Siliciclastic and volcaniclastic influences on equatorial carbonates: insights from the Neogene of Indonesia   总被引：5，自引：0，他引：5  

Moyra E. J. Wilson  Stephen W. Lokier† 《Sedimentology》2002,49(3):583-601

ABSTRACT In active tectonic areas of humid equatorial regions, nearshore shallow‐water environments are commonly sites of near‐continuous siliciclastic influx and/or punctuated volcaniclastic input. Despite significant clastic influence, Neogene carbonates developed in SE Asia adjacent to major deltas or volcanic arcs, and are comparable with modern mixed carbonate–clastic deposits in the region. Research into delta‐front patch reefs from Borneo and fore‐arc carbonate platform development from Java is described and used to evaluate the effects of siliciclastic and volcaniclastic influx on regional carbonate sedimentation, local changes in carbonate‐producing biota and sequence development. Regional carbonate development in areas of high siliciclastic or volcaniclastic input was influenced by the presence of antecedent highs, changes in the amounts or rates of clastic input, delta lobe switching or variations in volcanic activity, energy regimes and relative sea‐level change. A variety of carbonate‐producing organisms, including larger benthic foraminifera, some corals, coralline algae, echinoderms and molluscs could tolerate near‐continuous siliciclastic or volcaniclastic influx approximately equal to their own production rates. These organisms adopted various ‘strategies’ for coping with clastic input, including a degree of mobility, morphologies adapted to unstable substrate inhabitation or shedding sediment, and shapes adapted to low light levels. Local carbonate production was also affected by energy regime, clastic grain sizes and associated nutrient input. Clastic input influenced the inhabitable depth range for photoautotrophs, the zonation of light‐dependent assemblages and the morphology and sequence development of mixed carbonate–clastic successions. This study provides data on the dynamic interactions between carbonate and non‐carbonate clastic sediments and, when combined with information from comparable modern environments, allows a better understanding of the effects of siliciclastic and volcaniclastic influx on carbonate production.  相似文献   

First report on Guanshan Biota(Cambrian Stage 4) at the stratotype area of Wulongqing Formation in Malong County,Eastern Yunnan,China     

Feiyang Chen  Zhifei Zhang  Marissa J.Betts  Zhiliang Zhang  Fan Liu 《地学前缘(英文版)》2019,10(4):1459-1476

Exceptionally preserved fossils,such as those from Cambrian Burgess Shale-type fossil-Lagerstatten are critical because of their unique contributions to knowledge of the phylogenetic radiation and palaeoecological expansion of metazoans during the Cambrian explosion.Critically,these deposits provide information that is usually unobtainable from shelly and skeletonized fossils alone.The Guanshan Biota(Cambrian Series 2,Stage 4)in the Yunnan Province of South China,has produced abundant and diverse,exquisitely preserved fossils that often retain soft tissues and organs.To date,most fossils from the Guanshan Biota have been collected from localities such as Gaoloufang and Gangtoucun,which have become inaccessible due to new urban expansions and constructions of residential buildings.Here we present the first report of soft bodied fossils from a new section at Kanfuqing,close to the Wulongqing village in Malong County,approximately 3 km east of the Wulongqing Formation stratotype section.Fossils retain soft morphology,and include brachiopods with delicate marginal setae,priapulids with well-preserved sclerites and vetulicolians with entire sections of body.In addition,this fauna includes rare occurrences of trilobites preserved with soft tissues replicated as pyrite pseudomorphs after weathering.This discovery represents an important palaeogeographical extension of soft-bodied fossils of the Guanshan fauna to the east of the Xiaojiang Fault(related to Tsinning tectonic movements ca.700 Ma).The fauna from the new Kanfuqing section is similar to that reported from the Wulongqing Formation west of the Xiaojiang Fault,and thus has significant implications for early Cambrian palaeogeography,faunal successions and palaeoenvironments of eastern Yunnan.  相似文献   

A conodont-based Middle Triassic age assignment for the Luoping Biota of Yunnan,China   总被引：5，自引：0，他引：5  

QiYue Zhang  ChangYong Zhou  Tao Lu  Tao Xie  XiongYing Lou  Wei Liu  YuanYuan Sun  JinYuan Huang  LaiShi Zhao 《中国科学D辑(英文版)》2009,52(10):1673-1678

The Luoping Biota consists of abundant and well-preserved marine fishes, reptiles, invertebrates, and plants. It occurs in the Middle Triassic Guanling Formation in Daaozi Village of Luoping County, Yun-nan Province, China. Based on conodonts, the Luoping Biota is determined to lie within the Nicoraella kockeli Zone, which is assigned to the Pelsonian substage of the Anisian.  相似文献   

Aliphatic and aromatic hydrocarbons in marine biota and coastal sediments from the Gulf and the Gulf of Oman     

Tolosa I  de Mora SJ  Fowler SW  Villeneuve JP  Bartocci J  Cattini C 《Marine pollution bulletin》2005,50(12):1619-1633

The composition and spatial distribution of aliphatic and polycyclic aromatic hydrocarbons (PAHs) were investigated in biota and coastal sediments from four countries surrounding the Gulf (Bahrain, Qatar, United Arab Emirates and Oman). The levels of total petroleum hydrocarbons (TPH), aliphatic unresolved mixture and PAHs in sediments and biota were relatively low compared to world-wide locations reported to be chronically contaminated by oil. Only in the case of the sediments collected near the BAPCO oil refinery in Bahrain, having concentrations of 779 μg g⁻¹ total petroleum hydrocarbon equivalents and 6.6 μg g⁻¹ ∑PAHs, can they be categorized as chronically contaminated. Some evidence of oil contamination was also apparent in sediments and bivalves around Akkah Head and Abu Dhabi in the UAE, and near Mirbat in Oman. Contaminant patterns in sediments and biota indicated that the PAHs were mainly from fossil sources, with the exception of the high PAH concentrations in sediments near the BAPCO refinery that contained substantial concentrations of carcinogenic PAH combustion products.  相似文献   

晚前寒武纪重要生物事件与事件地层界线     

丁莲芳 《地球科学与环境学报》1994,(4)

本文以生物绝灭及生物新生为主线,论述了国内外晚前寒武纪的几个主要生物出现事件——宏观藻类出现事件;后生软躯体动物出现与绝灭事件;带壳动物出现事件.通过这些生物事件,讨论了震旦-寒武系界线目前存在的几种看法,指出了震旦-寒武系界线选在A点是有足够的生物学基础的,同时此界线也是一条重要的事件地层界线.  相似文献   

Guanling Biota: A Marker of Triassic Biotic Recovery from the end-Permian Extinction in the Ancient Guizhou Sea   总被引：1，自引：0，他引：1  

Ryosuke MOTANI  Lars SCHMITZ 《《地质学报》英文版》2005,79(6):729-738

After a slow recovery from the end-Permian extinction during the Early Triassic and rapid radiation in the Middle Triassic, evolution of organisms reached a new peak phase in the Late Triassic. The Guanling Biota from the Wayao Member （conodont Paragondolella polygnathiformis Zone）, Falang Formation, Xinpu, Guanling County, Guizhou Province, southwestern China corresponds to this peak that marks the full recovery from the end-Permian extinction of marine ecosystems. The biota is of high diversity, containing well preserved and completely articulated skeletons of vertebrates comprising marine reptiles, fishes, and invertebrates including crinoids, ammonites, bivalves, and other fossils, and is one of the best examples of marine ecosystem records in life history. The fossil marine reptiles and crinoids are most significant in this biota, especially the marine reptiles, which provide an important link between the Triassic Pacific and Tethys, and between Triassic basal forms and the Jurassic-Cretaceous marine top predators. The most remarkable fossils are the large completely articulated ichthyosaur skeletons up to and more than 10 m, and the first recorded thalattosaurs and placodonts in China. Following our review, of the 17 named reptilian taxa the eight listed here are considered to be valid： three ichthyosaurs （Qianichthyosaurus zhoui Li, 1999; Guizhouichthyosaurus tangae Cao and Luo in Yin et al., 2000, Guanlingsaurus liangae Yin in Yin et al., 2000）, three thalattosaurs （Anshunsaurus huangguoshuensis Liu, 1999, Xinpusaurus suni Yin in Yin et al., 2000, Xinpusaurus kohi Jiang et al., 2004）, and two placodonts （Sinocyamodus xinpuensis Li, 2000, Psephochelys polyosteoderma Li and Rieppel, 2002）. Mixosaurus guanlingensis Cao in Yin et al., 2000 might be a junior synonym of Qianichthyosaurus zhoui Li, 1999, and Cymbospondylus asiaticus Li and You, 2002 and Panjiangsaurus epicharis Chen and Cheng, 2003 might be junior synonyms of Guizhouichthyosaurus tangae Cao and Luo in Yin et al., 2000. It needs to re-describe the holotypes after a complete preparation for clarifying the taxonomic status of Typicusichthyosaurus tsaihuae Yu in Yin et al., 2000, Xinpusaurus bamaolinensis Cheng, 2003, Neosinosaurus hoangi （Zhou in Yin et al., 2000）, Wayaosaurus geei Zhou in Yin et al., 2000, Wayaosaurus bellus Zhou in Yin et al., 2000 and Placochelys ？ minutus Yin and Luo in Yin et al., 2000.  相似文献   

辽西热河生物群箭蜓科昆虫新类群     

常建平  孙忠实 《世界地质》2006,25(2):105-112

描述了箭蜓科(Gomphidae)一新属种—宽翅辽宁澜箭蜓(Liaoninglanthus latusgen.et sp.nov.)及新属一未定种(Liaoninglanthus.sp.),还对义县光箭蜓(Liogomphus yixianensisRen et Gao,1996)进行了补充描述。化石全部采自辽西北票黄半吉沟义县组下部(晚侏罗世晚期—早白垩世)。  相似文献   

对西天山石炭纪地层及生物群的一些认识   总被引：1，自引：0，他引：1  

张建东 《新疆地质》2012,30(Z1):38-44

据前人资料结合1∶25万区调新资料研究成果,对西天山石炭纪典型岩石地层单位及时代、基本特征形成一些新的认识.对新疆北部石炭系腕足“管孔石燕动物群”、“安加拉植物群”及腕足“拟穆武贝动物群”的分布范围、生物区系意义进行总结和讨论.利用多年来西天山陆续发现的菊石化石,建立了本区7个石炭纪菊石带,并结合“R带”为主的菊石化石资料对西天山上、下石炭统年代界线进行讨论.  相似文献   

New Macroscopic Problematic Fossil from the Early Cambrian Yanjiahe Biota,Yichang, Hubei,China     

GUO Junfeng  LI Yong  HAN Huiping  OU Qiang  ZHOU Jianren  ZHENG Yajuan 《《地质学报》英文版》2012,86(4):791-798

Yanjiahella gen. nov., a distinctive fossil taxon from the Early Cambrian Yanjiahe Biota in Yichang, Hubei Province, is characterized by: 1) an overall body plan composed of a stalk and a calyx (also arms in some species); 2) a stalk with closely spaced, transverse wrinkles and a medial, longitudinal ridge; and 3) a calyx preserved with three-dimensional radiating striations, as well as a probable madreporite in some specimens. Three species that can be assigned to this genus, which are Y. ancarpa sp. nov., Y. monocarpa sp. nov., and Y. biscarpa sp. nov. Yanjiahella is comparable to certain echinoderm taxa in terms of morphology and some biological structures, which might indicate the early evolution and diversification of ancestral echinoderm lineages from the early Early Cambrian Yangtze Platform. The discovery of putative echinoderms in the Yanjiahe Biota provides significant clues about the origination and evolution of the deuterostome phylum Echinodermata.  相似文献   

中国水生蜥与潜龙名称合法性之争     

季燕南  王旭日  季强 《江苏地质》2014,38(1):12-16

热河生物群中有一种水生爬行动物,以长颈、长尾、小头颅为主要特征。在研究中,不同学者使用了不同的学名,构成了同物异名。简要回顾它的研究历史,主要讨论究竟哪一个学名是合法有效名称。根据国际动物学命名法规,认为中国水生蜥(Sinohydrosaurus)命名在先,是合法有效名称,而潜龙(Hyphalosaurus)为无效名称,应当废弃。  相似文献