河北省磁县虎皮脑晚寒武世和早奥陶世牙形石

在河北省磁县虎皮脑寒武纪–奥陶纪地层剖面发现晚寒武世和早奥陶世牙形石。晚寒武世牙形石包括Hirsutodontus rarus, Teridontus nakamurai,属于华北地区上寒武统凤山阶Proconodontus-Rotundoconus带牙形石。早奥陶世牙形石主要有Paraserratognathus partodiformis, P. problematicus, P. obesus, Scolopodus mancordatus, S.rexhuolianzhaiensis,Drepanodussubarcuatus,属于华北地区下奥陶统亮甲山组上部Paraserratognathus带牙形石。本文描述牙形石6属13种,其中包括l新种, 1亲近种。     

河北唐山达瑞威尔阶(Darriwilian)牙形刺生物地层的新认识

本文作者对河北唐山赵各庄剖面的北庵庄组(原称下马家沟组)和马家沟组(原称上马家沟组)较系统地采集了牙形刺样品,通过对所获之牙形刺标本和安太库等(1983)在同一剖面所描述的牙形刺动物群仔细研究,得到一些新的认识、分带及对比意见。唐山赵各庄剖面不仅具有丰富各异的地方型分子,如Aurilobodus leptosomatus,Loxodus dissectus,Tangshanodus tangshanensis,Rhipidognathus maggolensis,R.laiwuensis,Triangulodus changshanensis和Erraticodon tangshanensis外,尚有一些分布广泛和具地层意义的重要分子,如Histiodella holodentata,Eoplacognathus pseudoplanus和Eoplacognathus suecicus等。根据这些重要分子和牙形刺分带原则,本文对安太庠等(1983)的牙形刺分带重新修订,即将北庵庄组的Aurilobodus leptosomatus-Loxodus dissectus带和Tangshanodus tangshanensis带修正为Histiodella holodentata-Tangshanodus tangshanensis带,并由下而上可划分为Rhipidognathus maggolensis和R.laiwuensis两地方型亚带;将马家沟组的Eoplacognathus suecicus-Acontiodus?linxiensis带和Plectodina onychodonta带修正为Eoplacognathus suecicus带,并由下而上又可划分为Acontiodus?linxiensis和Plectodina onychodonta两个地方型牙形刺亚带。因此,唐山地区的北庵庄组产牙形刺的部分和马家沟组可与华南的牯牛潭组和新疆塔里木盆地的大湾沟组对比,归入奥陶纪达瑞威尔阶(Darriwilian),从而改变了过去将北庵庄组产牙形刺的层位,即所谓的Aurilobodus leptosomatus-Loxodus dissectus带和Tangshanodus tangshanensis带与华南区大坪阶(Dapingian)的大湾组相对比的认识。     

黔中贵阳乌当地区下-中奥陶统的牙形刺生物地层

奥陶纪时期紧邻黔中古陆南缘的贵阳乌当发育有富含牙形刺的碳酸盐岩沉积,但生物地层研究非常薄弱。本文对乌当地区小谷龙剖面和豹子窝剖面的奥陶系进行牙形刺生物地层研究,共识别出10个牙形刺带,自下而上为Chosonodina herfurthi带、Drepanodus arcuatus带、Triangulodus bifidus带、Serratognathus diversus带、Oepikodus evae带、Baltoniodustriangularis带、Baltoniodusnavis带、Baltoniodusnorrlandicus带、Lenodusantivariabilis带和Dzikodustablepointensis带,时代属于下奥陶统特马豆克阶至中奥陶统达瑞威尔阶,可与华南同期地层的化石带对比。根据牙形刺生物地层,本研究构建了乌当地区奥陶系的年代地层格架,并限定黔中古陆南缘开始暴露出水面的时间为不晚于中奥陶世达瑞威尔期早期。     

山东省青州地区寒武-奥陶系界线研究的新进展

首次报道了山东省青州地区尧王山剖面的寒武 奥陶系界线地层的牙形石生物地层学的最新研究成果,在该剖面的炒米店组灰岩建立了 9个牙形石带,其中下奥陶统为 3个带,上寒武统凤山阶为 6个带;并与国内外研究较详细的寒武 奥陶系界线地层进行了对比。在该剖面首次发现了界线牙形石分子Iapetognathusfluctivagus,这也是在整个华北地区的首次报道,这一发现为山东地区乃至整个华北地区的寒武 奥陶系的界线划分提供了新的标尺。     

吉林浑江地区奥陶纪新厂阶笔石序列——兼论寒武-奥陶系界线

研究简史吉林浑江地区下奥陶统发育良好,剖面连续,化石丰富,研究历史也早.1958-1960年,长春地质学院吉南区测大队于浑江地区进行1/20万区域地质调查,测制奥陶系剖面,并采集了笔石等大量化石.1979年,吉林省地质局根据南京地质古生物所对笔石的研究,在靖宇县(1/20万)区域地质调查报告中报道了 Adelograptus-Clonograptus 带在本区的存在.陈均远等(1983),周志毅等(1984)均指出本区冶里组底部有 Dictyonema flabelliforme-Staurograptus dichotomus 带.1983年,林尧坤将华北区下奥陶统冶里组分为5个笔石带,并指出吉林辉南、浑江等地的冶里组亦有这些笔石带的带     

微体古生物学发展的新成果——介绍《下扬子地区牙形刺——生物地层与有机变质成熟度的指标》一书

由王成源教授主编、丁连生、段金英等十几位作者共同撰写的《下扬子地区牙形刺》一书即将由科学出版社出版。这是一部下扬子地区牙形刺化石的全面系统的总结。书中收集了下扬子地区76条剖面、7 840个牙形刺样品的资料;建立了从寒武纪至二叠纪的53个牙形刺化石带或组合带;依据牙形刺化石修订了传统的地层界线;并对全球二叠纪地质年表提出了新的见解,且在下扬子区首次发现了志留纪牙形刺化石。全书共约     

浙西寒武—奥陶系的分界及所含三叶虫

浙西地区是东南区系江南一西北亚区上寒武统上部西阳山组及下奥陶统下部印渚埠组的标准地点。寒武系与奥陶系呈整合接触,界线上下的岩层连续沉积,岩性逐渐过渡,为灰黑色钙质页岩夹黑灰色薄层致密灰岩、瘤状灰岩及泥灰岩。所含的三叶虫化石大多沿层面分布,大小分选不显,常见保存较完整的个体标本,一般不见水流冲涮的迹象。根据岩性和化石埋葬的产状分析,反映了海水较深的还原或次还原条     

湖北宜昌黄花场下奥陶统弗洛阶Oepikodus evae带精细地层划分对比

全球中奥陶统及奥陶系第三个阶、大坪阶的界线层型剖面和点位(GSSP)确定后,文中作者对宜昌黄花场剖面弗洛阶上部Oepikodus evae带牙形刺生物地层序列进行再研究。通过对红花园组上部-大湾组下段一些关键层位中牙形刺样品的补充采集和牙形刺标本的系统检查,研究牙形刺属种垂向分布特征,修订一些牙形刺属种的首现层位。讨论Stolodus stola,Lundodus gladiatus,Oepikodus intermedius,Oepikodus communis,Trape-zognathus diprion,Baltonioduscf.B.triangularis等重要的多分子器官种分类问题。识别出Baltoniodus trian-gularis(Lindstr m)的先驱:Baltonioduscf.B.triangularis(Lindstr m)与Baltoniodus triangularis(Lindstr m)的区别。描述新建化石带属种,包括Baltoniodus triangularis(Lindstr m)。认为Oepikodus evae带上部时限范围内并未见Oepikodus evae分子,所以与国际地层指南(2000)关于间隔带和延限带的含义相悖。据此,厘定了原Oepikodus evae带的含义。并以牙形刺带分子首现为标志,将大湾组下段自下而上划分为3个间隔带,分别为:O.evae带,Trapezognathus diprion带和Baltonioduscf.B.triangularis带。其中Trapezognathus diprion带和Baltonioduscf.B.triangularis带为新建化石带。     

澄江动物群在云南晋宁梅树村的发现

前言云南晋宁梅树村剖面位于北纬24°44',东经102°34'(插图1),是国际前寒武系-寒武系界线候选层型剖面之一.1984年8月,侯先光在此剖面工作时,在下寒武统筇竹寺组 Eoredlichia-Wutingaspis 带一层灰绿、灰黄色泥岩内(野外号 AEF-k10)发现了少量水母、蠕虫、大型双瓣壳节肢动物等化石.     

湖北宜昌真金和陈家河奥陶系牯牛潭组至宝塔组的牙形刺及其地层意义

根据采自湖北宜昌分乡陈家河和远安真金两剖面奥陶系牯牛潭组至宝塔组的牙形刺,将该段地层的牙形刺生物带自上而下综合划分为Hamarodus brevirameus,Amorphognathus superbus,Baltoniodus alobatus,Pygodus anserinus-Yangtzeplacognathus jianyeensis,Yangtzeplacognathus protoramosus,Yangtzeplacognathus foliaceus,Histiodella kristinae-Eoplacognathus suecicus,Dzikodus tablepointensis,Lenodus variabilis和Lenodus antivariabilis等牙形刺生物带。其中宝塔组之Hamarodus brevirameus,Amorphognathus superbus生物带及Baltoniodus alobatus生物带顶部归为凯迪阶(Katian),庙坡组Baltoniodus alobatus生物带大部和Pygodus anserinus-Yangtzeplacognathus jianyeensis生物带中上部归为桑比阶(Sandbian),而牯牛潭组的Yangtzeplacognathus protoramosus至Lenodus antivariabilis等牙形刺生物带和庙坡组Pygodus anserinus-Yangtzeplacognathus jianyeensis生物带下部则归入达瑞威尔阶(Darriwillian)。这一牙形刺带序列与宜昌黄花场和分乡剖面的牙形刺生物带相一致。     

EARLY ORDOVICIAN CONODONTS FROM TARUTAO ISLAND,SOUTHERN PENINSULAR THAILAND

Abstract: Early Ordovician conodont faunas of the Thung Song Formation on Tarutao Island, southern peninsular Thailand, consist of 14 known species belonging to 17 genera, and eight undescribed species. Utahconus tarutaoensis and Filodontus tenuis are new species. Three conodont zones: the Rossodus manitouensis Zone, the Utahconus tarutaoensis Zone and the Filodontus tenuis Zone, in ascending order, are defined in the study sections. These are coeval with the interval from the Rossodus manitouensis Zone to the Acodus deltatus‐Oneotodus costatus Zone of the standard zonation in the North American Midcontinent. Based on the conodonts studied here and fossils previously reported from Tarutao Island, the Thung Song Formation is early Tremadocian to middle Arenig (Ibexian) in age. This formation is lithostratigraphically subdivided into the S1 to S5 members, and our study sections consist of the S1 to S3 members. These strata accumulated on a shelf in the Early Ordovician. The depositional environments of the limestones making up the S1 and S3 members were in deeper‐shelf conditions. Limestone and shale of the S2 member formed in a shallow‐water, high‐energy environment.     

新疆准噶尔盆地西北缘洪古勒楞组时代的新认识

标准地点的洪古勒楞组长期以来一直被认为是准噶尔盆地西北缘,乃至整个新疆北部以海相为主的层位上最高的晚泥盆世晚期的沉积。然而牙形类和微体脊椎动物的研究证实,该组跨弗拉阶－法门阶（Ｆ－Ｆ）界线,它至少包括了一小部分弗拉晚期和主体部分为法门早期的沉积。两个牙形类带ＬａｔｅｒｈｅｎａｎａＺｏｎｅ和ＭｉｄｄｌｅｃｒｅｐｉｄａＺｏｎｅ被识别出,它们在Ｆ－Ｆ界线附近,并分别在大绝灭事件（在ｌｉｎｇｕｉｆｏｒｍｉｓＺｏｎｅ内）之前后。另一个层位更高的牙形类带ＬａｔｅｃｒｅｐｉｄａＺｏｎｅ也可能存在。同时还证实,长期以来一直被认为“正常层序”的标准地点的洪古勒楞组的层序是倒转的。由此,含植物大化石Ｌｅｐｔｏｐｈｌｏｅｕｍｒｈｏｂｉｃｕｍ等的陆相层在下（此层可能归于该组下伏的朱鲁木特组）,而产牙形类和其它丰富的无脊椎动物的海相层在上。按牙形类年代带的年代地层时间表（Ｆｏｒｄｈａｍ,１９９２）,该组距今约３６８－３６４百万年。至于它和邻近地区和布克河组的关系,由于后者发现了更高层位的牙形类,两者还不能完全对比。     

湖北宜昌黄花场剖面中/下奥陶统界线附近的牙形剌

重点描述宜昌黄花场剖面中 /下奥陶统界线附近的重要牙形剌共 3属、5种和 2新种Bergstroe mognathussp .nov .,BaltoniodustetrachotomusLiandWangsp .nov .,并对Oepikodusevae带和Baltoniodustriangu laris带分子的首现位置及带的含义进行厘定。作者还在此剖面大湾组下段发现北美中大陆区暖水型牙形剌Tripoduslaevis和Protoprioniodusaranda ,并确定Tripoduslaevis的首现位置在Baltoniodustriangularis带底界之上 0 .3m处。Tripoduslaevis的首次出现曾提议为中奥陶统的底界的标志 (见陈旭等 ,2 0 0 0 ) ,在宜昌黄花场剖面上Tripoduslaevis的首现位置接近Baltoniodustriangularis带底界 ,对确定中 /下奥陶统界线很重要。由于在黄花场剖面可识别出Baltonioduscrassulus—B .gladiatus—B .triangularis演化谱系 ,作者建议以B .triangularis的首次出现作为中奥陶统的底界 ,宜昌黄花场剖面为中 /下奥陶统界线的层型剖面。同时 ,文中将本区的牙形刺带与世界其它地区作了对比。     

湖北宜昌远安真金和界岭奥陶系牯牛潭组顶部的牙形刺及其地层意义（英文）

本文描述了采自湖北宜昌远安真金和界岭剖面奥陶系牯牛潭组顶部的牙形刺,它们有Baltoniodus prevariabilis,Drepanoistodus venustus,Panderodus gracilis,Periodon aculeatus,Protopanderodus calceatus,P.varicostatus?,Yangtzeplacognathus foliaceus和Y.protoramosus等,确认宜昌地区牯牛潭组顶部应归属于奥陶系达瑞威尔阶Pygodus serra带之Yangtzeplacognathus protoramosus亚带,并可与宜昌黄花场剖面和南京汤山外杆沟剖面同名组顶部及新疆柯坪羊吉坎剖面一间房组顶部的牙形刺带相对比。同时,它要比重庆城口大槽剖面牯牛潭组顶部的牙形刺带低3个带(Pygodus anserinus带至Baltoniodus variabilis带),这一事实也说明了牯牛潭组顶部在中国扬子地台的穿时性。     

Tremadocian (Ordovician) biostratigraphy and graptolites at Dayangcha (Baishan,Jilin, NE China)

Based on a systematic study of Tremadocian graptolites from the Early Ordovician Yehli Formation at Dayangcha, Baishan of Jilin, NE China, a revised graptolite zonation is proposed for the Tremadocian rocks in the area. In ascending order, the graptolite zones include theRhabdinopora flabelliformis parabola Zone, theAnisograptus matanensis Zone, thePsigraptus jacksoni Zone and theAorograptus victoriae Zone. The first three zones are discussed with their definitions and durations clarified, whereas the last zone is introduced for the first time as a replacement of the formerAdelograptus-Clonograptus Zone. The entire Yehli Formation is considered to be older than the late Tremadocian Hunneberg Substage of Scandinavia, the latter being represented by the carbonate-dominated basal part of the overlying Liangchiashan Formation where no graptolites have so far been discovered. The Tremadocian succession in the Dayangcha area is regarded as being representative of the North China (Sino-Korea) Palaeoplate, and a correlation of the Tremadocian graptolite sequence with those of other continents is suggested. Nine species belonging toDendrograptus, Aspidograptus, Callograptus andAirograptus of the family Dendroidae, and eight species ofPsigraptus, Adelograptus, Aorograptus andKiaerograptus of the family Anisograptidae are described and some are revised in the present paper. Among the important revisions are the reconstructed proximal development ofPsigraptus jacksoni based on partially three-dimensional specimens from the area, and the complex thecal structures ofAspidograptus.      

贵州沿河土地坳下奥陶统牙形石

本文报道了采自贵州沿河土地坳下奥陶统的牙形石,计有２５属３９种,根据牙形石组合特片分析,认为其与黔北其它地区下奥陶统牙形石组合面貌基本一致,属北大西洋牙形石动物地理区。     

广西桂林泥盆纪牙形刺组合序列与海平面变化

本文以桂林灵川岩山圩中,晚泥盆世界线剖面,桂林沙河能源疗养院背后信都组－唐家湾组剖面及桂林额头村Ｄ／Ｃ界线剖面的牙形刺资料为基础,结合前人在桂林地区所做的牙形刺生物地层工作,识别出该区中,晚泥盆世牙形刺化石的１６个组合序列,并以此为尺度结合层序地层格架,层序界面及层序中的微相叠加形式,讨论该区中,晚泥盆世高分辨的海平面变化。     

Proposed stratotype for the base of the highest Cambrian stage at the first appearance datum of Cordylodus andresi, Lawson Cove section, Utah, USA

We propose a candidate for the Global Standard Stratotype-section and Point (GSSP) for the base of the highest stage of the Furongian Series of the Cambrian System. The section is at Lawson Cove in the Ibex area of Millard County, Utah, USA. The marker horizon is the first appearance datum (FAD) of the conodont Cordylodus andresi Viira et Sergeyeva in Kaljo et al. [Kaljo, D., Borovko, N., Heinsalu, H., Khazanovich, K., Mens, K., Popov, L., Sergeyeva, S., Sobolevskaya, R., Viira, V., 1986. The Cambrian–Ordovician boundary in the Baltic–Ladoga clint area (North Estonia and Leningrad Region, USSR). Eesti NSV Teaduste Akadeemia Toimetised. Geologia 35, 97–108]. At this section and elsewhere this horizon also is the FAD of the trilobite Eurekia apopsis (Winston et Nicholls, 1967). This conodont characterizes the base of the Cordylodus proavus Zone, which has been recognized in many parts of the world. This trilobite characterizes the base of the Eurekia apopsis Zone, which has been recognized in many parts of North America. The proposed boundary is 46.7 m above the base of the Lava Dam Member of the Notch Peak Formation at the Lawson Cove section. Brachiopods, sequence stratigraphy, and carbon-isotope geochemistry are other tools that characterize this horizon and allow it to be recognized in other areas.     

川东北二叠纪吴家坪期牙形石（刺）序列及其世界对比

对四川省宣汉县渡口和南江县桥亭吴家坪期地层的系统采集和研究结果表明,吴家坪期至少包括７个牙形石带,自下而上为Ｃｌａｒｋｉｎａｄｕｋｏｕｅｎｓｉｓ带,Ｃ．ａｓｙｍｍｅｔｒｉｃａ带,Ｃ．ｌｅｖｅｎｉ带,Ｃ．ｇｕａｎｙｕａｎｅｎｓｉｓ带,Ｃ．ｔｒａｎｓｃａｕｃａｓｉｃａ带,Ｃ．ｏｒｉｅｎｔａｌｉｓ和Ｃ．ｉｎｆｌｅｃｔａ带。其中,前３个带的层位低于一直作为吴家坪期早期的Ｃ．ｌｉａｎｇｓｈａｎｅｎｓｉｓ带。吴家坪阶的顶界以置于Ｃ．ｉｎｆｌｅｃｔａ带与Ｃ．ｓｕｂｃａｒｉｎａｔａ带之间较妥。同时,建立了Ｃｌａｒｋｉｎａｄｕｋｏｕｅｎｓｉｓ,Ｃ．ａｓｙｍｍｅｔｒｉｃａ,Ｃ．ｂｉｚａｒｒｅｎｓｉｓ,Ｃ．ｄａｘｉａｎｅｎｓｉｓ,Ｃ．ｄｅｍｉｃｏｒｎｉｓ,Ｃ．ｉｎｆｌｅｃｔａ,Ｃ．ｌｏｎｇｉｃｕｓｐｉｄａｔａ等７个新种。