共查询到20条相似文献，搜索用时 109 毫秒
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粤北泥盆纪地层发育较全,分布广泛,矿产资源丰富。老虎头组顶部泥岩段ms及融县组顶部泥岩段删;是粤北地区新填绘出的泥盆纪非正式岩石地层单位。它们可分别与湖南省相应的地层（易家湾组及欧家冲组）进行对比。这些岩石地层常呈透镜状出露,在区域上分布不稳定（岩性岩相不定、厚薄不一,有时甚至可能尖灭）,但对粤北泥盆纪岩石地层划分有着重要作用,同时也是多金属矿的目标层,对找矿有着标志性意义。 相似文献
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关于甘肃长城纪地层划分的新认识 总被引：10，自引：0，他引：10
甘肃的长城纪地层划分以岩石地层为主。地层区可划分为北山地层区、祁连—北秦岭地层区（包括祁连山西段分区和兰州—天水分区）、华北地层区陇东分区及扬子地层区摩天岭分区。甘肃省长城纪岩石地层共分为７个群级单位（铅炉子沟群、古硐井群、朱龙关群、托来南山群、兴隆山群、碧口岩群、贺兰山群）、７个组级单位（熬油沟组、桦树沟组、南白水河组、葫芦河组、阳坝岩组、秧田坝岩组、黄旗口组）和６个组级非正式岩石地层单位。各单位特征明显，反映了甘肃省长城纪古地理轮廓和地层格架面貌 相似文献
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王成文 《吉林大学学报(地球科学版)》1998,(2)
在概要地讨论了辽河岩群基本地层学特征基础上,提出了构造变质岩石地层的概念,其含义为经强烈构造变形的中浅变质沉积（含火山沉积）岩系构成的岩石地层单位的一种类型。构造变质岩石地层单位是强变形、中浅变质沉积岩区１∶５万填图的基本填图单位。建议采用岩群、岩组、岩段等地层单位命名系统,强调了变形、变质、沉积综合研究方法。 相似文献
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本文研究了嵩箕地区山西组的４条剖面，提出了嵩箕地工山西组时代为早二叠世早期（山西组下段）至早二叠世晚期（山西段），认为山西组是三角洲环境下形成的，主要可采煤层二煤是三角洲平原上的沼泽沉积。文章指出了丰富的大羽羊齿植物和银杏类植物在豫西地区山西的出现，不是以植物迁移的时间差所能解释的，而是由于岩石地支单位穿时的结果，根据地层指志“组”的定义，本区山西组与邻区作岩性比较后认为，引用“山西组”这一名来命 相似文献
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广东泥盆纪岩石地层划分 总被引：1，自引：0，他引：1
广东泥盆系除奥东区全由碎屑岩组成外，粤西，粤北和粤中区均具有下部碎屑岩和上部碳酸盐岩、碎屑岩（或硅质岩）呈不等厚互层的二元结构，以碎屑岩与碳酸盐岩（或硅质岩）的分界为标志划分为１个群（桂头群）１３个组（杨溪组等）和５个段（石角咀段等）共１９个岩石地层单位，广东泥盆纪海水随时间的推移大致呈西一东方向进、退，形成的各岩石地层单位在区域延展中具有明显的穿时特征，沉积时间自西而东逐渐变晚。 相似文献
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山东九龙群炒米店组概念新议 总被引：1，自引：1，他引：0
山东地区寒武系-奥陶系界线以往是以三叶虫和角石生物带为依据来确定,由于在界线上下几十米难以获得这类可供鉴定的大化石,这一重要年代地层界线实际上就划在三山子组b段之底。在长清区崮山镇范庄剖面上该界线确定在炒米店组之顶界,因而山东炒米店组被定义为"上寒武统最上部的一个岩石地层单位"。近年来,在长清张夏—崮山地区、青州尧王山地区和莱芜黄羊山地区,根据牙形石"Cordylodus lindstromi"准确确定的寒武系-奥陶系界线均位于炒米店组内部,分别距炒米店组顶9.05m、58.10m和4.00m。根据上述成果和岩石地层单位命名原则,炒米店组应定义为跨寒武纪与奥陶纪的岩石地层单位。 相似文献
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从层序地层学角度论岩石地层单位界线的厘定与优化 总被引：7，自引：0，他引：7
以碳酸盐台地内部、边缘及盆地３个不同相区的岩石地层基本单位———组为实例,从层序地层学角度论述了岩石地层单位界线的厘定与优化方案,认为以层序（尤其是Ⅰ型层序）界面及体系域之间界面（即初始海泛面、最大海泛面等）作为一些组的新界线,将会更有利于野外岩石地层单位的识别与对比。 相似文献
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陆相火山岩区岩石地层划分的探讨 总被引：4，自引：2，他引：2
陆相火山岩区火山产物的旋回、岩相及韵律性是 火山 活动发生及演化阶段 性的反映,也是岩石地层划分应该兼顾的重要特征之一。岩石地层划分的依据是岩性岩相特 征,各岩石地层单位均有具体的岩性岩相内容,并有别于相邻的岩石地层单位。因此,陆相 火山岩区的岩石地层划分,在满足岩石地层划分要求的前提下,应把火山活动产物的自身特 点 作为重要的依据。若将岩石地层单位“群”与火山旋回、“组”与复合岩相、“段”与火山 岩相或沉积岩相、“层”与火山岩相的基本类型对应起来,可建立起岩石地层单位“群”与 火山活动阶段、“组”与火山构造演化阶段、“段”与火山活动期或间隙期、“层”与火山 作用 类型的直接联系,从而使岩石地层划分与火山活动的历史研究有机地结合起来。 相似文献
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R.J. Wyatt 《Proceedings of the Geologists' Association. Geologists' Association》2009,120(2-3):126-132
The type section of the Hampen Formation, as currently defined, is located near Salperton (Gloucestershire); it comprises beds of Middle Jurassic (Bathonian) age. Its validity as a type section is questioned; only the uppermost 2.3 m are herein considered truly to represent the Hampen Formation. The underlying 7.4 m are re-defined as a facies variant of the Througham Formation, for which the name Daglingworth Member is proposed. A review of the local stratigraphical context clarifies the relationship of the Hampen Formation, as newly defined, and of the Daglingworth Member, to contiguous stratigraphical units. 相似文献
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John C.W. Cope 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(1):89-91
The Geological Survey’s Framework Report on the Old Red Sandstone of the Anglo-Welsh region includes a proposal for a new formational name, the Cwmffrwd Formation, for the basal formation of the Daugleddau Group in Carmarthenshire, S. Wales.The name is preoccupied by the Early Ordovician Cwmffrwd Member of the Carmarthen Formation and a new name, the Green Castle Sandstone Formation is proposed for the Cwmffrwd Formation. 相似文献
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本文提出延边地层区的晚石炭世地层有两种类型：一是原地系统的天宝山组；二是外来岩块，包括原山秀岭组。并建议停止使用山秀岭组一名。 相似文献
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Joonas J. Virtasalo Jyrki Hämäläinen Aarno T. Kotilainen 《Boreas: An International Journal of Quaternary Research》2014,43(4):924-938
The Late Pleistocene and Holocene glacial and postglacial sediments of the Baltic Sea basin are conventionally classified into units according to the so‐called Baltic Sea stages: Baltic Ice Lake, Yoldia Sea, Ancylus Lake and Litorina Sea. The Baltic Sea stages have been identified in offshore sediment cores by fundamentally different criteria, precluding detailed comparisons of the sediment units amongst different sea areas and studies. Here, long sediment cores and reflection seismic and pinger sub‐bottom profiles were studied from an offshore area in the Gulf of Finland, northern Baltic Sea. The strata are divided on the basis of sedimentological criteria into three allostratigraphical formations with subordinate allostratigraphical members and lithostratigraphical formations, following the combined allostratigraphical and lithostratigraphical (CUAL) approach. Sedimentological features are recommended as the primary stratigraphical classification criteria because they do not require the palaeoenvironmental inferences of salinity and water level that are inherent in the conventional classification practice. The presented stratigraphical division is proposed as a flexible template for future stratigraphical work on the Baltic Sea basin, whereby lower‐rank allounits and lithounits can be included and removed locally, while the alloformations will remain at the highest hierarchical level and guarantee regional correlatability. The stratigraphical division is compatible with international guidelines, facilitating communication to the wider scientific community and comparison with other similar basins. 相似文献
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ALEKSIS DREIMANIS PHILIP GIBBARD 《Boreas: An International Journal of Quaternary Research》2005,34(2):101-122
The Catfish Creek Drift Formation is a significant and extensive lithostratigraphical marker unit in SW Ontario. Here the stratotype, exposed in the Lake Erie bluffs of the Plum Point-Bradtville (Grandview) area south of London, Ontario, Canada, is proposed. It consists of subglacial and proglacial sediments deposited at the beginning of the Nissouri Phase of the Wisconsinan glaciation. In the 2.5-km-long stratotype section, the Catfish Creek Drift consists of 9 members. Five of them, the Dunwich and Grandview I-IV members, mainly consist of till, with minor components of stratified drift. The Dunwich till was deposited by the Huron-Georgian Bay lobe, but the Grandview I-IV tills by the Erie lobe. The Zettler Farm Member consists of co-lobal till in the central part of the section and of a proglacial waterlain flow diamicton and a subglacial undermelt diamicton in the SW part. Three members consist entirely of stratified drift; the glaciolacustrine silty and clayey Waite Farm Member, the ice-marginal deltaic Oosprink Farm Member and the Boy Scout Camp Member - deposited by meltwater streams in subglacial channels. The sequence of interbedded till and stratified drift represents the oscillating advance of the Laurentide Ice Sheet in the Lake Erie basin. 相似文献
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Sequence stratigraphical analysis was applied to the Upper Carboniferous–Lower Permian sedimentary succession of the northeastern Ordos Basin, north China based on data acquired from ten entire logging curves and eight outcrops. The facies framework of the lithostratigraphical unit, the Taiyuan Formation comprises seven facies in two facies associations, varying from fluvio-delta to shelf-barrier islands. The facies are presented within a chronostratigraphical framework, linked by systems tract, which in turn are limited by flooding surfaces and sequence boundaries. Six third-order depositional sequences are recognised, bounded by six type 2 unconformities. An upwards-shallowing epicontinental sea sedimentary model is created, which consists of a sandstone, coal seam and carbonate succession. 相似文献
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萨拉乌苏河流域第四系岩石地层及其时间界限 总被引：21，自引：0，他引：21
根据对位于鄂尔多斯高原毛乌素沙漠东南部边缘萨拉乌苏河流域的米浪沟湾剖面岩石地层划分并结合年代测试结果,提出了如下一些看法1以组为代表的岩石地层单元的形成时间为离石组>150000aB.P.、萨拉乌苏组150000-75000aB.P.、城川组75000-10000aB.P.、大沟湾组-滴哨沟湾组10000-1000aB.P.、范家沟湾组1000aB.P.-现代.2以上岩石单元与黄土高原相同时期层系具有较好的对比关系离石组\萨拉乌苏组、萨拉乌苏组\城川组和城川组\大沟湾组在地质时代上依次与L2\S1(时限为140000aB.P.)、S1\L1(时限为80000aB.P.)和L1\S0(时限为11000-10000aB.P.)大体是等时的.3如以过去全球变化而论,则目前已经可以确切地将米浪沟湾剖面诸岩石单元与深海和大陆冰川最近地质时期的若干氧同位素阶段进行对比,以“”表示为离石组MIS6、萨拉乌苏组MIS5、城川组MIS2～MIS4、大沟湾组+滴哨沟湾组+范家沟湾组MIS1.显然,这一对比关系清楚地说明,我国沙漠万年时间尺度环境演变,与黄土的研究结果一样,在很大程度上受到北半球冰期间冰期气候波动的影响.据此,可以按气候地层进行划分,将离石组、萨拉乌苏组、城川组、大沟湾组+滴哨沟湾组+范家沟湾组的时代分别置于里斯冰期、里斯-玉木间冰期(末次间冰期)、玉木冰期(末次冰期)和冰后期。 相似文献
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四川天全、芦山、宝兴地区名山组地层特征 总被引：1，自引：0，他引：1
下第三系名山组广泛分布于天全-芦山复向斜内,地层出露良好。笔者(1989—1991年)在参加1:5万天全幅、灵关幅区域地质调查时,根据岩组图填图要求,又进一步展开了对名山组的研究。本文简要地介绍了新实测的地层剖面,以及重新将名山组划分为4个段和新建大溪砾岩等填图单元的情况;并阐述了将芦山组归并于名山组上部(4段)而取消该组名称的依据。综述了研究区的岩石组合特征、沉积构造,建立了地层层序。将名山组沉积环境解释为辫状河及湖泊环境。 相似文献
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The stratigraphical occurrence of 35 known species from the Upper Cretaceous and Danian of Southern Limburg is presented based on existing collections and newly collected material. Corals are relatively rare, except in the Meerssen Member of the Maastricht Formation. Two faunas were recognised in the Meerssen Member: a fauna dominated by Cyclolites cancellata at the base of this member – which coincides with the sequence boundary of the third-order sequence cycle TA1.1 of Haq et al. (1988) – and a fauna dominated by mushroom-shaped and encrusting colonies at the top of the transgressive systems tract of the same sequence cycle. 相似文献