江西省晚白垩世周田组的再划分     

刘细元  衷存堤  张永忠  许连生  龙天 《华北地质》2004,27(4):217-222

江西自垩纪晚世地层中发育一套湖相细碎屑岩系，前人称之为周田组，一直沿用至今。作者认为前人对该岩石地层单位的定义不够准确或不够贴切。该组并不是“普遍含膏盐层”，而是仅在该组中部发育“膏盐层”，所以，有必要重新厘定；鉴于“膏盐层”的特殊性、且明显区别于组内其余部分岩性，因此，建议将该岩系新建为段级岩石地层单位——“会昌膏盐段”。这对当地乃至华南地区的陆相红盆的研究和地层划分对比、野外地质填图都具有重要意义，对寻找膏盐矿产资源也具有直接的指导作用。  相似文献   

Pelecinid wasps (Insecta, Hymenoptera, Proctotrupoidea) from the Cretaceous of Russia and Mongolia     

Haichun Zhang  A.P. Rasnitsyn   《Cretaceous Research》2004,25(6):807-825

Thirteen new species referable to four genera, of which one is new, from the Cretaceous of Russia and Mongolia are established herein and assigned to the family Pelecinidae. Among the four genera, Protopelecinus gen. nov., including four new species, is referred to the subfamily Pelecininae, while Iscopinus Kozlov, including three new species, Eopelecinus Zhang, Rasnitsyn and Zhang, including five new species, and Scorpiopelecinus laetus sp. nov. are assigned to the subfamily Iscopininae. Of these new taxa, eight, namely Protopelecinus regularis, P. furtivus, Iscopinus simplex, ?I. suspectus, Eopelecinus exquisitus, E. scorpioideus, E. rudis and Scorpiopelecinus laetus, are from the Lower Cretaceous Zaza Formation of Baissa, Transbaikalia, Russia; two, E. minutus and E. fragilis, are from the basal Lower Cretaceous Tsagan-Tsab Formation of Khutel-Khara, Mongolia; two, P. dubius and P. deformis, are from the Lower Cretaceous (Aptian?) of Bon Tsagan, Mongolia; and one, I. separatus, is from the Upper Cretaceous (Cenomanian) Ola Formation of Obeshchayushchiy, Russia. A key to fossil pelecinid wasps is provided and a morphological analysis shows that the Pelecinidae might be paraphyletic with respect to the Proctotrupidae. The Chinese insect fauna from both the Yixian and Laiyang formations is dominated by Eopelecinus and Sinopelecinus whereas the Siberian + Mongolian fauna from the Zaza and Tsagan-Tsab formations is dominated by Eopelecinus and Iscopinus. Hence, Eopelecinus is common to both. The differences between the two faunas are likely to be the result of geographical variation in populations.  相似文献   

Middle Campanian–lowermost Maastrichtian nannofossil and foraminiferal biostratigraphy of the northwestern Australian margin     

Robert J. Campbell  Richard W. Howe  John P. Rexilius   《Cretaceous Research》2004,25(6):827-864

The middle–late Campanian was marked by an increase in the bioprovinciality of calcareous microfossil assemblages into distinct Tethyan, Transitional, and Austral Provinces that persisted to the end of the Maastrichtian. The northwestern Australian margin belonged to the Transitional Province and the absence of key Tethyan marker species such as Radotruncana calcarata and Gansserina gansseri has led petroleum companies operating in the area to use the locally developed KCCM integrated calcareous microfossil zonation scheme. The KCCM zonation is a composite scheme comprising calcareous nannofossil (KCN), planktonic foraminiferal (KPF) and benthonic foraminiferal (KBF) zones. This paper presents the definitions and revisions of Zones KCCM8–19, from the highest occurrence (HO) of Aspidolithus parcus constrictus to the lowest occurrence (LO) of Ceratolithoides aculeus, and builds on our previous early–late Maastrichtian study. The presence of a middle–upper Campanian disconformity is confirmed by microfossil evidence from the Vulcan Sub-basin, Exmouth and Wombat plateaus, and the Southern Carnarvon Platform. In the Vulcan Sub-basin and on the Exmouth Plateau (ODP Hole 762C) the hiatus extends from slightly above the LO of common Rugoglobigerina rugosa to above the LO of Quadrum gothicum. On the Wombat Plateau (ODP Hole 761B) it spans from above the LO of Heterohelix semicostata to above the LO of Quadrum gothicum; and in the Southern Carnarvon Platform the disconformity has its longest duration from above the HO of Heterohelix semicostata to above the LO of Quadrum sissinghii. A significant revision of the events which define Zones KCCM18 and 19 was necessary owing to the observation that the LO of Ceratolithoides aculeus occurs below the HOs of Archaeoglobigerina cretacea and Stensioeina granulata incondita and the LO of common Rugoglobigerina rugosa. In the original zonation these events were considered to be coincident.  相似文献   

Revision of the conchostracan genera Cratostracus and Porostracus from Cretaceous deposits in north-east China     

Gang Li  David J. Batten   《Cretaceous Research》2004,25(6):919-926

The diagnoses of the conchostracan genera Cratostracus and Porostracus are revised following a re-examination of their type species under a scanning electron microscope. In Cratostracus each growth line has a serrated lower margin. Radial lirae branch into smaller ridges that merge with each other to give the upper part of each growth band in the ventral region of the carapace a slightly undulating surface. Cross-bars are present between these lirae. In Porostracus the radial lirae on the growth bands near the umbo are long and relatively widely spaced. There is a fine reticulum between them in the umbonal part of the carapace and cross-bars on the ventral surface. The ornament of Porostracus indicates that it can be assigned to the family Halysestheriidae rather than to the Afrograptidae, in which it has been placed previously. Morphological analysis of most of the species of the two genera and closely related Orthestheria (Migransia) under the scanning electron microscope is required before their stratigraphic potential can be fully realized.  相似文献   

Latest Jurassic–earliest Cretaceous radiolarian fauna from the Xialu chert in the Yarlung Zangbo suture zone, southern Tibet: Comparison with coeval western Pacific radiolarian faunas and paleoceanographic implications     

Atsushi  Matsuoka  Qun  Yang  Masahiko  Takei 《Island Arc》2005,14(4):338-345

Abstract The Xialu chert radiolarian fauna is latest Jurassic–earliest Cretaceous in age (Pseudodictyomitra carpatica zone) and contains many taxa in common with coeval northern hemisphere middle‐latitude (temperate) radiolarian faunas represented by the Torinosu fauna in southwest Japan. Common elements include Eucyrtidiellum pyramis (Aita), Protunuma japonicus Matsuoka & Yao, Sethocapsa pseudouterculus Aita, Sethocapsa (?) subcrassitestata Aita, Archaeodictyomitra minoensis (Mizutani), Stichocapsa praepulchella Hori and Xitus gifuensis (Mizutani). The Xialu fauna is less similar to low‐latitude (tropical) assemblages represented by the Mariana fauna. For this reason, the Xialu fauna is regarded as representative of a southern hemisphere middle‐latitude (temperate) fauna. A mirror‐image bi‐temperate provincialism to the equator in radiolarian faunas is reconstructed for the Ceno‐Tethys and Pacific Ocean in latest Jurassic–earliest Cretaceous time.  相似文献   

中国海相油气田勘探实例(之一) 四川盆地罗家寨大型气田的发现和探明   总被引：21，自引：4，他引：21  

冉隆辉  陈更生  徐仁芬 《海相油气地质》2005,10(1):43-47

罗家寨气田发现于2000年,是四川盆地迄今为止发现的储量规模最大的一个气田,2002年探明储量为581.08×108m3。其下三叠统飞仙关组储层由碳酸盐岩蒸发台地边缘优质鲕粒滩白云岩构成,圈闭面积大,构造幅度高,具有一定的埋藏隐蔽性。论述了气田的发现和探明过程,气藏地质的特征,以及对碳酸盐岩气藏勘探的启示。  相似文献   

准噶尔盆地腹部白垩系清水河组清一段高分辨率层序地层特征及岩性油气藏预测   总被引：1，自引：0，他引：1  

斯春松  王海东唐勇  沈金龙徐洋 《华东地质学院学报》2005,28(4):329-333

通过钻井、岩芯和测井等资料的分析，清水河组清一段划分出1个长期基准面旋回、2个中期基准面旋回和5个短期基准面旋回。MSC1中期基准面旋回主要为辫状河三角洲沉积，MSC2中期基准面旋回为湖泊相沉积，局部地区夹有辫状三角洲沉积，极易形成岩性油气藏。区域性隔层发育在非对称型长期基准面旋回的上部，有利的储集体主要分布于中期基准面上升的早期。  相似文献   

内蒙古大青山-乌拉山地区孔兹岩系的早期变质地层结构——下地壳近水平顺层滑脱变形的产物   总被引：4，自引：0，他引：4  

徐仲元刘正宏  杨振升 《地层学杂志》2005,29(11):423-432

近年来孔兹岩系作为高级变质岩区一套特征性的变质沉积岩石组合而受到广泛关注，但其变质地层结构及其相关的构造作用和构造样式还不为人所了解。通过对内蒙古大青山一乌拉山地区以孔兹岩系发育为特征的高级变质杂岩的研究发现，区内孔兹岩系自下而上由3个岩石地层单位组成：榴云片麻岩岩组、透辉片麻岩岩组和大理岩岩组，表现出由细碎屑沉积-碎屑沉积和钙质化学沉积的混合物-镁质碳酸盐组成的沉积旋回。这些变质地层不仅遭受到具有近等温降压顺时针P-T演化特征的麻粒岩相变质作用的改造，同时，还遭受到近水平顺层滑脱变形构造、穹-褶构造和近东西向陡倾叶理带这三种构造形式为主的多期变形的改造。由此，这些变质地层在空间上多以不规则条带状、不规则团块状或透镜状形式出露，同时，各地层单位在空间上具有“犬牙交错，参差产出”，“岩层缺失，隔层相触”的特征。研究结果表明，区内孔兹岩系目前的产出状态及“犬牙交错，参差产出”的特征是穹-褶构造尤其是近东西向陡倾叶理带叠加改造的结果，在消除其改造的影响后可以确定，由于近水平顺层滑脱变形改造的结果，这些变质地层发生“岩层缺失，隔层相触”，在空间上表现为以近水平的长轴近东西向的扁豆体堆叠而成的早期变质地层结构，这是高级变质地层所特有的变质地层结构。  相似文献   

Revision of the conchostracan genus Estherites from the Upper Cretaceous Nenjiang Formation of the Songliao Basin and its biogeographic significance in China     

Gang Li  David J. Batten   《Cretaceous Research》2005,26(6):920-929

The diagnosis of Estherites corrugatus from the basal part of the Coniacian Second Member of the Nenjiang Formation in Nenjiang County, north-east China is revised following the application of a new preparation technique to some of the carapaces and an examination of specimens under a scanning electron microscope, both of which revealed morphological features on the carapace that had not been recognized previously. Restudy of the type species of the two subgenera Estherites (Euestherites) and Estherites (Parestherites) also revealed details of carapace features not seen hitherto. These indicate that they should be separated from Estherites. As a result, Euestherites is upgraded to genus level and Parestherites is placed in synonymy. The importance of Estherites and Euestherites is considered in the context of Late Cretaceous assemblages of these crustaceans and the three conchostracan provinces (South-West, South-East and North China) that are recognized to have been present in China during the Turonian–Santonian period.  相似文献   

EXPLORATION ENGINEERING     

《Abstract of Chinese Geological Literature》2014,(3)

正20141864 Deng Mengchun(Institute of Exploration Technology,CAGS,Chengdu 611734,China);Huang Shenghui Rock Sample Collection and Division Technologies for Air Reverse Circulation Sampling Drilling(Exploration Engineering,ISSN1672-7428,CN11-5063/TD,40(7),2013,p.73-76,80,16 illus.,5 refs.)  相似文献