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Progress in Natural Science:Materials International 2004年第1期14卷 92-97页

作者： Michael STEINER 13355 Berlin ackerstrasse 71～76 Germany Technische Universitt Berlin Sekr.ACK 14

The Xiaoyang section, located in Zhenba County of Shaanxi Province, is important both for documenting the biodiversity of the Qiongzhusian Stage (Lower Cambrian) and for analyzing lithofacies biofacies links in carbonate depositing environments on the Yangtze Platform. The skeletal fossils from the Xihaoping Member, including linguloid valves, cambroclavid and chancelloriid sclerites, genal and occipital spines of polymerid trilobites, and tubular fossils, are described here as the Eoobolus Cambroclavus fauna, which mainly occurred in peritidal environments. The fossils from the argillaceous limestones of the lower Shuijingtuo Formation, containing lingulate brachiopods, eodiscoid trilobites, bivalved arthropods, microdictyoniid sclerites and siliceous sponge spicules, are regarded as the Palaeobolus Hupeidiscus Kunmingella fauna, which presumably lived in subtidal or deeper water environments. The faunal diversity in the Xihaoping Member is lower than that in the lower Shuijingtuo Formation. The investigations of the skeletal fossil assemblages from carbonate lithofacies in southern Shaanxi will significantly contribute to a detailed documentation of the biodiversity during the Qiongzhusian interval on the Yangtze Platform and add new knowledge on the Cambrian bioradiation.

关键词： skeletal fauna Xihaoping Member Shuijingtuo Formation Lower Cambrian Shaanxi

Improvements in Inversion of Magnetic Resonance Exploration-Water Content, Decay Time, and Resistivity

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Journal of China University of Geosciences 2009年第3期20卷 592-605页

作者： Ugur Yaramanci Mike Müller-Petke Leibniz Institute of Applied Geophysics Stilleweg 2 Hannover D-30655 Germany Berlin University of Technology Ackerstrasse 71-76 Berlin D-13355 Germany

In this review article, we present recent developments and improvements in magnetic resonance sounding （MRS）, a newly established geophysical exploration method that provides unique information about hydrogeophysical properties due to its direct sensitivity to hydrogen protons and proton dynamics. Starting with the most sophisticated and complete MRS formulation, we give a detailed view on how to solve the equation, i.e., inverting exactly for all model parameters： water content, decay time, and resistivity. Giving a short review of general inversion schemes used in geophysics, the special properties of MRS inversion are evaluated and the development of MRS inversion over recent years is shown. We present the extension of MRS to magnetic resonance tomography （MRT）, i.e., the extension to two-dimensional investigations and appropriate inversions. Finally, we address restrictions, limitations, and inconsistencies as well as future developments.

关键词： magnetic resonance sounding (MRS) magnetic resonance tomography (MRT) inversion modeling water content decay time resistivity.

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.

Microstructure and functional morphology of the Early Cambrian problematical fossil Rhombocorniculum

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Progress in Natural Science:Materials International 2003年第11期 31-35页

作者： Michael STEINER 13355 Berlin ackerstrasse 71～76 Germany Technische Universitt Berlin Sekr.ACK 14

Rhombocorniculum cancellatum from the Lower Cambrian of southern Shaanxi Province (South China) is represented by the dextral and sinistral tooth-like sclerites (both in nearly equal numbers), indicating that the body plan of the organism with these sclerites probably was bilaterian. The main feature of the microstructure of the sclerites is the presence of longitudinally arranged, mutually contiguous hollow tubules, the shared walls consisting of microcrystalline apatite. In transverse cross sections, the sclerite wall mainly exhibits a spongy structure, with pore size decreasing adapically. Functional morphological analysis indicates that the sclerites serve as a defensive rather than a grasping function.

关键词： Early Cambrian Rhombocorniculum microstructure functional morphology.

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煤系岩石物理力学参数与声波速度之间的关系

地球物理学报 2006年第5期49卷 1505-1510页

作者：孟召平张吉昌 Joachim Tiedemann 中国矿业大学资源与地球科学系 Applied Geoscience Institute of Technical University Berlin ackerstrasse 76 13355 BerlinGermany

通过超声-时间动态测试方法系统地分析了煤系沉积岩石纵波和横波速度,计算了煤系岩石动弹性力学参数,同步测试了煤系岩石的静态力学参数,建立了煤系沉积岩石动弹性力学参数与静弹性力学参数之间和煤系岩石物理力学参数与其声波速度之间... 详细信息

通过超声-时间动态测试方法系统地分析了煤系沉积岩石纵波和横波速度,计算了煤系岩石动弹性力学参数,同步测试了煤系岩石的静态力学参数,建立了煤系沉积岩石动弹性力学参数与静弹性力学参数之间和煤系岩石物理力学参数与其声波速度之间的定性定量关系.研究结果表明,煤系岩石的动弹性模量与岩石的纵波或横波速度具有很好的正相关关系,而与泊松比不具有这种正相关关系.煤系岩石的动弹性模量要大于其静弹性模量,而动泊松比要小于其静泊松比,它们之间呈线性相关关系.煤系岩石密度、单轴抗压和抗拉强度与其纵波或横波速度之间也呈正相关关系,它们分别服从二次函数、指数函数和线性函数分布.

关键词：煤系岩石声波速度物理力学参数

早寒武世疑难化石Rhombocorniculum的刺壁微细结构及形态功能分析

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自然科学进展 2003年第8期13卷 881-884页

作者：李国祥朱茂炎 Michael Steiner 中国科学院南京地质古生物研究所 Technische Universitat Berlin Sekr.ACK 14Ackerstrasse 71-7613355 BerlinGermany

通过研究陕南早寒武世疑难化石Rhombocorniculum cancellatum,首次发现其骨片主要由左型和右型两类刺体组成,两类刺体在样品中数量相近,指示它们为某类两侧对称的动物所有,研究发现其刺壁主要由中空的纤状管体组成,纤管的壁由微晶磷灰... 详细信息

通过研究陕南早寒武世疑难化石Rhombocorniculum cancellatum,首次发现其骨片主要由左型和右型两类刺体组成,两类刺体在样品中数量相近,指示它们为某类两侧对称的动物所有,研究发现其刺壁主要由中空的纤状管体组成,纤管的壁由微晶磷灰石组成,相邻纤管之间相互共壁;横断面观察呈多孔状,管孔在刺体基部断面直径较大,向顶端变小,纵断面可见纤管的延伸方向与刺体纵轴一致,刺壁微细结构及刺体的表面装饰皆不同于原牙形刺化石,难以解释为动物的捕食器官(刺),而可能为某类后生动物躯体表面的、起着防御功能的外骨骼。

关键词：早寒武世生物化石刺壁微细结构形态功能骨骼化石刺体

论中国早寒武世原牙形类和牙形状化石--分类评述和地层意义

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微体古生物学报 2008年第4期25卷 307-315页

作者：钱逸李国祥朱茂炎 Michael STEINER Bernd-D ERDTMAMN 冯伟民蒋志文中国科学院南京地质古生物研究所南京210008 Technische Universitat Berlin Sekr.ACK14Ackerstrasse 71-76D-13355 BerlinGermany 云南大学云南省古生物研究重点实验室昆明650011

原牙形类和牙形状化石是早寒武世微小骨骼化石中非常特征的一个类群。自二十世纪70年代以来,这些齿状的微型磷质骨片化石在中国下寒武统含小壳化石地层中被大量发现,据统计已描述有25属52种。通过文中的评述和讨论,证实其中的一些属种... 详细信息

原牙形类和牙形状化石是早寒武世微小骨骼化石中非常特征的一个类群。自二十世纪70年代以来,这些齿状的微型磷质骨片化石在中国下寒武统含小壳化石地层中被大量发现,据统计已描述有25属52种。通过文中的评述和讨论,证实其中的一些属种是次异名或属于无效的分类名称,还有一些在归属上尚存在疑问。通过对原牙形类和牙形状化石定义的讨论,将先前指定为原牙形类的13个属进行了分类评述。表明其中的5个属是次异名,还有2个属是未知的节肢动物。其它的12个牙形状化石属中也有5个属是次异名,它们不仅显示了有多种动物亲缘的牙形状形态,而且大多属于绝灭生物,只有Beshtashella和Paraformitchella(=Beshtashella)被指定为软体动物。文中还简要地讨论了大多数属的时空分布,包括3个阶段的原牙形类地层分布,这不仅具有划分对比地层的意义,而且还反映了原牙形类的演化趋势。

关键词：原牙形类牙形状化石小壳化石早寒武世中国

Novel soil quality indicators for the evaluation of agricultural management practices:a biological perspective

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Frontiers of Agricultural Science and Engineering 2020年第3期7卷 257-274页

作者： Giulia BONGIORNO Soil Biology Group Wageningen University and Research6700 AA WageningenThe Netherlands Department of Soil Science Research Institute of Organic Agriculture(FiBL)Ackerstrasse 1135070 FrickSwitzerland

Developments in soil biology and in methodsto characterize soil organic carbon can potentially delivernovel soil quality indicators that can help identifymanagement practices able to sustain soil productivityand environmental resilience. This work aimed atsynthesizing results regarding the suitability of a range ofsoil biological and biochemical properties as novel soilquality indicators for agricultural management. The soilproperties, selected through a published literature review,comprised different labile organic carbon fractions [hydrophilicdissolved organic carbon, dissolved organic carbon,permanganate oxidizable carbon (POXC), hot waterextractable carbon and particulate organic matter carbon],soil disease suppressiveness measured using a Pythium-Lepidium bioassay, nematode communities characterizedby amplicon sequencing and qPCR, and microbialcommunity level physiological profiling measured withMicroResp™. Prior studies tested the sensitivity of each ofthe novel indicators to tillage and organic matter additionin ten European long-term field experiments (LTEs) andassessed their relationships with pre-existing soil qualityindicators of soil functioning. Here, the results of theseprevious studies are brought together and interpretedrelative to each other and to the broader body of literatureon soil quality assessment. Reduced tillage increasedcarbon availability, disease suppressiveness, nematoderichness and diversity, the stability and maturity of thefood web, and microbial activity and functional *** matter addition played a weaker role in enhancingsoil quality, possibly due to the range of composition of theorganic matter inputs used in the LTEs. POXC was theindicator that discriminated best between soil managementpractices, followed by nematode indices based on functionalcharacteristics. Structural equation modeling showsthat POXC has a central role in nutrient retention/supply,carbon sequestration, biodiversity conservation, erosion control an

关键词： labile carbon long-term field experiments organic matter addition soil biological indicators tillage

全球下奥陶统-中奥陶统界线层型候选剖面——宜昌黄花场剖面研究新进展

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地层学杂志 2005年第B11期29卷 467-489,i0003-i0008页

作者：汪啸风 Stouge S．陈孝红李志宏王传尚 ErdtmannB．-D．曾庆銮周志强陈辉明张淼徐光洪宜昌地质矿产研究所湖北宜昌443003 Geological Museum University of Copenhagen 1350 Oster Volgade 5-7 Copenhagen K Denmark China Geoscience Research Center Technical University Berlin Ackerstrasse 71 D-13355 Berlin Germany

湖北宜昌黄花场剖面是我国奥陶系大湾阶的界线层型剖面,高精度生物地层以及岩石、层序地层和碳同位素地球化学的综合研究表明,该剖面完全符合关于建立全球下奥陶统-中奥陶统界线(即奥陶系第三个尚待正式命名的阶)界线层型剖面和点位(GS... 详细信息

湖北宜昌黄花场剖面是我国奥陶系大湾阶的界线层型剖面,高精度生物地层以及岩石、层序地层和碳同位素地球化学的综合研究表明,该剖面完全符合关于建立全球下奥陶统-中奥陶统界线(即奥陶系第三个尚待正式命名的阶)界线层型剖面和点位(GSSP)的条件。建议以该剖面牙形石Baltoniodus?triangularis的首现层位,作为划分全球下奥陶统-中奥陶统界线的GSSP。所建议的GSSP交通方便,位于距宜昌市北北东22km的公路旁,地层出露完美无缺,界线生物层位于大湾组下段SHod-16层底部,距大湾组底部10.57m;界线上下发育了B.?triangu-laris的完整演化序列,并伴生有极好的Baltoniodus、Trapezognathus、Periodon和Microzarkodina等牙形石属种演化序列来作为佐证;界线之上0.2m所出现的世界广布的Microzarkodina abellum可作为划分此界线的辅助标志。界线生物层位于低位海侵序列之中,界线之下0.6m处所显示的从高位到低位的层序转换面和碳同位素最大偏移,与全球此时所发生低位事件密切相关,可作为识别该界线的物理和化学标志。所建议的界线生物层与笔石Azygograptus suecicus生物带上下组合之间的界线接近,与几丁虫***生物带底界几乎一致,因此,所建议的界线易于在全球,无论浅水碳酸盐相、还是深水笔石相,识别和进行精确对比。同样的生物组合序列和层序及碳同位素异常亦在黄花场剖面之北5km的陈家河(即大坪)剖面得到了验证.

关键词：下奥陶统-中奥陶统界线界线层型剖面和点位(GSSP) 黄花场剖面宜昌湖北牙形石笔石几丁虫