IN CELEBRATION OF THE 30TH ANNIVERSARY OF THE ESTABLISHMENT OF XI''''AN INSTITUTE OF GEOLOGY AND MINERAL RESOURCES

In order to strengthen geological researches and to concentrate superiorforces on solving major and important problems in key geological researchprojects, the Ministry of Geology decied to amalgamate the institutes ofShaanxi, Gansu, Ningxia, Qinghai and Xinjiang Provinces (AutonomousRegions), and in October, 1962 the Northwest Institute of Geological Sciences,affiliated then to the Ministry of Geology, was officially established     

CHARACTERIZATION AND FORMATION MECHANISM OF THE CENTRAL UPLIFT OF THE QIANGTANG BASIN

The Qiangtang basin is located between Kekexili-Jingshajiang suture belt and Bangong-Lujiang suture belt, and is divided into the north part and south part by the central uplift that has no crop out of Mesozoic strata. When the Jinshajiang Ocean was closed, the subducting plate was subducted southward. In the central part of the Qiangtang basin, the cushioning effect of the asthenosphere resulted in the thermal doming of the mantle and subsequent large-scale anatexis. Mantle source materials and antectic materials were upwelled and extruded into the middle crust, leading to the thickening of the middle crust and the heating and weakening of the middle to upper crust, and resulting in the rapid deformation (detachment) and tectonic erosion, and in the isostatic uplifting and the formation of metamorphic core complex. The upwelling of anatectic materials would further enhance the buoyant repercussion, which would combine with the side stress due from extrusion in resulting in the formation of an extension     

FOST PALEOZOIC FORMATIONS OF THE MN YIN AND LAI WU VALLEYS OF SHANTUNG.

INTRODUCTION. I was appointed to accompany Dr. J. G. Andersson to take a trip incentral Shantung. especially in Men Yin (蒙阴) and Lai Wu (莱芜),valleys,for the purpose of collecting fossils and observing the post-Palaeozoic forma-tions. We came back to Peking in December, 1922. The conclusion     

FORMAT OF REFERENCES CITED

The Geotectonica et Metallogenia adopts a reference citation system in the form of author(s) plus publication year in the text, i.e., author (year) for single author, author 1 and author 2 (year) for two authors, or author 1 et al. (year) for authors of three and above. Here all authors generally refer only to their last names or family names no matter their nationalities. In regard to the list of references following the text, the format shall comply with the following general stipulations:     

LITHOFACIES PALEOGEOGRAPHY OF EARLY PALEOZOIC OF NORTH CHINA PLATFORM

Ⅰ.INTRODUCTIONNorth China platform extends beyond Yinshan Mountains in the north,beyond HelanMountains in the west,to Qilian Mountains,Qinling Mountains,Funiu Mountains and DabieMountains in the south,and to the sea in the east.It covers the whole or part of Gansuprovince,Shannxi province,Ningxia Autonomous Region,Inner Mongolia Autonomous Re-gion,Shanxi province,Hebei province,Shandong province,Liaoning province,Jilin prov-ince,Jiangsu province,Anhui province,Henan province,Beijing Municipality,Tianjin MunieiPality, Bohai sea and Huanghai sea.     

APPLICATION OF SOME MECHANICAL CONCEPTS TO STRUCTURAL GEOLOGY

This paper discusses some mechanical concepts that have been largely applied to structural geology and tectonics, and addresses the problems and misunderstandings in use of these mechanical terms. The purpose is to stimulate the interests for structural geologists in using the mechanical principles and methods correctly to solve the geodynamic problems.     

ON A MESOLITHIC(■)INDUSTRY OF THE CAVES OF KWANGSI

INTRODUCTION In the beginning of 1935,a party of geologists was sent by Di.W.H.Wong,Director of the Geological Survey,in order to survey the Cenozoicformations of Kwangsi.The party,including P.Teilhard de Chardin,Dr.C.C.Young and the author,was met in Canton and greatly assisted in thefield by Dr.H.C.Chang,Professor at the Sunyatsen University (Canton).     

SEDIMENTARY PATTERN OF PROTOTYPE BASIN IN THE DEPOSITION PERIOD OF LAIYANG FORMATION AND THE ADVANTAGEOUS AREAS FOR OIL AND GAS EXPLORATION OF JIAOLAI BASIN

1 Introduction As a Mesozoic relict terrestrial basin controlled and reformed by fracture activities in themiddle to late stage in Mesozoic, Jiaolai basin is situated in the middle of the Ludong uplift, beingoverthrusted upon Jiaobei uplift in the north, adjoining Jiaonan uplift in the south atWulian-Rongcheng fracture, being connected to Tanlu fracture belt in the west, with its NE partextending into the Yellow Sea and connecting to Qianliyan uplift at Qianliyan fracture. Due totec…     

DETACHMENT FAULT IN DINGGYE AREA IN THE MIDDLE PART OF THE HIMALAYAN OROGEN

Dinggye lies in the middle part of the Himalayan Orogen. A lot of low angle extension detachment faults have been developed in Dinggye area and some of them make up the main body of the South Tibet Detachment System. On the whole, the extension direction of all the detachment faults is perpendicular to the strike of the Himalayan Orogen. Each detachment fault has its distinct characteristics. Mylonite was extensively developed in the detachment faults and can be divided into a variety of types such as siliceous mylonite, felsic mylonite, granite mylonite, protomylonite, crystallization mylonite and so on. On the basis of our field survey works, these detachment faults can be classified according to their locations into three units listed as follows: (1) In the northern part of the study area, the detachment faults occur on large scale and in orbicular shape, and form the middle layer of the metamorphic core complexes. (2) In the southern part of the study area, the detachment faults occur in linear shape that is parallel to the Himalayan Orogen and has a stable attitude, and have undergone two phases of development. In the first phase, the Rouqiechun Group rocks were formed and make up the hanging wall, while in the second phase the Jiachun Group rocks were formed and make up the hanging wall. (3) In the southeastern part of the study area, the detachment faults strike nearly along southeast direction in a stable way and some of these detachment faults were distorted by the late-formed faults and folds. Furthermore, in the southwestern part of the study area, the ductile shear zones are parallel to the detachment faults.     

CHARACTERISTICS OF AROMATIC HYDROCARBONS IN CRUDE OILS

Crude oils from different basins in China ,Australia and New Zealand were analyzed to character-ize aromatic hydrocarbons produced in different environments by means of GC/MS .The distributions of some common compounds such as naphthalene, phenanthrene, chrysene,pyrene, fluoranthene, fluorine,dibenzothiophene and dibenzofuran were found to be related to sedimentary environments.Especially the relative contents of fluorenes ,dibenzofurans and dibenzothiophenes can be used to di-vide the oils into three types(1) saline or marine carbonate environment;(2) fresh-brackish water lake;(3) swamp and coal-bearing sequence.A romatic biomarkers (e.g.retene, nor-abietene,derivatives of lupeol and β-amyrin)represent higher plant inpults with respect to the precursors of crude oils. High contents of sulphur-containing compounds like benzothiophene and dibenzothiophene series indicate a reducing sulphur-abundant diagenetic condition .The benzohopane series (C32-C35) was identified both in hypersaline and coal-bearing basins, and it is postulated to be the result of strong bacteria activity.In all the sam-ples, a complete series of alkyl benzenes was analyzed .The similarity of its carbon-number distrbu-tion with that of n-alkanes probably suggests their genetic relationship. The distribution of the methylphenanthrene series reflects the evolution degree of crude oils,MPI holding a positive correlation with C29-sterane 20S/(20S 20R).     

RESPONSE OF TRIASSIC SEQUENCE STRATIGRAPHY OF LOWER YANGTZE TO THE COLLISION BETWEEN THE YANGTZE PLATE AND THE NORTH CHINA PLATE

The characteristics of the Triassic sequences developed in the Lower Yangtze area display some great changes in both environment and climate. The change of environment was a transition from marine to continent via alternating environments. The change of climate was a transition from tropic （torrid） to warm and wet climate via subtropic dry climate. The type variations of the sequences were from the marine sequences to the continental sequences, corresponding to the changes of environments and climates. Sequence 1 is a type II of sequence of mixed elastic and carbonate sediments; sequence 2 is a type I of sequence of carbonate platform; sequence 3 is a type I of sequence of carbonate tidal flat-salt lagoon, sequence 4 is a type iI of sequence of lacustrine within marine layers, and sequence 5 is a sequence of lacustrine-swamp. The development, distribution and preservation of those sequences reveal the tectonic controls and their changes in the background. The collision between the Yangtze plate and the North China plate was a great geological event in the geological history, but the timing of the collision is still disputed. However, the characteristics of Triassic sequence stratigraphy and sea level changes in the Lower Yangtze area responded to this collision. The collision started at the beginning of middle Triassic and the great regression in the Lower Yangtze area started 22Ma earlier than those in the world. The tectonic conditions occurred before and during the collision controlled the development of sequences and type changes.     

APPLICATION OF THE DC RESISTIVITY METHODS TO THE STUDY OF GROUNWATER IN THE WESTERN PART OF AMMAN BASIN, JORDAN

1. Introduction In many parts of the world, the technique of electrical sounding has been used effectively for solving subsurface water problems in order to minimize drilling costs (e.g. Breusse 1963; Zohdy and Jackson, 1969; Zohdy, 1969; Zohdy et. al. 1984). During June 1999, resistivity surveys was made at the western Amman basin to provide some information about the thickness, lithology and tectonics of the subsurface layers and then to locate suitable drilling sites for water wells. T…     

STRUCTURAL CHARACTERISTICS OF THE NIUSHOU MOUNTAIN AND ITS GEOLOGICAL SIGNIFICANCE IN CENTRAL NINGXIA

There are many thrust-related structures occurring in the Paleozoic strata of the Niushou Mountain in the central part of Ningxia Hui Autonomous Region. The fault-related folds are the typical structures in this area. Based on the analysis about these structures and their relationships, the processes by which these structures of the Miboshan Formation were formed are reconstructed, and the strata underwent about three stages of deformation: (1) horizontal shortening, (2) folding, and (3) thrusting. And the fact that the Niushou Mountain is the leading edge of an old thrust sheet was proved, the Niushou Mountain, the Daluo Mountain and the Xiaoluo Mountain together constitute the front part of this old thrust zone, so the Niushou Mountain and the Ordovician strata in the central and southern parts of Ningxia now are likely allochthons. In the period from middle Ordovician to Devonian, the areas of the central and southern Ningxia belonged to the back-arc foreland basin of North Qilianshan orogen, which was adjacent to the continent in the north. In the later part of the early Paleozoic period, the Niushou Mountain was formed after the closure of the back-arc foreland basin.     

HEFEI BASIN IN EARLY CRETACEOUS -CHARACTERIZATION AND ANALYSIS OF PETROLEUM POTENTIAL

Comprehensive analyses were made based on seismic prospecting data, electrical prospecting data and basin simulation data as well as regional geological data and thorough discussions were conducted about the complicated structures, features and evolution of Hefei Basin in Early Cretaceous in this study, and it was derived that that Hefei Basin was a composite basin formed during the transformation of the stress field from compressive toward tensile in Early Cretaceous. In other words, this basin was a foreland basin of gliding-thrust type, which is mainly controlled by the Dabie orogenic belt in the south side in the early to middle period of Early Cretaceous, while being a strike-slip basin of pull-apart type, which is mainly controlled by the activity of Tanlu fracture in the east side in the middle to late period of Early Cretaceous. Moreover, the potential Lower Cretaceous oil and gas system in the pull-apart basin and the vista for its prospecting were explored in this study. Tectonism of the Tanlu fracture was further discussed based on the results of characterization of the basin, and it was pointed out that this is beneficial and instructive to the oil and gas prospecting in Hefei Basin.     

GEOCHEMICAL CHARACTERISTICS OF GRANITES AND ITS STRUCTURAL GENETIC ENVIRONMENT IN THE NANDAN-HECHI METALLOGENETIC BELT, NORTHWEST GUANGXI

The Nandan-Hechi metallogenetic belt is the most important tin-polymetallic producing district in China, and is the location of the Dachang super-large tin deposit. Based on the detailed field investigation and isotopic data, the stages of magmatic activity in the Nandan-Hechi metallogenetic belt have been lined out in this paper. Through the study about the geochemical characteristics of different granites, and by using ω(Al2O3)-ω(SiO2), ω(TFeO)/[ω(TFeO) ω(MgO)]-ω(SiO2), AFM, ACF and Rb-Yb Ta, Rb-Y Nb,Ta-Yb, Nb-Y discrimination diagrams in combination with regional geological setting analysis, the authors carried out analyses about the structural environment for the formation of the granites, and discussed the structural environment and dynamic setting for the large scale mineralization in this area. Our study indicates that the majority of the granites in Nandan-Hechi metallogenetic belt belong to the POG type,while the later stage alaskite belongs to the RRG CEUG type. The granites were formed at the stage of structural transformation from postorogenic phase to intraplate setting. But the major structural environment is characterized by steady regional extension. The formation age for the granites coincides with the time for this transformation, and this translation environment is favored for large-scale metallogenesis.     

GEOCHEMICAL CHARACTERISTICS OF THE EARLY MESOZOIC GRANODIORITES AND THEIR TECTONIC IMPLICATIONS

The early Mesozoic granodiorites (ca. 165 Ma) in the northeastern Hunan Province (NEH) have SiO2=65.4-69.65%, K2O/Na2O=0.95-1.38 and K2O Na2O＞6%, A/CNK=0.96-1.13 and belong to metaluminous high-K calc-alkaline series. They are characterized by LREE and LILEs enrichment, and HFSE depletion with slightly negative Eu anomalies (Eu/Eu*=0.62-0.90). The initial 87Sr/86Sr ratios are in range from 0.711458 to0.717461, and εNd values vary from -9.4 to -12.3, distinct from those of the contemporaneous granodiorites mantle-derived from the Southeastern Hunan Province (SEH) (87Sr/86Sr(i)=0.707962～0.710396, εNd(t)=-6.98～-2.30).By contrast, such signatures are roughly similar to those of the neighboring other Mesozoic granitic plutons (Eu/Eu*=0.30-0.70; 87Sr/86Sr ＞0.710; εNd = -12 to -16) in South China Block (SCB), which have been interpreted as the remelting products of Precambrian basement. The Proterozoic lower-middle crust is an important contributor to the petrogenesis of these early Mesozoic granodiorites in the NEH. An intracontinental extension setting is present in the northeastern Hunan Province at that time due to the demand of enough thermal transfer.     

DISCOVERY OF RADIOLARIAN FOSSILS IN THE CHERT GRAVELS OF TRIASSIC CONGLOMERATE IN THE WEST OF SOUTH TIANSHAN, NW CHINA

1. Introduction Kurgan, a frontier station in the south foot of the Southwest Tianshan Mountains, is located on the NW margin of the Tarim Basin (Fig. 1). The Mesozoic coal-bearing molasses there is the most west Mesozoic outcrop of the Kuqa Depression, a tectonic unit of Tarim and its adjacent area. It is very difficult for geologist to access there. This results in the lack of geological works in this area. Meanwhile, only a few petroleum exploration works have been accomplished in t…     

STRUCTURAL CHARACTERISTICS OF THE TAIHANGSHAN PIEDMONT FAULT ZONE

1. Introduction The Taihangshan piedmont fault zone is located in a transition zone between the Taihang Mountains and the North China Plain, and is an important tectonic zone in North China. It is from the middle of Huairou County of Beijing through Fangshan County of Beijing, Laishui, Baoding, Shijiazhuang, Xingtai, and Handan of Hebei Province, and Anyang and Tangyin of Henan Province to Xinxiang of Henan Province, extending southward about 620 km in a NE-NNE direction (Fig. 1).…     

SEDIMENTARY RESPONSES TO THRUSTING AND STRIKE-SLIPPING OF LONGMEN SHAN ALONG THE EASTERN MARGIN OF TIBETAN PLATEAU AND IMPLICATIONS FOR ACCRETION OF CIMMERIAN CONTINENTS AND INDIA/EURASIA COLLISION

1. Introduction A central goal of stratigraphic studies of foreland basins is to discern which of the possible controls is responsible for vertical trends. In many cases, the primary interest has been to determine the time of deformation in the mountain belt from strata in the foreland basin (Jordan et al., 1988). Traditionally, an active tectonic phase was presumed to cause high relief, and then an immediate flux of coarse sediment into the basin, which produced conglomerates (Longwell, 193…     

MIGRATION OF ALKALINE METAL ELEMENTS POTASSIUM AND SODIUM DURING ZEOLITE MINERALIZING

1. IntroductionClinoptilolite and mordenite, which are two kinds of the most important zeolites used in industry, generally occur in acid volcanic rocks and tectonic basins (mainly faulting depression basin) of the Mesozoic-Cenozoic Era. East China belongs to the Circum-Pacific zeolite mineralization belt. There are abundant zeolite resources (mainly clinoptilolite and/or mordenite) found in this region.Geological characteristics of ore deposits of zeolites and experimental studies of their…