青藏高原东部玉树隆宝蛇绿混杂岩中早二叠世放射虫的发现及其地质意义

报道了采自青藏高原东部玉树隆宝蛇绿混杂岩硅质岩岩块中的放射虫化石.该放射虫组合包括Latentifistula crux Nazarov et Ormiston,Pseudoalbaillella scalprata scalprata Holdsworth et Jones,Pseudoalbaillella scalprata rhombothoracata Ishiga,Pseudoalbaillella sakmarensis(Kozur)等.该放射虫组合属于Pseudoalbaillella scalprata rhombothoracata带,该带可以进行全球对比,地质时代为早二叠世.放射虫动物群与可可西里、滇西等地的古特提斯放射虫组合一致,它指示了玉树早二叠世存在深水沉积盆地.     

冲绳海槽南部表层沉积中的底栖有孔虫

研究了冲绳海槽南部33个表层样，共分析鉴定底栖有孔虫93属139种．建立了三个底栖有孔虫组合和两个亚组合：①Cibicidoidespraecincta-Pyngospp．组合；②Cibicidoides-Uvigerina组合：aCibicidoideswuellerstorfi亚组合，bHyalineabalthica-Buliminaaculeata亚组合；③Eggerella-Trochamminaglobigeriniformis组合．陆架坡折区以瓷质壳和螺旋壳类为主；大陆坡区的优势类群为瓶虫类、列式壳类和螺旋壳类；深海槽区主要为胶结质壳类和平旋壳类．水深500In以浅发育暖温和温水型有孔虫属种，可能是黑潮暖流影响结果；500m以深的深海、半深海低温属种占优势．月底栖有孔虫群确定的冲绳海槽南部地区溶跃面深度为1600m左右．     

冲绳海槽南部表层沉积物中放射虫的初步研究

通过对冲绳海槽南部４６个站位表层沉积物中的放射虫研究，初步鉴定９６个种，其中泡沫虫目在种和个休数量上均占绝对优势，与国内外有８在资料对照，冲绳海槽南部表层沉积物中放射虫组合属热带暖水动物群，根据定量统计资料，将表层沉积物中的放射虫分布四个分布区，探讨了沉积物类型，沉积物化学性质，海水温度，盐度，深度以及海流等地放射虫数量分布的影响。     

南郑梁山地区下古生界放射虫硅质岩的发现

1990年，在陕西省南郑县梁山地区下古生界上奥陶统和下志留统发现大量层状放射虫硅质岩。放射虫的外壳在薄片中呈圆形或椭圆形，直径一般在0．2mm左右，含量在15％－30％之间。研究表明，梁山地区的放射虫硅质岩形成于水体较安静的深水陆棚环境中，推测当时本区处于低纬度的大陆边缘洋流上升带。     

河南西峡湾潭地区二郎坪群微体化石研究

报道了河南省西峡县湾潭地区二郎坪群火神庙组硅质岩夹层中的牙形石类Ａｃｏｄｕｓｏｎｅｏｔｅｎｓｉｓ及放射虫类ＥｎｔａｃｔｉｎｉａｃｏｍｐｌａｌＩａｔａ，其时代应属早、中奥陶世；与其相邻的大庙组泥质板岩中发现的螺旋管状藻类化石及其管状微化石的组合面貌可与早寒武世小壳动物群对比。这些化石的发现为二郎坪群的时代归属提供了较为可信的证据。     

山东肥城煤田晚石炭世-早二叠世小有孔虫动物群

通过对肥城煤田晚石炭-早二叠世小有孔虫动物群的研究,共鉴定出小有孔虫化石25属73种。自上而下可建立三个小有孔虫组合：ⅢMultidiscustalimuensis-Glomospira-Palaeotextularia组合,ⅡTetrataxis-Nodosaria-Palaeotextularia组合,ⅠEotuberitina-Bradyina组合。通过与其它地区小有孔虫组合对比,肥城煤田这三个小有孔虫组合的时代应分别为晚石炭世晚期（组合Ⅰ）和早二叠世早期（组合Ⅱ和组合Ⅲ）。     

南京栖霞山大洼中二叠统栖霞组上升流沉积岩相组合类型

通过对南京栖霞山大洼中二叠统栖霞组上升流沉积岩相的观察,将其划分为燧石条带、硅质岩、硅质页岩和泥晶灰岩4种上升流岩相类型;并在剖面上呈有规律组合,共有3种组合形式。该3种岩相组合均属陆棚缓坡相,按水体深度,由浅至深,依次发育,构成了研究区陆棚斜坡沉积体系。缓斜坡带以含燧石条带泥晶生屑灰岩为特征,夹有暗色中薄层石灰岩、泥岩、页岩和硅质岩。     

对黔南桑朗石炭系深水沉积深度的探讨

桑朗石炭系以碳酸盐岩为主,如砂屑、生屑泥粒岩、海绵骨针粒泥岩和含放射虫灰泥岩,并夹海绵骨针硅质岩、层凝灰岩(?)、和白云岩等。它们形成韵律性沉积。在其正常的深水沉积中,有放射虫、硅质海绵骨针和浮游有孔虫等深水生物化石,而缺乏贝类等底栖动物群。浅水生物化石碎片只出现在浊积岩中。在所有的岩石中,均缺乏文石质壳的生物。根据现代深海和半深海的资料,其沉积深度应位于碳酸盐补偿面以上,文石补偿深度以下或其附近,水深500～600米以下的无氧环境。     

安徽南陵—铜陵地区茅口期碳酸盐孤立台地沉积特征分析

本文分析了安徽南陵-铜陵地区茅口期的沉积特征。描述和讨论的主要岩石类型有亮晶生物屑灰岩、泥晶海百合丘灰岩、含有机质藻粒泥晶灰岩、放射虫硅质岩及含钙质生物硅质岩。结合古生物和其它各种相标志,共划分出五个微相,即深水盆地、盆地边缘、碳酸盐缓坡、生屑浅滩和泻湖-潮坪相。研究区茅口期的沉积模式是一个被深水盆地包围的碳酸盐孤立台地。其地貌特征可与现代大巴哈马滩类比,所不同的是它发育了布满海百合灰泥丘的缓坡带。该孤立台地的沉积演化表现为向上变浅的海退序列。     

辽东湾表层沉积中有孔虫介形虫研究

对辽东湾的８８个表层沉积样品中的有孔虫介形虫进行了定性和定量分析，共得有孔虫４４属８７种，介形虫２４属３４种，按其分布范围的差异分为３个有孔虫介形虫组合；并探讨了组合与沉积环境的关系。     

影响沉积物中有孔虫丰度的死态因素探讨

根据近年野外调查和室内研究，本探讨了影响沉积物中有孔虫丰度值的诸死态因素，死态因素乃指环境对死亡后的生物体产生各种变化作用的自然因素。研究表明溶解作用和搬运作用对沉积中有孔虫丰度有极为重要的影响作用。     

苏皖地区孤峰组放射虫动物群及其古环境意义

苏皖地区下二叠统孤峰组４条剖面中含有极其丰富的放射虫化石，经鉴定计９属２７种，它们主要由阿尔拜虫类ａｌｂｉｌｌｅｌｌｉｄｓ，球形多囊虫类ｓｐｈｅｒｉｃａｌ ｐｏｌｙｃｙｓｔｉｎｅ和十字多囊虫类ｓｔａｕｒａｘｏｎ ｐｏｌｙｃｙｓｔｉｎｅ组成，并且可以划分成３个组合带，即Ｐｓｅｕｄｏａｌｂａｉｌｌｅｌｌａ ｆｕｓｉｆｏｒｍｉｓ－Ｐ．ｌｏｎｇｔａｎｅｎｓｉｓ，Ｆｏｌｌｉｃｕｃｕｌｌｕｓ ｍｏｎａｃａｎｔ     

Distribution,ecology, and oxygen and carbon isotope characteristics of modern planktonic foraminifers in the Makarov Basin of the Arctic Ocean

The Arctic region, with magnificent ice cover on the surface of the Arctic Ocean and adjacent seas, is not only extremely sensitive to but also has strong amplification effects on climate change. Observations during the past decades have documented substantial retreat and thinning of the Arctic sea-ice cover, a process that is accelerating. Its feedback and impact on the global climate has become an important subject of current climate change research. Calcite tests of planktonic foraminifers are major constituents in pelagic sediments, and they provide valuable materials for the reconstruction of past oceanographic conditions. However, research is still sparse in the Arctic sea area because of limited availability of the materials for investigation. Here, we present a study of modern foraminifers from the plankton tow samples taken in the Makarov Basin of the Arctic Ocean during the fourth Arctic expedition of China. We have analyzed ecological information stored in the modern planktonic foraminifers and in their stable isotope signals, and established a relationship between the distribution of the main taxa and the environment. Our main observations are as follows:(1) in the Makarov Basin, the polar species Neogloboquadrina pachyderma(sinistral coiling) dominates the [150 lm planktonic foraminiferal assemblages.(2) The planktonic foraminifers live mainly in the upper halocline at a water depth of 50–100 m and less in the depth interval of 100–200 m.(3) Temperature change in the halocline can affect the absolute abundance of planktonic foraminifers and their distribution in the water column. The warmer halocline is more favorable to the development of planktonic foraminifers.(4) A lighter d18O value(2.11 %) of N. pachyderma(sin.) is recorded in the depth interval of 100–200 m, which is likely related to the isotopically light brines separated out during sea ice freezing. The relatively heavy d18O value(1.68 %–2.68 %, average 2.27 %) in the depth interval of 50–100 m may be influenced by the low salinity water with the relatively heavy d18O value formed during the sea-ice melting in the surface layer.     

晚全新世以来长江口北支XL1孔有孔虫组合与气候、海平面变化研究

通过对长江口北支XL1孔48个样品的有孔虫定量分析,将该孔划分为3个有孔虫组合带（含有8个组合亚带）,并将其与崇明岛北部的永隆沙CY孔沉积特征进行对比,确定了XL1孔为晚全新世以来的沉积。对比分析两孔有孔虫组合特征,参照CY孔孢粉组合分析结果,对长江口北支XL1孔揭示的气候与海平面变化进行研究。XL1孔3个有孔虫组合带所反应的气候变化特征依次为温和略湿（后期又转暖一些）→温而略干→温暖湿润;海平面变化自带1→带3为上升-下降→下降-上升→上升的变化特征。     

Mesozoic Alpine facies deposition as a result of past latitudinal plate motion

The fragmentation of Pangaea as a consequence of the opening of the Atlantic Ocean is documented in the Alpine-Mediterranean region by the onset of widespread pelagic sedimentation. Shallow-water sediments were replaced by mainly pelagic limestones in the Early Jurassic period, radiolarian cherts in the Middle-Late Jurassic period, and again pelagic limestones in the Late Jurassic-Cretaceous period. During initial extension, basin subsidence below the carbonate compensation depth (CCD) is thought to have triggered the transition from Early Jurassic limestones to Middle-Late Jurassic radiolarites. It has been proposed that the transition from radiolarites to limestones in the Late Jurassic period was due to an increase in calcareous nannoplankton abundance when the CCD was depressed below the ocean floor. But in modern oceans, sediments below the CCD are not necessarily radiolaritic. Here we present palaeomagnetic samples from the Jurassic-Cretaceous pelagic succession exposed in the Lombardian basin, Italy. On the basis of an analysis of our palaeolatitudinal data in a broader palaeogeographic context, we propose an alternative explanation for the above facies tripartition. We suggest that the Lombardian basin drifted initially towards, and subsequently away from, a near-equatorial upwelling zone of high biosiliceous productivity. Our tectonic model for the genesis of radiolarites adds an essential horizontal plate motion component to explanations involving only vertical variations of CCD relative to the ocean floor. It may explain the deposition of radiolarites throughout the Mediterranean and Middle Eastern region during the Jurassic period.     

江苏北部岸外辐射沙洲有孔虫分布及其沉积环境分析

据定量分析,发现辐射沙洲海底表层沉积中有孔虫有９９种,５３属组成,这些有孔虫可划分为４个组合：Ａ．Ａｍｍｏｎｉａｂｅｃｃａｒｉｉ－Ｅｌｐｈｉｄｉｕｍｍａｇｅｌｌａｎｉｃｕｍ;Ｂ．Ａｍｍｏｎｉａｂｅｃｃａｒｉｉ－Ｐｒｏｔｅｌｐｈｉｄｉｕｍｇｌａｂｒｕｍ;Ｃ．Ａｍｍｏｎｉａｂｅｃｃａｒｉｉ－Ａ．ｐａｕｃｉｌｏｃｕｌａｔａ;Ｄ．Ａｍｍｏｎｉａｂｅｃｃａｒｉｉ－Ｅｐｉｓｔｏｍｉｎｅｌｌａｎａｒａｅｎｓｉｓ     

The characteristics and recognition of internal-tide and internal-wave deposits

Internal-tide and internal-wave deposits are a new and important type of deep-water traction-current deposits. Based on an analysis of documented internal-tide and internal-wave deposits, five facies types can be recognized: ( i ) bidirectional cross-laminated sandstone fades, ( ii ) unidirectional cross-bedded and cross-laminated sandstone facies, ( Ⅲ ) rhythmic alternating sandstone facies and mudstone, (iv ) flaser, wavy and lenticular bedded foraminiferal limestone facies, (v ) sandy oolitic limestone facies with flaser, wavy and lenticular bedding and epsilon cross bedding, which formed in submarine channel, unchannelized continental slope and plateau environments respectively. Accoding to the available data and knowledge, three sedimentation models are built; some discriminating characteristics of internal-tide and internal-wave deposits, and the distinction between them and contourites and turbidites are summed up.     

Molecular evidence for genetic mixing of Arctic and Antarctic subpolar populations of planktonic foraminifers

Bipolarity, the presence of a species in the high latitudes separated by a gap in distribution across the tropics, is a well-known pattern of global species distribution. But the question of whether bipolar species have evolved independently at the poles since the establishment of the cold-water provinces 16-8 million years ago, or if genes have been transferred across the tropics since that time, has not been addressed. Here we examine genetic variation in the small subunit ribosomal RNA gene of three bipolar planktonic foraminiferal morphospecies. We identify at least one identical genotype in all three morphospecies in both the Arctic and Antarctic subpolar provinces, indicating that trans-tropical gene flow must have occurred. Our genetic analysis also reveals that foraminiferal morphospecies can consist of a complex of genetic types. Such occurrences of genetically distinct populations within one morphospecies may affect the use of planktonic foraminifers as a palaeoceanographic proxy for climate change and necessitate a reassessment of the species concept for the group.     

番禺隆起新近系层序、沉积演化与地层圈闭

综合分析钻井、地震等资料,将区内新近系划分为14个三级层序,每个层序又可以海泛面为界细分为3～5个四级层序或体系域.层序界面和水进面与浮游有孔虫的丰度和分异度变化有密切关系.结合钻井约束的地震沉积学分析,可识别出低位域(辫状河)三角洲、河流三角洲、浅海陆棚等沉积体系.地层属性分析揭示了三角洲前缘沉积在平面上特有的环状结构.以四级层序为地层单元的沉积相平面编图可很好地反映不同体系域的沉积相演化.区内的层序结构和沉积相带演化主要受到海平面变化的控制.区内存在5种潜在的岩性地层或构造-地层圈闭,由断裂坡折带控制的低位域三角洲砂体已由勘探证实可形成重要的构造-地层油气藏.     

Carbon isotopic record of foraminifers in surface sediments from the South China Sea and its significance

Since the 1990s, the papers and data involved withthe South China Sea (SCS) have been emerging in largenumbers in the world as people pay more attention to thepaleoceanography of the SCS. There have been more than100 cores mentioned in papers containing p…