安徽省嘉山县官山沉积型坡缕石的矿物学研究

官山坡缕石矿物为典型的沉积成因,结晶程度低、化学成分较复杂,以富Fe_2O_3为特征。矿物在380～580℃热脱水过程中TG曲线近于连续,因此,推测其存在结晶水(OH_2)和结构水(OH)同时脱失的温度区域。X射线粉晶衍射数据中,矿物的(121)、(161)面网衍射不同程度地发生分裂,应属于单斜晶系,但单斜角β近于90°。矿物红外光谱特征和摩叶根标谱类似,只是由于Mg~(2+)、Al~(3+)等八面体阳离子占位率的变化引起部分振动频数的微小飘移。     

Guanling Biota: A Marker of Triassic Biotic Recovery from the end-Permian Extinction in the Ancient Guizhou Sea

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.     

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

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.     

论淮南生物群

淮南生物群 (Huainan Biota)产于安徽淮南地区新元古代淮南群中 ,由宏观藻类 Chuaria- Tawuia组合和蠕形动物 Pararenicola- Paleolina组合组成 ,可与加拿大西北麦肯齐山新元古代小达尔群 (L ittle Dal Group)小达尔生物群 (L ittle Dal Biota)对比 ,为新元古代大冰期前的一个特有生物群落 ,地质时代为前震旦纪 (本文的震旦纪即目前的南华纪至震旦纪 ) ,时限约为 85 0— 75 0 Ma,从而将前人所定淮南生物群为青白口纪至震旦纪的时代结论修订为前震旦纪。这对我国乃至国际上新元古代地层层序的重新划分与对比 ,以及新元古代早期生命演化研究等都具有重大的理论意义和实际价值。文中还着重论述了淮南生物群的组合特征和特定的生物发展阶段 ,而区别于青白口纪和震旦纪的生物群落 ,并通过洲际对比 ,讨论了淮南生物群的地层学意义     

黔东北震旦纪陡山沱晚期庙河型生物群的生态特征及埋藏环境初探

贵州省东北部江口县桃映震旦纪陡山沱组上部发现的庙河型生物群,包括宏体藻类、可能的后生动物、遗迹化石以及其它生物化石等,进一步证实这类宏体生物群在扬子地区震旦纪陡山沱晚期有较为广泛的分布。通过与鄂西庙河生物群、皖南蓝田植物群的对比,震旦纪陡山沱晚期宏体生物群的生活环境主要为开阔浅海向台缘斜坡相过渡地带。通过对黔东北庙河型生物群的研究,认为陡山沱晚期的宏体生物群为以营固着生活方式为主,生活于透光性较好、具有一定水动力条件和一定含氧量的相对静水贫氧浅海环境;其固着基底为富含水份的未固结的粥性-软质基底。这些宏体生物群多呈半漂浮状竖立于海底,构成初步的“海底草原”,为生物群中依赖一定氧而生活、生长和繁殖的动物提供了必要的支持。生物死亡后,大部分生物躯体倒伏于沉积物表面,在贫氧和较快沉积速率的沉积环境中,生物遗体被较好保存,并很快被沉积物所埋藏。随着沉积物的增厚,生物遗体被完全封闭,导致生物遗体腐烂和分解过程终止,使其得以很好保存。较快的沉积速率、贫氧和相对平静水体的环境是生物群得以很好保存的重要因素。     

中国水生蜥与潜龙名称合法性之争

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。     

Siliciclastic and volcaniclastic influences on equatorial carbonates: insights from the Neogene of Indonesia

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.     

中国东北区中生代生物群特征简述

概要的总结了东北区中生代地层中古生物群，以及它们在岩石地层单位中的分布，借以说明岩石地层的时代，为地层多重划分对比提供了依据。     

贵州台江中寒武世凯里生物群古生态研究

凯里生物群是世界三大布尔吉斯页岩型生物群之一。本文通过古生物个体埋藏保存情况、古生物个体生态学、沉积学和地球化学等的研究和分析,认为凯里生物群中大部分分子是从异地搬运到陆棚环境埋藏的。同时,提出了凯里生物群的埋藏机理模式和生态复原图。     

试论宏体植物的早期演化

概述了地史早期宏体植物化石的记录。从细胞群体到组织-器官构造有大约11 亿年的漫长进化史。蓝田植物群和庙河生物群标志着震旦晚期(大约7-5.4 亿年间)发生了宏体植物演化史上的一次大辐射,非矿化、弱矿化、和矿化的高级藻类出现。寒武纪发生了另一次辐射。非矿化藻类是最有发展前途的类群,可能直接导致了维管植物的出现。