942 resultados para genesis


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The author selected the geological and geochemical characteristics and the genesis of the Dazhuangzi gold deposit in the Pingdu City as the central content of the study. The author summarized geological features of the other gold deposits formed within the same geological setting along the margin of the Jiaolai pull-apart basin and compared these gold deposits with the Dazhuangzi gold deposit. On the basis of the first-hand data obtained from field investigation and from mining production reports, ore-controlling structures, geological characteristics and mineralization regularities of the Dazhuangzi gold deposit are studied in detail. According to the analyzing results of petrochemistry, trace element, rare earth element and fluid inclusion etc., the geochemical characteristics, the genesis and the ore-forming material source of the Dazhuangzi gold deposit and that of the other similar gold deposits along the margin of the Jiaolai Basin are proposed. The study results suggest that the Dazhuangzi gold deposit belongs to the typical interstratified glide breccia type gold deposit, which is controlled by the interstratified glide fault structure located along the margin of the Mesozoic pull-apart Jiaolai basin. The interstratified glide fault structure is in the outer part of unconformity belt between the overlying strata and the basement of the pull-apart basin, being along the marble strata of the Jingshan group. The formation of the ore-controlling structure is related closely with the evolution of the Jiaolai Basin in the Mesozoic. The ore-controlling structure underwent the structural stress changes from compressive to tensional and then to compressive stress with strike slipping features sequentially, which were coincided with the regional tectonic stress evolution. The interstratified glide breccia type gold mineralization mainly occurs in the siliceous-marble breccias and cataclastic rocks within the interstratified glide fault structure. The gold minerogenetic epoch is later than 120Ma when the ore-controlling structure was tensioning and strike-slipping. The occurrences of the ore controlling structure and the gold ore bodies are the same as that of the unconformity belt. The geological and geochemical studies show that the source of the ore-forming material is alike with that of the volcanic rocks of the Qingshan formation, which is widespread in the Jiaolai Basin. Both of them came from the deep crust or even the upper mantle. Based on the geological characteristics and the minerogenetic regularities of the Dazhuangzi gold deposit, a genetic model of the deposit is constructed. In addition, the author used the remote sensing image and exploration results of geochemical and geophysical methods to point out several prospecting areas for further exploration. Through comprehensive study on the interstratified glide fault structure and on the interstratified glide breccia type gold deposits along the Jiaolai pull-apart basin, three types of interstratified glide structures and related gold mineralization are set up according to evolution and distribution of main fault as well as related secondary faults in time and space. They are named as Penjiakuang type, Dazhuangzi type and Fayunkuang type. The author summarized up the minerogenetic characteristics and regularities controlled by these three different types of interstratified glide structures respectively, and set up a general minerogenetic model of the interstratified glide breccia type gold deposit.

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In order to know better about the Phanerozoic lithosphere thinning process of Sino-Korea Plate, four Cretaceous intrusion complexes and their ultramafic xenoliths are investigated by this thesis, which are located in Laiwu, Shandong Province, Eastern China, a region far away from plate margin. The four complexes, Kuanshan, Jiaoyu, Jingniushan and Tietonggou, intruded into Archaeozoic granite gneiss and Paleozoic carbonate rocks with scam iron ore at their contact zone. The four complexes can be divided into two magma series, abyssal rocks for the early and hypabyssal rocks for the later. K-Ar dating show that the abyssal rocks intrusion began with 120 ±2 Ma and the hypabyssal rocks intruded about 113 Ma. Abyssal rocks, mainly made up of augite diorites, amphibole diorites and gabbros for the lesser, are chemically characterized with high-Mg (Mg#>0.5) high-K calcalklic rock, which are depleted with Nb, Ta and Ti related to LILE and extremely enriched with Sr and Pb. Comparatively, augite diorites are the most LREE enriched in abyssal rocks, and they show no Eu abnorrnity or weak positive Eu abnormity. Gabbros show the least LREE enrichment with a strong Eu abnormity relatively. In (~(87)Sr/~(86)Sr)_1 -ε Nd(T) diagram, the abyssal rocks show a mixing trend , a rapid change in ε Nd(T) with a relatively small change in (~(87)Sr/~(86)Sr)_1. Low radiogenic Sr and Pb composition with high radiogeic Nd composition indicate that the mixing processes happened in lower crust Melt-rock interactions in lower crust might be the most possible processes to produce these high-Mg and high-K calcalklic magmas. Hypabyssal rocks, mainly made up of granite porphyry and dioritic porphrite, show much higher ε Nd(T) than abyssal rocks. Granite porphyry are distinct with an adakite geochemical characteristics, high (La/Yb)_N, Sr/Y and low Rb/Sr ratio. The adakitic granite porphyry indicates a new lower crust produced by underplating within plate. Ultramafic xenoliths had been found only in augite diorites and amphibole diorites. Field investigations show that ultramafic xenoliths in augite diorites had been inherited from amphibole diorites, so ultramafic xenoliths had been only entrained by hydrous dioritic magma. Ultramafic xenoliths are mainly made up of dunite and harzburgite, orthopyroxenite and bistangite are the lessor. Coarse olivines in dunite often show many chromite exsolution lamellae. Opx in orthopyroxenite often show dense chromite exsolution lamellae. The presence of exsolution minerals indicates that ultramafic xenoliths had cooled before entraining. Metasomatism phenomenons are popular in dunite and harzburgite xenoliths, including two kinds of assemblage, cpx+phlogapite and opx+pl. The first metasomatism assemblage indicates an ancient enrichment. Rb-Sr dating of xenoliths shows that the ancient enrichment happened in 223 ± 7Ma. The second metasomatism assemblage indicates a recent, relatively not deep melt-rock interaction, which might be related with the genesis of the high-Mg high-K calcalklic rocks. Mineralogy and geochemistry indicate that these ultramafic xenoliths might sample the crust-mante transition zone (or the base of lower crust, moho). Investigation of high-Mg intrusions and their ultramafic xenoliths in Laiwu indicate that the thinning processes of Sino-Korea Plate can be divided into two stages. The first stage is lithosphere mantle thinning with crust thickening by underplating in lower crust. The second stage is that the thickened lower crust delaminated into the underlying mantle.

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This paper builds the model of oil accumulation and achieves the prediction of exploration goal. It uses multiple subject means, the ways of synthetic research and the viewpoint of analyzing genesis, with the academic guidance of sedimentology, structural geology, petroleum geology and geochemistry, the basis of strata sequence frame and structural frame, the frame of "four history" - the burying history, the structural history, the filling history and the evolving history of oil, the masterstroke of hydrocarbon's generation, migration and accumulation, the aim of revealing the genetic relation between mature source rock and oil reservoir in space and time. Some achievements and viewpoints in this study are following. 1. It is proposed that the structural evolution in this area had many periods, and the structural movement of the Xiazijie group telophase formed the structural pattern for the first time. 2. The character of strata sequence in this area is divided by the character of episodic cycle firstly. The study of dividing the facies of single well and the facies of well tie is based on the data of single well. The character of sedimentary facies is con-structed initially. 3. It is believed that Jiamuhe group is the main source rock, which can supply considerable oil and gas resources for the first time. Some criterions of source rock such as the type ,the abundance in Jiamuhe group are analysed. Using the thermal history of source rock, we drawn a conclusion that the original type of source rock in Jiamuhe group is II_1-III, and the abundance achived the level of good source rock, and this set of source rock had contributed to this area. 4. The reservoir strata in this area are assessed and analysed with the reservoir evaluation. There are multi-type reservoirs, such as volcanic lava facies, sedimentary clast facies, continental belch facies. The physical property in reservoir strata is characterized by low porosity and low permeability. The study of diagenetic stage show that the diageneses in Jiamuhe group is A-Bsubage, and the reservoir room is mainly secondary corroded hollow and cleft. 5. The synthetic research on oil system in Jiamuhe group is made for the first time. The type of petroleum system is divided , and we consider that the petroleum system of Jiamuhe group is at the reliable rank. There are two critical time in oil accumulation through studying the critical time of oil accumulation : the early generation of hydrocarbon is oil, and the later is gas. 6. The mechanism of accumulation is analysed. We consider that the accu-mulation of oil in this area has many periods, and the early generated hydrocarbon is expeled by the later , and formed the character of zonal distribution in planar. 7. A bran-new model of oil and gas is proposed. Beneficial enrichment area of oil and gas is analyzed, which can be divided into three sections: Section I can be divided into two sections: I_1 and I_2. The lower subgroup of Jiamuhe is covered by the triassic layer of I_1 section. Fault zone and near the foot wall of fault are charactered with thick phase belt. Then the cover capability in this area is relatively poor, oil can migrate into triassic layer by vertical or lateral migration , and forms I_1 Kelamayi triassic oil pool consequently. The lower subgroup of Jiamuhe is covered by the triassic layer of I_2 section ,which is charactered with thin phase belt. Then the cover capability in this area is relatively good, and forms I_1 Kelamayi triassic oil pool consequently. Section II can be divided into two sections: II_1-I_(I~2). The cover of Jiamuhe group in section II_1 is the low resistivity segment in Wuerhe group, which has thin lithology and poor porosity and permeability. Oil and gas in Jiamuhe group can be covered to form beneficial accumulation area. There are some wells in this area, such as Ke 007 well, 561 well. The thick phase belt layer of Wuerhe high resistivity segment in section II_2 has unconformable relation with Jiamuhe group. The cover ability of the high resistivity segment is poor, petroleum in Jiamuhe can migrate into Wuerhe layer vertically. This area is the beneficial area for accumulating petroleum in Wuerhe layer. there are some wells in this area, such as Ke 75 well, Ke 76 well, Ke 77 well, Ke 78 well, Ke 79 well. Section III can also be divided into two sections: III_1 and III_2. Wuerhe group in section III_1 has unconformable relation with Jiamuhe group. There is thick lithology and poor cover in Wuerhe group, but the strata sequence evolution character of upper subgroup in Jiamuhe group has determined that it has lateral and vertical cover ability. thus, this area is petroleum abundant belt of jiamuhe group, which has the trap. Section III_2 is an area controled by wedgeout of Fengcheng group, Fengcheng group in this area has quite thick lithology so that It has beneficial resevoir phase belt. It can accumulate oil in itself or accept some oil in Jiamuhe group. Jiamuhe group has some oil accumulation condition in this area. Thus, section III_2 is jiamuhe-Fengcheng multiple petroleum accumulation belt, such as Ke 80 well. 8. The goal of exploration is suggested: Depositional trap or combination trap is the important aspect in later exploration. Both types of traps are the goal of the next drilling: Fault block trap in the east of 576 well and the NO. 2 fault block trap in the north of Ke 102 well It is suggested that we should study the law of oil and gas in Jiamuhe group and enhance the study of combination in forming reservoir and trap scale. We do some lithology forecast and reservoir diatropic forecast in order to know the area of oil and gas.

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Natural gas pays more important role in the society as clean fuel. Natural gas exploration has been enhanced in recent years in many countries. It also has prospective future in our country through "85" and "95" national research. Many big size gas fields have been discovered in different formations in different basins such as lower and upper Paleozoic in Erdos basin, Tertiary system in Kuche depression in Tarim basin, Triassic system in east of Sichuan basin. Because gas bearing basins had been experienced multiple tectogenesis. The characteristics of natural gases usually in one gas field are that they have multiple source rocks and are multiple maturities and formed in different ages. There has most difficult to research on the gas-rock correlation and mechanism of gas formation. Develop advanced techniques and methods and apply them to solve above problems is necessary. The research is focused on the critical techniques of geochemistry and physical simulation of gas-rock correlation and gas formation. The lists in the following are conclusions through research and lots of experiments. I 8 advanced techniques have been developed or improved about gas-rock correlation and gas migration, accumulation and formation. A series of geochemistry techniques has been developed about analyzing inclusion enclave. They are analyzing gas and liquid composition and biomarker and on-line individual carbon isotope composition in inclusion enclave. These techniques combing the inclusion homogeneous temperature can be applied to study on gas-rock correlation directly and gas migration, filling and formation ages. Technique of on-line determination individual gas carbon isotope composition in kerogen and bitumen thermal pyrolysis is developed. It is applied to determine the source of natural is kerogen thermal degradation or oil pyrolysis. Method of on-line determination individual gas carbon isotope composition in rock thermal simulation has being improved. Based on the "95"former research, on-line determination individual gas carbon isotope composition in different type of maceral and rocks thermal pyrolys is has been determined. The conclusion is that carbon isotope composition of benzene and toluene in homogenous texture kerogen thermal degradation is almost same at different maturity. By comparison, that in mixture type kerogen thermal pyrolysis jumps from step to step with the changes of maturity. This conclusion is a good proof of gas-rock dynamic correlation. 3. Biomarker of rock can be determined directly through research. It solves the problems such as long period preparing sample, light composition losing and sample contamination etc. It can be applied to research the character of source rock and mechanism of source rock expulsion and the path of hydrocarbon migration etc. 4. The process of hydrocarbon dynamic generation in source rock can be seen at every stage applying locating observation and thermal simulation of ESEM. The mechanism of hydrocarbon generation and expulsion in source rock is discussed according to the experiments. This technique is advanced in the world. 5. A sample injection system whose character is higher vacuum, lower leaks and lower blank has been built up to analyze inert gas. He,Ar,Kr and Xe can be determined continuously on one instrument and one injection. This is advanced in domestic. 7. Quality and quantity analysis of benzene ring compounds and phenolic compounds and determination of organic acid and aqueous gas analysis are applied to research the relationship between compounds in formation water and gas formation. This is another new idea to study the gas-rock correlation and gas formation. 8. Inclusion analysis data can be used to calculate the Paleo-fluid density, Paleo-geothermal gradient and Paleo-geopressure gradient and then to calculate the Paleo-fluid potential. It's also a new method to research the direction of hydrocarbon migration and accumulation. 9. Equipment of natural gas formation simulation is produced during the research to probe how the physical properties of rock affect the gas migration and accumulation and what efficiency of gas migrate and factors of gas formation and the models of different type of migration are. II study is focused on that if the source rocks of lower Paleozoic generated hydrocarbon and what the source rocks of weathered formation gas pool and the mechanism of gas formation are though many advanced techniques application. There are four conclusions. 1.The maturity of Majiagou formation source rocks is higher in south than that in north. There also have parts of the higher maturity in middle and east. Anomalous thermal pays important role in big size field formation in middle of basin. 2. The amount of gas generation in high-over maturity source rocks in lower Paleozoic is lager than that of most absorption of source rocks. Lower Paleozoic source rocks are effective source rocks. Universal bitumen exists in Ordovician source rocks to prove that Ordovician source rocks had generated hydrocarbon. Bitumen has some attribution to the middle gas pool formation. 3. Comprehensive gas-rock correlation says that natural gases of north, west, south of middle gas field of basin mainly come from lower Paleozoic source rocks. The attribution ratio of lower Paleozoic source rocks is 60%-70%. Natural gases of other areas mainly come from upper Paleozoic. The attribution ratio of upper Paleozoic source rocks is 70%. 4. Paleozoic gases migration phase of Erdos basin are also interesting. The relative abundance of gasoline aromatic is quite low especially toluene that of which is divided by that of methyl-cyclohexane is less than 0.2 in upper Paleozoic gas pool. The migration phase of upper Paleozoic gas may be aqueous phase. By comparison, the relative abundance of gasoline aromatic is higher in lower Paleozoic gas. The distribution character of gasoline gas is similar with that in source rock thermal simulation. The migration phase of it may be free phase. IH Comprehensive gas-rock correlation is also processed in Kuche depression Tarim basin. The mechanism of gas formation is probed and the gas formation model has been built up. Four conclusions list below. 1. Gases in Kuche depression come from Triassic-Jurassic coal-measure source rocks. They are high-over maturity. Comparatively, the highest maturity area is Kelasu, next is Dabei area, Yinan area. 2. Kerogen thermal degradation is main reason of the dry gas in Kuche depression. Small part of dry gas comes from oil pyrolysis. VI 3.The K12 natural gas lays out some of hydro-gas character. Oil dissolved in the gas. Hydro-gas is also a factor making the gas drier and carbon isotope composition heavier. 4. The mechanism and genesis of KL2 gas pool list as below. Overpressure has being existed in Triassic-Jurassic source rocks since Keche period. Natural gases were expulsed by episode style from overpressure source rocks. Hetero-face was main migration style of gas, oil and water at that time. The fluids transferred the pressure of source rocks when they migrated and then separated when they got in reservoir. After that, natural gas migrated up and accumulated and formed with the techno-genesis. Tectonic extrusion made the natural gas overpressure continuously. When the pressure was up to the critical pressure, the C6-C7 composition in natural gas changed. The results were that relative abundance of alkane and aromatic decreased while cycloalkane and isoparaffin increased. There was lots of natural gas filling during every tectonic. The main factors of overpressure of natural gas were tectonic extrusion and fluid transferring pressure of source rocks. Well preservation was also important in the KL2 gas pool formation. The reserves of gas can satisfy the need of pipeline where is from west to east. IV A good idea of natural gas migration and accumulation modeling whose apparent character is real core and formation condition is suggested to model the physical process of gas formation. Following is the modeling results. 1. Modeling results prove that the gas accumulation rule under cap layer and gas fraction on migration path. 2. Natural gas migration as free phase is difficult in dense rock. 3. Natural gases accumulated easily in good physical properties reservoirs where are under the plugging layer. Under the condition of that permeability of rock is more than 1 * 10~(-3)μm~(-1), the more better the physical properties and the more bigger pore of rock, the more easier the gas accumulation in there. On the contrary, natural gas canonly migrate further to accumulate in good physical properties of rock. 4. Natural gas migrate up is different from that down. Under the same situation, the amount of gas migration up is lager than that of gas migration down and the distance of migration up is 3 times as that of migration down. 5. After gas leaks from dense confining layer, the ability of its dynamic plug-back decreased apparently. Gas lost from these arils easily. These confining layer can confine again only after geology condition changes. 6. Water-wetted and capillary-blocking rocks can't block water but gases generally. The result is that water can migrate continuously through blocking rocks but the gases stay under the blocking rocks then form in there. The experiments have proved the formation model of deep basin gas.

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The mechanism of gold ore formation in the eastern Tianshan Mountains, Xinjiang Uygur Autonomous Region, that has been dealt with from various aspects, remains unclear. On the basis of investigations of regional geology, ore deposit geology, and microscopic observations of ores and related rocks of the Jinwozi, the 210, and the Mazhuangshan gold ore deposits, this thesis made a systematic research on the microthermometry of gangue quartz-hosted fluid inclusions, gas, liquid ion and rare earth element compositions and hydrogen, oxygen isotope compositions of sulfide- and quartz-hosted fluid inclusions, and sulfur and lead isotope compositions of sulfide ore minerals from the major ores in the three deposits. On the basis of the above synthetic studies, sources of ore-forming fluids and metals, and mechanism of gold ore formation in the region were discussed. Gas compositions of pyrite- and sphalerite-hosted fluid inclusions were first analyzed in this thesis. Compared with gangue quartz-hosted fluid inclusions, the sulfide-hosted ones are richer in gaseous species CO2, CO, and CH4 etc. Both gas and liquid CO2 are commonly observed in fluid inclusions, whereas halite daughter minerals rarely occur. Ore-forming fluids for the three gold ore deposits are characteristically of medium to low temperatures, medium to low salinities, are rich in CO2 and Na+, K+, Cl" ions. Gas covariation diagrams exhibit linear trends that are interpreted as reflecting mixing between the magamtic fluid and meteoric-derived groundwater. Regarding rare earth element compositions, the Jinwozi and the 210 deposits show moderate to strong LREE/HREE fractionations with negative Eu anomalies. However, the Mazhuangshan deposit shows little LREE/HREE fractionation with positive Eu anomalies. Hydrogen and oxygen isotope compositions of pyrite-hosted fluid inclusions that were first analyzed in this thesis indicate the presence of magmatic water. Hydrogen and oxygen isotope compositions of pyrite- and quartz-hosted fluid inclusions suggest mixing between magmatic water and meteoric-derived groundwater. Sulfur and lead isotope compositions of sulfide ore minerals indicate multi-sources for the metallogenetic materials that range from the crust to the mantle. On the basis of the above synthetic studies, genesis of the gold ore deposits in the eastern Tianshan Mountains was approached. From the Middle-Late Hercynian to Early Indosinian, geodynamic regime of the region was changing from the collisional compression to the post-collisional extension. During the period, magmas were derived from the crust and the mantle and carried metallogenetic materials. Magma intrusion in the upper crust released the magmatic fluids, and drove circulation of groundwater. Mixing of magmatic fluid with groundwater, and extraction of metallogenetic materials from the country rocks are the mechanism for the gold ore formation in the eastern Tianshan Mountains.

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The Tiezhai intrusive complex is located in the north of the Luxi block, Shandong province, eastern China. It lies ~30 km west of the Tanlu fault, and is at the cross of the Wujing and Jiushan faults. The Tiezhai complex was formed about 120~130 Ma, when large-scale magmatism was active in eastern part of North China. This paper carries out petrochemical and geochemical study on the Tiezhai intrusive complex, and discusses its genesis in detail. The Tiezhai intrusive complex can be subdivided into three rock series. The first is the gabbro-diorite series formed in early stage. Its composition variation shows 01 and Cpx fractional crystallization trend. The second is the porphyritic diorite and monzonite series, showing dominating Hb fractional differentiation. Their composition variation shows Hb fractional crystallization trend. The third is the porphyritic quartz monzonite with K-feldspar megacrysts, showing weakly Hb and Bi fractional crystallization trend. All types of rocks in the Tiezhai complex are belonging to the high-K cac-alkaline series. They have elevated Sr (450-1660 ppm), Ba (210-1780 ppm) and relatively low Rb (30-100 ppm). For the gabbro-dioritic rocks in the early stage, the abundances of Ni (20-250 ppm), Cr (50-350 ppm), V(l30-250 ppm) and Co (20-40 ppm) are high, indicating a mantle origin. All rocks have negative anormalies of Nb, Ta, Ti and P, and enriched LREE and strong differentiated REE patterns. The porphyritic monzonites and quartz monzonites have very low HREE, Yb and Y contents and positive Eu anormalies, similar to adakite. Most rocks have lowε_(Nd)(t) of-1.5~-10.9, and high (~(87)Sr/~(86)Sr)_i of 0.704~0.709. The data have characters of enriched lithosphere mantle (EMI). In summary, the Tiezhai intrusive complex was inferred to be generated by a mantle derived magma through fractional crystallization. When the primary magma gathered in some place between crust and mantle, the crystallization started and causing magma evolution. The remaining / evolved magma ascended and emplaced again and again in the upper crust in Tiezhai area. Then Tiezhai complex formed. The porphyritic monzonites and quartz monzonites have major and trace element characters of typical adakite, but they are likely to be generated by Hb fractional crystallization.

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These are two parts included in this report. In the first part, the zonation of the complexes in its series, lithofacies, the depth of magma source and chambers is discussed in detailed for the first time based on the new data of petrol-chemistry, isotopes, tectono-magma activity of Mesozoic volcano-plutonic complexes in the southern Great Hinggan Mts. Then, the genetic model of the zonality, double overlapped layer system, is proposed. The main conclusions are presented as follows: The Mesozoic volcanic-plutonic complexes in the southern Great Hinggan were formed by four stages of magma activity on the base of the subduction system formed in late Paleozoic. The Mesozoic magmatic activity began in Meso-Jurassic Epoch, flourished in late Jurassic Epoch, and declined in early Cretaceous Epoch. The complexes consist dominantly of acidic rocks with substantial intermediate rocks and a few mefic ones include the series of calc alkaline, high potassium calc alkaline, shoshonite, and a few alkaline. Most of those rocks are characterized by high potassium. The volcano-plutonic complexes is characterized by zonality, and can be divided mainly into there zones. The west zone, located in northwestern side of gneiss zone in Great Xinggan mountains, are dominated of high potassium basalts and basaltic andesite. The middle zone lies on the southeast side of the Proterozoic gneiss zone, and its southeast margin is along Huangganliang, Wushijiazi, and Baitazi. It composed of dominatly calc-alkaline, high potassium calc-alkaline rocks, deep granite and extrusive rhyolite. The east zone, occurring along Kesheketong Qi-Balinyou Qi-Balinzuo Qi, is dominated of shoshonite. In generally, southeastward from the Proterozoic gneiss zone, the Mesozoic plutons show the zones-mica granitites zone, hornblende-mica granitite zone, mica-hornblende granitite zone; the volcanic rocks also display the zones of calc alkaline-high potassium calc alkaline and shoshonites. In the same space, the late Paleozoic plutons also display the same zonality, which zones are combined of binary granite, granodiorite, quartz diorite and diorite southeast wards from the gneiss. Meso-Jurassic Epoch granite plutons almost distribute in the middle zone on the whole. Whereas late Jurassic Epoch volcanic rocks distribute in the west and east zone. This distribution of the volcano-plutonic complexes reveals that the middle zone was uplifted more intensively then the other zones in Meso-Jurassic and late Jurassic Epoches. Whole rock Rb-Sr isochron ages of the high potassium calc-alkaline volcanic rocks in the west zone, the calc-alkaline and high potassium calc-alkaline granite the middle zone, shoshonite in the east zone are 136Ma, 175Ma and 154Ma, respectively. The alkaline rocks close to the shoshonite zone is 143Ma and 126Ma. The isochron ages are comparable well with the K-Ar ages of the rocks obtained previously by other researchers. The compositions of Sr ans Nd isotopes suggest that the source of Mesozoic volcanic-plutonic complexes in Great Hinggan Mts. is mostly Paleo-Asia oceanic volcanic-sedimentary rocks, which probably was mixed by antiquated gneiss. The tectonic setting for Mesozoic magmatism was subductive continental margin. But this it was not directly formed by present west Pacific subduction. It actully was the re-working of the Paleozoic subduction system( which was formed during the Paleo-Asia ocean shortening) controlled by west Pacific subduction. For this reason, Although Great Hinggan Mts. is far away from west Pacific subduction zone, its volcanic arc still occurred echoing to the volcanic activities of east China, it, but the variation trend of potassium content in volcano-plutonic complexes of Great Hinggan is just reverse to ones of west Pacific. The primitive magmas occurred in the southern Great Hinggan Mts. Include high-potassium calc-alkaline basalt, high potassium calc-alkaline rhyolite, high potassium rhyolite, non-Eu negative anomaly trachy-rhyolite et al. Therefore, all of primitive magmas are either mafic or acid, and most of intermediate rocks occurring in the area are the products of Mesozoic acid magma contaminated by the Paleozoic volcanic- sedimentary rocks. The depth of those primitive magma sources and chambers gradually increase from northwest to southeast. This suggests that Paleozoic subduction still controlled the Mesozoic magmatism. In summary, the lithosphere tectonic system of the southern Great Hinggan Mts. controlling Mesozoic magmatism is a double overlapped layer system developing from Paleozoic subduction system. For this reason, the depth of crust of the southern Great Hinggan Mts. is thicker than that of its two sides, and consequently it causes regional negative gravity abnormity. The second part of this report shows the prolongation of the research work carried on in my doctor's period. Author presents new data about Rb-Sr and Sm-Nd isotopic compositions and ages, geochamical features, genesis mineralogy and ore deposit geology of the volcanic rocks in Kunyang rift. On the base of the substantial work, author presents a prospect of copper bearing magnetite ore deposit. The most important conclusions are as follows: 1. It is proved that all of these carbonatites controlled by a ringing structure system in Wuding-Lufeng basin in the central Yunnan were formed in the Mesoproterozoic period. Two stages could be identified as follows: in the first stage, carbonatitic volcanic rocks, such as lavas(Sm-Nd, 1685Ma), basaltic porphyrite dykes(Sm-Nd, 1645Ma), pyroclastic rocks and volcaniclastic sedimentary rocks, formed in the outer ring; in the second stage, carbonatitic breccias and dykes(Rb-Sr, 1048 Ma) did in the middle ring. The metamorphic age of the carbonatitic lavas (Rb-Sr, 893 Ma) in the outer ring was determined. The magma of carbonatitic volcanic rocks derived mainly form enriched mantle whose basement is depleted mantle that had been metasomated by mantle fluid and contaminated by Archaean lower crust. Carbonatitic spheres were discovered in ore bearing layers in Lishi copper mining in Yimen recently, which formed in calcite carbonatitic magma extrusion. This discovery indicates that the formation of copper ore deposit genesis relates to carbonatitic volcanic activity. The iron and copper ore deposits occurring in carbonatitic volcanic- sedimentary rocks in Kunyang rift results from carbonatitic magmatism. Author calls this kind of ore deposits as subaqueous carbonatitic iron-copper deposit. The magnetic anomaly area in the north of Lishi copper mining in Yimen was a depression more lower than its circumference. Iron and copper ores occurrig on the margin of the magnetic anomaly are volcanic hydrothermal deposit. The magnetic body causing the magnetic anomaly must be magnetite ore. Because the anomaly area is wide, it can be sure that there is a large insidious ore deposit embedding there.

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Various numbers of ancient landslides of various scales are frequently distributed on both banks of reservoirs, especially large reservoirs, both in China and abroad. During inundation and operation of theses reservoirs, some of the landslides are reactivated, which caused losses of people's lives and properties to various extents, some even disasters. Systematic studies are, however, very few on the reservoir-induced reactivation mechanism and development tendency prediction. Based on investigation of reservoir-induced reactivation phenomena of ancient landslides and relevant existing research problems, a systematic study is carried out on the field identification, induced reactivation mechanism, development tendency prediction, risk decision-making and treatment of reservoir-related ancient landslides, through analysis of large numbers of engineering geological investigation results, scientific experimental and research results, in combination with prevention and treatment practices of reservoir-related landslides both in China and abroad, and a series of research results have been obtained. 1. On the basis of study of the distribution features, genesis mechanism of ancient landslides on river banks, a set of scientific methods are summarized on field identification of ancient landslides, and a significant method named "lithologic sequence method" or "indicator layer method", is proposed, which is proved to be very useful. 2. A detail study is made on the reservoir-induced hydraulic effects and material mechanic effects (or softening effects) on the ancient landslide through model and case studies, which concludes that the magnitude and properties of reservoir-induced hydraulic effects are related to the shapes of sliding planes, water content and permeability of landslide materials and variation rate and magnitude of reservoir levels; the magnitude of material mechanic effects are related to the material composition (including mineral composition and grain size), natural water content and saturation state of sliding zones. Also a sensitive analysis is made on the factors that are related to the stabilities of the landslides, which indicate that the stability of a landslide is more sensitive to the groundwater head h_w in the slides and the inner friction angleψof sliding zones than others. 3. The joint inducing mechanism of rainfall and reservoir is also discussed in the paper through model analysis and case study, which proves that reservoir inundation increases firstly the sensitivity of a landslides to rainfall through reduction of its stability or cracking deformation which will increase the rainfall infiltration to the slide body, and then rainfall triggers reactivation or intensifies the reservoir-induced deformation of a landslide. 4. Based on rheologic test results of sliding zones of several reservoir-related ancient landslides, the rheologic characteristics of sliding zones have been discussed in detail and several typical rheologic models have been set up, which well explains the dynamic process of slide deformation. The response types to reservoir inundation and development tendency of reservoir -related ancient landslide are discussed in the paper based on field investigation results. And prediction methods for reservoir-related landslides have been studied based on the Mate-Synthetic principle of quantitative and qualitative analysis, as well as combination of computation and internal mechanism analysis, and a rheologic analytical method is proposed which is proved very useful for prediction of the landslide development tendency. 6. In disaster-prevention and treatment of reservoir-related landslides, risk decision-making has been proved very significant both in engineering and economics. Based on the practices in disaster-prevention and treatment of reservoir-related landslides both in China and abroad, the disaster-prevention risk decision-making for reservoir-related landslides has been proposed in terms of philosophy, methods and procedures, and well put into practice. A summary is also made through case study of the experiences of treatment of reservoir-related landslides both in China and abroad in terms of principle, methods and technical lines. 7 A detail study is made as a case study of the reactivated Maoping ancient landslide on the left bank of the Geheyan Reservoir on Qingjiang river in Hubei province, China, including its field identification features, reservoir-induced reactivation characteristics and mechanism, development tendency prediction and proposed counter measures based on risk analysis.

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By applying multi-discipline theory and methods comprehensively and with full use of computer, the paper deeps into studying changing rule and control factor of fluid field of ES2 Shengtuo oil field during waterflood development, physical and chemical function, and stress. Matrix field, network field, fluid field, stress field and physical chemistry field and fluid model for dynamic function were established. Macroscopic and microscopic genesis mechanics, distribution rule and control factor of remaining oil were revealed. Remaining oil and emulate model were established. Macroscopic and microscopic distribution rule of mover remaining oil were predicted, several results were achieved as following: The distribution of remaining oil was controlled by micro-structure. At the same development stage, remaining oil saturation of the wells located in higher position of micro-structure is higher than the average saturation in the same layer. The water content ratio has same law. It is the enrichment district that the high position of micro-structure controlled by seal faults. The remaining oil distribution was affected by sedimentary micro-facies, micro-structure, fault sealing, reservoir heterogeneity and affusion-oil extraction. On the plane, the zone owning higher saturation of remaining oil is the area that at the edge miacro-facies and sand-body distribution discontinuously; on the section, the content of waterflood of the upper or middle-upper oil layer of positive rhythm and positive comprehensive rhythm is lower, middle and weak waterflood is main, remaining oil is in enrichment relatively. The remaining oil is relative enrichment at the zones of well network of affusion and oil extraction not affected. 4D dynamic model of reservoir of Es2in Shengtuo oil field was established. Macroscopic and microscopic forming mechanics, distribution rule and control factor were revealed. The emulate model of dynamic function of Shengtuo oil field was established, the space distribution of remaining oil were predicted. Reservoir flow field, matrix field, network field, seep field, physical and chemical field, stress field and fluid field models were established. Reservoir flow field character and distribution were revealed. An improvement of the development geology theory in continental fault depression continental basin was brought on.

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The Sawuer gold belt is located in the transition belt between Siberian plate and Kazakhstan-Junggar plate. Based on the geological and geochemical studies on the Kuoerzhenkuola and Buerkesidai gold deposits, in Sawuer gold mineralization belt, the time-space structure of mineralization and mineralizing factor are studied, the metallogenic regularity is concluded in thistheses. The ore bodies have the regularity that orebody are of the extensive and compressive in the sallow and depth of volcanic apparatue, respectively, and the vertical extension of orebody is more intensive than the horizontal extension. The gold deposits were controlled by the fractures of volcanic apparatus and regional faults, and featured by the hydrothermal alteration and metasomatism type disseminated mineralization and filling type vein mineralization. By virtue of the geological and geochemical studies on the two deposits that the formation of the two deposits are significantly related to the volcanic activity, we propose new ideas about their origin: (1) the two deposits are located in the same strata, and share the same genesis. (2) both of two deposits are volcanogenic late-stage hydrothermal gold deposits. Based on mapping of volcanic lithofacies and structure for the first time, it is discovered that a volcanic apparatus existed in the study area. Volcanic-intrusive activity can be divided into three cycles and nine lithofacies. where the two deposits are hosted in the same volcanic cycle, in this case, the wall-rock should belong to the same strata. The 40Ar-39Ar age method is employed in this work to analyze the fluid inclusions of quartz in the ore bodies from Kuoerzhenkuola and Buerkesidai gold deposits. The results show that the main mineralization occurred in 332.05 + 2.02-332.59 + 0.5IMa and 335.53 + 0.32Ma~336.78 + 0.50Ma for Kuoerzhenkuola and Buerkesidai gold deposits respectively, indicating that the two deposits are formed almost at the same time, and the metallogenic epoch of the tow deposits are close to those of the hosting rocks formed by volcanic activity of Sawuer gold belt. This geochronological study supplies new evidence for determining the timing of gold mineralization, the geneses of gold deposits? and identifies that in Hercynian period, the Altai developed tectonic-magmatic-hydrothermal mineralization of Early Carboniferous period, except known two metallogenic mineralization periods including tectonic-magmatic-hydrothermal mineralization of Devonian period and Late Carboniferous-Permian period respectively. The study of fluid inclusions indicates that the ore-forming fluid is a type of NaCl-HbO fluid with medium-low temperature and low salinity, Au is transported by the type of auric-sulfur complex (Au (HS)2-), the ore is formed in reduction condition. Hydrogen and oxygen isotopes of fluid inclusions in the major mineralizating stage show that the solutions mainly originated from magmatic water and meteoric water. The fluid mixing and water-rock reaction cause the deposition of Au. The helium and argon isotope compositions of fluid inclusions hosted in pyrite have been measured from Kuoerzhenkuola and Buerkesidai gold deposits in Sawuer gold belt. The results show that the ore-forming fluids of two deposits possessed the same source and is a mixture of mantle- and partial meteoric water-derived fluid, and the reliability of He and Ar isotopic compositions in Hercynian period is discussed. Isotopic studies including H, O, He, C, S, Pb and Sr reveal the same result that the ore-forming fluids of two deposits possessed the same source: the water derived mainly from magmatic water, partially from meteoric water; the mineralizers and ore materials derived mainly from mantle beneath the island arc, and partially from crust. The ore-forming fluids of two deposits are a mixture of mantle-derived fluids being incorporated by crust-derived fluid, and shallow partial meteoric water. Based on these results, it is proposed that the geneses of the two gold deposits are the same, being volcanogenic late-stage hydrothermal gold deposits that the ore-forming fluids filled in fractures of volcanic apparatus and metasomatized the host rocks in the volcanic apparatus. It is the first time we carried out the geophysical exploration, that is, the EH-4 continuous electrical conductivity image system measurement, the results show that relative large-size mineralizing anomalies in underground have been discovered.lt can confirm the law and genesis of the deposits mentioned above, and change the two abandoned mines to current large-size potenial exploration target.

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By applying synthetically multi-subject theories, methods and technology, such as petroleum geology, sedimentology, seep mechanics, geochemistry, geophysics and so on; and by making full use of computer; combining quantity and quality, macroscopic and microscopic, intensive static and active description, comprehensive studying and physical modeling, 3 dimension and 4 dimension description; the paper took Wen-33 block of Zhongyuan oil field as an example; and studied reservoir macroscopic and microscopic parameter changing rule and evolve mechanics in different water-blood stage. The reservoir dynamic model and remaining-oil distribution mode was established, and several results were achieved as follows: (1) Three types of parameter gaining, optimizing and whole data body of Wen33th reservoir were established. Strata framework, structure framework, reservoir types and distribution of Wen33th reservoir were discussed. Reservoir genesis types, space distribution law and evolve rule of Wen33th reservoir were explained. 4D dynamic model of macroscopic parameter of reservoir flow dynamic geologic function of Wen33th reservoir was established. The macroscopic remaining-oil distribution and control factor was revealed. The models of the microscopic matrix field, pore-throat network field, fluid field, clay mineral field of Wen-33 block were established. The characters, changing rules and controlled factors in different water stage were revealed. The evolve rule and mechanics of petroleum fluid field in Wen-33 block reservoir were revealed. Macroscopic and microscopic remaining oil distribution mode of Wen-33 block were established. Seven types, namely 12 shapes of dynamic model of microscopic remaining oil were discussed, and the distribution of mover remaining oil was predicted. Emulation model: mathematical model and prediction model of Wen-33 block were established. The changing mechanics of reservoir parameter and distribution of remaining-oil were predicted. Firstly, the paper putting forward that the dynamic geologic function of petroleum development is the factor of controlling remaining-oil, which is the main factor leading to matrix field, network field, clay mineral field, fluid field, physic and chemical field, stress field and fluid field forming and evolving. (10) A set of theories, methods and technologies of investigating, describing, characterizing and predicting complex fault-block petroleum were developed.

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Landslides are widely distributed along the main stream banks of the Three Gorges Reservoir area. Especially with the acceleration of the human economic activities in the recent 30 years, the occurrence of landslide hazards in the local area trends to be more serious. Because of the special geological, topographic and climatic conditions of the Three Gorges areas, many Paleo-landslides are found along the gentle slope terrain of the population relocation sites. Under the natural condition, the Paleo-landslides usually keep stable. The Paleo-landslides might revive while they are influenced under the strong rainfall, water storage and migration engineering disturbance. Therefore, the prediction and prevention of landslide hazards have become the important problem involving with the safety of migration engineering of the Three Gorges Reservoir area.The past research on the landslides of the Three Gorges area is mainly concentrated on the stability analysis of individual landslide, and importance was little attached to the knowledge on the geological environment background of the formation of regional landslides. So, the relationship between distribution and evolution of landslides and globe dynamic processes was very scarce in the past research. With further study, it becomes difficult to explain the reasons for the magnitude and frequency of major geological hazards in terms of single endogenic or exogenic processes. It is possible to resolve the causes of major landslides in the Three Gorges area through the systematic research of regional tectonics and river evolution history.In present paper, based on the view of coupling of earth's endogenic and exogenic processes, the author researches the temporal and spacial distribution and formation evolution of major landslides(Volume^lOOX 104m3) in the Three Gorges Reservoir area through integration of first-hand sources statistics, .geological evolution history, isotope dating and numerical simulation method etc. And considering the main formation factors of landslides (topography, geology and rainfall condition), the author discusses the occurrence probability and prediction model of rainfall induced landslides.The distribution and magnitude of Paleo-landslides in the Three Gorges area is mainly controlled by lithology, geological structure, bank slope shape and geostress field etc. The major Paleo-landslides are concentrated on the periods 2.7-15.0 X 104aB.R, which conrresponds to the warm and wettest Paleoclimate stages. In the same time, the Three Gorges area experiences with the quickest crust uplift phase since 15.0X 104aB.P. It is indicated that the dynamic factor of polyphase major Paleo-landslides is the coupling processes of neotectonic movement and Quaternary climate changes. Based on the numerical simulation results of the formation evolution of Baota landslide, the quick crust uplift makes the deep river incision and the geostress relief causes the rock body of banks flexible. Under the strong rainfall condition, the pore-water pressure resulted from rain penetration and high flood level can have the shear strength of weak structural plane decrease to a great degree. Therefore, the bank slope is easy to slide at the slope bottom where shear stress concentrates. Finally, it forms the composite draught-traction type landslide of dip stratified rocks.The susceptibility idea for the rainfall induced landslide is put forward in this paper and the degree of susceptibility is graded in terms of the topography and geological conditions of landslides. Base on the integration with geological environment factors and rainfall condition, the author gives a new probabilistic prediction model for rainfall induced landslides. As an example from Chongqing City of the Three Gorges area, selecting the 5 factors of topography, lithology combination, slope shape, rock structure and hydrogeology and 21 kinds of status as prediction variables, the susceptibility zonation is carried out by information methods. The prediction criterion of landslides is established by two factors: the maximum 24 hour rainfall and the antecedent effective precipitation of 15 days. The new prediction model is possible to actualize the real-time regional landslide prediction and improve accuracy of landslide forecast.

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济阳拗陷(胜利油田)为我国仅次于大庆油田的石油生产基地,区内新生代火成岩广泛发育,且为重要的油气藏储层之一,有关该区火成岩与油气藏的成因联系一直是国内外地学工作极为关注的课题和生产部门亟待解的问题。前人对该区火成岩的研究主要集中在火山岩分布、岩石类型、储层性质等方面,很少涉及对火成岩地球化学、形成构造环境、地幔源区特征、岩浆演化以及在油气形成过程中的作用等方面的研究,对与之时空密切共生的次火山岩——辉绿岩研究相对较少,尤其是岩石地球化学的研究工作尚未开展,无法探讨其成岩动力学背景、地幔地球化学、壳幔相互作用以及与火山岩之间的成因联系等一系列问题。本论文主要对济阳拗陷惠民凹陷钻孔揭露的辉绿岩进行了系统的矿物学和地球化学研究,以此探讨了该区辉绿岩的成岩动力学背景、地幔源区特征、岩浆形成与演化,同时通过与区内沙三段中的火山岩(与辉绿岩时空密切共生)地球化学对比,揭示了辉绿岩与火山岩的成因联系。论文获得的主要认识如下: ① 研究区辉绿岩主要矿物为单斜辉石和斜长石,次要矿物主要为橄榄石、斜方辉石、云母、角闪石、钾长石和方解石等,副矿物主要为磷灰石、金属矿物,同时还出现种类繁多的次生矿物,常见的有蛇纹石、绿泥石、钠长石、高岭石、碳酸盐以及形态不则的云母和金属矿物等;光性测定和探针分析结果表明,各种矿物的化学成分变化范围较宽,可能主要与岩浆结晶分异作用和岩浆期后不同程度的热液蚀变作用有关。 ② 岩石的主要元素、微量元素和稀土元素(REE)的含量范围变化较大,富集高场强元素(HFSE)、具有异常Sr、Nd同位素组成(相对高87Sr/86Sr(0.704094~0.708223)和相对高143Nd/144Nd(0.512604~0.512856))是本区辉绿岩重要的地球化学特征。相关分析结果表明,该区辉绿岩HFSE和REE的含量受磷灰石含量控制,HFSE和REE之间存在较好的正相关关系,证实其HFSE高含量与岩浆地壳物质混染作用有关。 ③ 在一系列岩石分类和类型划分图解上,岩石为钠质碱性系列岩石;岩石具有相似的过渡元素、不相溶元素和REE配分模式,其大离子亲石元素(LILE)、HFSE和REE明显高于原始地幔(PM)和洋中脊玄武岩(MORB);Sr、Nd同位素组成在87Sr/86Sr-143Nd/144Nd图中偏离典型地幔演化趋势,位于DMM与EM2地幔端元之间;成岩环境为大陆板内拉张环境;这些特征均表明本区辉绿岩具有异常地幔源区, 为DMM、EM1和EM2三端元混合的混合地幔。 ④ 研究区辉绿岩与区内沙三段中的火山岩具有相似的主要元素、微量元素、稀土元素和Sr-Nd同位素组成,过渡元素、不相容元素和REE配分模式不具明显区别,微量元素之间的比值变化范围重叠、且与交代富集地幔端元(EM1和EM2)相近,这些均表明两类岩石为同源不同岩相的产物,辉绿岩为火山岩为次火山岩相。 ⑤ 结合有关模拟计算结果,初步建立了研究区辉绿岩成因模式。新生代,随着太平洋板块向西俯冲,引发北东向郯庐深大断裂带的重新活动,俯冲进行地幔楔中的沉积物脱水形成的流体和沿郯庐深大断裂带上升的地幔深部流体与亏损地幔相互作用,形成该区具DMM、EM1和EM2三端元混合特征的异常地幔;这种异常地幔部分熔融形成的熔体(原始岩浆)在岩浆房(或上升过程中)遭受地壳物质的混染作用,形成本区辉绿岩和火山岩的母岩浆;大部分母岩浆沿区内构造薄弱地带快速喷发形成本区的火山岩,少量喷发速度较慢的岩浆结晶形成次火山岩相的辉绿岩。