东天山红山高硫型浅成低温铜-金矿床氧化带的形成机理和硫酸盐矿物的系列发现及意义

Located in the Paleozoic uplift along the southern margin of Tu-Ha basin in eastern Xinjiang, the newly discovered Hongshan Cu-Au deposit occurs in the superimposed Mesozoic volcanic basin upon the north section of later Paleozoic Dananhu-Tousuquan accretionary arc. Kalatage Cu-Au orebelt is controlled by NWW-trend faults, and includes Hongshan and Meiling Cu-Au deposits. The host rocks of Hongshan ore district are mainly rhyolitic-dacitic ignimbrites, whereas Cu-Au mineralization is closely related to quartz porphyry, rhyolitic porphyry and granitic porphyry. Mineralization styles are dominantly veinlet-disseminated and veinlet, occasionally stockwork. The mineral association is chalcopyrite, pyrite, bornite, chalcocite and sphalerite. The hydrothermal alteration consists of silicfication, sericitization, alunitization, pyrophylitization, illitization, hydromuscovitization, and chloritization. Hongshan Cu-Au deposit, on the edge of the desert, is one of the driest areas in eastrn Tianshan. Moreover， the highest temperature has been up to 60℃, and the average rainfall receives only 34.1mm/y. The light rainfall and rapid evaporation in the vicinity of this deposit have allowed the formation of a great variety of water-soluble sulfates. Oxidization zone of this deposit lies on the upper part of primary sulfide orebodies appearing with a depth of 50-60m, which is dominant in sulfate minerals. 1. Based on the field observation, the volcanic and sub-volcanic rock composition, hydrothermal alteration, ore structure and mineralization characteristics, this paper proposed that the Hongshan Cu-Au deposit belongs to a transitional type from high-sulfide epithermal to porphyry Cu-Au deposit, which corresponds with the typical HS-epithermal deposit such as Zijinshan Au-Cu deposit in Fujian Province, SE-China. 2. The Hongshan copper-gold deposit was controlled by the tectonic, stratum, magma activity and volcanic apparatus, whereas Au mineralization is closely related to quartz porphyry, rhyolitic porphyry and fine grained pyritization in hydrothermal activity, and Cu mineralization is closely related to quartz porphyry and hydrothermal explosive breccia. 3. Oxidation zone of Hongshan Cu-Au deposit lies on the upper part of primary sulfide orebodies deposit. 23 sulfate minerals were identified in this work. The results of samples XRD and chemical analysis were furthermore confirmed through thermal, infrared spectrum and mössbauer spectrum analysis. Among those, nine minerals as Ferricopiapite, Cuprocopiapite, Rhomboclase, Parabutlerite, Krausite, Yavapaiite, Metasideronatrite Kroehnkite and Paracoquimbite were founded in China for the first time. And Paracoquimbite was secondly reported in the world (first case reported at 1938 in Chile). 4. EPMA analysis shows that Al impurity in crystal lattice is important to polytype formation of paracoquimbite and coquimbite besides stack fault. 5. Compared with Meiling Cu-Au deposit in the same Kalatage ore belt from the characteristics of δ34S of barite, lithofacies, hydrothermal alteration and homogeneous temperature, Hongshan Cu-Au deposit belongs to the same metallogenic system of HS-epithermal type as Meiling Cu-Au deposit. But Hongshan Cu-Au deposit has less extensive alteration and shallower denudation. 6. Sulfur isotope analyses show that δ34S values of pyrites vary in the range of +1.86‰~+5.69‰, with an average of 3.70‰, mostly in the range of +1.86‰~+3.20‰, and δ34Scp<δ34Spy. Therefore ore-forming fluid of porphyry comes from mantle and was contaminated by the earth’s crust. Sulfur isotope has reached balance in ore-forming process. 7. Sulfur isotope analyses show that δ34S values of sulfates vary in the range of +2.15‰~+6.73‰, with an average of +3.74‰, mostly equals as δ34S values of primary sulfides in Hongshan Cu-Au deposit. So supergene sulfates inherit sulfur of primary sulfide. δ34S values are mostly same in different sulfates. As well as pyrite and chalcopyrite, volcanic hot spring and associated native sulfur underground also provide water medium and sulfur during the formation process of sulfate. 8. According to the EPMA of sample chalcopyrite and pyrite in Hongshan Cu-Au, the value of Cu/Ni is 0.98-34.72, mostly close to the value of 5, which shows that Hongshan deposit is a typical volcanogenic magmaic hypothermal deposit. Au and Ag, Zn, Te and Bi are positive correlation, Cu and Hg, Se, Sb are positive correlation, indicates Au and Cu don’t locate in the factor of mineralization of same mineralization groups. The reasons of gold concentration in the oxidation zone are: 1). Change of redox potential (Eh) makes gold to deposit from the liquid of mineralization zone; 2). PH is one of the most factors of gold’s deposition; 3). Soluble complex and colloid of gold can be adsorbed easily. 9. The biotite and hornblende K-Ar isotopic ages from the wall rock－quartz diorite, biotite granite and monzonite granite are 231.99±3.45Ma, 237.97±2.36Ma and 296.53±6.69Ma respectively. The ore-bearing rhyolitic breccia lava contains breccia of the biotite granite which indicates the volcanism and related Cu-Au mineralization occurred later than the granite, possibly in Mesozoic. K-Ar ages of granitoids in Sanya, Baishiquan and Hongliugou area and Molybdenite Re-Os age of Baishan Mo deposit all are in Triassic. Besides late Paleozoic magmatism, igneous magmatic event of Mesozoic was widespread in eastern Tianshan. 10. The K-Ar age dating indicates that the K-Ar age of Voltaite occurred below surface 1m is 56.02±3.98Ma, K-Ar age of Ferricopiapite occurred below surface 1.5m is 8.62±1.12Ma, K-Ar age of Yavapaiite occurred below surface 14 m is 4.07±0.39Ma, and K-Ar age of Voltaite occurred below surface 10 m is 14.73±1.73Ma. So the age interval of oxidation zone of Hongshan copper-golden bed is between 60 -3.38Ma. Oxidization occurred at Caenozoic era (from 65Ma), which can be identified through comparing with different deposits oxidation zone in other countries. The coupling between global tectonic event and climatic change event which occur from Caenozoic era has some effect on epigeosphere system, which can act on the surface of bed oxidation zone similarly. It induces that the age mentioned above coincide with collision of India-Asia and multistage uplifting of Qinhai-Tibet Plateau happened subsequently. Bed oxidation zone is the effect and record of collision and uplifting of Tibet Plateau. The strong chemical weathering of surface accumulation to which was leaded by PETM event occurred Paleocene and Eocene is the reason of Voltaite sharply rises. On the contrary, Ferricopiapite formed due to the global cold weather. The predecessor did much research through biota, isotopes, susceptibility, but this paper try to use different sulfate mineral instead of climatic change. So the research of sulfate minerals not only indicates a great deal of oxidized zone feature, but also the intergrowth of sulfate minerals may be used to trace paleoenviroment and paleoclimate of oxidation zone. 11. Analysis of the information of alteration and mineralization features of four bore cores, induced activity polarization well logging and Eh-4 geophysical section, deep mineralization anomaly objects of Hongshan ore districts shows low resistance, middle and high polarization, measurements of Eh-4 consecutive conductance section show the existing of concealed porphyry ore body deeper than 450m, on the top of and around rock body there are low resistance body ranged from 100-300Ω•m, this area may be the ore-bearing part. In a word, Hongshan Cu-Au deposit deposit is a combine of upper HS-style epithermal Au deposit and deeper porphyry mineralization system. It has great potential to find large HS-style epithermal-porphyry Au-Cu deposits. This paper consists of seven chapters and twenty seven sections. The geological character of deposit is basic condition in this work. Constitute of oxidation zone, research of sulfate mineral, relation between oxidation and primary zone, K-Ar ages of potassic sulfate are key parts of thesis. Genesis of ore deposit is the further expansion of this research. Analysis of ore-controlling factors is the penetration above basic. Analysis of potential is application of exploration.

北山及邻区古生代-早中生代增生与碰撞大地构造格局

The Beishan orogenic collage locates at the triple-joint among Xinjiang, Gansu, and Inner Mongolia Provinces, at which the Siberian, Tarim and North China plates join together. It also occupies the central segment of the southern Central Asian Orogenic Belt (CAOB). The main study area in the present suty focused on the southwest part of the Beishan Mountain, which can be subdivided into four units southernward, the Mazhongshan continental block, Huaniushan Arc, Liuyuan suture zone and Shibanshan-Daqishan Arc. 1. The Huaniushan Arc was formed by northernward dipping subduction from the Orcovician to Permian, in which volcanic rocks ranging from basic to acidic with island arc affinity were widely developed. The granitiod intrusions become smaller and younger southward, whichs indicates a southward rollback of slab. The granitiod intrusions are mainly composed of I type granites, and their geochemical compositions suggest that they have affinities of island arc settings. In the early Paleozoic（440Ma-390Ma）. The Shibanshan-Daqishan Arc, however, were produced in the southernward dipping subduction system from Carboniferous to Permian. Volcanic rocks from basic to acidic rocks are typical calcic-alkaline rocks. The granitiod intrusions become smaller and younger northernward, indicating subdution with a northernward rollback. The granitiod intrusions mainly consist of I-type granites, of which geochemical data support they belong to island arc granite. 2. Two series of adakite intrusions and eruptive rocks have been discovered in the southern margin of the Huaniushan Island Arc. The older series formed during Silurian (441.7±2.5Ma) are gneiss granitoid. These adakite granites intruded the early Paleozoic Liuyuan accretionary complex, and have the same age as most of the granite intrusions in the Huanniushan Arc. Their geochemical compostions demonstrate that they were derived from partial melting of the subudcted oceanic slab. These characteristics indicate a young oceanic crust subduction in the early Paleozoic. The late stage adakites with compositons of dacites associate with Nb-enriched basalts, and island arc basalts and dacites. Their geochemistries demonstrate that the adakites are the products of subducted slab melts, whereas the Nb-enriched basalt is products of the mantle wedge which have metasomatized by adakite melts. Such a association indicates the existences of a young ocean slab subduction. 3. The Liuyuan suture zone is composed of late Paleozoic ophiolites and two series of accretionary complexes with age of early Paleozoic. The early Paleozoic accretionary complex extensively intruded by early Palozioc granites is composed of metamorphic clastics, marble, flysch, various metamorphic igneous rocks (ultramafic, mafic and dacite), and eclogite blocks, which are connected by faults. The original compositions of the rocks in this complex are highly varied, including MORB, E-MORB, arc rocks. Geochronological study indicates that they were formed during the Silurian (420.9±2.5Ma and 421.1±4.3Ma). Large-scale granitiods intruded in the accretionary complex suggest a fast growth effect at the south margin of the Huaniushan arc. During late Paleozoic, island arc were developed on this accretionary complex. The late Paleozoic ophiolite has an age of early Permian (285.7±2.2Ma), in which the rock assemblage includes ultra-mafic, gabbros, gabbros veins, massive basalts, pillow basalt, basaltic clastic breccias, and thin layer tuff, with chert on the top.These igneous rocks have both arc and MORB affinities, indicating their belonging to SSZ type ophiolite. Therefore, oceanic basins area were still existed in the Liuyuan area in the early Permian. 4. The mafic-ultramafic complexes are distributed along major faults, and composed of zoned cumulate rocks, in which peridotites are surrounded by pyroxenite, hornblendites, gabbros norite and diorite outward. They have island-arc affinities and are consistent with typical Alaska-type mafic-ultramafic complexes. The geochronological results indicate that they were formed in the early Permian. 5. The Liuyuan A-type granite were formed under post-collisional settings during the late Triassic (230.9±2.5Ma), indicating the persistence of orogenic process till the late Triassic in the study area. Geochronological results suggested that A-type granites become younger southward from the Wulungu A-type granite belt to Liuyuan A-type granite belt, which is in good agreement with the accretionary direction of the CAOB in this area, which indicate that the Liuyuan suture is the final sture of the Paleo-Asin Ocean. 6. Structural geological evidence demonstrate the W-E spreading of main tectonic terrenes. These terrenes had mainly underwent through S-N direction contraction and NE strike-faulting. The study area had experienced a S-N direction compression after the Permian, indicating a collisional event after the Permian. Based on the evidene from sedimentary geology, paleontology, and geomagnetism, our studies indicate that the orogenic process can be subdivided into five stages: (1) the pre-orogenic stage occurred before the Ordovicain; (2) the subduction orogenic stage occurred from the Orcovician to the Permian; (3) the collisional orogenic stage occurred from the late Permian to the late Triassic; (4) the post-collision stage occurred after the Triassic. The Liuyuan areas have a long and complex tectonic evolutional history, and the Liuyuan suture zone is one of the most important sutures. It is the finally suture zone of the paleo-Asian ocean in the Beishan area.

东准噶尔和尔赛斑岩铜矿特征及其形成的构造背景

Hersai porphyry copper deposit(PCD) of eastern junggar, newly discovered copper deposit, is located at the eastern segment of the Xiemisitai-Kulankazigan-Zhifang-Qiongheba Paleozoic island arc, Eastern Junggar. The Hersai PCD is developed in a intrusive complex, characterized by intensive and multiform hydrothermal alteration, including potassic alteration, silification, chloritization，sericitization，kaolinitization and carbonatization. Granodiorite, grandiorite porphyry, granite and concealed explosion breccia are hosts of the ore bodies containing veinlet and disseminated ore. Ore-bearing granite (ZK107-1-9), granodiorite (ZK107-1-9) and Ore-barren granodiorite (HES2-1) are selected to date zircon U-Pb age by SHRIMP method, and have an age of 429.4±6.4Ma ,413.0±3.4Ma and 411.1±4.8Ma, respectively, showing that they were emplaced from Late Silurian to Early Devonian. In addition, sample ZK107-1-9 has some hydrothermal zircons with a weighted mean 206Pb/238U age of 404.9±3.7Ma which is interpreted to be related to the granodiorite porphyry. Re-Os dating of five molybdenite samples yielded a weighted average model age of 408.0±2.9Ma, indicating the metallogenic epoch of the Hersai PCD. The ore-forming age is close to the petrogenic time of garnodiorite (411-413Ma), this suggests the ore-forming porphyry is most possiblely granodiorite porphyry. Systematic major - trace elements and Rb-Sr-Sm-Nd-Pb-Hf isotopic characteristics were studied. Analysis results show that these intrusives have some interesting and special characteristics, as following:1) containing both calc-alkaline rocks and high potassium calc-alkaline rocks ; 2) have some characteristics of adakite, but not totally, such as much lower La/Yb ratios and no Eu anomaly or just faint Eu anomaly; 3) have an initial 87Sr/86Sr ratios(0.703852-0.704565) similar to that of BSE, positive εNd(t) values between 6.1 and 7.4, the initial 206Pb/204Pb values (17.576-17.912), 207Pb/204Pb values (15.400-15.453) , 208Pb/204Pb values (37.252-37.466) , and high εHf(t) values (10.2-15.4) close to the value of depleted mantle. These geochemical features suggest that these igneous rocks in the Hersai area not only have some characteristics of island arc, but also some characteristics that only appear in the continental margin arc. It is suggested that Hersai PCD is formed in the subduction setting by the partial melting of young crust. These works and advancements mentioned in the paper are helpful to understand the deposit geology, geochemistry and metallogenesis of Hersai PCD. It is also significant to understand mineralization and tectonic setting in the Qiongheba area.

藏北可可西里碰撞后钾质火山作用和岩石成因

Post-collisional, potassic igneous rocks are widely distributed in the Hoh Xil area of the northern Tibetan Plateau. Based on the field work, petrography, mineral chemistry, K-Ar geochronology, element and Sr-Nd-Pb isotope geochemistry, this thesis systematically studied the spatial and temporal distribution of the volcanic rocks, chemical characteristics, formation mechanism and partial melting mechanism of the magma source region, geodynamic setting of magmatism, as well as crustal assimilation and fractional crystallization (AFC). The results show that: 1. The Miocene (7.77-17.82 Ma) volcanic products dominantly are trachandesite and trachy, and subordinate rhyolites, associated with stike-slip faults and thrust faults, formed morphology of small lava platforms and cinder cones. 2. Phenocrysts in the lavas are augite, andesine, sanidine, calcic amphibole and subordinate orthopyroxene, biotite and Ti-Fe oxides, displaying typical quench texture. Equilibrium temperatures and pressures of clinopyroxene phenocrysts indicate the magma chamber is located in upper-middle crust. 3. Rhyolites are the products of crustal melting and fractionation of shoshonitic magmas. The source region of intermediate magmas is enriched continental lithospheric mantle, which contains residual minerals such as phlogopite, rutile and spinel, and enriched by subducted sediments during earlier multi-episodes of subduction. 4. Upwelling of asthenosphere provides heat for source region melting, and faults provide channels for magma eruption. 5. Northward underthrusting of Indian continental lithosphere and southward of backstop of Asian continental lithosphere resulted in upwelling of hot asthenosphere. Geochemical characteristics of the potassic magmatism in North Tibet are dominantly controlled by source region composition, partial melting, and crustal assimilation and fractional crystallization (AFC).

沾化凹陷火成岩油气藏形成条件和分布规律研究

As a kind of special lithologic ones, Igneous rock oil and gas pool is more and more paid attention, and it has different forming condition and distribution from conventional ones, such as various terrane distribution types, serious reservoir anisotropy, complicated hydrocarbon-bearing, so there is not successful experience to follow for exploration and development of this complex subtle oil and gas pool at present. For an example of Igneous oil and gas pool of Luo151 area in Zhanhua seg, Eastern China, this article study the difficult problem, including petrologic nd lithofacies analysis, Origin, invasion age and times of Igneous rock, reservoir anisotropy, Geological Modeling, Igneous reservoir synthesis evaluation. forming condition and distribution are studied synthetically, and an integrated method to predict igneous rock oil and gas pool is formed, which is evaluated by using development data. The Igneous rock is mainly diabase construction in Luo151 area of Zhanhua Sag, and petrologic types include carbonaceous slate, hornfels, and diabases. Based on analyzing synthetically petrologic component, texture and construct, 4 lithofacies zones, such as carbonaceous slate subfacies, hornfels subfacies containing cordierite and grammite, border subfacies and central subfacies, are divided in the diabase and wall rock. By studying on isotopic chronology, terrane configuration and imaging logging data, the diabase intrusion in Zhanhua Sag is formed by tholeiite magma emplacing in Shahejie formation stratum on the rift tension background Lower Tertiary in North China. The diabase intrusion of Luo151 is composed possibly of three periods magma emplacement. There is serious anisotropy in the diabase reservoirs of Luo151 in Zhanhua Sag. Fracture is primary reservoir space, which dominated by tensile fracture in high obliquity, and the fracture zones are mainly developed round joint belt of igneous rock and wall rock and position of terrane thickness changing rapidly. The generation materials of the reservoirs in Luo151 igneous oil pools consist of Intergranular micropore hornfels, condensate blowhole-solution void diabase condensate edge, the edge and center of the condensate seam diabase, of which are divided into horizontal, vertical and reticulated cracks according fracture occurrence. Based on the above research, a conceptual model of igneous rock reservoir is generated, which is vertically divided into 4 belts and horizontally 3 areas. It is built for the first time that classification evaluation pattern of igneous rock reservoir in this area, and 3 key wells are evaluated. The diabase construction is divided into grammite hornfels micropore type and diabase porous-fracture type reservoirs. The heavy mudstone layers in Third Member of Shahejie formation (Es3) provide favorable hydrocarbon source rock and cap formation, diabase and hornfels belts serve as reservoirs, faults and microcracks in the wall rocks as type pathways for oil and gas migration. The time of diabase invasion was about in the later deposition period of Dongying Formation and the middle of that of Guantao Formation, the oil generated from oil source rock of Es3 in the period of the Minghuazhen formation and is earlier more than the period of diabase oil trap and porous space forming. Based on geological and seismic data, the horizon of igneous rocks is demarcated accurately by using VSP and synthetic seismogram, and the shape distribution and continuity of igneous rocks are determined by using cross-hole seismic technology. The reservoir capability is predicted by using logging constraining inversion and neural network technology. An integrated method to predict igneous rock oil and gas pool is formed. The study is appraised by using development data. The result show the reservoir conceptual model can guide the exploration and development of oil pool, and the integrated method yielded marked results in the production.

济阳-昌潍坳陷火成岩油气藏体系形成机理和分布规律研究

Jiyang & Changwei depressions are two neighboring depressions in Bahai Bay Basin, the famous oil rich basin in East China. The exploration activities in the past 40 years has proved that, within the basins, there exists not only plentiful sandstone hydrocarbon reservoirs (conventional), but also abundant special reservoirs as igneous rock, mudstone and conglomerate ones which have been knowing as the unconventional in the past, and with the prospecting activity is getting more and more detailed, the unconventional reservoirs are also getting more and more important for further resources, among which, the igneous lithological reservoir be of significance as a new research and exploration area. The purpose of this paper is, with the historical researches and data as base, the System Theory, Practice Theory and Modern Comprehensive Petroleum Geology Theory as guide, the theoretical and practice break through as the goal, and the existing problems in the past as the break through direction, to explore and establish a valid reservoir formation and distribution models for igneous strata in the profile of the eastern faulted basins. After investigating the distribution of the igneous rocks and review the history of the igneous rocks reservoirs in basins, the author focused on the following issues and correspondingly the following progresses have been made: 1.Come to a new basin evolution and structure model named "Combined-Basin-bodies Model" for Jiyang even Eastern faulted basins based on the study on the origin and evolution of Jiyang & Changwei basins, depending on this model, every faulted basin in the Bo-hai Bay Basin is consisted of three Basin-Bodies including the Lower (Mesozoic), Middle (Early Tertiary) and the Upper (Late Tertiary) Bodies, each evolved in different geo-stress setting and with different basin trend, shape and igneous-sedimentary buildings system, and from this one to next one, the basin experienced a kind of process named "shape changing" and "Style changing". 2. Supposed a serious of new realizations as follows (1) There were "multi-level magma sources" including Upper mantel and the Lower, Middle and even the Upper Shell magma Chambers in the historical Magma Processes in the basins; (2) There were "multi-magma accessing or pass" from the first level (Mantel faults) to the second, third and fourth levels (that is the different levels of fault in the basin sediment strata) worked in the geo-historical and magma processes; (3) Three tectonic magma cycles and more periods have been recognized those are matched with the "Basin -body-Model" and (4)The geo-historical magma processes were non-homogeneous in time and space scale and so the magma rocks distributed in "zones" or "belts". 3. The study of magma process's effect on basin petroleum conditions have been made and the following new conclusions were reached: (1) the eruptive rocks were tend to be matched with the "caped source rock", and the magma process were favorable to the maturing of the source rocks. (2) The magma process were fruitful to the accumulation of the non-hydrocarbon reservoirs however a over magma process may damage the grade of resource rock; (3) Eruptive activity provided a fruitful environment for the formation of such new reservoir rocks as "co-eruptive turbidity sandstones" and "thermal water carbonate rocks" and the intrusive process can lead to the origin of "metamorphism rock reservoir"; (4) even if the intrusive process may cause the cap rock broken, the late Tertiary intrusive rocks may indeed provide the lateral seal and act as the cap rock locally even regionally. All above progresses are valuable for reconstructing the magma-sedimentary process history and enriching the theory system of modem petroleum geology. 4. A systematic classification system has been provided and the dominating factors for the origin and distribution of igneous rock reservoirs have been worked out based on the systematic case studies, which are as follows: (1) The classification is given based on multi-factors as the origin type, litho-phase, type of reservoir pore, reservoir ability etc., (2) Each type of reservoir was characterized in a detailed way; (3) There are 7 factors dominated the intrusive reservoir's characteristics including depth of intrusion, litho-facies of surrounding rocks, thickness of intrusive rock, intrusive facies, frequency and size of the working faults, shape and tectonic deformation of rock, erosion strength of the rock and the time of the intrusion ect., in the contrast, 4 factors are for eruptive rocks as volcanic facies, frequency and size of the working faults, strength of erosion and the thermal water processing. 5. Several new concept including "reservoir litho-facies", "composite-volcanic facies" and "reservoir system" ect. Were suggested, based on which the following models were established: (1) A seven reservoir belts model for a intrusive unit profile and further more, (2) a three layers cubic model consisted of three layer as "metamorphic roe layer", "marginal layer" and "the core"; (3) A five zones vertical reservoir sequence model consisted of five litho-facies named A, B, C, D and E for a original lava unit and furthermore three models respectively for a erosion, subsidence and faulted lava unit; (4) A composite volcanic face model for a lava cone or a composite cone that is consisted of three facies as "crater and nearby face", "middle slope" and "far slope", among which, the middle slope face is the most potential reservoir area and producible for oil & gas. 6. The concept of "igneous reservoir" was redefined as the igneous, and then a new concept of "igneous reservoir system" was supposed which means the reservoir system consisted of igneous and associated non-igneous reservoirs, with non-hydrocarbon reservoir included. 7. The origin and distribution of igneous reservoir system were probed and generalized for the exploration applications, and origin models of the main reservoir sub-systems have been established including those of igneous, related non-igneous and non-hydrocarbon. For intrusive rocks, two reservoir formation models have been suggested, one is called "Original or Primary Model", and the another one is "Secondary Model"; Similarly, the eruptive rock reservoirs were divided in three types including "Highly Produced", "Moderately Produced" and "Lowly Produced" and accordingly their formation models were given off; the related non-igneous reservoir system was considered combination of eight reservoirs, among which some ones like the Above Anticline Trap are highly produced; Also, the non-hydrocarbon. Trap system including five kinds of traps was discussed. 8. The concept models for four reservoir systems were suggested, which include the intrusive system consisted of 7 kinds of traps, the land eruptive system with 6 traps, the under water eruptive system including 6 kinds of traps and the non-hydrocarbon system combined by 5 kinds of traps. In this part, the techniques for exploration of igneous reservoir system were also generalized and probed, and based on which and the geological progresses of this paper, the potential resources and distributions of every reservoir system was evaluated and about 186 millions of reserves and eight most potential non-hydrocarbon areas were predicted and outlined. The author believe that the igneous reservoir system is a very important exploration area and its study is only in its early stage, the framework of this paper should be filled with more detailed studies, and only along way, the exploration of igneous reservoir system can go into it's really effective stage.

火成岩储层裂缝识别、预测理论与方法研究－以济阳坳陷火成岩油藏为例

Since 1970s, igneous reservoirs such as Shang741, Bin674 and Luol51 have been found in Jiyang depression, which are enrichment and heavy-producing. Showing good prospect of exploration and development, igneous reservoirs have been the main part of increasing reserves and production in Shengli oilfield. As fracture igneous reservoir being an extraordinary complex concealed reservoir and showing heavy heterogeneity in spatial distribution, the study of recognition, prediction, formation mechanism and the law of distribution of fracture is essential to develop the reservoir. Guided by multiple discipline theory such as sedimentology, geophysics, mineralogy, petroleum geology, structural geology and reservoir engineering, a set of theories and methods of recognition and prediction of fractured igneous rock reservoir are formed in this paper. Rock data, three-dimensional seismic data, log data, borehole log data, testing data and production data are combined in these methods by the means of computer. Based on the research of igneous rock petrography and reservoir formation mechanism, emphasized on the assessment and forecast of igneous rock reservoir, aimed at establishing a nonhomogeneity quantification model of fractured igneous rock reservoir, the creativity on the fracture recognition, prediction and formation mechanism are achieved. The research result is applied to Jiyang depression, suggestion of exploration and development for fractured igneous rock reservoir is supplied and some great achievement and favourable economic effect are achieved. The main achievements are gained as follows: 1. The main facies models of igneous rock reservoir in JiYang depression are summarized. Based on data and techniques of seism, well log and logging,started from the research of single well rock facies, proceeded by seismic and log facies research, from point to line and line to face, the regional igneous facies models are established. And hypabyssal intrusion allgovite facies model, explosion volcaniclastic rock facies model and overfall basaltic rocks facies model are the main facies models of igneous rock reservoir in JiYang depression. 2. Four nonhomogenous reservoir models of igneous reservoirs are established, which is the base of fracture prediction and recognition. According to characteristics of igneous petrology and spatial types of reservoir, igneous reservoirs of Jiyang depression are divided into four categories: fractured irruptive rock reservoir, fracture-pore thermocontact metamorphic rock and irruptive rock compound reservoir, pore volcanic debris cone reservoir and fracture-pore overfall basaltic rock reservoir. The spatial distribution of each model's reservoir has its features. And reservoirs can be divided into primary ones and secondary ones, whose mechanism of formation and laws of distribution are studied in this paper. 3. Eight geologic factors which dominate igneous reservoirs are presented. The eight geologic factors which dominates igneous reservoirs are igneous facies, epigenetic tectonics deformation, fracture motion, intensity of intrusive effect and adjoining-rock characters, thermo-contact metamorphic rock facies, specific volcano-tectonic position, magmatic cyclicity and epigenetic diagenetic evolution. The interaction of the eight factors forms the four types nonhomogenous reservoir models of igneous reservoirs in Jiyang depression. And igneous facies and fracture motion are the most important and primary factors. 4. Identification patterns of seismic, well log and logging facies of igneous rocks are established. Igneous rocks of Jiyang depression show typical reflecting features on seismic profile. Tabular reflection seismic facies, arc reflection seismic facies and hummocky or mushroom reflection seismic facies are the three main facies. Logging response features of basic basalt and diabase are shown as typical "three low and two high", which means low natural gamma value, low interval transit-time, low neutron porosity, high resistivity and high density. Volcaniclastic rocks show "two high and three low"-high neutron porosity, high interval transit-time, low density, low-resistance and low natural gamma value. Thermo-contact metamorphic rocks surrounding to diabase show "four high and two low" on log data, which is high natural gamma value, high self-potential anomaly, high neutron porosity, high interval transit-time and low density and low-resistance. Based on seismic, well log and logging data, spatial shape of Shang 741 igneous rock is described. 5. The methods of fracture prediction and recognition for fractured igneous reservoir are summarized. Adopting FMI image log and nuclear magnetic resonance log to quantitative analysis of fractured igneous reservoir and according to formation mechanism and shape of fracture, various fractures are recognized, such as high-angle fracture, low-angle fracture, vertical fracture, reticulated fracture, induced fracture, infilling fracture and corrosion vug. Shang 741 intrusive rock reservoir can be divided into pore-vug compound type, pore fracture type, micro-pore and micro-fracture type. Physical properties parameters of the reservoir are computed and single-well fracture model and reservoir parameters model are established. 6. Various comprehensive methods of fracture prediction and recognition for fractured igneous reservoir are put forward. Adopting three-element (igneous facies, fracture motion and rock bending) geologic comprehensive reservoir evaluation technique and deep-shallow unconventional laterolog constrained inversion technique, lateral prediction of fractured reservoir such as Shang 741 is taken and nonhomogeneity quantification models of reservoirs are established.

山东西部中生代碳酸岩和火山岩的地球化学特征及其成因研究

On account of some very peculiar features, such as extremely high Sr and Nd contents which can buffer their primary isotopic signatures against crustal contamination, deep-seated origin within mantle, and quick ascent in lithosphere, carbonatites are very suitable for deciphering the nature of sub-continental lithospheric mantle(SCLM) and receiving widespread attentions all around the world. The Mesozoic carbonatites located in western Shandong was comprehensively investigated in this dissertation. The extremely high REE concentrations, similar spider diagrams to most other carbonatites around the world and high Sr. low Mn contents of apatite from carbonatites confirm their igneous origin. The K depletion of carbonatites from this studies reflect the co-existing of carbonatite melts with pargasite+phlogopite lherzolite rather than phlogopite lherzolite. Geological characteristics and their occumng without associated silicate rocks argue against their origin of fractionation of or liquid immisibility with carbonated silicate melts. In contrast to the low S7Sr/86Sr and high l43Nd/l44Nd of other carbonatites in the world, carbonatites of this studies show EMU features with high S7Sr/86Sr and low l4jNd/144Nd ratios, which imply that this enriched nature was formed through metasomatism of enriched mantle preexisted beneath the Sino-korean craton by partial melts of subducted middle-lower crust of Yangtze craton. In addition to carbonatites, the coeval Mesozoic volcanic rocks from western Shandong were also studied in this dissertation. Mengyin and Pingyi volcanic rocks, which located in the south parts of western Shandong are shoshonite geochemically. while volcanic rocks cropped out in other places are high-K calc-alkaline series. All these volcanic rocks enriched in LREE and LILE. depleted in HFSE, and show TNT(strong negative anomalies in Ta, Nb. Ti) patterns in spider diagrams which are common phenomena in arc-related volcanic rocks. The Sr-Nd-Pb isotopic systematics reveal that the volcanic rocks decrease gradually in 87Sr/86Sr, 206Pb/204Pb, 20SPb/204Pb and increase in TDM from south to north, suggesting the distinction of SCLM beneath Shandong in Mesozoic is more explicit in south-north trending than in east-west trending. The variable features of SCLM can be attributed to the subduction of Yangtze craton beneath Sino-Korean craton, and subsequent metasomatism of SCLM by partial melts of Yangtze lower crust in different extent.

河北寿王坟铜矿成矿定年及同位素地球化学特征

Samples from carbonate wall-rocks, skarn, ore of skarn type, later calcite vein, and ore of porphyry type in Shouwangfen copper deposit district were collected. Systematic study was carried out on carbon, oxygen, rubidium, strontium and sulfur isotope compositions of carbonates and sulfides in these samples. The first Isochron dating by the Rb-Sr isotopes in chalcopyrite of ore sub-sample was done as well. The following conclusions were obtained. The age (113.6±4.3Ma), obtained by Rb-Sr isotope isochron dating of chalcopyrite and pyrite from sub-sample of skarn ores, probably represents the true mineralization age of skarn ores. That demonstrates the genetic relationship between granodiorite in Shouwangfen complex and skarn copper ores. On the other hand, the Rb-Sr isochron age (73±15Ma) of chalcopyrite from porphyry ores is a little incredible because of bad synthesizing evaluation. But combined with other age data of igneous rocks, it implies the possibility of hydrothermal mineralization in connection with magma activity during the fourth period of Yanshanian in Hebei Province, even in the whole northern edge of Huabei continental block. Together from structure analysis of sulfide sub-samples, from pretreating preccedure of Rb-Sr isotope isochron and its' valuating, we found out that Rb-Sr isotope isochron of sulfide sub-samples is influenced by the crystal structure of sulfides. That is, sulfide ores with very big crystals are not suitable for sub-sample isochron. Carbon, oxygen, sulfur and strontium compositions, of different minerals in these two kinds of ores, imply that the ore-forming hydrothermal fluids were probably derived from magma deep under the crust. The calcite ~(87)Sr/~(86)Sr ratios from the porphyry are consistent to the initial 87Sr/86Sr ratio of the Rb-Sr isochron of chalcopyrite and pyrite in the skarn ore, indicating that these two kinds of ores have the same source characteristic, although the porphyry deposit was formed probably 40 million years later than the skarn one according to our dating results. Skarn and skarn ores are usually considered as interaction product between carbonate wall-rocks and magmatic fluids, but the carbon of the sedimentary carbonate seems not involved in the skarn ores. Considering the connection of magmatic processes and hydrothermal ore formation in the Shouwangfen district, particularly, the spatial distribution of skarn-type and porphyry-type ores, it is possible that the Shouwangfen ore district corresponds to a hydrothermal ore-forming system, which was promoted by high-intruding magmatic rocks. Systematic stable isotopic research can help to reveal the upper part of this hydrothermal ore-forming system, which mainly related to heated and circulating meteoric water, and the lower part principally related to ascending magmatic fluids. Both skarn and porphyry ore-bodies are formed by up-intruding magmatic fluids (even more deep mantle-derived fluids).

西秦岭晚古生代弧前盆地沉积与成矿作用

The Western Qinling Orogenie belt in the Taibai-Fengxian and Xihe-Lixian areas can be subdivided into three units structurally from north to south, which are the island-arc, forearc basin and accretionary wedge, respectively. The forearc basin developed in the Late Paleozoic mainly controls sedimentation and some larger lead-zinc and gold deposits in the western Qinling. Stratigraphically, the island arc is dissected into the Liziyuan Group, the Danfeng Group and the Luohansi Group. The metavolcanic rocks include basic, intermediate and acidic rocks, and their geochemistry demonstrates that these igneous rocks generated in an island arc. Where, the basalts are subalkaline series charactered by low-medium potassium, with enriched LREE, negative Eu anomaly, and positive Nd anomaly. Cr-content of volcanic rocks is 2-3 times higher than that of island arc tholeiite all over the world. In addition, the lightly metamorphosed accretionary wedge in the areas of Huixian, Chengxian, Liuba and Shiqun is dominated by terrigenous sediments with carbonatite, chert, mafic and volcanic rocks. The age of the wedge is the Late Palaeozoic to the Trassic, while previous work suggested that it is the Silurian. The Upper Paleozoic between the island arc belt and accretionary wedge are mainly the sediments filled in the fore arc basin. The fillings in the forearc basin were subdivided into the Dacaiotan Group, the Tieshan Group, the Shujiaba Group and the Xihanshui Group, previously. They outcropped along the southern margins of the Liziyuan Group. The Dacaotan Group, the Upper Devonian, is close to the island arc complex, and composed of a suite of red and gray-green thick and coarse terrestrial elastics. The Shujiaba Group, the Mid-Upper Devonian, is located in the middle of the basin, is mainly fine-grained elastics with a few intercalations of limestone. The Xihanshui Group, which distributes in the southern of the basin, is mainly slates, phyllites and sandstones with carbonatite and reef blocks. The Tieshan Group, the Upper Devonian, just outcrops in the southwest of the basin, is carbonatite and clastic rocks, and deposited in the shallow -sea environment. The faults in the basin are mainly NW trend. The sedimentary characteristics, slump folds, biological assemblages in both sides of and within those faults demonstrate that they were syn-sedimentary faults with multi-period activities. They separated the forearc basin into several sub-basins, which imbricate in the background of a forearc basin with sedimentary characteristics of the piggyback basin. The deep hydrothermal fluid erupted along the syn-sedimentary faults, supported nutrition and energy for the reef, and resulted in hydrothermal-sedimentary rocks, reef and lead-zinc deposits along these faults. The sedimentary facies in the basin varies from the continental slope alluvial fan, to shallow-sea reef facies, and then to deep-water from north to south, which implies that there was a continental slope in the Devonian in the west Qinling. The strata overlap to north and to east respectively. Additionally, the coeval sedimentary facies in north and south are significantly different. The elastics become more and more coarser to north in the basin as well as upward coarsing. These features indicate prograding fillings followed by overlaps of the different fans underwater. The paleocurrent analyses show that the forearc basin is composed of thrust-ramp-basins and deep-water basins. The provenance of the fillings in the basin is the island arc in the north. The lead-zinc deposits were synchronous with the Xihanshui Group in the early stage of development of the forearc basin. They were strongly constrained by syn-sedimentary faults and then modified by the hydrothermal fluids. The gold deposits distributed in the north of the basin resulted from the tectonic activities and magmatism in the later stage of the basin evolution, and occurred at the top of the lead-zinc deposits spatially. The scales of lead-zinc deposits in the south of the basin are larger than that of the gold-deposits. The Pb-Zn deposits in the west of the basin are larger than those in the east, while the Gold deposits in the west of the basin are smaller than those in the east. Mineralizing ages of these deposits become younger and younger to west.

矾山杂岩体成因及其与磷（铁）矿的成矿关系

The Fanshan complex consists of layered potassic ultramafic-syenite intrusions. The Fanshan apatite (-magnetite) deposit occurs in the Fanshan complex, and is an important style of phosphorus deposit in China. The Fanshan complex consists of three (First- to Third-) Phases of intrusion, and then the dikes. The First-Phase Intrusive contains ten typical layered rocks: clinopyroxenite, biotite clinopyroxenite, coarse-grained biotite clinopyroxenite, pegmatitic orthoclase-biotite clinopyroxenite, variegated orthoclase clinopyroxenite, interstitial orthoclase clinopyroxenite, biotite rock, biotite-apatite rock, biotite rock and magnetite-apatite rock. This layered intrusive consists of nine rhythmic units. Each rhythmic unit essentially comprises a pair of layers: clinopyroxenite at the bottom and biotite clinopyroxenite at the top. The apatite (-magnetite) deposit is situated near the top of rhythmic Unit no. 6 of the First-Phase Intrusive. The Second-Phase Intrusive contains three typical rocks: coarse-grained orthoclase clinopyroxenite, . coarse-grained salite syenite and schorlomite-salite syenite. The Third-Phase Intrusive includes pseudo-trachytic salite syenite, porphyritic augite syenite, fine-grained orthoclase clinopyroxenite and fine-grained salite syenite. The origin of the Fanshan complex is always paid attention to it in China. Because most layered igneous intrusion in the world not only have important deposit in it, but also carry many useful information for studying the formation of the intrusion and the evolvement of magma. Two sketch maps were drawn through orebodies along no. 25 cross-cut on 425 mL and no. 1 cross-cut on 491 mL in the Fanshan mine. Through this mapping, a small-scaled rhythmic layering (called sub-rhythmic layering in the present study) was newly found at the top of the rhythmic Unit no. 6. The concept of sub-rhythmic layering is defined in this article. The sub-rhythmic layering is recognized throughout this apatite-rich part, except for magnetite-apatite rock. Presence of the layered magnetite-apatite rock is one of the characteristics of the Fanshan apatite (-magnetite) deposit. Thus, from this layer downwards six units of sub-rhythmic layering are recognized in the present study. Each unit consists of biotite clinopyroxenite (or biotite rock and biotite-apatite rock) layer at the bottom and apatite rock layer at the top. To study this feature in detail is an important work for understanding the origin of the Fanshan complex and apatite (-magnetite) deposit. The origin of the Fanshan complex and the relation of the formation of the apatite(-magnetite)deposit will be interpreted by the study of sub-rhythmic layering on the basis of previous research works. The magma formed the Fanshan complex was rich in K2O, early crystallized pyroxene, and after this phase more biotite crystallized, but no amphibole appeared. This indicated that the activity of H2O in the magma was low. Major element compositions of biotite and clinopyroxene (on thin sections) in the sub-rhythmic layering were analyzed using electron microprobe analyzer. The analytical results indicate Mg/(Mg+Fe*+Mn) atomic ratios (Fe*, total iron) of these two minerals rhythmically changed in sub-rhythmic layering. The trends of Mg/(Mg+Fe*+Mn) atomic ratio (Fe*, total iron) of biotite and clinopyroxene indicate that the magma evolved markedly from relatively magnesian bottom layer to less magnesian top layer in each sub-rhythmic unit. A general trend through the sub-rhythmic layering sequence is both minerals becoming relatively magnesian upwards. The formation temperatures for sub-rhythmic layering yield values between 600 and 800 ℃, were calculated using the ratio of Mg/(Mg+Fe+Mn) in the salite and biotite assemblage. The equilibrium pressures in the rhythmic layers calculated using the contents of Al in the salite were plotted in the section map, shown a concave curve. This indicates that the magma formed the First-Phase Intrusive crystallized by two vis-a-vis ways, from its bottom and top to its centre, and the magnetite-apatite rock was crytallized in the latest stage. The values of equilibrium pressures in the sub-rhythmic layering were 3.6-6.8(xlO8) Pa with calculated using the contents of Al in the salite. The characteristics of geochemistry in various intrusive rocks and the rocks or apatite of sub-rhythmic layers indicated that the Fanshan complex formed by the comagmatic crystallization. The contents of immiscible elements and REEs of apatite rock at the top of one sub-rhythmic unit are more than biotite clinopyroxenite at the bottom. The contents of immiscible elements and REEs of apatite of biotite clinopyroxenite at the bottom of one sub-rhythmic unit are higher than apatite rock at the top. The curves of rocks (or apatite) in the upper sub-rhythmic units are between two curves of the below sub-rhythmic unit in the primitive mantle-normalized trace element abundance spider diagram and the primitive mantle-normalized REE pattern. The trend for the contents of immiscible elements and REEs inclines to the same contents from the bottom to the top in sub-rhythmic layering. These characteristics of geochemistry of rocks or apatites from sub-rhythmic layering indicate that the latter sub-rhythmic unit was produced by the residual magma after crystallization of the previous sub-rhythmic unit. The characteristics of petrology, petrochemistry, geochemistry in the Fanshan complex and sub-rhythmic layers and the trends of Mg/(Mg+Fe+Mn) atomic ratio of biotite and clinopyroxene in sub-rhytmic layering rejected the hypotheses, such as magma immiscibility, ravitational settling and multiple and pulse supplement of magma. The hypothesis of differentiation by crystallization lacks of evidences of field and excludes by this study. On the base of the trends of formation temperatures and pressures, the characteristics of petrology, petrochemistry, geochemistry for the Fanshan complex and the characteristics of geochemistry for the rocks (or apatites), the trends of Mg/(Mg+Fe+Mn) atomic ratio of biotite and clinopyroxene in sub-rhytmic layering, and the data of oxygen, hydrogen, strontium and neodymium isotopes, this study suggests that the magma formed the Fanshan complex was formed by low degree partial melting of mantle at a low activity of H2O, and went through the differentiation at the depth of mantle, then multiply intruded and crystallized. The rhythmic layers of the First-Phase Intrusive formed by the magma fractional crystallized in two vis-a-vis ways, from the bottom and top to the centre in-situ fractional crystallization. The apatite (-magnetite) deposit of the Fanshan complex occurs in sub-rhythmic layering sequence. The the origin of the sub-rhythmic layering is substantially the origin of the Fanshan apatite (-magnetite) deposit. The magma formed the rhythmic layers of First-Phase Intrusive was rich in H2O, F and P at the later stage of its in-situ fractional crystallization. The Fanshan apatite (-magnetite) deposit was formed by this residual magma in-situ fractional crystallization. The magnetite-apatite rock was crystallized by two vis-a-vis ways at the latest stage in-situ fractional crystallization in the rhythmic layers. The result was light apatite layer below heavy the magnetite-apatite layer, formed an "inversion" phenomenon.

安多地区早中侏罗世岩浆岩岩石地球化学和同位素年代学研究及其对构造演化的制约

Anduo area is located in the Central Tibet, the middle segment of the Bangonghu-Nujiang suture. Anduo Block is the northern part of Lhasa terrane. The relationships among the different geological bodies were determined during the 1: 250000 regional geological surveying. Petrography, petrologic geochemistry, isotopic geochemistry and geochronology of igneous rocks from the suture and granitoids from Anduo Block were analyzed systematically as a whole for the first time. Then, their tectonic setting and history are discussed.Anduo ophiolitic melange consists of metamorphic peridotites, cumulates, plagiogranites, sheeted dykes swarm, pillow lava and radiolarian cherts. The concentration of Cr and Ni in the metamorphic peridotites is very high, with Mg# about 0.94 ~ 0.97, higher 87Sr/86Sr and Pb isotopic ratios, and lower 143Nd/i44Nd ratio. LREE is enriched relative to HREE and positive Eu anomaly is very clear. The REE distribution curve is U shape. Nb and Ta anomalies from cumulate gabbro and sheeted dyke swarm are not clear, while that are slightly negative from pillow lava. Plagiogranite belongs to strong calc-alkaline series with high Si, middle Al, low Fe, Mg and low K contents. Eu anomaly (~ 1.23) from plagiogranites is slightly positive. The character of all components of ophiolite is similar to that of the MORB, while to some extent the ophiolite was influenced by crustal material. Anduo ophiolite formed in a mature back-arc basin. Additionally, intermediate acidity volcanic rocks within Anduo phiolite melange are island arc calc-alkline rocks related to ocean subduction.The early-middle Jurassic plutonic rocks are tonalite, granodiorite bearing-phenocryst, magaporphyritic hornblende monzogranite, magaporphyritic monzogranite, monzogranite bearing-phenocryst and syenogranite in turn. They belong to calc-alkaline series which developed from middle K to high K series temporally. REE distribution curves of all plutonic rocks are similar and parallel to each other. SREE and negative Eu anomaly values decrease. In the multi-element spider diagram, the curves of different plutons are similar to each other, but troughs of Nb, Sr, P and Ti from young plutons become more evident. This suggests that thereare some closely petrogenetic affinities among plutonic rocks which make up amagma plutonism cycle of the early-middle Jurassic. Magma source is mainly crustal,but abundant mafic microgranular enclaves within granitoids indicate that crastalmagma should be mixed with mantle-derived magma and the mantle-derived magmadecreased subsequently. Tonalite has features of I-type granite, magaporphyriticmonzogranite is transition type, and monzogranite bearing-phenocryst is S-typegranite. The characteristic of granitoids from Anduo Block suggest that the formingtectonic setting is active continental margin.Reliable zircon U-Pb SHRIMP ages are obtained in the study area firstly. Plagiogranite from the Anduo ophiolite of the Bangonghu-Nujiang suture is 175.1 Ma, and granitoids from Anduo Block is 172.6-185.4 Ma. Additionally, plagioclase from the plagiogranite dates a 40Ar/39Ar age of 144 Ma, while biotite and hornblend from granitoids of Anduo Block give a 163-165 Ma.Similar cooling ages of plagiogranite from the Anduo ophiolitic melange and granitoids from Anduo Block and the spatial distribution of the ophiolitic rocks between Anduo, Naqu, and Shainzha area suggest that bilateral subduction of the Bangonghu-Nujiang oceanic basin took place in the early-middle Jurassic. During this subduction, Anduo ophiolitic rocks were related to north subduction of the Bangonghu-Nujiang oceanic basin and Anduo back-arc basin spreading, while granitoids from Anduo Block were related to south subduction.