广西桂林泥盆纪礁组合中的层层问题

广西桂林的泥盆系包含艾菲尔期（包括少部分吉维期）的碎屑岩和吉维期至法门期的碳酸盐岩。以碳酸盐沉积发育期的５个实测剖面为基础，并结合牙形刺生物地层和不同沉积单元的微相研究探讨碳酸盐合地礁组合沉积的地层问题。根据牙形刺Ｉｃｒｉｏｄｕｓ和Ｐｄｙｇｎａｔｈｕｓ的组合特征提出广布于桂东北的信都组的顶界约相当于ｖａｒｃｕｓ带的底界；根据礁前斜坡相和台内浅水相沉积中的牙形刺，四射珊瑚及腕足类的组合特征，认为台内     

从综合地层学观点论华南浅海相泥盆系—石炭系的分界

生物地层学、事件地层学和层地层学综合研究表明，华南浅海相区与Ｓｉｐｈｏｎｏｄｅｌｌａｐｒａｅｓｕｌｃａｔａ带和Ｓ．ｓｕｌｃａｔａ带之间的界线相当的泥盆系－石炭系的界线不仅高于Ｃｙｓｔｏｐｈｒｅｎｔｉｓ带楔界，而且还应高于引起Ｃｙｓｔｏｐｈｒｅｎｔｉｓ绝灭的海退事件层的顶界。     

华南上泥盆统和下石炭统层序地层学

本文把华南法门阶上部和杜内阶分为４个层序，自下而上依次命名为ＳＱ０、ＳＱ１、ＳＱ２和ＳＱ３。其中ＳＱ０属斯图年阶（Ｓｔｒｕｎｉａｎ）（泥盆系最顶部），其余３个层序归杜内阶。这４个层序可以与欧美等地同期的层序进行对比，表明当时的海平面升降变化及其由此而产生的沉积层序具有全球的一致性。层序地层学、生物地层学和事件地层学综合研究表明，华南浅海相区与Ｓｉｐｈｏｎｏｄｅｌａｐｒａｅｓｕｌｃａｔａ－Ｓ．ｓｕｌｃａｔａ界线一致的泥盆－石炭系界线不仅高于Ｃｙｓｔｏｐｈｒｅｎｔｉｓ带顶界，而且还应高于引起Ｃｙｓｔｏｐｈｒｅｎｔｉｓ绝灭的海退事件层的顶界。因此建议以Ｃｙｓｔｏｐｈｒｅｎｔｉｓ－Ｐｓｅｕｄｏｕｒａｌｉｎａ间隔带中最明显的一个海进面，即ＳＱ１的海进体系域的底界作为华南浅海相区泥盆－石炭系界线。这条界线与泥盆－石炭纪之交海退事件层的顶界正好一致，大致相当于Ｐｓｅｕｄｏｕｒａｌｉｎａ组合带底部。     

华南泥盆纪海平面弯化节律及圈层耦合关系

在加里东不整合面之上的华南纪盆系中，可识别出２０个正层序和相对应的海平面变化旋回，其中下泥盆统９个，中泥盆弦５．５个，上泥盆统５．５个。它们可归并为４个正层序组，最大海泛面分别位于ｓｕｌｃａｔｕｓ带，ｐｅｒｂｏｎｕｓ带（Ｄ＾３１），中、上ｖａｒｃｕｓ带（Ｄ＾２２）和ｇｉｇａｓ带。     

桂西北早,中二叠世常么期和栖霞期含Ting地层及分带

桂西北早期二叠世常么期和栖霞期地层为一套浅海碳酸盐碉相连续沉积,其中Ｔｉ类化石十分丰富,自下而上可划分为５个化石带,４个亚带：１）Ｐａｍｉｒｉｎａ－Ｓｃｈｗａｇｅｒｉｎａ带（Ｐａｍｉｒｉｎａ ｐｕｌｃｈｒａ亚带;Ｓｃｈｗａｇｅｒｉｎａ ｃｕｓｈｍａｎｉ亚带）;２）Ｓｃｈｗａｇｅｒｉｎａ ｇｕｅｍｂｅｌｉ带;３）Ｃｈａｌａｒｏｓｃｈｗａｇｅｒｉｎａ－Ｒｏｂｕｓｔｏｓｃｈｗａｇｅｒｉｎａ带（Ｃｈａｌａ     

皖西贵池、宿松地区中下三叠统沉积环境及层序分析

摘要：皖西中、下三叠统为一套碳酸盐岩沉积。从下往上,其沉积环境经历了从盆地－开阔陆棚－开阔台地－局限台地－潮上蒸发台地这样一个海水逐渐变浅、盐度不断增高的环境演化序列．据露头剖面分析,这套碳酸盐岩地层可分成３个层序。层序均由低水位、海进和高水位体系域组成,特征明显。据其岩性特征及准层序的叠置方式,识别出了追赶碳酸盐体系（ｃａｔｃｈｕｐｃａｒｂｏｎａｔｅｓｙｓｔｅｍ）和并进碳酸盐体系（ｋｅｅｐｕｐｃａｒｂｏｎａｔｅｓｙｓｔｅｍ）。     

泥河湾地区晚新生代生物地层带

本文根据岩石地层，哺乳动物化石及古地磁资料的综合分析研究，将泥河湾地区晚新生代生物地层划分为５个生物地层时限带，并推算出每个带的年限，它们是：（１）Ｈｉｐｐａｒｉｏｎ ｈｏｕｆｅｎｅｎｓｅ时限带，？－３．３０Ｍａ；（２）Ｍｉｍｏｍｙｓ ｏｒｉｅｎｔａｌｉｓ时限带，３．３０－２．４８Ｍａ；（３）Ｍｉｍｏｍｙｓ ｙｏｕｈｅｎｉｃｕｓ时限带，２．４８－１．８７Ｍａ；（４）Ａｌｌｏｐｈａｉｎｏｙｓ ｃｆ．     

桂西北早、中二叠世常么期和栖霞期含地层及分带

桂西北早中二叠世常么期和栖霞期地层为一套浅海碳酸盐岩相连续沉积,其中类化石十分丰富,自下而上可划分为５个化石带、４个亚带：１）Ｐａｍｉｒｉｎａ－Ｓｃｈｗａｇｅｒｉｎａ带（Ｐａｍｉｒｉｎａｐｕｌｃｈｒａ亚带;Ｓｃｈｗａｇｅｒｉｎａｃｕｓｈｍａｎｉ亚带）;２）Ｓｃｈｗａｇｅｒｉｎａｇｕｅｍｂｅｌｉ带;３）Ｃｈａｌａｒｏｓｃｈｗａｇｅｒｉ－ｎａ－Ｒｏｂｕｓｔｏｓｃｈｗａｇｅｒｉｎａ带（Ｃｈａｌａｒｏｓｃｈｗａｇｅｒｉｎａｖｕｌｇａｒｉｓ亚带;Ｒｏｂｕｓｔｏｓｃｈｗａｇｅｒｉｎａｌｏｎｇｌｉｎｅｎｓｉｓ亚带）;４）Ｂｒｅｖａｘｉｎａｄｙｈｒｅｎｆｕｒｔｈｉ带;５）Ｍｉｓｅｌｉｎａｃｌａｕｄｉａｅ带。同时对命名地点常么组的定义、时代及岩相特征、生物群面貌进行了讨论。     

新疆塔里木盆地北部石炭纪孢子带及其地质意义

塔里木盆地北部石炭纪孢子花粉非常丰富,属种众多,保存完美,经研究共计有７４属,２３１种。根据孢子花粉演化及其在地层中的分布规律,自上而下划分出９个孢子带：９Ｐｒｏｐｒｉｓｐｏｒｉｔｅｓｌａｅｖｉｇａｔｕｓ－Ｇｒｕｍｏｓｉｓｐｏｒｉｔｅｓｖａｒｉｏｒｅｔｉｃｕｌａｔｕｓ（ＬＶ）带８Ｂｅｌｉｓｐｏｒｉｔｅｓｎｉｔｉｄｕｓ－Ｍｕｒｏｓｐｏｒａｃａｎｄｉｐｌｉｃａｔａ（ＮＣ）带７Ｒａｉｓｔｒｉｃｋｉａｎｉｇｒａ－Ｓｃｈｕｌｚｏｓｐｏｒａｃａｍｐｙｌｏｐｔｅｒａ（ＮＣ）带６Ｌｙｃｏｓｐｏｒａｐｕｓｉｌａ（ＰＵ）带５Ｓｃｈｏｐｆｉｔｅｓｃｌａｖｉｇｅｒ－Ａｕｒｏｒａｓｐｏｒａｍａｃｒａ（ＣＭ）带４Ｓｐｅｌａｅｏｔｒｉｌｅｔｅｓｐｒｅｔｉｏｓｕｓ－Ｒａｉｓｔｒｉｃｋｉａｃｌａｖａｔａ（ＰＣ）带３Ｓｐｅｌａｅｏｔｒｉｌｅｔｅｓｂａｌｔｅａｔｕｓ－Ｒｕｇｏｓｐｏｒａｐｏｌｙｐｔｙｃｈａ（ＢＰ）带２Ｋｒａｅｕｓｅｌｉｓｐｏｒｉｔｅｓｈｉｂｅｒｎｉｃｕｓ－Ｕｍｂｏｎａｔｉｓｐｏｒｉｔｅｓｄｉｓｔｉｎｃｔｕｓ（ＨＤ）带１Ｖａｌａｔｉｓｐｏｒｉｔｅｓｖｅｒｕｃｏｓｕｓ－Ｒｅｔｕｓｏｔｒｉｌｅｔｅｓｉｎｃｏｈａｔｕｓ?     

浙江桐庐地区船山组多重地层划分

桐庐沈村剖面船山组，主体为深灰色泥晶灰岩，厚138．77m，与下伏地层黄龙组、上覆地层梁山组均呈整合接触，是一个跨系的岩石地层单位。在该组中划分出5个化石带：下部为①Streptognathodus elegantulus牙形刺带和②Triticites subcrassulus（ting）带，归属逍遥阶；中部为③sphoeroschwagerina subrotunda（ting）带，归属紫松阶；上部为④EoparcoCusulina pseudosimplex（ting）带和⑤Sweetognathus paraguizhouensis牙形刺带，归属隆林阶。石炭系与二叠系的界线位于Triticites subcrassulus带与sphaeroschwagerina subrotunda带之间，即沈村剖面第15层与16层之间。船山组可划分出3个正层序（Os）和7个四级层序（Ss），主要成岩环境为潮坪相、台地相和台地边缘相3种类型。对船山组中-上部高频旋回研究显示，每个米级旋回层时限约0．3Ma，主要受地球偏心率长周期400ka的控制。     

广西宜山马平组的■类化石分带

本文讨论了广西宜山马平组(虫筳)类化石的分带情况,并和国内有关地区的上石炭——早二叠统的(虫筳)类化石带进行了对比。根据对采自宜山马脑山连续地层剖面上约120个(虫筳)类化石种的研究,该地马平组的(虫筳)类化石可自上而下分为三带、四亚带: 栖霞组 Misellina claudiae 带; 马平组 Ⅲ. Pseudoendothyra discalis(sp.nov.) 带; Ⅱ. Pseudoschwagerina 带; (4)Eoparafusulina simplex 亚带; (3)Sphaeroschwagerina subrotunda-Robustoschwagerina 亚带; (2)Pseudoschwagerina cheni 亚带; Ⅰ.Triticites 带; (1)Triticites simplex 亚带; 黄龙组 Fusulina-Fusulinella. 本文还比较详细地介绍了发育于该地马平组顶部的一个独特的(虫筳)类动物群——Pseudoendothyra动物群,对其对比问题进行了初步的探讨;同时还描述了6个(虫筳)类化石新种。     

Petrology of an Arc-Oceanic Crust Contact Zone in the Laohushan Back-arc Basin, the Eastern Section of the North Qilian Mountains, NW China

A contact zone sandwiched between an arc and an oceanic crust was discovered in the Laohushan area in the present study. It consists of a series of north-dipping imbricated thrust sheets and is exposed on the surface as a narrow arcuate belt, which extends for about 30 km in an E-W direction and measures about 1-3 km wide. Lithologically, it can be divided into four subzones. Subzone 1 consists of meta-andesite and metasandstone; subzone 2, psammitic schists; subzone 3, psammitic and pelitic schists, quartz diorite and hornfelses; and subzone 4, metagabbro, epidote amphibolite and pelitic schists. The metamorphism has the following grading sequence: low greenschist facies in subzone 1 → high greenschist facies in subzone 2 →low amphibolite facies in subzone 3→ epidote amphibolite facies in subzone 4. Petrographic and geochemical evidence shows that rocks in subzones 1, 2 and 3 are arc rocks, whereas those of subzone 4 are oceanic crustal rocks. The metamorphic mineral assemblages and especially miner     

山东淄博地区石炭纪含(竹蜓)地层

<正> 石炭纪含(竹蜓)地层在山东境内出露比较广泛,包括淄博、章邱、峄县、莱芜等地,以淄博及章邱一带出露较好。石炭纪含(竹蜓)地层可分为上石炭统本溪组和上石炭统太原组二部份,含(竹蜓)石灰岩的层数和厚度在山东各地不一,变化较大。谭锡畴(1922)在淄川、博山地层柱状图中,将含(竹蜓)石灰岩作为博山组(Poshan Formation)的下部,相当于山西的太原组。李四光、赵亚曾(1926)在山东境内找到三处石炭纪含(竹蜓)地层,即:章邱煤田、博山煤田及峄县煤     

中国三叠纪孢粉组合特征及其分区的初步探讨

文中介绍了我国陆相三叠纪的地层概况,重点对我国南北方孢粉组合进行了初步总结,并建立了三叠纪孢粉组合带。北方分三个带、四个亚带;南方(除早三叠世外)建立了三个组合带。同时根据孢粉组合特征,初步探讨了三叠纪的植物分区。     

鄂尔多斯盆地苏台庙地区砂岩地球化学环境和常量元素特征及对铀成矿的指示意义北大核心CSCD

为研究砂岩型铀矿与古层间氧化带之间的关系,本文通过对鄂尔多斯盆地苏台庙地区直罗组下段上亚段砂岩的地球化学环境和常量元素进行规律总结与讨论。将古层间氧化带进一步细分为古氧化残留带、二次还原带、叠置带和原生带等4个亚带,总结了各亚带地球化学环境指标特征,揭示了各亚带常量元素的演化规律,其中Si、Al、Fe和Ca活动性较强,Na、Mg和Ti活动性其次,而K、Mn和P较稳定。研究认为,该地区砂岩依次经历了成岩作用、古氧化作用、主成矿期铀成矿作用、二次还原作用和叠加铀成矿作用等,且未曾经历大幅沉降和显著构造热事件。研究区铀成矿作用与还原介质和Ca含量关系最密切,其次是Si、Fe、Ti,铀矿勘查应以叠置亚带为重点,兼顾二次还原亚带。     

十红滩地浸砂岩铀矿层间氧化带蚀变矿物群

十红滩砂岩型铀矿床是我国大型层间氧化带型砂岩铀矿床之一。层间氧化带型砂岩铀矿含矿砂层在含氧含铀水的渗入径流过程中,由于水介质性状的变化,在与砂体发生水岩作用时形成了完全氧化带、不完全氧化带、还原带和原生带等不同地球化学亚带及其相对应的蚀变矿物群,即完全氧化带为褐铁矿(针铁矿、水针铁矿)、伊利石、蒙脱石、少量黄钾铁矾的蚀变矿物群;不完全氧化带为褐铁矿(针铁矿、水针铁矿)、黄钾铁矾、蒙脱石、伊利石、少量绿泥石、高岭石的蚀变矿物群;还原带为沥青铀矿、黄铁矿、高岭石、绿泥石、少量蒙脱石、伊蒙混层粘土、伊利石和碳酸盐等新生蚀变矿物群;原生带的新生蚀变矿物群以黄铁矿、绿泥石、高岭石为主,有时出现少量碳酸盐、蒙脱石和伊利石等。     

广西六景泥盆纪吉维阶-弗拉斯阶界线层牙形石生物地层

广西六景泥盆系剖面是我国泥盆系标准剖面之一 ,通过对其吉维阶 -弗拉斯阶界线上下地层进行详细的牙形石生物地层研究 ,自上而下识别出 12个牙形石带 :Palmatolepis jamieae带、Palmatolepis hassi带、Palmatolepispunctata带、Palmatolepistransitans带、上 Mesotaxisfalsiovalis带、下 Mesotaxisfalsiovalis带、Klapperina dispar-ilis带、上 Schmidtognathus hermanni- Polygnathus cristatus带、下 Schmidtognathus hermanni- Polygnathus cristatus带、上 Polygnathus varcus带、中 Polygnathus varcus带、下 Polygnathus varcus带。吉维阶 -弗拉斯阶界线 (即中 -上泥盆统界线 )由 Ancyrodella binodosa→ Ancyrodella rotundiloba early form→ Ancyrodella rotundiloba late form这一演化线系中的 Ancyrodella rotundiloba early form的首次出现确定 ,处于下 Mesotaxis falsiovalis带下部 ,在谷闭组底界之上 1.80 m处。     

Petrology and Ni-Cu-Cr-PGE Mineralization of the Largest Mafic Pluton in Europe: The Early Proterozoic Burakovsky Layered Intrusion,Karelia, Russia

The largest mafic pluton in Europe (area = 630 km², thickness = 5 to 7 km) is the early Proterozoic (2445 ± 4 Ma; Pb-Pb) Burakovsky Layered Intrusion (BLI). It is located in the southern part of Russian Karelia, in the SE part of the Baltic Shield, within an Archean granite-greenstone terrain. The BLI is overlain by Quaternary deposits, and our present understanding of its character, composition, and internal structure is based on geophysical surveys and the nature of the rocks at depth, as sampled by diamond drill core. In order to better understand the petrogenesis of the BLI, we present geologic, petrographic, mineral-chemical, and whole-rock chemical analyses from throughout the stratigraphic sequence.

The BLI is a lopolith-like body and is divided into two major units: the Layered Series (LS), which exhibits layering that is discordant to the contact, and the Border Group (BG), with layering that conforms to the contact surface. The LS constitutes most of the BLI and consists of, from bottom to top: the ultramafic zone (UZ), 3 to 3.5 km thick, with a lower dunite (01 ± Chr) and an upper peridotite subzone (01 ± Chr, 01 + Opx ± Chr, and rare Chr cumulates); the pyroxenite zone (PZ) (Opx ± Chr ± 01, Opx + Cpx ± Chr ± 01), 0.2 km thick; the gabbronorite zone (GZ), 1.1 km thick and composed of a lower banded subzone (Opx, Opx + Cpx ± Chr, Opx + Pig ± Cpx cumulates) and an upper massive subzone (Opx + Cpx + Pig and Pig cumulates); the pigeonite-gabbronorite zone (PGZ) (Pig + inverted Pig, Pig-Aug + Pig cumulates), 1.2 km in thickness; and the magnetite-gabbrodiorite zone (MGZ) (Ti-Mt + Pig + Pig + Cpx), 0.8 km thick.

A quite unusual feature of the BLI is an irregular conformable body of clinopyroxenite, in the lower part of the PZ, which consists of inverted Pig-Aug with a non-cumulate texture. The pyroxenites contain occasional relict cumulate structures. The pyroxenes contain small oval-shaped quartz-carbonate inclusions. We speculate that the clinopyroxenites may be the result of subsolidus metasomatism by fluids likely generated within the intrusion.

Economic mineralization is represented by chromite, Ti-V-Mt, and platinum-group minerals (PGMs). Chromite mineralization is well developed in the upper peridotite subzone of the UZ. The largest chromite seam—the main chromite horizon (MCH)—is 3 to 4 m thick and is situated at the top of the UZ, in contact with the PZ. Potential reserves of Ni, in both sulfides and olivine, are present in the UZ. Syngenetic platinum-group-element (PGE) mineralization is observed in chromitite layers in the layered subzone of the GZ and in the rocks of the Border Group. In the MCH, Os, Ir, and Rh occur as small inclusions of sulfides in chromite; these inclusions have compositions that would place them within the aurite-erlichmanite and isoferroplatinum-awaruite series. Low-sulfur PGE mineralization (mainly Pd and Pt) occurs in the banded subzone of the GZ and in sulfide-bearing rocks of the BG. PGMs consist of Pd- and Pt-bearing tellurides and bismuthides: moncheite, merenskyite, froodite, sobolevskite, and kotulskite. Epigenetic PGE mineralization also occurs in tectonic breccias.

The BLI is similar in many respects to other early Proterozoic layered mafic intrusions (i.e., the Bush veld, Monchetundra, and Koilismaa intrusions), especially in terms of the general rock sequence and economic mineralization. The main differences are the very thick dunite cumulates (comprising half of the intrusion) and the relatively minor proportion of pyroxenerich and plagioclaserich cumulates. Another contrasting feature is the predominance of refractory PGE (Os, Ir, and Rh), over Pt and Pd, in the MCH. This observation leads to the interpretation that the MCH has a non-cumulate (deuteric hydrothermal?) origin.     

Storm deposits and storm-generated coarse carbonate breccias on a pelagic outer shelf (South-East Basin, France)

Uppermost Jurassic limestones of the South‐East Basin (France) are organized into four facies associations that were deposited in four distinct zones: (1) peritidal lagoonal limestones; (2) bioclastic and reefal limestones; (3) pelagic lime mudstones; (4) lime mudstones/calcarenites/coarse breccias. Calcarenite deposits of zone 4 exhibit sedimentary structures that are diagnostic of deposition under wave‐induced combined flow. In subzone 4a, both vertical and lateral transitions from lime mudstone/calcarenite to breccia indicate in situ brecciation under wave‐cyclic loading. Breccias were produced by heterogeneous liquefaction of material previously deposited on the sea floor. Deposits in subzone 4a record relatively long periods (>400 kyr) of sedimentation below wave base, alternating with periods of deposition under wave‐induced currents and periods of in situ deformation. In this zone, storm waves were attenuated by wave–sediment interaction, and wave energy was absorbed by the deformation of soft sediment. With reference to present‐day wave attenuation, water depths in this zone ranged between 50 and 80 m. Landwards of the attenuation zone, in zone 3, storm waves were reduced to fair‐weather wave heights. Storm wave base was not horizontal and became shallower landwards. As a consequence, water depth and wave energy were not linearly related. On a small area of the seaward edge of subzone 4a, cobbles were removed by traction currents and redeposited in subzone 4b. There, they formed a 100‐m‐thick wedge, which prograded over 3 km and was built up by the stacking of 5‐ to 20‐m‐thick cross‐stratified sets of coarse breccia. This wedge records the transport and redeposition of cobbles by a high‐velocity unidirectional component of a combined flow. The increase in flow velocity in a restricted area is proposed to result from flow concentration in a channel‐like structure of the downwelling in the gulf formed by the basin. In more distal subzone 4c, the hydrodynamic effect of wave‐induced currents was quasi‐permanent, and brecciation by wave–sediment interaction occurred only episodically. This indicates that, seawards of the attenuation zone, hydrodynamic storm wave base was deeper than mechanical storm wave base. Uppermost Jurassic carbonates were deposited and soft‐sediment deformed on a hurricane‐dominated ramp of very gentle slope and characterized by a zone of storm wave degeneration, located seawards of a zone of sedimentation below wave base.     

关中平原500～10ka BP黄土地层岩溶作用研究

根据关中平原黄土地层岩溶作用产物的研究,可将该区500～10ka BP黄土地层岩溶作用分为北亚热带侵蚀-溶蚀型、湿暖湿润带强溶蚀-侵蚀型、温冷半湿润带中溶蚀-侵蚀型和温冷半干旱带弱溶蚀-侵蚀型4种。根据古土壤发育时岩溶作用垂向分带遗迹,可将前人划分的渗流带进一步分为上部非饱和循环强溶蚀亚带、中部过饱和循环沉淀亚带和下部不稳定循环弱溶蚀-弱沉淀亚带。3个亚带的划分对确定CO_2在垂向上的循环有重要指示意义。该区500～10ka BP可分为10个岩溶发育阶段,构成5个岩溶旋回,发展趋势是由强变弱。