检索结果-南通市图书馆

An Upward Shallowing Succession of Gravity Flow Deposits in the Early Cretaceous Lingshandao Formation,Western Yellow Sea

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2016年第4期90卷 1553-1554页

作者： YANG Renchao FAN Aiping HAN Zuozhen A.J.(Tom) van Loon College of Earth Science and Engineering Shandong University of Science and Technology geocom Consultants Valle del Portet

Objective Several well-exposed gravity flow deposits in the Early Cretaceous Lingshandao Formation provide a rare opportunity to study deep-water processes. The main objective of this work is to establish the spatial and temporal relationships between the various gravity flow deposits, and thus to establish their sequence stratigraphic patterns and depositional conditions.

关键词： An Upward Shallowing Succession of Gravity Flow Deposits in the Early Cretaceous Lingshandao Formation,Western Yellow Sea deep cycle

A new 'superassemblage' model explaining proximal-to-distal and lateral facies changes in fluvial environments,based on the Proterozoic Sanjauli Formation(Lesser Himalaya,India)

在线全文

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2016年第4期5卷 391-408页

作者： Ananya Mukhopadhyay Priyanka Mazumdar A.J. (Tom) van Loon Department of Earth Sciences Indian Institute of Engineering Science & Technology Shibpur Howrah West Bengal 711103 India geocom Consulting Valle del Portet 17 03726 Benitachell Spain

Facies analysis of fluvial deposits of the Proterozoic Sanjauli Formation in the Lesser Himalaya was combined with an architectural analysis. On this basis, a model was developed that may be applied to other fluvial systems as well, whether old or recent. The new model, which might be considered as an assemblage of previous models, explains lateral variations in architecture and facies but is not in all respects consistent with the standard fluvial models. The Sanjauli fluvial model is unique in that it deals with lateral facies variations due to shifts of the base-level along with fluctuations in accommodation space owing to changes in palaeoclimate.

关键词： Ftuvial model Braided river Sanjauli Formation Simta Basin Proterozoic Lesser Himalaya India

Siliceous Cementation of Chlorite-Coated Grains in the Permian Sandstone Gas Reservoirs,Ordos Basin

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2017年第3期91卷 1147-1148页

作者： FAN Aiping YANG Renchao LI Jinbu ZHAO Zhongjun A.J.(Tom) VAN LOON College of Earth Science and Engineering Shandong University of Science and Technology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Institute of Sulige Gas Field Changqing Oilfield CompanyPetrochina geocom Consultants

Objective It has long been controversial that whether authigenic chlorite coatings in sandstone reservoirs can prevent precipitation of siliceous cements. It is commonly believed that chlorite coatings （also called chlorite films, chlorite linings, or chlorite rims） may prevent quartz overgrowth, and thus help the preservation of original pores in sandstone reservoirs. Recently, however, this assumption has been challenged by reservoir geologists. This dispute cannot be solved by mere analysis of thin sections, nor by chemical equations and diagenesis analysis. The main objective of the present contribution is to shed light on this problem on the basis of sandstone samples from the Permian Shanxi and Shihezi Formations in the eastern part of the Sulige gas field, Ordos Basin in central China.

关键词： of on is for by Siliceous Cementation of Chlorite-Coated Grains in the Permian Sandstone Gas Reservoirs,Ordos Basin that

“The response of stromatolites to seismic shocks: Tomboliths from the Palaeoproterozoic Chaibasa Formation,E India”: Reply

在线全文

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2017年第3期6卷 235-241页

作者： A.J. (Tom) van Loon Rajat Mazumder Shuvabrata De College of Earth Science and Engineering Shandong University of Science and Technology geocom Consultants Department of Applied Geology Faculty of Science and EngineeringCurtin University Sarawak Geological Studies Division CSIR-National Geophysical Research Institute

Our contribution about a newly recognized sedimentological feature, which we called tombolith,has raised some comments on the etymology of the term, the assumed lack of field data, the usage of a term that has a special meaning in stratigraphy, the origin of the seismic shocks that played a role, so-called basic tenets, the origin of soft-sediment deformation structures, and the role of liquefaction. We argue that most comments result from an insufficiently thorough reading of our text, whereas some other remarks concern aspects that we did not deal with. Finally, several remarks are based on outdated literature and from insufficient knowledge of the regional geology.

关键词： Stromatolites Seismic shocks Palaeoproterozoic Singhbhum Craton Tomboliths India

A Marine or Continental Nature of the Deltas in the Early Cretaceous Lingshandao Formation--Evidences from Trace Elements

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2017年第1期91卷 367-368页

作者： YANG Renchao FAN Aiping HAN Zuozhen A.J.(Tom)VAN LOON College of Earth Science and Engineering Shandong University of Science and Technology Qingdao 266590 Shandong China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Qingdao 266071 China geocom Consultants Valle del Portet 17 03726 Benitachell Spain

Objective A succession with well-developed soft-sediment deformation structures and well-exposed gravity-flow deposits in the Early Cretaceous Lingshandao Formation has caused considerable controversy on whether the nondisputed deltaic environment was marine or *** dispute cannot be solved by mere sedimentological analysis and,moreover,too few fossils are present to be decisive.

关键词： Cr ppm Evidences from Trace Elements

The hyperpycnite problem: comment

在线全文

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2019年第3期8卷 314-320页

作者： A.J.(Tom) van Loon Heiko Hüneke Thierry Mulder geocom Consulting Valle del Portet 17 03726 Benitachell Spain College of Earth Science and Engineering Shandong University of Science and Technology Qingdao 266590 Shandong China Institute of Geography and Geology Greifswald University Greifswald Germany UMR CNRS EPOC University of Bordeaux Allee Geoffroy St-Hilaire 33615 Pessac Cedex France

A recent review article("The hyperpycnite problem") by Shanmugam(Journal of Palaeogeography 7(3):197–238,2018) in this journal has some shortcomings, comes to scientifically incorrect conclusions, and calls for student education in a way that would significantly diminish the students’ changes for a geological career. Having studied--and still studying--hyperpycnites in the field, it seems only appropriate to inform the readers of this journal about our concerns regarding the review article mentioned ***, the article by Shanmugam(Journal of Palaeogeography 7(3):197–238, 2018) is not a review paper but rather a comment, criticizing al researchers who have come to the conclusion, on the basis of both field research and theory,that hyperpycnal flows result in sediments(hyperpycnites) with characteristics that make it possible to distinguish them from deposits formed in another way. This is also the essence of Shanmugam’s comment: as he states himself, he is"an ardent critic of al genetic facies models".

关键词： review Shanmugam critic

The response of stromatolites to seismic shocks： Tomboliths from the Palaeoproterozoic Chaibasa Formation, E India

在线全文

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2016年第4期5卷 381-390页

作者： A.J. (Tom) van Loon Rajat Mazumder Shuvabrata De geocom Consultants Valle del Portet 17 03762 Benitachell Spain Department of Applied Geology Faculty of Science and Engineering Curtin University Sarawak CDT 250 98009 Miri Sarawak Malaysia Indian Institute of Science Education and Research Department of Earth and Environmental Sciences Bhopal By-pass Road Bhopal 462066 Madhya Pradesh India

It is demonstrated here for the first time how Palaeoproterozoic stromatolites survived seismic disturbance of their substrate. The stromatolites under study could have been cyanobacteria or any other photo-autotrophic microbes, which formed mats that covered a substrate of very fine-grained sandstones and mudstones of the Chaibasa Fm. in eastern India. The sediments represent a shelf environment. The local abundance of the stromatotites suggests that the tow-energy environment formed a suitable habitat. The common phases of tectonic quiescence were, however, occasionally interrupted by seismic shocks. These were sufficiently strong to deform the mat layers, the tower parts of which might already have been （semi-） consolidated. The mats became partly folded, partly faulted, and already consolidated parts of the stromatotite layers broke off. This can be deduced from the angular shapes of part of the broken-off fragments. It appears, however, that part of these fragments were stilt sufficiently soft to become rounded and deformed by rotting over the seafloor, probably under the influence of tidal currents. When come to rest, these fragments served as a new substrate for new generations of the microorganisms. These micro-organisms thus survived by continued growth on the reworked fragments and built up new stromatolites that may show an ‘angular disconformity＇ with the stromatotites of their substrate. It thus is shown that stromatotites have an adequate response to a sudden disturbance of their habitat, and that they survive earthquakes by colonization of broken-off fragments. We call the ‘healed＇ fragments ‘tombotiths＇（tumbled stones）.

关键词： Stromatolites Seismic shocks Soft-sediment deformation structures Pataeoproterozoic Singhbhum craton Tombotiths India

Seismites resulting from high-frequency, high-magnitude earthquakes in Latvia caused by Late Glacial glacio-isostatic uplift

在线全文

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2016年第4期5卷 363-380页

作者： A.J. (Tom) van Loon Matgorzata Pisarska-Jamrozy Maris Nartiss Maris Krievans Juris Soms geocom Consultants Valle del Portet 17 03726 Benitachell Spain Institute of Geology Adam Mickiewicz University Makow Polnych 16 61-606 Poznan Poland Faculty of Geography and Earth Sciences University of Latvia Rainis Blvd. 19 1576 Riga Latvia Department of Geography Daugavpils University Parades 1 LV 5401 Daugavpils Latvia

Geologically extremely rapid changes in attitude by glacial rebound of the Earth crust after retreat of the Scandinavian Ice Sheet at the end of the last Weichsetian glaciation influenced the patae- ogeography of northern Europe. The up（ift of the Earth crust apparently was not gradual, but shock-wise, as the uplift was accompanied by frequent, high-magnitude earthquakes. This can be deduced from strongly deformed layers which are interpreted as seismites. Such seismites have been described from several coun- tries around the Baltic Sea, including Sweden, Germany and Poland. Now similarly deformed layers that must also be interpreted as seismites, have been discovered also in Latvia, a Baltic country that was covered by an ice sheet during the last glaciation. The seismites were found at two sites： Near Vatmiera in the NE part and near Rakuti in the SE part of the country. The seismites were found in sections of about 7 m and 4.5 m high, respectively, that consist mainly of glaciofluvial and gtaciotacustrine sands and silts. At the Vatmiera site, 7 seismites were found, and at the Rakuti site these were even 12 seismites. The two sections have not been dated precisely up tilt now, but lithological correlations and geomorpho- logical characteristics suggest that the sediments at the Vatmiera site cannot be older than 14.5 ka. Because the accumulation of the section did not take more than about 1000 years, the average recurrence time of the high-magnitude （M≥4.5-5.0） earthquakes must have been maximally only 100-150 years, possibly only 6-7 years. The sediments at Rakuti must also have formed within approx. 1000 years （17-16 ka）, implying a recurrence time of high-magnitude earthquakes of maximaUy once per 100-200 years.

关键词： Soft-sediment deformation structures (SSDS) Seismites Latvia Glacio-isostatic rebound,Earthquake recurrence time

在线全文

学校读者我要写书评

暂无评论

工程地质计算机应用网站BBS论坛说明

工程地质计算机应用 2000年第2期 2-2页

作者：任鸣春 geocom 网络管理

为使大家更好地利用好工程地质BBS论坛这块讨论阵地,探讨问题,交流经验,现将任大师在网上发布的关于BBS论坛的使用说明全文刊出,供朋友们应用参照

关键词： BBS 上传文件工程地质计算机应用网站