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Geoscience Frontiers 2013年第4期4卷 449-468页

作者： Gerald Hofer michael wagreich Stephanie Neuhuber Department of Geodynamics and Sedimentology.University of Vienna

Bulk rock geochemistry of 169 fine-grained sediment samples of the upper Cretaceous to Paleogene Gosau Group （Northern Calcareous Alps, Austria and Slovakia） fiom borehole and outcrop localities was performed to separate non-marine and marine deposits. Geochemical characteristics of different Gosau depositional systems, basins and sediment provenance using major-, trace-, and rare earth elements were also investigated. Geochemical proxies such as boron concentrations were tested for seeking the possibilities of paleosalinity indicators. Due to the [act that several pelagic sections are represented by extremely low boron contents, B/AI＊ ratios are recognized as more robust and differentiate reliably between marine （mean： 160 ± 34） and non-marine （mean： 133 ± 33） samples. Using statistical factor analysis, hemipelagic to pelagic samples flom the Gieghi_ibl Syncline and Slovakian equivalents can be differentiated from marginal-marine to non-marine samples from the Grtinbach and Glinzendorf Syncline related to terrigenous （SiO2, AI203, K20, Th, Rb, Zr and others） and pelagic indicative elements （CaO, St, TOT/C and B/AI＊）. A clear indication for ophiolitic provenance is traced by high amounts of chromium and nickel. Only non-marine successions of the Glinzendorf Syncline show higher Cr and Ni concentrations （up to 250 and 400 ppm, respectively） and enriched Cr/V and Y/Ni ratios trending to an ultramafic source.

关键词： Gosau GroupGeochemistryPre-Neogene Vienna BasinBoronFactor analysisProvenance

Special Topic： Cretaceous greenhouse palaeoclimate and sea-level changes

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Science China Earth Sciences 2017年第1期60卷 1-4页

作者： XiuMian HU michael wagreich Benjamin SAMES State Key Laboratory of Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University China Department of Geodynamics and Sedimentology Center for Earth Sciences University of Vienna Austria

Earth＇s climate has oscillated between greenhouse （warm） and icehouse （cold） modes throughout Earth history. At present, Earth is in the midst of an icehouse climate interval, despite the anthropogenic contribution to global warming and sea-level rise due to industrialization during the past two centuries. This led to a dramatic increase in atmospheric CO2, mainly caused by the extensive burning of fossils fuels. The Cretaceous （145 to 66 million years ago） is the youngest prolonged greenhouse climate interval in the Phanerozoic, marked by very high global mean temperatures with some extreme warming peaks （＇hothouse＇ or ＇supergreenhouse＇）, largely absence of permanent continental ice sheets, a mean global sea-level having been some 250 m higher than that of today, and levels of carbon dioxide 4 to 10 times higher than those of the pre-industrial era. If temperature will continue to rise as quickly as in the last three decades, we are close to being at the cusp to a new greenhouse climate interval facing quickly rising global sea-level and reaching atmospheric CO2 levels of the ＇Cretaceous supergreenhouse＇ in about the years 2190-2260 （Hay, 2011）. Evidence from Earth＇s history indicates that glacial-interglacial climate mode changes as well as past sea-level changes such as in the Cretaceous greenhouse occurred at rates orders of magnitude slower than observed at present. The recent rise in global sea-level in response to rising levels of atmospheric greenhouse gases, the associated global warm- ing, and the waning of continental ice shields is a primary concern for human society. To predict future sea-levels we need a better understanding of the record of past sea-level changes, especially in the greenhouse palaeoclimate modes. Therefore, understanding the Cretaceous palaeoclimate is essential for a more accurate prediction of future global climate, sea-level rise and environmental changes in a prospective ＇Cretaceous-like＇ greenhouse Earth.

关键词： greenhouse Cretaceous warming anthropogenic despite throughout

Orbital cyclicity in sedimentary sequence and climatic indications of C-O isotopes from Lower Cretaceous in Qingxi Sag, Jiuquan Basin, NW China

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Geoscience Frontiers 2019年第2期10卷 467-479页

作者： Siding Jin Haiyang Cao Hua Wang michael wagreich Sylvain Richoz State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology College of Energy Resources Chengdu University of Technology Institute of Sedimentary Geology Center for Post-doctoral StudiesChengdu University of Technology Key Laboratory of Tectonics and Petroleum Resources China University of Geosciences Department of Geodynamics and Sedimentology University of Vienna Institute of Earth Sciences NAWI GrazUniversity of Graz

Sedimentary deposits of the Lower Cretaceous Xiagou Formation form the most significant potential hydrocarbon reservoirs in the Qingxi Sag, Jiuquan Basin(NW China). Zircon U-Pb ages of the dated basalts at the top of the Xiagou Formation give an isochron age of 115.6 Ma, and the sedimentation interval of the Xiagou Formation was speculated to range from about 125/124 Ma to 115 Ma based on paleontological research and stratigraphic correlation analysis. Here we use GR logging data as a palaeoenvironmental and palaeoclimatic proxy to conduct a detailed cyclostratigraphic study of five selected wells. Power spectra, evolutionary fast Fourier transformation and wavelet analysis all reveal significant sedimentary cycles in the Xiagou Formation. The ratios of cycle wavelengths in these stratigraphic units are 33.82 m : 7.91 m : 3.06 m : 1.79 m, which is similar to the ratio of orbital targets of 20 : 5 : 2 : 1. The ratio of 20 : 5 : 2 : 1 is interpreted as Milankovitch cycles of 405 kyr long eccentricity,100 kyr short eccentricity, 37 kyr obliquity, and 22 kyr precession cycles respectively. A high-resolution astronomical time scale is constructed by tuning the stratigraphy into target curves of orbital cycles respectively. Based on the astronomical time scale, the absolute ages of 55 samples were estimated,which are used for subsequent stable carbon and oxygen isotope stratigraphy analysis. The analysis results of the five studied wells in the Qingxi Sag indicate:(1) a negative trend of δ^(13)C values upwards in the Xiagou Formation, and(2) negative δ^(18)O values with a positive trend upwards. Both relatively heavy values and pronounced covariances of δ^(13)C values and δ^(18)O values indicate an arid-evaporationcontrolled climate during the sedimentary period of the Lower Cretaceous Xiagou Formation, Qingxi Sag, Jiuquan Basin. Moreover, positive covariances of SQK_1g_(2+3) indicate extremely high temperature, and negative covariances of SQK_1g_1 indicate a relatively l

关键词： Jiuquan Basin Qingxi Sag Xiagou Formation Orbital cyclicity Stable isotope

Climate-environmental Deteriorations in a Greenhouse Earth System:Causes and Consequences of Short-Term Cretaceous Sea-Level Changes(a Report on IGCP 609)

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Acta Geologica Sinica(English Edition) 2019年第S1期93卷 144-146页

作者： michael wagreich Benjamin SAMES HU Xiumian University of Vienna 1090 ViennaAustria Nanjing University School of Earth Sciences and Engineering210023 NanjingChina

Anthropogenic global warming and resulting sea-level rise in response to enhanced atmospheric greenhouse gases and melting of the Earth’s continental ice shields have become issues of continuously growing interest for the scientific community as well as the public,pointing to threads of societies in a future greenhouse Earth System.

关键词： sea-level change greenhouse Cretaceous

A Periglacial Palaeoenvionment in the Upper Carboniferous-Lower Permian Tobra Formation of the Salt Range,Pakistan

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1063-1078页

作者： Irfan U.JAN Shahid IQBAL Sarah J.DA VIES Jan A.ZALASIEWICZ michael H.STEPHENSON michael wagreich Muhammad HANEEF Muhammad HANIF Sajjad AHMAD National Centre of Excellence in Geology University of Peshawar Department of Earth Sciences Quaid-i-Azam University Islamabad Department of Geodynamics and Sedimentology University of Vienna Department of Geology University of Leicester British Geological Survey Department of Earth Sciences Comsats Institute of Technology Abbottabad Department of Geology University of Peshawar

The Upper Carboniferous-Lower Permian （Upper Pennsylvanian-Asselian） Tobra Formation is exposed in the Salt and Trans Indus ranges of Pakistan. The formation exhibits an alluvial plain （alluvial fan-piedmont alluvial plain） facies association in the Salt Range and Khisor Range. In addition, a stream flow facies association is restricted to the eastern Salt Range. The alluvial plain facies association is comprised of clast-supported massive conglomerate （Gmc）, diamictite （Dm） facies, and massive sandstone （Sm） iithofacies whereas the stream flow-dominated alluvial plain facies association includes fine-grained sandstone and sUtstone （Fss）, fining upwards pebbly sandstone （Sf）, and massive mudstone （Fro） lithofacies. The lack of glacial signatures （particularly glacial grooves and striations） in the deposits in the Tobra Formation, which are, in contrast, present in their time-equivalent and palaeogeographically nearby strata of the Arabian peninsula, e.g. the Al Khlata Formation of Oman and Unayzah B member of the Sandi Arabia, suggests a pro-to periglacial, i.e. glaciofluvial depositional setting for the Tobra Formation. The sedimentology of the Tobra Formation attests that the Salt Range, Pakistan, occupied a palaeogeographic position just beyond the maximum glacial extent during Upper Pennsylvanian-Asselian time.

关键词： Pennsylvanian-Asselian Tobra Formation Salt Range Khisor Range glaciofluvial Pakistan

奥地利Gosau群Bibereck组Campanian早期海水变深序列的地层学和地球化学(英文)

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地学前缘 2005年第2期12卷 123-131页

作者： michael wagreich Stephanie NEUHUBER Department of Geological Sciences University of Vienna Althanstrasse 14 A-1090 Vienna AustriaDepartment of Geological Sciences University of Vienna Althanstrasse 14 A-1090 Vienna Austria

Schmidsippl剖面位于奥地利北钙质阿尔卑斯构造带内Gosau群典型地区。剖面出露的Bibereck组记录了一个海侵和沉积区海水变深过程。Bibereck组之下是Santonian晚期Hoclamoos组(Santlkalkbank段)，主要为砂质、粉砂质灰色生物扰动构造发... 详细信息

Schmidsippl剖面位于奥地利北钙质阿尔卑斯构造带内Gosau群典型地区。剖面出露的Bibereck组记录了一个海侵和沉积区海水变深过程。Bibereck组之下是Santonian晚期Hoclamoos组(Santlkalkbank段)，主要为砂质、粉砂质灰色生物扰动构造发育的泥灰岩，含少量双壳类碎片。Hochmoos组之上为灰色泥灰岩和泥灰质灰岩。Bibereck组下部显示变深到近滨-远滨过渡带区域；向上，泥灰岩指示细粒泥质远滨沉积，水深大致50～150m；之上出现浮游有孔虫含量超过90％的泥灰质灰岩，代表着半深海沉积环境。生物地层数据显示采样层位整体位于浮游有孔虫asymetrica-elevata带，由Globotruncanita elevata和Dicarinella asymetrica的共同出现来界定。钙质超微化石Calculites obscurus、Lucianorhabdus cayeuxii、Arkhangelskiella cymbi formis的出现指示属于钙质超微化石带CC17b／UC12，相当于Campanian初期。地层深度剖面上，Ca／Al比值和Catot含量显示海水来源的Ca在0～5m地层内几近于零，向上快速增加；(Fe／Al)／碳酸盐显示两个峰值，代表更还原条件，分别位于4m和10m位置；K／Al比值的下降被解释为更潮湿气候条件；剖面上部Ba含量的增加显示向更低原始生产条件的变化；陆源矿物在剖面7m以下保持稳定，之上一直到剖面顶部不断下降。生物地层数据表明在约50万年短暂的时间间隔内水深由几米深浅水环境变深为800～1500m深半深海环境。地球化学数据显示在海侵过程中出现两个海平面变化波动过程。这些数据为与上覆大洋红层进行对比提供了基础。

关键词： Campanian Ca/Al比值海平面变化海水变深序列奥地利