中国恐龙蛋化石及其生态地层浅析

文章系统地对中国恐龙蛋化石的地理分布作了总结,并将恐龙蛋化石类型归纳为９科,１３属,２１种。在此基础上,着重分析了恐龙蛋化石古生态特征,分别从蛋化石的排列方式,恐龙产蛋的方式,不同类型蛋化石间及蛋化石与骨骼化石共生几方面作了探讨,并进一步阐述恐龙蛋化石在晚白垩世地层划分对比所具有的直接指示意义     

Analysis of fossil pigments from algae and bacteria in meromictic Lake Fidler, Tasmania, and its application to lake management

Lake Fidler is an ectogenic meromictic lake with a monimolimnion maintained by periodic incursions of brackish water from the lower Gordon River estuary. A dam across the middle reaches of the Gordon River has restricted these incursions of brackish water and meromictic stability has rapidly declined. A palaeolimnological study was carried in order to assess the historical development of meromixis and the impact of the dam on the microbiological communities in the lake. Fossil pigments in a 17 m sediment core were analysed using reverse phase high performance liquid chromatography (rp-HPLC) and mass spectrometry (MS). In addition, taphonomic studies of pigment production, deposition and degradation in the water column and surface sediments were used to identify planktonic and benthic pigment degradation processes and constrain the stratigraphic interpretation. Results comparing the pigment composition of pelagic sediment traps and littoral surface sediments indicated that the core from the centre of the lake would permit a historical reconstruction of planktonic bacterial and algal communities. Marked increases in prokaryotic pigments ca 3500 yr B.P. suggested the possible colonisation of a chemocline by phototrophic bacteria. Further changes in chlorophyll: carotenoid ratios and changes in relative abundances of both chlorophyll a and bacteriochlorophyll c derivatives also indicated that a change in the depositional environment had occurred; possibly due to altered stratification or anoxia. From this we infer the onset of either intermittent or permanent meromixis. Further increases in prokaryotic pigment abundance suggested that the present state of permanent meromixis was firmly established by 2070 ±50 ¹⁴C yr B.P., and diatom analysis confirmed the development of a stable mixolimnion. High resolution studies of the top 10 cm of sediments measured pigments in mean concentrations of 15.1 ng g^-1 with a mean S.D. of only 2.78 indicating little change in pigment abundance since the construction of the dam. Thus, Lake Fidler still retains most of the features of meromixis. However, evidence from nearby Lake Morrison and Sulphide Pool has shown that any further declines in meromictic stability will cause a rapid reversion to holomixis. Palaeolimnological evidence from the early stages of meromictic development of Lake Fidler suggests that such reversion to holomixis may not permanently eliminate all the microbiological communities, and that, given time, they may return and prosper with re-establishment of a suitable chemocline. These studies will guide recommendations for a management strategy to prevent the further decay of meromixis in the Gordon River lakes.     

福建省石炭纪─白垩纪古生物群主要特征

通过总结福建省石炭纪─白垩纪地层中及珊瑚、腕足、双壳、菊石、叶肢介和植物等门类的古生物化石组合特征,为省内石炭纪─白垩纪地层的划分、对比提供重要的依据。     

深海热液喷口生物群落的研究进展

深海热液喷口生物群落并不依赖光合作用获取能量,它们是一类独特的生物类型,其食物链的基础是化学合成细菌,这些细菌依靠喷口热液中的还原无机物氧化．利用CO。合成有机碳,它们共生于大个体动物的软组织或绍中,向寄主提供生存必需的有机碳。地质时期古热液喷口生物群落的研究还表明,该类生物群落在古生代（可能更早）即已出现。此外,现代热液喷口与古热液喷口生物群落的比较研究,在探索该生物群落乃至早期生命的起源、演化方面也取得了可喜进展。     

Eocene drill holes in cold-seep bivalves of Hokkaido, northern Japan

Four specimens of the thyasirid Conchocele bisecta (Conrad) and one small specimen of the vesicomyid Hubertschenckia ezoensis (Yokoyama), each with a drill hole made by a naticid gastropod, were found at a cold‐seep site in the upper Eocene Poronai Formation of Hokkaido. This is apparently the oldest record not only of drill holes, but also of predation scars, in a cold‐seep fauna. In addition, drilled vesicomyids are known from several Miocene cold‐seep sites in Japan. We suggest that the Eocene and Miocene chemoautotrophic bivalves were drilled only in the shallow‐water settings preferred by most naticids. The lack of drill holes in Oligocene chemoautotrophic bivalves in the northwestern USA suggests that this innovation, which allowed naticids to prey upon highly toxic bivalves, first appeared in the western Pacific during the Eocene.     

The geological significance of fossils in the coastal loess in the Bohai Straits and Liaodong Peninsula

Based on the analysis of the characteristics of the fossils (mollusks, Radiolaria, planktonic and benthicForaminifera and Ostracoda) found in the four loess profiles located respectively at Heishigou and Beizhuang Villages on Daheishan Island in the Miaodao Islands in the Bohai Straits, and Daweijia and Yujiawaizi Villages in Jinzhou County, Liaodong Peninsula, the distribution and abundance variation of the fossils in vertical profiles are studied, the source of coastal loess is probed and the relationship between loess deposition and paleoclimatic environment as well as sea-level changes is discussed.     

Transgressions of Late Cretaceous to Early Tertiary in Eastern China

ＴＲＡＮＳＧＲＥＳＳＩＯＮＳＯＦＬＡＴＥＣＲＥＴＡＣＥＯＵＳＴＯＥＡＲＬＹＴＥＲＴＩＡＲＹＩＮＥＡＳＴＥＲＮＣＨＩＮＡＱｉｕＳｏｎｇｙｕ，ＬｕＢｉｎｇｌｉ，ＣｈｅｎＹｏｎｇｃｈｅｎｇ（ＪｉｌｉｎＨｅａｄｑｕａｒｔｅｒｓＯｆＰｅｔｒｏｌｅｕｍＰｒｏｓｐ...     

珠江口及南海沉积物碳黑的放射性碳年龄

放射性碳同位素(14C)是含碳物质年代测定的有效手段,它的半衰期是5730年.研究了珠江口及南海沉积物碳黑的放射性碳年龄,碳黑样品采取化学氧化方法提取,用加速器质谱仪(AMS)测定珠江三角洲沉积柱中碳黑的放射性碳同位素剂量.研究结果表明,位于珠江口的钻孔3的碳黑的14C年龄是倒置的,邻近香港的钻孔30的碳黑14C年龄旱现老.新.老的趋势,而钻孔E2的碳黑的14C年龄则儿乎是不变的.碳黑的这种14C年龄的变化趋势与碳黑的来源相关,化石燃料来源的碳黑的增加使得碳黑的14C年龄偏老.     

湖北郧西白龙洞遗址骨化石表面痕迹研究

湖北省郧西县白龙洞古人类遗址属于中更新世早期,发掘出表面带有痕迹的骨化石标本。使用肉眼裸视观察法、低倍显微观察法、高倍显微观察法、三维扫描数字模型技术等多种观测分析法进行综合研究,鉴定出痕迹种类包括人工改造痕迹和其他动物改造痕迹。人工改造痕迹包括锤击痕迹、切割痕迹、砍斫痕迹、戳刺痕迹等,其中锤击痕迹主要出现在骨器表面(用于骨器制造),其他痕迹则出现在多种骨骼部位的残片上(可能由狩猎、屠宰、分割和剥皮行为产生)。动物改造痕迹包括食肉目动物啃咬痕、偶蹄目动物踩踏痕、啮齿目动物啃咬痕等。其中制造啃咬痕的啮齿目动物中,可能包括有豪猪、竹鼠和鼠科动物等。人工改造痕迹的研究对认识当时人行为模式提供了具体证据,如当时人对洞穴占据使用形式、骨质工具制造与使用、狩猎与分食行为(狩猎工具与剥皮技巧)等。本研究对其他动物改造痕迹也作了必要分析,如豪猪与鼠科动物的不同啃啮形态等。该遗址研究、鉴定出的多种痕迹标本,以及多种鉴定、分析方法的使用等,显示出古人类遗址中痕迹标本的复杂性,以及多种研究方法的必要性。三维扫描数字模型技术,是国内在该领域研究方法中的首次使用。     

辽西地区义县组昆虫化石及其生物地层、古生态学意义

作为热河昆虫群的重要组成部分,辽西地区义县组昆虫化石内容独特、丰富,共有49科83属,明显区别于同属热河昆虫群的大北沟组和九佛堂组,生物地层单位称为Epheeropsis trisetalis-Sinaeschnidia cancellosa组合,时代为晚侏罗世晚期-早白垩世早期.昆虫群反映了当时温暖而潮湿的气候环境及因地形不同引起的小气候的存在.