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Episodes 2007年第4期30卷 258-270页

作者： Daniel Goldman Stephen A. Leslie Jaak Nōlvak Seth Young Stig M. Bergstroem Warren D. Huff Department of geology University of Dayton 300 College Park Dayton Ohio 45469 USA deparment of geology and Environmental Science James Madison University MSC 6903 Harrisonburg VA 22807 USA Institute of geology at Tallinn University of Technology Ehitajate tee 5 19086 Tallinn Estonia School of Earth Sciences Division of Geological Sciences The Ohio State University 155 S. Oval Mall Columbus Ohio 43210 USA Department of geology University of Cincinnati Cincinnati Ohio 45221 USA.

The Global Boundary Stratotype Section and Point （GSSP） for the Katian Stage of the Upper Ordovician Series is defined as the 4.0 m-level above the base of the Bigfork Chert in the Black Knob Ridge section, southeastern Oklahoma. This point in this section is coincident with the first appearance of the graptolite Diplacanthograptus caudatus, which has proved to be a reliable datum for precise worldwide correlation. The FAD ofD. caudatus occurs very near the first occurrences of the graptolites D. lanceolatus, *** americanus, Orthograptus pageanus, O. quadrimucronatus, Dicranograptus hians, and Neurograptus margaritatus. This rapid succession of fossil species appearance events provides a secure basis for identification of the base of the Katian Stage of the Upper Ordovician Series and for its global chronostratigraphic correlation.

关键词：层形断面奥陶纪俄克拉荷马州美国地质特点

多层褶皱的协调分析分类——以印度中部变质岩群为例

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地质科学译丛 1997年第4期14卷 6-8,12页

作者： Vaibhava Srivastava 田晓阳 deparment of geology Banaras Hindu UniversityVaranasi 221005India

比较单个褶皱不同层面的 b_3/b_1(傅里叶级数协调分量的第三个系数和第一个系数之比),能客观地确定多层褶皱的协调性。b_3/b_(1-n)图(n 为褶皱层面数)是估计褶皱协调性的一种简单图示方法。图中平行横坐标的直线指严格协调褶皱,而其它... 详细信息

比较单个褶皱不同层面的 b_3/b_1(傅里叶级数协调分量的第三个系数和第一个系数之比),能客观地确定多层褶皱的协调性。b_3/b_(1-n)图(n 为褶皱层面数)是估计褶皱协调性的一种简单图示方法。图中平行横坐标的直线指严格协调褶皱,而其它直线和曲线则指层面与层面形态不同的各种褶皱。根据不协调指数(INH)本文提出一种新的多层褶皱分类。不协调指数能反映褶皱层面形态变化的度。从1/4波长段内层面数 n 的 b_3/b_1 的标准偏差(σ_n)可求得 INH,根据 INH(=1000σ_n)的值,多层褶皱可分为:严格协调(INH=0),近协调(075)。对印度中部经多次变形的前寒武岩石进行实例研究,发现褶皱时代越晚(越新),其不协调指数越小。

关键词：多层褶皱协调性分析不协调指数变质岩群

A Proposed Geoheritage Inventory System: Case Study of Isalo National Park, Madagascar

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Journal of Geoscience and Environment Protection 2016年第5期4卷 163-172页

作者： Hasina N. Randrianaly Andrea Di Cencio Aroniaina Rajaonarivo Tsilavo Raharimahefa Département de Paléontologie et d’Anthropologie Biologique Faculté des Sciences Université d’Antananarivo Antananarivo Madagascar geology & Paleontology Technical Studio San Casciano Val di Pesa (FI) Italy Isalo National Parks Ihorombe Madagascar deparment of geology University of Regina Regina Canada

Geological heritage inventory procedures and templates have been principally emerged from European countries. Each of these countries has developed its proper method of inventory based on its natural heritage, recognized on local and/or regional scales. Natural sites were mainly identified and characterized in a particular geological context, which is usually very unique, valuable and impressive;resulting in the protection of the sites. Madagascar is known internationally as a beautifully landscaped island, but the impressive sites were not cataloged. We carried out a series of field inventory of potential geological sites within the Isalo National Park in southern Madagascar. We invented several inventory sheets in order to record the most detailed information about the sites identified within the park. This is to aid in organizing the park and to establish a sustainable base for the creation of a geopark, and also they help us to build a database for geosites and their classifications. This article suggests a prototype model for inventorying intangible geosites, paleosites and geomorphosites. Our inventory sheets help to identify and to promote geological importance of any sites, not only for academia but also for other sectors such as tourism and conservation.

关键词： Inventory Sheets Geoheritage Geosites Paleosites Geomorphosites Park National Isalo Park Madagascar

Use of Soil Physicochemical Properties in Assessment of Soil Erosion: A Case Study of Agbor, South-South Nigeria

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Research in Ecology 2021年第1期3卷 41-51页

作者： Ruth Oghenerukevwe Eyankware Ulakpa Wisdom Chukwuemeke Ulakpa Moses Oghenenyoreme Eyankware Department of Environmental Management and Pollution Control Nigeria Maritime UniversityOkerenkokoNigeria Department of Chemical Engineering Federal University of TechnologyMinnaNigeria deparment of geology Ebonyi State UniversityEbonyi StateNigeria Geomoses Consultancy Limited Warri Delta StateNigeria

The study area is one of the areas in the South-South region of Nigeria that has been ravaged by *** has led to loss of infrastructures and impact on the livelihood of the inhabitants of the study *** this study,the physio-chemical of soil in Agbor and its neighboring communities were assessed in eleven different locations.A total of eleven soil samples,consisting of 5 samples each at a depth of 0–200 cm were taken in accordance with the clarification of different *** samples were air-dried,crushed and sieved in 2mm mesh sieve then subjected to analysis for both physical and chemical properties in the *** physiochemical analysis results showed that pH value ranges from 5.0 to 6.3 indicating very strongly acidic to strongly *** density ranged from 1.29 to1.35 indicating a slight increase due to the presence of sand *** low level of porosity which ranged from 49.4 to *** low level obtained from Total Organic Matter(TOM)indicates intense rainfall and constant *** low Ca,Mg,K+and Na+values indicate intense rainfall and leaching *** values obtained from Al3+,H+,EA and P revealed a slight increase and cause of acidity nature across eleven soil test *** properties showed by all soils revealed that they are vulnerable to weathering,leaching,easy removal by runoff and low resistivity.

关键词： Soil Depth Rainfall Erosion Agbor and Nigeria

Geotechnical Perspective of the Causes of Cracks in Building of University Campus(Sindh University Jamshoro Sindh Pakistan)

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Journal of Building Material Science 2021年第1期3卷 51-57页

作者： Mushtaque Amed Pathan Maryam Maira Arif Khaskheli Agha Jamshed Center for Pure&Applied geology University of SindhJamshoroPakistan Institute of Environmental Engineering&management Mehran UniversityJamshoroPakistan Material Engineer Prof.Dr.G.B Khaskheli Civil Engineering Lab.JamshoroPakistan deparment of Architecture Engineering Mehran UniversityJamshoroPakistan

The building construction throughout world faces the defects from normal to heavy and destructive like cracks and fractures which cause damages and eventually collapses to heavy life losses alongside economical and *** cracks like structures are found in wall and columns *** the aim of the study,the international experts have classified the minimum allowable standards of those defects which can not be harmful to buildings and other people living *** research study has been administered to research the most reasons to research the causes of cracks during a newly completed and used buildings in where some distinct cracks appeared immediately and after some *** these cracks seem in almost in walls,columns,beams,and so-like structures having different *** foremost useful and customary methods consisting of reconnaissance survey;building inspection and laboratory testing were wont to investigate the causes of those distinct cracks which will cause the formation of cracks were considered and analyzed by the utilization of reconnaissance survey,factors like width,pattern,and conditions of the cracks were identified during the building inspection stage and therefore the soil properties associated with the creation of cracks were determined during the laboratory *** the results of the study;there was no distinct evidence of things like a matured system which will cause the creation of cracks within the building;The pore water pressure during this sort of soil takes longer time to fade,which may be expressed by the very low value of the coefficient of permeability(1.90x 10-7 to 2.15 x 10-7 m/s)acquired from different soil samples collected from the study *** the cracks during this sort of building were found to be caused by the settlement of the building thanks to the character of the predominant soil type that was found within the study area,all the cracks are active cracks with their width increasing with time and the

关键词： Buildings Cracks Plasticity indices Coefficient of permeability Pore water pressure Moisture content Differential settlement