出现是泥灰岩呈红色的矿物学根源。赤铁矿的形成主要受铁的来源、沉积时的氧化还原条件以及成岩作用的影响,这些因素也成为制约红层形成的关键因素。本课题组在多年研究的基础上,结合前人研究成果进一步从矿物学的角度深化了大洋红层的成因模式。  相似文献   

11.
中祁连木里盆地古近系ESR年龄及地质意义   总被引:1,自引:1,他引:0  
对中祁连木里盆地新生代红层进行ESR测年,获得了祁连山地区新生代红层沉积时代及构造变形年代学数据.研究表明,中祁连木里盆地内沉积了巨厚的新生代红层,较好地记录了祁连山隆升历史.盆地最老的新生代地层为始新世由湖相沉积组成的火烧沟组,ESR年龄为40.2~35.3 Ma,与上覆沉积时代为32.6~24.3 Ma的渐新世河湖相沉积组成的白杨河组呈角度不整合接触.构造变形特征与沉积环境的变化说明始新世末与渐新世初木里地区发生了构造变形和山脉的隆升,与祁连山地区新生代早期的隆升有很好的对应关系.  相似文献   

12.
Petroleum system theory has been used to study characteristics of the Fula depression in the Central African fault zone.In this system,deep lacustrine facies mudstone in the Abu Gabra For-mation of the Lower Cretaceous is a very good source rock,thick deltaic facies sandstone of the Abu Gabra Formation and fluvial facies sandstone of the Bentiu Formation are good reservoir beds,and the mudstone in the Upper Cretaceous Darfur Group is the regional cap rock.The oil search mode and fault block trap seal-off co...  相似文献   

13.
A sedimentary succession more than 5800 m thick, including the Lower Eocene to Lower Oligocene Fenghuoshan Group, the Lower Oligocene Yaxicuo Group, and the Lower Miocene Wudaoliang Group, is widely distributed in the Hoh Xil piggyback basin, the largest Cenozoic sedimentary basin in the hinterland of the Tibetan plateau. The strata of the Fenghuoshan and Yaxicuo groups have undergone strong deformation, whereas only minor tilting has occurred in the Wudaoliang Group. We analyze their sedimentary facies and depositional systems to help characterize continental collision and early uplift of the Tibetan plateau. The results indicate fluvial, lacustrine, and fan-delta facies for the Fenghuoshan Group, fluvial and lacustrine facies for the Yaxicuo Group, and lacustrine facies for the Wudaoliang Group. Development of the Hoh Xil basin underwent three stages: (1) the Fenghuoshan Group was deposited mainly in the Fenghuoshan-Hantaishan sub-basin between 56.0 and 31.8 Ma ago; (2) the Yaxicuo Group was deposited mainly in the Wudaoliang and Zhuolai Lake sub-basins between 31.8 and 30.0 Ma ago; and (3) the Wudaoliang Group was deposited throughout the entire Hoh Xil basin during the Early Miocene. The Fenghuoshan and Yaxicuo groups were deposited in piggyback basins during the Early Eocene to Early Oligocene, whereas the Wudaoliang Group was deposited in a relatively stable large lake. The Hoh Xil basin underwent two periods of strong north–south shortening, which could have been produced by the collision between India and Asia and the early uplift of the Tibetan plateau. The study suggests the Hoh Xil region could reach a high elevation during the Late Oligocene and the diachronous uplift history for the Tibetan plateau from east to west.  相似文献   

14.
通过对研究区露头、岩性、测井等特征的研究,将柴达木盆地新近纪上下油砂山组划分出5种重要的沉积相类型:冲积扇相、河流相、扇三角洲相、三角洲相、湖泊相,并进行详细描述。依据单因素分析多因素综合画图的方法论,做出上下油砂山组沉积相平面展布图。沉积相带是控制储层特征和分布的基本因素。结合沉积相带图,划出油砂山组储集相带,有利储集相主要是三角州前缘砂体,冲积扇-扇三角洲分流河道砂体,浅湖滩坝;主要分布在沙西、乌南、咸水泉、月牙山、红沟子、阿尔金斜坡带,而碱山地区的储集相带发育较差。  相似文献   

15.
辽宁北票四合屯盆地下白垩统义县组沉积相   总被引:5,自引:0,他引:5       下载免费PDF全文
本文系统地论述了北票四合屯盆地下白垩统义县组沉积时期的演化,将盆地演化划分为继承性初始坳陷、火山洼地、湖盆沉降与扩展三个阶段,其后由于火山作用而使盆地封闭。与盆地演化相对应,建立了盆内义县组的沉积相序,自下而上依次为冲积扇与河流相、火山沉积相、河流相、湖相(滨湖亚相,浅湖亚相,半深湖亚相,浅湖亚相,滨湖亚相,浅湖亚相)、火山溢流相,并指出火山喷发间歇期湖盆的湖水进退规律、水体性质以及沉积环境特征。  相似文献   

16.
鄂尔多斯盆地白垩系洛河组至环河华池组沉积相特征研究   总被引:1,自引:1,他引:0  
通过研究构造背景、野外露头、岩性组合、沉积构造、古生物特征和测井曲线特征,分析和总结鄂尔多斯盆地白垩系洛河组至环河华池组沉积相、相带分布范围和沉积特征。洛河组主要沉积了冲积扇相、风成沉积相、辫状河相和沙漠相;而在环河华池组主要沉积了湖相、三角洲相、曲流河相及风成砂岩夹层。平面上沉积相带的变化规律性较强,由盆地边缘的冲积相、冲积—河流相砾岩向盆内渐变为河流相—滨浅湖—半深湖相泥岩。沉积特征受构造运动影响和沉积相带控制,洛河组是从山缘向盆地内砂岩厚度迅速变薄、尖灭;环河华池组岩性变化表现为北粗南细、东粗西细,在北部砂体呈现东薄西厚,东北向西南增厚,在南部砂体呈近南北向展布,东薄西厚,南薄北厚。  相似文献   

17.
Sediments of the Upper Carboniferous to Lower Jurassic Karoo Supergroup (∼ 4.5 km thick) were deposited in the mid-Zambezi Valley Basin, southern Zambia. The Upper Palæozoic Lower Karoo Group in this area ends with a Late Permian sedimentary unit called the Madumabisa Mudstone Formation. The formation is 700 m thick and comprises four lithofacies grouped into two facies assemblages, collectively interpreted as lacustrine deposits. Sediments of a massive mudrock facies assemblage were deposited from suspension, probably from sediment-laden rivers entering a lake. Concretionary calcilutite beds probably mark the positions of palæosediment-water interfaces where calcite was precipitated. A laminated mudrock facies assemblage is attributed to lacustrine deposition from inflowing rivers at the lake margins and shallow parts of the lake. Repeated thickening-upward cycles are evidence of upward shallowing, interrupted by events of more abrupt deepening. Sandstone interbeds are interpreted as fluvial deposits laid down during low lake stands, with cross-lamination and asymmetrical ripples indicating current rather than wave deposition. A fossil assemblage of ostracods, bivalves, gastropods, fish scales, the alga Botryococcus sp. and fossil burrows is consistent with a lacustrine origin for the formation.  相似文献   

18.
北票—义县地区义县组岩石地层特征   总被引:6,自引:0,他引:6  
北票-义县地区的义县组地层是一套火山-沉积地层,其中火山岩地层占80%以上,具有四个火山作用亚旋回,第一亚旋回以基性-偏碱的基性-中基性火山作用为特征,第二亚旋回以中基性-酸性的火山作用为特征,第三亚旋回以基性-中性火山作用为特征,第四亚旋回以中酸性火山作用为特征;义县组火山-沉积地层包含至少7个沉积夹层,可以进一步归纳为四套沉积层,即底砾岩层、下部火山岩中的沉积夹层、中部湖相沉积层和上部河湖相沉积层,沉积层中生物化石主要集中在3个主要层位.综合火山岩的旋回性特征,岩石组合、岩石产出特征,不同岩石组合的上、下接触关系和岩石形成环境的分析结果,结合同位素年代学及生物地层学的研究成果,区内义县组被划分成了4个岩性段.同位素年龄数据显示义县组时代为早白垩世,其形成年龄介于135~120Ma之间,含中华龙鸟、孔子鸟和辽宁古果等珍稀化石的湖相沉积层是在125~127Ma之间形成的.  相似文献   

19.
本文以岩石学及沉积学为理论指导,以孤南30井沙三段的岩心、钻井、测井、录井、试油等资料为基础,对孤南30井沙河街组沙三段岩石地层的划分展开了研究,并寻找其有利储集层。研究表明:孤南30井沙河街组沙三段主要发育河流和湖泊两种类型沉积相,可分为4个砂层组,10个小层;沙三段中下部沉积水体较深,泥岩与砂岩互层,砂体含量增高,有利于形成良好的储集层,又发育有厚层灰质油泥岩,形成了较好的生储盖圈闭。  相似文献   

20.
Abstract

The Xihu sag, which is the largest petroliferous sub-basin of the East China Sea Shelf Basin, formed in a continental back-arc setting. The Oligocene Huagang Formation consisting of a fluvial–lacustrine succession deposited during the compressional stage is the prime hydrocarbon-bearing interval in the Xihu sag. A third-order sequence-stratigraphic framework has been built, and component sand-body characteristics were investigated based on seismic attribute analysis and well-log correlation. Two overall upward-fining sequences, and an internal low-accommodation systems tract (LAST) (fluvial successions characterised by amalgamated fluvial channel sand bodies interlayered with rare overbank deposits) and high-accommodation systems tract (HAST) (intervals dominated by overbank or lacustrine deposits) have been identified. The thick, multi-storied channel-fill sandstone bodies deposited along the central depression belt, capped by extensive overbank or lacustrine mud deposits, characterise each sequence and form favourable reservoir–seal associations. Proximal-to-distal changes in lithofacies associations were also analysed. The sequence-stratigraphic and lithofacies analysis suggest the existence of an axial, large-scale river channel system in the Oligocene Xihu sag. On the basis of the restoration of basin geomorphology and seismic facies analysis, the depositional architectures of the axial paleodrainage system have been reconstructed. Overall, the Huagang sequences represent the sedimentary evolution of a large-scale fluvial system sourced from axial and lateral supply areas, to form river deltas into an interior-draining basin-centre lake. Two major fluvio-lacustrine transgression–regression cycles have been recorded. During the transgression cycle, the fluvial morphology was dominated by braided fluvial style; whereas during the regression cycle, the fluvial morphology was characterised by a combination of multiple fluvial channel styles in the LAST, from upstream to downstream low-sinuosity braided, high-sinuosity braided and anastomosing fluvial channel patterns were distributed and then replaced by large-scale lake flooding in the HAST. The braided channel centre, paleobathymetric lows of channel networks and delta-front bodies are sand-prone units. The fluvial sedimentation was governed by multiple parameters: tectonics, paleogeomorphology and climate fluctuations. This integrated study on fluvial sedimentation and evolution of the Oligocene drainage system enable us to propose a conceptual model depicting fluvial channel styles and component sand-body architecture in lacustrine rift basins with axial plus transverse sediment supplies. This model can serve as a reference to illustrate channel-sand-body and associated reservoir architecture in similar types of drainage systems in terrestrial basins.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号