福建宁化早二叠世早期的小有孔虫动物群

本文报道的福建宁化湖村早二叠世时期与StaffellaTing共生的小有孔虫动物群,在福建地区还属首次发现。该动物群计有9属20种,称为Globivalvulina-Nodosaria组合。这一小有孔虫动物群的发现,不但为福建地区栖霞组底部补充了新的化石门类,且为石炭系二叠系的划分提供了新的依据。     

湘东南栖霞组底部石炭-二叠纪有孔虫混生动物群的发现

首次报道湖南省邵东保和堂柳东地区栖霞组底部与史塔夫（Staffella)Ting类群共生的丰富的小有孔虫动物群,包括19属、62种,其中新种2个,该动物群具有非常典型的石炭－二叠纪有孔虫群的混生特点,称Bradyina-Geinitzina组合,它标志着“隆林阶”在湖南地区的首次发现。     

桂西南柳桥地区二叠纪末期浅水相小有孔虫动物群

本文研究了广西扶绥县柳桥地区二叠纪末期的浅水相小有孔虫动物群。该动物群赋存于硅质岩相地层中的灰岩夹层里。动物群丰度和分异度均较高,共发现12属25种。其中包括长兴期的常见分子如Glomospira,No-dosaria,Colaniella等。此有孔虫组合与Colaniella组合大致相当,可以与类Paleofusulina带和Gallowayiella带相对比。     

山东济宁煤田东区太原组Ting类动物群

通过对山东济宁煤田东区太原组Ting类动物群的系统研究,共鉴定出Ting类化石15属108种。根据Ting类化石在地层中的分布和垂向的变化规律,自上而下建立一个Ting带三个亚带：Pseudoschwagerina带,3）Boultoniawillsi-Schwagerina cervicalis亚带,2）Pseudofusulina sphaeroidea-Schwagerina neolata亚带,1）Rugosofusulina complicata-Quasifusulina longissima 亚带。通过与邻区及华北部分地区对比,本区太原组Ting类动物群的地质时代为早二叠世早期,本区石炭－二叠系应置于太原组第十一层灰岩之底。     

福建武平中二叠统童子岩组的小有孔虫

本文首次报道福建武平地区中二叠统童子岩组中与复通道Ｔｉｎ（Ｐｏｌｙｄｉｅｘｏｄｉｎａ）群共生的小有孔虫动物群１８属４４种,其中新种３个,该动物群在国内很少报道。通过这一小有孔虫群的研究,为童子岩组的地层时代时属提供了又一佐证,对该地区童子岩组中的炭岩层古生态特征也作了简单的讨论。     

河南禹县晚古生代小有孔虫动物群

本文所研究的有孔虫标本取自河南禹县朱屯组所含8层灰岩中。计16属35种,其中2新种。自下而上分为3个有孔虫组合:1.Bradyina-Palaeotextularia angusta elongata组合(组合Ⅰ),2.Endothyra devexa-Palaeotextularidae(组合Ⅱ),3.Geinitzina postcarbonica组合(组合Ⅲ)。 根据有孔虫组合分析,朱屯组的时代为晚石炭世至早二叠世。确切的界线还有待于进一步研究。3个小有孔虫组合在华北地台上其它地区的同期沉积中亦可识别。因此可以期望它们在确定石炭二叠纪界限时发挥一定作用。     

黔西水城晚二叠世长兴期钙藻和有孔虫及其古环境意义

在黔西水城地区的K576井长兴组共鉴定钙藻3属3种,包括Gymnocodium bellerophontis、Permocalculus sp.和Tauridiumkurdistanensis;有孔虫8属10种,其中(虫筳)类2属2种,有孔虫动物群主要由Reichelinasp.indet.、Nankinella sp.、Pachyphloia schwageri、Pachyphloia sp.、Geinitzina sp.、Nestellorella sp. indet.、Howchinella sp.、Hemigordius aff. saranensis、Hemigordius sp.和Midiella sp. indet.组成。将本井按照生物特征分为有孔虫-钙藻-介形虫组合、有孔虫-腕足类-介形虫组合、介形虫-双壳类-腹足类组合、有孔虫-钙藻-双壳类组合、有孔虫-腕足类-介形虫组合、有孔虫-钙藻-双壳类组合和介形虫组合等7个组合。按照层序地层划分、垂向沉积序列特征和测井资料的分析,有孔虫-钙藻-介形虫组合(SQ3-3)和有孔虫-腕足类-介形虫组合(SQ3-4)时期地层为三角洲前...     

湖北京山早三叠世有孔虫动物群的发现及其意义

本文首次报道了湖北京山地区早三叠世有孔虫动物群,计６属１５种,其中包括４新种,在对该动物群分析基础上,作者建立了Ａｕｌｏｔｏｒｔｕｓｃｈｉａｌｉｎｇｃｈｉａｎｇｅｎｓｉｓ－Ｄｉｃｈｏｓｐｉｒａｓｉｎｅｎｓｉｓ组合带,通过对其古生态特征及生物相研究,揭示了该动物群的生活习性与生态环境的关系,简述了该有孔虫动物群的发现在地层划分对比及油气勘探中的意义。     

试用综合方法分析湖北省大峡口栖霞阶小有孔虫古生态

迄今为止,关于古生代小有孔虫生态研究的报道甚少。因此,以某些生态意义已经明确的典型属种为依据去识别小有孔虫的生活环境暂时还很困难,需要从其它角度去探讨这个问题。本文采用了结合其它学科的综合性研究方法,对湖北省兴山县大峡口栖霞阶小有孔虫动物群生态进行了分析:借助近代碳酸盐岩石学的研究成果,通过数理统计学手段,得到了与三种碳酸盐岩微相环境相对应的三个特征十分明显的小有孔虫生态组     

从有孔虫动物群论华南泥盆-石炭系之分界

本文研究了华南地区法门阶至杜内阶有孔虫动物群,并由下而上建立了五个有孔虫化石组合带(Ⅰ—Ⅴ),它们分布在黔南尧梭组上部(Ⅰ),者王组(Ⅱ),革老河组(Ⅲ),汤耙沟组下部(Ⅳ)和汤耙沟组中部(Ⅴ);在湘中则见于邵东组(Ⅱ),孟公坳组(Ⅲ),刘家塘组下部(Ⅳ)和刘家塘组中部(Ⅴ)。根据有孔虫动物群的分析,以及与西欧狄南盆地和苏联一些地区相当层位中有孔虫组合的对比,笔者认为以组合带Ⅲ之顶界作为泥盆-石炭系的分界。在黔南泥盆-石炭系的界线置于革老河组之顶;在湘中则位于孟公坳组之顶。因此,革老河组或孟公坳组属法门阶上部,改变了我国华南地区将这一界线置于邵东组之底或革老河组(包括者王组)之底的传统划法。     

山东兖州煤田太原组(竹蜓)类动物群及石炭-二叠系界线探讨

通过对山东兖州煤田太原组类动物群的系统研究,共鉴定出类化石12属103种及部分未定种。根据类化石在地层中的分布和垂向变化规律,自上而下建立一个带三个亚带:Schwagerina带:3)Triticitesparvus-Quasifusulinalongissima亚带,2)Schwagerinagregaria-Boultoniawillsi亚带,1)Quasifusulinapseudocayeuxi-Rugosofusulinavalida亚带。通过与邻区及华北部分地区对比,本区太原组类动物群的地质时代为早二叠世早期,本区石炭-二叠系界线应置于太原组第十一层灰岩之底。     

豫淮盆地太原组顶部斯威特刺(Sweetognathus)种的分类修正及其地层意义

作者通过对豫淮盆地太原组顶部灰岩中牙形刺的研究,发现Sweetognathus动物群较为丰富,计4属10种,含一个新种:Sweetognathuspraeiranicussp.nov.。其中以Sweetognathus最为繁盛,并对其种的分类进行了修正,将原定的Sweetognathusinornatus的大部分标本归入Sweetognathusmerrilli。根据新的分类,建立了两个组合带,即Sweetognathusmerrilli带和Sweetognathuswhitei-Xuzhougnathusmonoridgosus带。通过与国内外相当牙形刺组合带(带)的对比,初步认为该动物群属中、晚萨克马尔到早亚丁斯克期。     

青海省南部治多-杂多一带早石炭世有孔虫动物群

在青海省南部的治多—杂多一带1／25万地质填图中，于杂多群中首次发现非筵有孔虫，建立2个组合，即Endothyra-Mediocris—Archaediscus组合和Bradyina-Endothyranopsis组合，地质时代为早石炭世大塘期德坞期，与华南、塔里木盆地、西秦岭、前苏联等地同期生物群可很好地对比，同时结合大冢相似系数的计算表明，青海南部地区在早石炭世属于特提斯大区华夏生物区华南省。     

福建漳平下二叠统的小有孔虫

福建漳平岭兜下二叠统地层发育良好,序列清楚,与ting类共生的小有孔虫化石丰富。根据化石群垂直分布特点,可分为三个小有孔虫组合,自下而上为Geintzina-Pachyphloia组合,Langella-Pseudoglandulina longa组合及Hemigordius qinglongensis-Cribrogenerina celebrata组合。这三个小有孔虫组合在福建均属首次发现。这发现为下二叠统的地层时代归属又提供一佐证。     

Biostratigraphy and paleoecology of the Oligo-Miocene succession in Fars and Khuzestan areas (Zagros Basin,SW Iran)

Paleontological and biostratigraphical studies on carbonate platform succession from southwest Iran documented a great diversity of shallow-water benthic foraminifera during the Oligocene–Miocene. Larger foraminifera are the main means for the stratigraphic zonation of carbonate sediments. The distributions of larger benthic foraminifera in two outcrop sections (Abolhayat and Lali) in the Zagros Basin, Iran, are used to determine the age of the Asmari Formation. Four assemblage zones have been recognized by distribution of the larger benthic foraminifera in the study areas. Assemblage 3 (Aquitanian age) and 4 (Burdigalian age) have not been recognized in the Abolhayat section (Fars area), due to sea-level fall. The end Chattian sea-level fall restricted marine deposition in the Abolhayat section and Asmari Formation replaced laterally by the Gachsaran Formation. This suggests that the Miocene part of the formation as recognized in the Lali section (Khuzestan area) of the Zagros foreland basin is not present in the Abolhayat outcrop. The distribution of the Oligocene larger benthic foraminifera indicates that shallow marine carbonate sediments of the Asmari Formation at the study areas have been deposited in the photic zone of tropical to subtropical oceans. Based on analysis of larger benthic foraminiferal assemblages and microfacies features, three major depositional environments are identified. These include inner shelf, middle shelf and outer shelf. The inner shelf facies is characterized by wackestone–packstone, dominated by various taxa of imperforate foraminifera. The middle shelf is represented by packstone–grainstone to floatstone with a diverse assemblage of larger foraminifera with perforate wall. Basinwards is dominated by argillaceous wackestone characterized by planktonic foraminifera and large and flat nummulitidae and lepidocyclinidae. Planktonic foraminifera wackestone is the dominant facies in the outer shelf.     

黔南紫云四大寨长兴期小有孔虫

首次报道了产自贵州紫云四大寨剖面长兴期的有孔虫动物群,共计有9属22种,将此动物群与华南长兴期其它地区的有孔虫动物群进行了对比。     

云南保山地区二叠纪Shanita有孔虫动物群

系统研究了云南保山市卧牛寺附近大凹子组“破灰岩”中的Shanita有孔虫动物群,鉴定出其中特征分子Shanita和Hemigordiopsis8种(包括2新种,不含未定种和比较种),其他非有孔虫10属。研究结果表明,保山地区Shanita动物群的特征属和整体构成与缅甸、泰国和我国西藏等地的Shanita动物群相似,时代为茅口期晚期(冷坞期)至吴家坪期早期。但是,总体属级分异度较低,个别地方性种的出现及共生类的缺失,又使得保山地区的Shanita动物群具有一定的地域色彩。     

Benthic foraminiferal fauna during the time of the Indian-Asian contact, in southern Balochistan, Pakistan

Cretaceous and early Paleocene benthic foraminifera were studied from one section along the western Gaj River, southern Balochistan, Pakistan, to reconstruct the paleoenvironment of the Tethys Sea during the Indian-Asian contact. We recognize three lithostratigraphic units in ascending order: the Mughal Kot Formation, the Pab Sandstone, and the Jamburo Group. Both the Maastrichtian Mughal Kot Formation, which consists of shale with grey marly limestone, and the Maastrichtian Pab Sandstone, which consists of quartzose sandstone, indicate an open ocean environment as they have diversified planktic and benthic foraminiferal assemblages. The Maastrichtian-Paleocene Jamburo Group, consisting of dark grey, calcareous shale and marlstone with some sulfide grains, is characterized by low diversities of benthic assemblages. The change to the lower diversities may be associated with the development of poor circulation of deeper water that was caused by narrowing of the Tethys Sea.The Trochammina spp. Assemblage from the Jamburo Group, which can be correlated with flysch-type agglutinated foraminiferal assemblages, has a low benthic species diversity, indicating an unfavorable condition for calcareous foraminifera because of the development of oxygen-depleted water. The absolute abundance of agglutinated specimens shows a remarkable change from low numbers in the Maastrichtian to high ones in the Paleocene. The benthic foraminiferal evidence supports the hypothesis that the collision of the Asian and Indian plates occurred near the end of the Cretaceous.