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1.
During the last year I had ample opportunity for geologicalexcursions in the surroundings of Nanking,both with the students of theDepartment of Geology of National Central University,and in connectionwith fieldwork for the Geological Research Institute of the AcademiaSinica.From casual observations on these trips,I came to some  相似文献   

2.
王竹泉 《地质学报》1936,15(1):87-104
INTRODUCTION The maganese deposit of Hsihutsun was first visited by Dr.V.K.Ting~1 in 1922.During the spring of 1932 while directing students of the Geolo-gical Department of the Peking University in the field,the writer had an op-portunity to study the deposit.A detailed geologic map has been prepared,but  相似文献   

3.
郑厚怀  袁见齐 《地质学报》1936,15(3):361-379
Towards the end of last November,the writers accompanied by aparty of several students took trip to Huantzetung (貛子洞) as one ofthe field excursions forming a part of an elementary course on econo-mic geology offered at the Department of Geology,National Central  相似文献   

4.
《地质学报》1937,17(1)
Early in April 1935 the senior writer together with his formercolleague,Prof.T.O.Chu took a party of students of the graduatingclass of the Department of Geology,National Central University to theiron and copper mining region of south-eastern Hupeh.One of thelocalities visited is the celebrated iron deposit of Tayeh now in active  相似文献   

5.
章鴻釗 《地质学报》1922,1(Z1):27-31
This was not only a regular meeting,but also a gathering to welcomethe Japanese palaeontologist,Dr.I.Hayasaka,who recently came to study thegeology of northern China with his students of the Tohoku Imperial Univer-  相似文献   

6.
This was not only a regular meeting,but also a gathering to welcomethe Japanese palaeontologist,Dr.I.Hayasaka,who recently came to study thegeology of northern China with his students of the Tohoku Imperial Univer-  相似文献   

7.
In the years 2000 and 2001 a few visionaries in IUGS under the lead of Ed de Mulder, at that time President of IUGS, started to think out loudly about an "International Year of Planet Earth" (YEAR). It was their feeling that globally the geosciences did not get that part of public recognition that geosciences should earn, compared to ecology, economy, sustainable development and environmental sciences at large. They were convinced that geosciences could contribute much more to the well-being of the human society if the available knowledge of geoscientists would be used wisely. The low awareness of the benefits of geosciences to society in the public and at the level of politicians and decision-makers, created a long-lasting and continuing decrease of financial means which was and still is crucial for the decrease in the absolute number of geoscience projects, the reduction of respective university institutes, the closing of federal or state geological surveys or merging them with other institutions, and by such reducing the possibility of immediate impact and action, and, last, but not least, in a decreasing number of university students in geosciences. From the beginning of the considerations it was evident that the YEAR must combine science and outreach components in a balanced way. The best way to reach this challenge seemed to target an "International Year of Planet Earth", proclaimed by the United Nations.  相似文献   

8.
Impact cratering is one of the fundamental processes in the formation of the Earth and our planetary system, as reflected, for example in the surfaces of Mars and the Moon. The Earth has been covered by a comparable number of impact scars, but due to active geological processes, weathering, sea floor spreading etc, the number of preserved and recognized impact craters on the Earth are limited. The study of impact structures is consequently of great importance in our understanding of the formation of the Earth and the planets, and one way we directly, on the Earth, can study planetary geology.
The Nordic-Baltic area have about thirty confirmed impact structures which makes it one of the most densely crater-populated terrains on Earth. The high density of identified craters is due to the level of research activity, coupled with a deterministic view of what we look for. In spite of these results, many Nordic structures are poorly understood due to the lack of 3D-geophysical interpretations, isotopeor other dating efforts and better knowledge of the amount of erosion and subsequent tectonic modifications.
The Nordic and Baltic impact community is closely collaborating in several impact-related projects and the many researchers （about forty） and PhD students （some seventeen） promise that this level will continue for many more years. The main topics of research include geological, geophysical and geochemical studies in combination with modeling and impact experiments. Moreover, the Nordic and Baltic crust contains some hundred suspect structures which call for detailed analysis to define their origin.
New advanced methods of analyzing geophysical information in combination with detailed geochemical analyses and numerical modeling will be the future basic occupation of the impact scientists of the region. The unique Cretaceous/Tertiary boundary （K-T） occurrences in Denmark form an important source of information in explaining one of the major mass extinctions on Earth.  相似文献   

9.
《《幕》》2008,31(3):354-354
The American Association of Stratigraphic Palynologists （AASP） held its 40th annual meeting this year in Panama City, Panama from 9-12 September. Meeting organizer and AASP president Carlos Jaramillo （Smithsonian Tropical Research Institute, Panama） received 50 abstracts from 18 coun- tries. There were 68 attendees, a quarter of them students. This year＇s meeting was spon- sored by： AASP, ExxonMobil,  相似文献   

10.
《四川地质学报》2009,(Z1):124-132
Based on the theory of ecological footprint,the article established the component models of the ecological footprint,including the dinner,the accommodation,the shopping,the transportation,the sightseeing and the entertainment,to make a research on the tourism ecological footprint of XiaoYanwan scenic areas.Through the research,we have found out the transportation ecological footprint accounted for the largest proportion of the total tourism ecological footprint which is 5739.81 hm 2,the dinner ecological footprint is second only to it,the shopping ecological footprint and the entertainment ecological footprint is considered negligible.The ecological deficit of the whole scenic areas is 4020.13 hm 2.Only if the ecological resources are exploited reasonbly,is the sustainable development of the tourism guaranteed.  相似文献   

11.
The Philippine Sea Plate is located at the convergence zone of the Eurasian Plate,the Pacific Plate,and the Indo-Australian Plate.This paper divides the Philippine Sea Plate into two second-order tectonic units and eight third-order tectonic units by summarizing the marine geological,geophysical,and submarine geomorphological data of the Philippine Sea Plate collected for years and referring to the seafloor spreading theory and the trench-arc-basin system.The two second-order tectonic units are the West Philippine Sea block and the Izu-Bonin-Mariana arc-basin system.The former includes the West Philippine Basin,the Huatung Basin,the Daito Basin,and the Palau Basin,while the latter consists of the Kyushu-Palau Ridge,the Shikoku-Parece Vela Basin,the Izu-Bonin Arc,and the Mariana Arc.Furthermore,this study concludes that the Philippine Sea Plate has undergone three stages of tectonic evolution,namely the early stage of the evolution of marginal basins with Cretaceous basement(Early Cretaceous),the middle stage of the spreading of the West Philippine Basin(Eocene),and the late stage of the subduction of the Izu-Bonin-Mariana arc-basin system(Oligocene-present).The Kyushu-Palau Ridge is a window to discover the tectonic evolution of the Philippine Sea Plate due to its unique geographical location.  相似文献   

12.
V. Ye. Glotov 《冰川冻土》2004,26(Z1):286-290
In selecting methods of liquidation of natural pollution resulted from oil products (OP) in the cold regions, such as in the north coast of the Sea of Okhotsk, it is necessary to take into consideration the peculiarities of the OP and the object polluted in cold and warm periods. Generally, in cold time snow cover with thickness of 1. 0m or more presents, so the OP is partly absorbed by the silt in the snow, then the viscosity of snow is strengthened due to the aggregate of the hard hydrocarbon components (HCC) with negative temperature in the OP. The HCC is the most active when the molecular of carbon atom is less than 10, and could not be harden at the temperature below -30 ℃. However, in summer time the spilled HCC is partly evaporated, but the tar and asphalt enrich the OP there. In the mountainous regions at the deep deposition of underground water, in summer the OP might be brought by the gas stream in the massifs of the fracture rocks upper on the slope. According to the peculiarities, the methods of fighting the nature, polluted by the OP in the regions of the Sub-Arctic; are explained, and they are representative in the north coast of the Sea of Okhotsk.  相似文献   

13.
Lying at the junction of the Dabashan, Longmenshan and Qinling mountains, the Micangshan Orogenic Belt coupled with a basin is a duplex structure and back-thrust triangular belt with little horizontal displacement, small thrust faults and continuous sedimentary cover. On the basis of 3D seismic data, and through sedimentary and structural research, the Micangshan foreland can be divided into five subbelts, which from north to south are: basement thrust, frontal thrust, foreland depression-back-thrust triangle, foreland fold belt or anticline belt, and the Tongjiang Depression. Along the direction of strike from west to east, the arcuate structural belt of Micangshan can be divided into west, middle and east segments. During the collision between the Qinling and Yangtze plates, the Micangshan Orogenic Belt was subjected to the interaction of three rigid terranes: Bikou, Foping, and Fenghuangshan (a.k.a. Ziyang) terranes. The collision processes of rigid terranes controlled the structural development of the Micangshan foreland, which are: (a) the former collision between the Micangshan-Hannan and Bikou terranes forming the earlier rudiments of the structure; and (b) the later collision forming the main body of the structural belt. The formation processes of the Micangshan Orogenic Belt can be divided into four stages: (1) in the early stage of the Indosinian movement, the Micangshan-Hannan Rigid Terrane was jointed to the Qinling Plate by the clockwise subduction of the Yangtze Plate toward the Qinling Plate; (2) since the late Triassic, the earlier rudiments of the Tongnanba and Jiulongshan anticlines and corresponding syncline were formed by compression from different directions of the Bikou, Foping and Micangshan-Hannan terranes; (3) in the early stage of the Himalayan movement, the Micangshan-Hannan Terrane formed the Micangshan Nappe torwards the foreland basin and the compression stresses were mainly concentrated along both its flanks, whereas the Micangshan-Hannan Terrane wedged into the Qinling Orogenic Belt with force; (4) in the late stage of the Himalayan movement, the main collision of the Qinling Plate made the old basement rocks of the terrane uplift quickly, to form the Micangshan Orogenic Belt. The Micangshan foreland arcuate structure was formed due to the non-homogeneity of terrane movement.  相似文献   

14.
This paper aims to study the influence of the number and distribution of drill samples on the simulation accuracy of the lithology field. This research mainly applies the variation function method in geo-statistics, and determines important indicators such as the variation, and then the lithology field is simulated by sequence index simulation. It is shown that(1) simulation error decreases with the increase of sampling density;(2) at the scale and complexity of this study, when the sampling density reaches 40/km^2, the average error of the lithology field simulation can be less than 2.0%;(3) in the study mode of examples, the simulation results of random sampling in the whole region are the most ideal, with an average error of 5.4%. The average error of the simulation results of the centralized sampling is about 10 times that of the random sampling method;(4) known from the influence analysis of the degree of study sample unevenness influence on the imitation results, under the same sample size, the simulation error decreases with the increase of the most adjacent index. When the nearest index reaches 1, the simulation error will be less than 6%, and the error variable range is within 3%.  相似文献   

15.
青藏铁路冻土路基沉降变形现场试验研究   总被引：3，自引：0，他引：3  
Based on the field data of ground temperature and roadway settlement observed during the construction of the experimental embankments over permafrost along the Qinghai-Tibetan Railway, this paper discusses the differences of frost process on the roadway surface from that on the natural ground surface, the changes of permafrost table under the roadway embankment, and the peculiarities of roadway settlement. Analyses of the test results show : 1) The differences of the freezing indexes between the roadway surfaces and the natural ground surfaces are less than those of the thawing indexes for all the test sections; 2) Since the measures of permafrost protection were taken, the permafrost tables under the embankments have raised after the roadway was constructed. The minimum is about 0.4 m and the maximum is 1.2 m; 3) the settlements of the roadway are mainly from the compression and creep of the icerich frozen soils under the original permafrost tables and the maximum has reached 6 ～ 8 cm during the first year after the embankments were constructed. Moreover, concerning the processes of roadway settlement, the deformation of the embankments has no obvious trend of attenuation at present. Especially,for the roadway with high embankments, the settlement may reach a remarkable value and much consideration must be given for this problem.  相似文献   

16.
The Shangzhuang altered-rock type gold ore deposit is located in the middle segment of and controlled by the Wang＇ershan fault zone in the northwestern part of the Jiaodong gold province, China. The deformation evolution, the structure of strain and stress fields and its ore-controlling effect in the Shangzhuang deposit are discussed in this paper. It is revealed that the deformation evolution has mainly undergone four phases： the early ductile deformation, the second NE-striking horizontal simple shear, the third NE-striking compression-shear and the final NW-striking compression. The mineralization happened during the third stage in which the maximum principal stress gradually transited from NE to NW. The 3-D numerical simulations of the stress field show that, on the condition that the maximum principal stress is NE-striking, the fracture development in the fault zone is favored, while when the maximum principal stress is NW-striking, the fault zone is relatively extensional and it is suitable for the influx and emplacement of ore-forming fluids. The compression-shear strain field during the mineralization is characterized by the λ-type structure, the positive flower structure, etc. Orebodies are mostly equidistantly located in the dilatational spaces, which are distributed in the integral compressional circumstances. And the dilatational spaces are developed where the fault attitude changes or shear joint systems develop. In the overall compression-shear stress field, the strain field bears self-similarity at multiple scales, including the orebody, ore deposit and orefield. The selfsimilarity of the structure comprises the subequidistant distribution of fractures at the same scale and the similar shape of the fractures at various scales. Yet, due to the special geological structure, the orebodies are mostly located in the hanging wall in the Shangzhuang deposit, which is different from most deposits in the Jiaodong gold province. Analyses of the ore-controlling stress and strain fields in the deposit pro  相似文献   

17.
The Yalong River is an important river that runs across the abruptly changing terrain of the SE Tibetan Plateau. The terraces and Quaternary sediments in its valleys preserve the information of tectonic uplift,climate changes,and landform evolution since the Middle Pleistocene. Based on geomorphological,sedimentological,and chronological investigations,6–8 terraces are identified in the lower reaches of Yalong catchment and its tributary—the Anning River. The electron spin resonance(ESR) or optically stimulated luminescence(OSL) data on the alluvial sediments in the upper portion of terraces indicate that they formed in 1.10,0.90,0.72,0.06–0.04,0.03–0.02,and 0.01 Ma. Tectonic uplift and the climatic cycle controlled the formation of the Yalong River terraces. The former dominated the dissection depths and incision rates,whereas the latter controlled the transformation between accumulation,which developed during the glacial period,and incision,which developed during the glacial-interglacial transition. The Yalong downstream incised rapidly from 1.10 to 0.72 Ma and rapidly from 0.06 Ma until the present; the terraces developed during these two periods. The incision rates in space during the two periods indicate the uplifting extent of the Jinpingshan area,which decreases toward the east and the south. The results reveal two rapidly uplifting stages in the SE Tibetan Plateau,including an accelerated uplifting since 0.06 Ma. Since the Middle Pleistocene,the tectonic uplift of the SE and NE parts of the Tibetan Plateau is synchronous,according to the same development stages of the river terraces of the Yalong downstream and the Yellow River in the Lanzhou area of the NE Tibetan Plateau. The difference in the horizontal displacement between the Xianshuihe Fault and the Anninghe Fault bend resulted in the rapid uplift of the Jinpingshan area. The incision rate for the spatial distribution of the Yalong downstream is the geomorphological response of crustal shortening and uplift differences in the SE margin block of the Tibetan Plateau. The southeastward diffusion process of the Tibetan Plateau was recorded.  相似文献   

18.
There are numerous controversies surrounding the tectonic properties and evolution of the Proto-South China Sea(PSCS).By combining data from previously published works with our geological and paleontological observations of the South China Sea(SCS),we propose that the PSCS should be analyzed within two separate contexts:its paleogeographic location and the history of its oceanic crust.With respect to its paleogeographic location,the tectonic properties of the PSCS vary widely from the Triassic to the mid-Late Cretaceous.In the Triassic,the Paleo-Tethys and the Paleo-Pacific Oceans were the major causes of tectonic changes in the SCS,while the PCSC may have been a remnant sea residing upon Tethys or Paleo-Pacific oceanic crust.In the Jurassic,the Meso-Tethys and the Paleo-Pacific oceans joined,creating a PSCS back-arc basin consisting of Meso-Tethys and/or Paleo-Pacific oceanic crust.From the Early Cretaceous to the midLate Cretaceous,the Paleo-Pacific Ocean was the main tectonic body affecting the SCS;the PSCS may have been a marginal sea or a back-arc basin with Paleo-Pacific oceanic crust.With respect to its oceanic crust,due to the subduction and retreat of the Paleo-Pacific plate in Southeast Asia at the end of the Late Cretaceous,the SCS probably produced new oceanic crust,which allowed the PSCS to formally emerge.At this time,the PSCS was most likely a combination of a new marginal sea and a remnant sea;its oceanic crust,which eventually subducted and became extinct,consisted of both new oceanic crust and remnant oceanic crust from the Paleo-Pacific Ocean.In the present day,the remnant PSCS oceanic crust is located in the southwestern Nansha Trough.  相似文献   

19.
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20.
On the 31 of August,1932,the writer of the present paper was ap-pointed one of the five members by the National Geological Survey,Peking tosurvey the soils of the Weiho plain in Central Shensi.For the most part ofthe trip the writer had the pleasure to ac  相似文献   

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