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Graptolite, Chitinozoan and Scolecodont Reflectances and Their Use as Indicators of Thermal Maturity

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Acta Geologica Sinica(English Edition) 1993年第1期67卷 93-105,125-126页

作者： Andreas Hoffknecht Rainer Bainer Brocke bernd-d. erdtmann Institute of Geology and Paleontology Technical University of Berlin Berlin Germany

Based on studies of the reflectance of Ordovician and Silurian zooclasts from 11 sections around the Huangling Anticline, Hubei, China, combined with determination of the conodont colour alteration indices (CAI) and of infrared spectroscopy of dispersed organic matter from the same or adjacent horizons, it is further proved that reflectances of graptolites, chitinozoans and scolecldonts, like vitrinite and natural bitumen, increase with increasing maturation, but follow different reflectance paths. They may be used, therefore, as thermal maturation indicators. Graptolites display optically strong anisotropy. The maximum reflectance measured from graptolite on polished section cut parallel to the bedding plane is the most suitable for determination of maturation of their host rocks. In polished section chitinozoan and scolecodont show reflectance, but no bireflectance owing to their isotropy. The random reflectance of chitinozoans is higher than that of scolecodonts in the case of the same maturity. By analysing the distribution trends of graptolite, chitionzoan and scolecodont reflectances, the Ordovician and Silurian strata can be subdivided into three areas of maturation in the present region. The potential of oil or gas generation is discussed for each area. The result is basically coincident with the distribution pattern of regional organic maturation presented by CAI and infrared spectroscopic determination of organic matter.

关键词： graptolite chitinozoan scolecodont reflectance

A proposed GSSP for the base of the Middle Ordovician Series： the Huanghuachang section,Yichang, China

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Episodes 2005年第2期28卷 105-117页

作者： XiaofengWang SvendStouge bernd-d.erdtmann XiaohongChen ZhihongLi ChuanshangWang QingluanZeng ZhiqiangZhou HuimingChen YichangInstituteofGeology＆MineralResources YichangHubei443003China GeologicalMuseum UniversityofCopenhagenΦsterVoldgade5-7DK-1350CopenhagenKDenmark. InstitutfuerAngewandteGeowissenschaften TechnicalUniversityBerlinGermany. Xi＇anInstituteofGeology＆MineralResources Xi＇anShangxi710054China.

The Huanghuachang section near Yichang, southern China meets the requirements of Global Stratotype Section and Point (GSSP) for the base of the Middle Ordovician Series and the yet-to-be-named third stage of the Ordovician System (or lower stage of Middle Ordovician Series). The conodont succession at the section is complete across the Lower to Middle Ordovician series boundary and several excellent phylogenetic lineages of Baltoniodus, Trapezognathus, Periodon, and Microzarkodina are represented. The definition of the base of the Middle Ordovician is proposed to be the first appearance datum (FAd) of Baltoniodus? triangularis in the section. It is followed closely by the FAd of Microzarkodina flabellum, which is taken as a reasonable proxy for the boundary. This level approximates the boundary between the lower and upper intervals of the Azygograptus suecicus graptolite Biozone, and nearly coincides with the base of the Belonechitina henryi chitinozoan *** proposed GSSP for the base of the international Middle Ordovician Series is located in a roadside exposure at the base of Bed (SHod) 16, 10.57 m above the base of the dawan Formation in the measured Huanghuachang section near Yichang City, southern China. The same faunal succession is also recorded from the Chenjiahe (formerly daping) section, 5 km to the north of the Huanghuachang section. The proposed boundary horizon can be recognized and correlated globally with high precision in both relatively shallow-water carbonate facies as well as in deep-water graptolite facies.

关键词： GSSP 奥陶纪宜昌市地质分层研究地形特征

Eocrinoid echinoderms from the Lower Cambrian Guanshan Fauna in Wuding,Yunnan,China

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Chinese Science Bulletin 2007年第5期52卷 717-719页

作者： HU ShiXue LUO HuiLin HOU ShuGuang bernd-d.etrich erdtmann Yunnan Institute of Geological Sciences Kunming 650011 China Technische Universitat Bedin D-13355 Berlin Germany

This is a brief report of a new occurrence of eocrinoids from the Early Cambrian Wulongqing Formation in Yunnan, China. The eocrinoids from the Guanshan fauna are among the earliest known eocrinoids. different from many other Early and Middle Cambrian eocrinoids, the Guanshan eocrinoids are char-acterized by the absence of sutural pores and epispires, the long and spiral brachioles, the extremely long stalk, and the ratio of the length of the stalk versus that of the calyx. The discovery of the eocri-noids from the Guanshan fauna not only provides new information to the investigation of the early evolution of this animal group, but also shed new light on the occurrence and migration of early eocrinoids.

关键词：棘皮类动物下寒武统关山动物群化石云南武定

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中国吉林浑江最早奥陶纪的笔石序列

地质学报 1986年第3期60卷 226-236+311-314页

作者：汪啸风 bernd-d.erdtmann 中国地质科学院宜昌地质矿产研究所联邦德国格廷根大学地质古生物研究所和博物馆

根据对吉林省东南浑江大阳岔附近的小杨桥和浑江城附近的青沟子和木掀头沟剖面笔石序列的研究,在该地的“冶里组”中可以划分出以下5个笔石带:*** parabola带,***带,***带,***?taizehoentis带,***-Clonograptus带。并对每一个笔石带与... 详细信息

根据对吉林省东南浑江大阳岔附近的小杨桥和浑江城附近的青沟子和木掀头沟剖面笔石序列的研究,在该地的“冶里组”中可以划分出以下5个笔石带:*** parabola带,***带,***带,***?taizehoentis带,***-Clonograptus带。并对每一个笔石带与国内外相当带的对比及寒武-奥陶系界线问题进行了讨论。

关键词：冶里组奥陶系寒武系界线笔石带浑江市奥陶纪吉林序列最早中华人民共和国

Lower Cambrian small shelly faunas from Zhejiang (China) and their biostratigraphical implications

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Progress in Natural Science:Materials International 2003年第11期 52-60页

作者： Michael STEINER,bernd-d. erdtmann TU Berlin Sekr. ACK 14 Ackerstrasse 71～76 13355 Berlin Germany TU Berlin Sekr. ACK 14 Ackerstrasse 71～76 13355 Berlin Germany

despite a long history of research on the Early Cambrian in China most available data on small skeletal fossils concern fossil associations of the shallow carbonate platform. Information on skeletal fossils from marginal shelf environments of the Yangtze Platform is scanty, which may reflect the rarity of fossils in deeper sedimentary environments but is also due to limitation of carbonate distribution and outcrops, difficulties in fossil extraction, and a general research focus on the Precambrian—Cambrian boundary beds on the carbonate platform. Here we present a documentation of Meishucunian to Qiongzhusian small skeletal fossils from the lower Hetang Formation and the chert unit at its base from the Jiangshan region, Zhejiang Province, representing a relatively deep shelf environment compared to the inner shelf region. The earliest association (Meishucunian) from the chert unit underlying the Hetang Formation is mainly characterized by the occurrence of Protohertzina anabarica, P. unguliformis, Fengzuella zhejiangensis, and Kaiyangites novilis, which differs somewhat in composition from SSF-associations of typical inner shelf deposits. The enigmatic skeletal fossil Fengzuella zhejiangensis, which exhibits an unusual secretional growth mode previously unrecognized from the Early Cambrian, is described in detail. A younger (Qiongzhusian) fossil association contains numerous arthropod remains, such as disarticulated spines of arthropods (Jiangshanodus- and Kijacus-type), which have previously been considered as conodont-like fossils, and bradoriid valves.

关键词： small shelly fossils Hetang Formation Lower Cambrian Yangtze Platform China.

Early Cambrian protoconodonts and conodont-like fossils from China: Taxonomic revisions and stratigraphic implications

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Progress in Natural Science:Materials International 2004年第2期 77-84页

作者： Michael STEINER,bernd-d.erdtmann Technische Universitt Berlin Sekr. ACK14 Technische Universitt Berlin Sekr. ACK14 Ackerstrasse 71-76 d-13355 Berlin Germany Ackerstrasse 71-76 d-13355 Berlin Germany

Protoconodonts and conodont-like microfossils are characteristic components in the early Cambrian skeletal faunas. Since the 1970s, these tooth-like phosphatic sclerite fossils have been widely recovered from the Lower Cambrian of China, and altogether 25 genera and 52 species of protoconodonts and conodont-like fossils have been described, although some taxa represent synonyms or invalid taxonomic names, and some assignments are apparently inappropriate. Through a brief review and discussion, the distinction between protoconodonts and conodont-like fossils is denoted here. There are 13 genera previously assigned to protoconodonts in the literature, but present taxonomic revisions show that 5 of them are junior synonyms of other taxa, and 2 represent unknown arthropods. The other 12 genera, of which 5 also are junior synonyms, only reveal a conodont-like morphology with various zoological affinities: most of them are enigmatic, and only Beshtashella and Parafomitchella (= Beshtashella ) can be assigned to mollusks. The spatial and temporal distribution of the most genera is briefly discussed. Three intervals of stratigraphic distribution for the protoconodonts not only have significant implications for stratigraphic correlations but also may reflect their evolutionary trend.

关键词： protoconodonts conodont-like fossils Small Shelly Fossils Early Cambrian China.

Early Paleozoic whole-rock Ce anomalies and secular eustatic changes in the Upper Yangtze region

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Science China Earth Sciences 2000年第3期43卷 328-336页

作者：冯洪真 B.-d.erdtmann 王海峰 State Key Laboratory for Research of Mineral deposits Nanjing University Nanjing 210093 China Institut fur Angewandte Geowissenschaften II Technologische Universitat Berlin 10587 Deutschland Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210093 China

The 65 whole-rock REE samples studied come from the classic sections of Early Cambrian to Early Silurian in the Yichang area, Hubei Province. REE concentrations tested on ICP-AES are normalized to the North American Shale Composite (NASC), and Ce anomaly values are calculated based on log[3Cen(2Lan+Ndn)]. With the whole-rock Ce anomaly used as a quantitative index of sea-level changes, 5 prominent eustatic circles are recognized, and a good corresponding relationship is observed between the black shale episodes and the transgressive events. On account of the global distributions of coeval black shales and the specified paleogeographic background of South China, a genetic hypothesis based on the model of O2-minimum zone expansion is suggested for the Early Paleozoic multi-episode black shales in South China.

关键词： whole-rock Ce anomalies eustatic circles geneses of black shales.

上扬子区早古生代全岩Ce异常与海平面长缓变化

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中国科学（d辑） 2000年第1期30卷 66-72页

作者：冯洪真 bernd-d.erdtmann 王海峰南京大学成矿作用研究国家重点实验室南京210093 Institute of Applied GeosciencesⅡ Technical University Berlin 中国科学院南京地质古生物研究所南京210008

65个全岩稀土样品采自湖北省宜昌地区下寒武统至下志留统的经典剖面 .样品测试由单通道扫描等离子光谱仪 (ICP AES)完成 .REE含量依北美页岩组合(NASC)标准化 ,并按log[3Cen/ ( 2Lan+Ndn) ]计算Ce异常值 .以全岩Ce异常作为海平面变化的... 详细信息

65个全岩稀土样品采自湖北省宜昌地区下寒武统至下志留统的经典剖面 .样品测试由单通道扫描等离子光谱仪 (ICP AES)完成 .REE含量依北美页岩组合(NASC)标准化 ,并按log[3Cen/ ( 2Lan+Ndn) ]计算Ce异常值 .以全岩Ce异常作为海平面变化的定量指标 ,识别出 5个明显的海平面升降旋回 ,发现多幕次黑色岩系与海侵事件严格对应 .鉴于同期黑色岩系的全球性分布和华南特定的古地理格局 ,提出华南早古生代多幕次黑色岩系的最小含氧层扩展成因模式 .

关键词：全岩铈异常古海洋学海平面变化早古生代

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云南武定早寒武世关山动物群棘皮动物化石

科学通报 2006年第11期51卷 1366-1368页

作者：胡世学罗惠麟侯蜀光 bernd-d.etrich erdtmann 云南省地质科学研究所 Technische Universitt Berlin d-13355 Berlin Germany

报道了云南早寒武世乌龙箐组关山动物群中新发现的始海百合类棘皮动物化石．关山动物群始海百合是目前所发现的最早的始海百合类之一,具腕、萼和柄,其萼板形态简单,无缝孔和瘤突,腕长,呈旋卷状,柄较长,柄与萼的长度之比较大．关山动物... 详细信息

报道了云南早寒武世乌龙箐组关山动物群中新发现的始海百合类棘皮动物化石．关山动物群始海百合是目前所发现的最早的始海百合类之一,具腕、萼和柄,其萼板形态简单,无缝孔和瘤突,腕长,呈旋卷状,柄较长,柄与萼的长度之比较大．关山动物群始海百合类棘皮动物的发现,不仅对研究棘皮动物的早期演化提供了新的线索和材料,而且对研究早期棘皮动物和始海百合类生态习性变迁也有着重要的意义．

关键词：云南早寒武世乌龙箐组关山动物群始海百合