东营凹陷幔源流体对原油生物标志化合物的影响研究

A large number of mantle-derived fluid activities occurred in the Dongying Sag. On the basis of the studies on the geochemical characteristics of these fluids in this sag, the spatial distribution of biomarkers in petroleum and their relationships with the parameters of mantle-derived fluids were studied, to reveal the influence of mantle-derived fluids on the biomarkers and to evaluate the reliability of these biomarkers when applied to oil-source correlation and maturity analysis. Most biomarkers used in oil correlation kept the characteristics of their sources during burial thermal evolution. Even some of them were not influenced by mantle derived fluids, such as the relative content of C27-C29 steroid（ααα20R）and C21/C23 tricyclic terpane. However, Pr/Ph and C35/C34 hopanes were sensitive to both heat energy and materiel input by the mantle-derived fluids. γ-waxnae/C30hopanes and C24 tetracyclic terpanes /C26 tricyclic terpanes responded only to thermal influence by mantle-derived fluids. They did not chemically reacted with the mantle-derived fluids. Fluorene series compounds reacted with hydrogen and / or carbon dioxide from the mantle. Mantle-derived fluids affected most maturity index. The huge thermal energy with mantle-devied fluids weakened the relationship between the maturity parameters and depth. Among them, pregnane/C27-29 steroid and Ts/(Ts+Tm) were more sensitive to the heat of the fluids. ααα20S/(20S+20R) took the second place. αββ/(ααα+αββ) and 22S/(22S+22R) were not thermally influenced by the mantle-derived fluid. Besides, the substance of mantle-derived fluids reacted with fragrants, hopanes or moretanoids and thus altered the values of MPI1, MPI2, MPR, C30 hopanes/(C30 hopanes + moretanoids) and alkyl-diben zothiophene/diben zothiophene. The thermal alernation of phenanthrene series and their spatial distribution show that the heat energy carried by mantle-derived fluids was not fierce but spread widely in Dongying Sag, which is favorable to hydrocarbon generation with little destroy. In sum, mantle-derived fluids affected biomarkers through thermal energy and chemical reactions and changed the values of oil-source correlation and maturity parameters in the deep-seated fault belts. Therefore, in the deep-seated fault belts, oil-source correlation should be restudied and the new parameters need to be explored.

鄂尔多斯盆地东部地区奥陶系马家沟组沉积相与储层特征研究

Ordos Basin is one of the primary bases for petroleum exploration in our country. A series of Ordovician large gas fields were discovered, which suggest that the Lower Paleozoic carbonate, especiallly for Ordovician carbonate rocks, preserve plenty of hydrocarbon resources. Well Longtong 1 is studied as the typical exploration well. Acorrding to the specific research on the type of lithology, texture, structure and sedimentary sequence in Ordovician Majiagou Formation as well as additional data from another 20 wells, the sedimentary model has been built in Majiagou Formation. The sedimentary characteristics for each Member in Majiagou Formaiton and the feature of distribution are well understood as below: It suggests that period of Member 1, Member 3 and Member 5 in Majiagou Formation characterize with dry and hot climate as well as drop of the sea level. The area of Well Longtan 1 in the eastern basin is abundant of platform evaporite lithofacies with the depositional anhyrock and salt rock, whereas yield a suite of dolomite intercalated by the thin layers of anhyrock from the anhyrcok-dolomite platform sediment. It deposits muddy dolomite, dolomitic limestone and fine-grain dolomite in limestone-dolomite platform and restricted sea. During the stage of Member 2 and Member 4 in Majiagou Formation, the climate is wet and hot with increasing sea level. The study region occurs limestone with little dolomite in the open sea environment; but the margin area is the restricted sea settings with interbeding dolomite and limestone. Based on the thin section identification, element and isotope analysis as well as the study of texture and structure, it sugguests that the main reserviors are dolomite while the gypsum are major cap rocks. The Member 2 in Majiagou Formation is both the source rocks and the resveroirs; gypsum rocks widely occur in Member 3 as the better cap; similar to the Member 2, the Member 4 in Majiagou Formation is both the source rocks and the resveroirs; there are two source-reservoir-cap assemblages in the Member 5 alone and the cap is gypsum with high quality and great thickness, which is a favorite source-reservoir-cap assemblage.

内蒙古中部道郎和都格铜多金属矿的地质特征矿床类型及找矿模式研究

Daolangheduge copper polymetallic deposit is located on east edge of Ondor Sum-Bainaimiao metallogenic belt, which is a prospective area of porphyry copper deposit, in Xianghuangqi of central Inner Mongolia. Geotectonically, it occurred in the continental margin accretion belt along the north margin of North China Plate, south of the suture zone between North China Plate and Siberian Plate. The intrusive rocks in this area mainly consist of intermediate-acid magmatic rocks, and the quartz veins, tourmaline veins and the transitional phase are comparatively developed. According to our research, the ore-bearing rock body is mainly quartz diorite while the surrounding rock is mainly biotite granite. Besides, the wall rock alteration are mainly propylitization, pyritization and silicification, which consist of epidotization, actinolitization, chloritzation and so on. The metallic minerals are mainly chalcopyrite and pyrite. In addition, the primary ore is mainly of quartz-chalcopyrite-pyrite type. Above all, Daolangheduge copper polymetallic deposit is suggested to be categorized in the porphyry copper type. With isotopic dating and geochemical research on quartz diorite of ore-bearing rock body, the zircon LA-ICP-MS U-Pb dating of two samples yields an age of 266±2 Ma, falling into the range of late Permian Epoch. It is the first accurate age data in Xianghuangqi area, so it should play a key role in the research of deposit and magmatic rocks in this area. With the major elements and trace elements analysis of 14 samples, the quartz diorite should be among the calc-alkaline series, the geochemical characteristics show higher large-ion lithophile elements of Rb, Sr and LREE, low high-field strength elements of Nb, Ta and high transition elements of Cu, Cr . Also, the REE patterns have negative Eu anomalies. With the same analysis of 4 sample for the biotite granite, the geochemical characteristics show higher Rb, Th,, Zr, Hf and LREE, low Nb, Sm and HREE and Eu has no anomaly. It should be among the calc-alkaline series, over aluminum quality and has characteristics of Adakites. According to isotopic dating and geochemical characteristics of ore-bearing rock body, it is suggested that its materials mainly derived from upper mantle that had fractional crystallization and its magma source region may be affected by fluid metasomatism of paleo-asian ocean. It should be an extensional process of post-orogeny according to regional tectonic evolution. Consequently, because of the decrease of temperature and pressure, the ore forming fluid was raised to surface and mineralized accompanied by magmatic activity which might occur in south of the suture zone. By geological survey, further geophysical and geochemical work is needed. In this area, we have accomplished high precision magnetic prospecting, high density electrical survey, gravity prospecting, soil geochemical prospecting, X-ray fluorescence analyzer prospecting and so on. According to geophysical and geochemical abnormal and surface occurrence, 11 drills are arranged to verification. The type of ores are mainly quartz-chalcopyrite-pyrite ores within 3 drills by drill core logging. Although the grade as well as the scale of already-found Cu deposits are insufficient for industrial exploitation, the mineralization prospect in this region is supposed to be great and the potential in mineral exploration at depth is excellent.

隐伏金矿床预测中的地震勘探险方法

Based on brief introduction of seismic exploration and it's general developing situation, the seismic exploration method in field work implementation and some problems frequently encountered in field, which should be pay attention to, are analyzed in detail. The most economic field work techniques are emphasized. Then the seismic data processing flow and it's interpretation technique about the processing results are presented. At last four examples of seismic prospecting in gold deposits are showed. The main conclusions of our research are: 1. Seismic prospecting technique is a very efficient method in the prediction of concealed gold deposits. With appropriate application, it can absolutely reflect the detail underground geological structure in the condition of rugged area and complicated geological environment. 2. The field geometry should be designed and changed according to different kinds of objective exploration depth and ground situation. The best field implementing parameters which include offset, the distance between two adjacent traces, the quantity of dynamite and the depth of hole for explosion, should be determined with examination. Only this way, the high quality original seismic data can be gotten. 3. In seismic data processing, the edition of invalid trace and source gather, signal enhancement, velocity analysis and migration are the key steps. It has some different points with conventional processing and needs a new processing flow and methods which is suitable to the data acquired in rugged area and complicated geological environment. 4. The new common reflection area stacking method in crooked line data processing is an efficient method to improve the signal to noise ratio of seismic data The innovations of our research work are: 1. In the areas which were considered to be forbidden zone, we implement the seismic exploration in several gold deposits in China through our application. All acquire distinguished effects. This show the seismic exploration method is a new effective method in the prediction of concealed gold deposits. 2. We developed a set of seismic field work techniques and data processing which is suitable to complex environment, especially find a effective method in stacking and noise elimination in crooked line data processing. 3. In the field of seismic profile interpretation, through our research work, we are convinced of that: in different kinds of geological condition, the seismic reflection character are not same. For example the lava, the intrusion rock and sediment layers are different in the character of reflection structure and strength. So we accumulate some experience about seismic data interpretation in the area of gold deposits.

准噶尔盆地热历史与油气

Based on the temperature data from 196 wells and thermal conductivity measurements of 90 rock samples, altogether 35 heat flow data are obtained. The results show that the Junggar basin is a relatively "cold basin" at present. The thermal gradients vary between 11.6 and 26.5 ℃/km, and the thermal conductivity change from 0.17 to 3.6 W/mK. Heat flow ranges from 23.4 to 53.7 mW/m~2 with a mean of 42.3 ± 7.7 mW/m~2. The heat flow pattern shows that heat flow is higher on the uplifts and lower on the depressions. The overall low present-day heat flow in the Junggar Basin reflects its stable cratonic basement and Cenozoic tectonothermal evolution characterized by lithospheric thickening, thrust and fault at shallow crust as well as consequently quick subsidence during the Late Cenozoic. The study of the basin thermal history, which is one of the important content of the basin analysis, reveals not only the process of the basin's tectonothermal evolution, but also the thermal evolution of the source rocks based on the hydrocarbon generation models. The latter is very helpful for petroleum exploration. The thermal history of the Junggar basin has been reconstructed through the heat flow based method using the VR and Fission track data. The thermal evolutions of main source rocks (Permian and Jurassic) and the formations of the Permian and the Jurassic petroleum systems as well as the influences of thermal fields to petroleum system also have been discussed in this paper. Thermal history reconstruction derived from vitrinite reflectance data indicates that the Paleozoic formations experienced their maximum paleotemperature during Permian to Triassic with the higher paleoheat flow of around 70-85 mW/m~2 and the basin cooled down to the present low heat flow. The thermal evolution put a quite important effect on the formation and evolution of the petroleum system. The Jurassic petroleum system in the Junggar basin is quite limited in space and the source rocks of Middle-Lower Jurassic entered oli-window only along the foreland region of the North Tianshan belt, where the Jurassic is buried to the depth of 5-7 km. By contrast, the Middle-Lower Permian source rocks have initiated oil and gas generation in latter Permian to Triassic, and the major petroleum systems, like Mahu-West Pen 1 Well, was formed prior to Triassic when later Paleozoic formation reached the maximum paleotemperature.

复杂碎屑岩储层动、静态参数计算理论与方法研究

Reservoir characterization and reservoir modeling are two key techniques in petroleum exploration and development. They all are based on the reliable static and dynamic properties of the reservoirs, especially the static and dynamic properties of the reservoirs at each borehole. Without the static and dynamic properties of the reservoir, reservoir characterization and reservoir modeling will pass into nothingness. In fact, the static and dynamic properties of the reservoir are needed in every domain and stage of petroleum exploration & development Today, petroleum industry has reached a stage worldwide that most of the simple & large massive reservoirs have been well explored and developed. As a result, oil companies are paying more and more attention to the exploration & development of the complex & middle to small clastic reservoirs (such as low resistivity sandstone reservoirs, low or no resistivity contrast sandstone reservoirs, conglomerate reservoirs, volcanoclastic reservoirs). In the recent years, oil companies inside and outside China are focusing on the exploration and development elastic reservoirs. Most of the theories & methods being applicable for simple clastic reservoirs can not be used in complex clasic reservoirs. Some theories & methods that are not resolved in the case of simple clasic reservoirs become more impossible to be resolved in the case of complex elastic reservoirs. A set of theories & methods being applicable for computing the static and dynamic properties of the complex elastic reservoirs are developed in this paper and they have been put into practice successfully. These theories & methods are developed by integrating multi-subjects such as geology, well logging and reservoir engineering, in which geology is used as direction and modern well logging technology is used as basis and reservoir engineering is used as assistance and computer technology is used as tool. There are three outstanding breakthroughs in this paper: of the low porosity fractured and/or vuggy carbonate/igneous reservoirs too. A set of practical theories and methods of computing the static properties (such as porosity, saturation, lithology and fluid type) & dynamic properties (such as permeability and production rate) of simple clastic reservoirs have been developed with the hard efforts of many petroleum engineers and scientists in the past 70 years. However, only some of the theories & methods being applicable for simple clastic reservoirs can be used in complex clastic reservoirs after little modification because of the complexity of the complex clastic reservoirs. Most of the theories & methods being applicable for simple clastic reservoirs can not be used in complex clasic reservoirs. Some theories & methods that are not resolved in the case of simple clasic reservoirs become more impossible to be resolved in the case of complex clastic reservoirs. A set of theories & methods being applicable for computing the static and dynamic properties of the complex clastic reservoirs are developed in this paper and they have been put into practice successfully. These theories & methods are developed by integrating multi-subjects such as geology, well logging and reservoir engineering, in which geology is used as direction and modern well logging technology is used as basis and reservoir engineering is used as assistance and computer technology is used as tool. There are three outstanding breakthroughs in this paper:

松辽盆地南部岩性油藏成藏模式与分布规律

According to the basic geologic conditions, the paper is directed by the modem oil-gas accumulation theory and petroleum system in which typical oil pools are analyzed and the shape of lithologic trap and geologic factors are pointed out. The process during which oil and gas migrate from source rock to lithologic trap is rebuilt, and the accumulation model of oil pool is set up. With the comprehensive application of seismic geologic and log data and paying attention to the method and technology which is used to distinguish lithologic accumulation. Promising structural-lithofacies zones are got and the distribution rule of various lithologic accumulation is concluded. With making use of the biologic mark compound, different reservoirs are compared. As a result, the oil and gas in HeiDimiao come from Nenjiang Group's source rocks; in SaErTu from QingShenkou Group's and Nenjiang Group's, and in PuTaohua. GaoTaizi and FuYang from QingShankou Group's. According to the development and distribution of effective source rock, oil distribution and the comparison in the south of SongLiao basin, the characteristic of basin structure and reservoir distribution is considered, and then the middle-upper reservoir of SongLiao basin south are divided into two petroleum system and a complex petroleum system. Because of the characteristic of migration and accumulation, two petroleum systems can furtherly be divided into 6-7 sub-petroleum systems,20 sub-petroleum systems in all. As a result of the difference of the migration characteristic, accumulation conditions and the place in the petroleum system, the accumulation degree and accumulation model are different. So three accumulation mechanism and six basic accumulation model of lithologic trap are concluded. The distribution of lithologic pools is highly regular oil and gas around the generation sag distribute on favorable structural-lithofacies zones, the type of lithological pool vary regularly from the core of sandstone block to the upper zone. On the basic of regional structure and sedimentary evolution, main factors which control the form of trap are discovered, and it is the critical factor method which is used to discern the lithologic trap. After lots of exploration, 700km~2 potential trap is distinguished and 18391.86 * 10~4 tons geologic reserves is calculated. Oil-water distribution rule of pinch-out oil pool is put up on plane which is the reservoirs can be divided into four sections. This paper presented the law of distribution of oil and water in updip pinch-out reservoir, that is, hydrocarbon-bearing formation in plane can be divided into four zones: bottom edge water zone, underside oil and water zone, middle pure oil zone and above residual water zone. The site of the first well should be assigned to be middle or above pure oil zone, thus the exploration value of this type of reservoir can be recognized correctly. In accordance with the characteristics of seism and geology of low permeability thin sandstone and mudstone alternation layer, the paper applied a set of reservoir prediction technology, that is: (1)seism multi-parameter model identification; (2) using stratum's absorbing and depleting information to predict reservoir's abnormal hydrocarbon-bearing range. With the analysis of the residual resource potential and the research of two petroleum system and the accumulation model, promising objective zones are predicted scientifically. And main exploration aim is the DaRngZi bore in the west of ChangLin basin, and YingTai-SiFangZi middle-upper assembly in Honggang terrace.

胶东蓬家夼式金矿床矿床成因模型与找矿模型研究

The dynamic environments of mineralization in Mesozoic Jiaodong gold mine concentrated area can be devided into two types, compressive environment which related to intracontinental collision and extensional environment which related to intracontinental volcanic rift. The altered rock type (Jiaojia type) and quartz vein type (Linglong type) which related to the former one, were discovered for several years, and became the main types of gold deposits in recent years. A new type gold deposit, syn-detachment altered tectonic breccia type gold deposit, such as Pengjiakuang gold deposit and Songjiagou gold deposit has been discovered on the northeastern margin of Jiaolai Basin. In this paper, the new type of gold deposit has been studied in detail. The study area is located at the northeastern boundaries of Jiaolai Basin, and between the Taocun-Jimo Fault and Wji-Haiyang Fault, in the eastern part of the Jiaodong Block. Pengjiakuang gold deposit and Songjiagou gold deposit occur in a arc-shape detachment fault zone between conglomerate of Lower Cretaceous Laiyang Formation and metamorphic complex of Lower Proterozoic Jingshan Group. Regional geological studies show that Kunyuanshan and Queshan granite intrusions and Qingshanian volcanism were formed in different period of lithospheric thinning of East China in Mesozoic. Granite intrusions were formed in compressive environment, while Qingshanian volcanism were formed in extensional environment. They are all related to the detachment of Sulu Orogenic Belt and the sinistral motion of Tanlu Fault. The Pengjiakuang detachment systems which were formed in the the sinistral motion of Tanlu Fault are the important ore-controlling and ore-containing structure. The Pengjiakuang type gold deposit, controlled by detachment structure, was formed before Yanshanian volcanic period concerning with mixture of meteoric water and magmatic water found in fluid inclusions of gold ores. The minerogenetic epoch has been proposed in 90～120Ma. the host rocks have been extensively subjected to pyritization, silicification, sericitization and carbonatization. Individual ore-body has maximum length of 800m, oblique extension of 500～700m and gold grade of 1～43 * 10~(-6). Native gold is disseminated in silicified, phyllic or carbonatized tectonic breccia. Sulfur, carbon and lead isotope studies on gold ores and wall rocks show that the sulfur come from the metamorphic complex of Lower Proterozoic Jingshan Group, carbon comes from the marble in Jingshan Group, while a part of lead comes from the mantle. The mineralizing fluid is rich in Na~+ and Cl~-, but relatively impoverished in K~+ and F~-. According to the date from hydrogen and oxygen isotopic compositions (δ~(18)OH_2O = 0.59%～4.03%, δDH_2O = -89.5%～97.9%), the conclusion can be reached that the mineralizing fluid of Pengjiakuang gold deposit was a kind of mixed hydrothermal solution which was mainly composed of meteoric water and magmatic water. A genetical model has been formulated. Some apparent anomaly features which show low in the central part and high in the both sides corresponding to the gold-bearing structure, were sum up after analying a vast amount of date by prospecting the orebodies using gamma-ray spectrometer, electrogeochemical parameter technique, controlled source audio magnetic telluric (CSAMT) and shallow surface thermometry in Pengjiakuang gold deposit. The location forecasting problem of buried orebodies has been solved according to these features, and the successful rate is very high in well-drilling. The structural geological-geophysical-geochemical prospecting model has been formulated on the base of the study of geological, geophysical and geochemical characteristics of Pengjiakuang type gold deposit, and the optimum combinational process of geophysical and geochemical prospecting techniques has been summed up. A comparative study shows that the Pengjiakuang type gold deposit, the syn-detachment altered tectonic breccia type gold deposit, is different from Jiaojia type gold deposits and Linglong type gold deposits, in Jiaodong Block. In general, if formed under an extensional tectonic condition and located at detachment fault zone along the margin of Mesozoic Jiaolai basin, and the gold mineralization has also close genetic relationship with alkaline magamtism. Being a new type of gold deposit in Jiaodong gold mine concentrated area, it could be potential to explore in the same regions which processed the same ore-forming geological conditions and mineralization informations.

三角洲储层孔隙结构模型与剩余油分布研究——以临南油田沙河街组储层为例

The study of pore structure in reservoir was paid attention to in the early reservoir research and now a systematic research methodology is set up. On the limits of tools and conditions, methodologies and technologies on formation condition and distribution laws of pore structure and the relationship between remaining oil distribution and pore structure are uncertain and some knownage about it is also uncertain. As the development of petroleum industry, the characterization of pore structure and the prediction of remaining oil are the hot spot and difficult point in the research of oil development. The author pays a close attention to this subject and has done much research on it. In a case study in Linnan oilfield Huimin sag Jiyang Depression Bohai Bay basin by using a new method, named varied scale comprehensive modeling of pore structure, the author builds pore structure models for delta reservoir, reveals the remaining oil distribution laws in delta facies, and predicts the distribution of remaining oil in Linnan oilfield. By the application of stratigraphy, sedimentology and structure geology. the author reveals the genetic types of sandbody and its distribution laws, builds the reservoir geological models for delta sandstone reservoir in Shahejie group in Linnan oilfield and points out the geological Factors that control the development of pores and throats. Combining petrology and the reservoir sensitive analysis, the author builds the rock matrix models. It is the first time to state that rocks in different sentimental micro facies have different sensitive .response to fluid pressed into the rocks. Normally. the reservoirs in the delta front have weaker sensitivity to fluid than the reservoirs in delta plain, In same subfacies, the microfacies that have fine grain, such as bank and crevasse splay, have stronger reservoir sensitivity than the microfacies that have coarse grains, such as under-water branched channel and debauch bar. By the application of advanced testing, such as imagine analysis, scan electronic microscope, and morphology method, the author classifies the pore structure and set up the distribution models of pore, throat and pore structure. By the application of advanced theory in well-logging geology, the author finds the relationship between microscope pore structure and macroscopic percolation characteristics, and then builds the well-logging interpretation formulae for calculating pore structure parameters. By using the geostatistics methods, the author reveals the spatial correlative characteristics of pore structure. By application of conditional stochastic simulation methods, the author builds the 3D models of pore structure in delta reservoir. It is the base of predicting remaining oil distribution. By a great deal of experiments and theoretical deduction, The author expounds the laws of percolation flow in different pore structures, and the laws by which the pore structure controls the micro distribution of remaining oil, and then, states the micro mechanism of remaining oil distribution. There are two types of remaining oil. They are by-pass flow caused by micro-fingering and truncation caused by non-piston movement. By new method, the author states the different pore structure has different replacement efficiency, reveals the formation condition and distribution laws of remaining oil. predicts the remaining oil distribution in Linnan oil field, and put forward some idea about how to adjust the oil production. The study yielded good results in the production in Linnan oilfield.

内蒙古赤峰红花沟地区早中生代构造－岩浆活动特征及金成矿作用

Honghuagou gold field, Inner Mongolia, is selected as the study area for the dissertation. The geological background for gold mineralization, geology of gold deposits, ore-controlling factors, physical and chemical conditions, material sources, genesis and ore-forming epoch for gold mineralization are studied in the dissertation. Especially, the Early Mesozoic tectonic and magmatic activities and their relationship with gold mineralization are studied with special efforts. Based on the study, the criteria for ore-prospecting are systemically summarized, target areas for ore-prospecting are circled and their gold reserves is estimated. Based on the first discovery of Early Mesozoic ductile zone which show the detachment features and the study on the emplacement of Early Mesozoic maficintermediate dyke swarms, the author present that the studied area was mainly in extensional uplift state during Early Mesozoic. The tectonic evolution can be divided into two stages. The extension was dominated by ductile metamorphose at early stage, whose geodynamics was related with the post orogenic extension after the collision between the Northern China Plate with Siberia Plate. The extension at late stage was featured by the intrusion of diorite and the emplacement of dyke swarms, whose geodynamics was related with mantle uplift. The gold deposits in the area are just the products of the tectonic and magmatic activities resulted from Early Mesozoic extension. The plagio-amphibolite from Archean metamorphic rocks is partially melted under the influence of underplating caused by mantle uplift, result in the formation of diorite magma. The gold in metamorphic rocks will also be melted into magma pond, and ascend into the upper parts of crust along with the intrusion of magma. The gold-bearing hydrothermal fluids is formed during magma differentiation, and caused the precipitation and concentration of gold in favorable geological conditions, result in the formation of gold deposits. The fracture caused by the emplacement of dyke swarms break a path for the ascending and movement of hydrothermal fluids, some of them become parts of ore-controlling and host structure. The gold is thought to be formed in Early Mesozoic, not in Yanshanian epoch.

塔里木盆地轮南地区三叠系油气地质模型及油气预测研究

As an important measure to understand oil and gas accumulation during petroleum exploration and development, Petroleum geological model is an integrated system of theories and methods, which includes sedimentology, reservoir geology, structural geology, petroleum geology and other geological theories, and is used to describe or predict the distribution of oil and gas. Progressive exploration and development for oil and gas is commonly used in terrestrial sedimentary basin in China for the oil and gas generation, accumulation and exploitation are very intricate. It is necessary to establish petroleum geological model, adaptive to different periods of progressive exploration and development practice. Meanwhile there is lack of an integrated system of theories and methods of petroleum geological model suitable for different exploration and development stages for oil and gas, because the current different models are intercrossed, which emphasize their different aspects. According to the characteristics of exploration and development for the Triassic oil and gas pool in Lunnan area, Tarim Basin, the Lunnan horst belt was selected as the major study object of this paper. On the basis of the study of petroleum geological model system, the petroleum geological models for different exploration and development stages are established, which could be applied to predict the distribution of oil and gas distribution. The main results are as follows. (1) The generation-accumulation and exploration-development of hydrocarbon are taken as an integrated system during the course of time, so petroleum exploration and development are closely combined. Under the guidance of some philosophical views that the whole world could be understood, the present writer realizes that any one kind of petroleum geological models can be used to predict and guide petroleum exploration and development practice. The writer do not recognize that any one kind of petroleum geological models can be viewed as sole model for guiding the petroleum exploration and development in the world. Based on the differences of extents and details of research work during various stage of exploration and development for oil and gas, the system of classification for petroleum geological models is established, which can be regarded as theoretical basis for progressive petroleum exploration and development. (2) A petroleum geological model was established based on detailed researches on the Triassic stratigraphy, structure, sedimentology and reservoir rocks in the Lunnan area, northern Tarim Basin. Some sub-belt of hydrocarbon accumulation in the Lunnan area are divided and the predominate controlling factors for oil and gas distribution in the Lunnan area are given out. (3) Geological models for Lunnan and Jiefangqudong oil fields were rebuilt by the combinations of seismology and geology, exploration and development, dynamic and static behavior, thus finding out the distribution of potential zones for oil and gas accumulations. Meanwhile Oil and gas accumulations were considered as the important unit in progressive exploration and development, and the classification was made for Lunnan Triassic pools. Petroleum geological model was created through 3D seismic fine interpretation and detailed description of characteristics of reservoir rocks and the distribution of oil and gas, especially for LN3 and LN26 well zones. The possible distribution of Triassic oil traps and their efficiency in the Lunnan area has been forecasted, and quantitative analysis for original oil(water) saturation in oil pools was performed. (4) The concept of oil cell is proposed by the writer for the first time. It represents the relatively oil-rich zones in oil pool, which were formed by the differences of fluid flows during the middle stage of reservoir development. The classification of oil cells is also given out in this paper. After the studies of physical and numerical modeling, the dominant controlling factors for the formation of various oil cells are analyzed. Oil cells are considered as the most important hydrocarbon potential zones after first recovery, which are main object of progressive development adjustment and improvement oil recovery. An example as main target of analysis was made for various oil cells of Triassic reservoir in the LN2 well area. (5) It is important and necessary that the classification of flow unit and the establishment of geological model of flow unit based on analysis of forecast for inter-well reservoir parameters connected with the statistical analysis of reservoir character of horizontal wells. With the help of self-adaptive interpolation and stochastic simulation, the geological model of flow units was built on the basis of division and correlation of flow units, with which the residual oil distribution in TIII reservoir in the LN2 well area after water flooding can be established.

柴达木盆地北缘地区油气成藏过程模拟与含油气系统评价

As an important part of petroleum exploration areas in the west of China, the north part of Qaidam basin is very promising in making great progress for petroleum discovery. But there are still many obstacles to overcome in understanding the process of petroleum formation and evaluation of oil & gas potential because of the complexity of geological evolution in the study area. Based upon the petroleum system theory, the process of petroleum formation is analyzed and the potential of oil & gas is evaluated in different petroleum systems by means of the modeling approach. The geological background for the formation of petroleum systems and the consisting elements of petroleum systems are described in detail. The thickness of strata eroded is estimated by means of vitrinite reflectance modeling, compaction parameter calculating and thickness extrapolating. The buried histories are reconstructed using the transient compaction model, which combines of forward and reverse modeling. The geo-history evolution consists of four stages - sedimentation in different rates with different areas and slow subsidence during Jurassic, uplifting and erosion during Cretaceous, fast subsidence during the early and middle periods of Tertiary, subsidence and uplifting in alternation during the late period of Tertiary and Quaternary. The thermal gradients in the study area are from 2.0 ℃/100m to 2.6 ℃/100m, and the average of heat flow is 50.6 mW/m~2. From the vitrinite reflectance and apatite fission track data, a new approach based up Adaptive Genetic Algorithms for thermal history reconstruction is presented and used to estimate the plaeo-heat flow. The results of modeling show that the heat flow decreased and the basin got cooler from Jurassic to now. Oil generation from kerogens, gas generation from kerogens and gas cracked from oil are modeled by kinetic models. The kinetic parameters are calculated from the data obtained from laboratory experiments. The evolution of source rock maturation is modeled by means of Easy %Ro method. With the reconstruction of geo-histories and thermal histories and hydrocarbon generation, the oil and gas generation intensities for lower and middle Jurassic source rocks in different time are calculated. The results suggest that the source rocks got into maturation during the time of Xiaganchaigou sedimentation. The oil & gas generation centers for lower Jurassic source rocks locate in Yikeyawuru sag, Kunteyi sag and Eboliang area. The centers of generation for middle Jurassic source rocks locate in Saishenteng faulted sag and Yuka faulted sag. With the evidence of bio-markers and isotopes of carbonates, the oil or gas in Lenghusihao, Lenghuwuhao, Nanbaxian and Mahai oilfields is from lower Jurassic source rocks, and the oil or gas in Yuka is from middle Jurassic source rocks. Based up the results of the modeling, the distribution of source rocks and occurrence of oil and gas, there should be two petroleum systems in the study area. The key moments for these two petroleum, J_1-R(!) and J_2-J_3, are at the stages of Xiaganchaigou-Shangyoushashan sedimentation and Xiayoushashan-Shizigou sedimentation. With the kinetic midels for oil generated from kerogen, gas generated from kerogen and oil cracked to gas, the amount of oil and gas generated at different time in the two petroleum systems is calculated. The cumulative amount of oil generated from kerogen, gas generated from kerogen and gas cracked from oil is 409.78 * 10~8t, 360518.40 * 10~8m~3, and 186.50 * 10~8t in J_1-R(!). The amount of oil and gas generated for accumulation is 223.28 * 10~8t and 606692.99 * 10~8m~3 in J_1-R(!). The cumulative amount of oil generated from kerogen, gas generated from kerogen and gas cracked from oil is 29.05 * 10~8t, 23025.29 * 10~8m~3 and 14.42 * 10~8t in J_2-J_3 (!). The amount of oil and gas generated for accumulation is 14.63 * 10~8t and 42055.44 * 10~8m~3 in J_2-J_3 (!). The total oil and gas potential is 9.52 * 10~8t and 1946.25 * 10~8m~3.

流体地球化学：成因、流动和流体-岩石相互作用及塔里木盆地实例研究

Geofluid in sedimentary basins is related to petroleum generation, migration, accumulation and preservation, and is a topic of geological frontier. By integrating the multi-discipline methods of petroleum geochemistry, sedimentology, hydrogeology, petroleum geology and experimental geochemistry, the thesis has carried out experiments of microcline dissolution in solutions with organic acids, crude oil, brines with high total dissolved solids (TDS), and has dealt with Al distribution between the crude oil and the brines after the experiments. Cases for study includes Central Tarim, Hetianhe Gas Field and Kucha forland basin with data containing fluid chemistry and isotopic compositions, thin sections of sandstones and carbonates, homogenization temperatures and salinities of fluid inclusions, isotopic compositions of bulk rock and autigenic minerals. The aims are to elucidate fluid origin and flow in the three areas, effect of hydrocarbon emplacement on diagenesis, and to show occurrence of microbe-mediated, and thermochemical sulfate reduction in the Tarim Basin. Microcline dissolution experiments show that after 100 hour, part of the dissolved Al distributes in the crude oil, and the Al concentrations in the crude oil rise when organic acids are added. The result can be used to explain that most oilfield waters in the Tarim Basin are characterized by less than 3mg/L Al. Crude oil added to the solutions can enhance microcline dissolution, which is also observed in the case - Silurian sandstones with early crude oil emplacement in the Central Tarim. Al and Si have higher concentrations in the experiments of oxalic acid than of acetic acid under the same pH conditions, suggesting that there exist Al-oxalate and Si-oxalate complexes. Presence of acetate can enhance the activity of Ca and Al, but Al concentrations have not been increased significantly due to formation of small Al-acetate complex during the experiments. Relationships between δD and δ~(18)O in conjunction with chemistry of oilfield waters show that the waters are evaporated connate waters, which subsequently mixed with meteoric water, and were influenced by water-rock interactions such as salt dissolution, dolomitization of calcite, albitization of feldspar. In the Hetianhe Gas Field where salt dissolution took place, δD and δ~(18)O values can be used to trace nicely meteoric water recharge area and flow direction, but TDS can not. Part of the waters have high TDS but very light δD and δ~(18)O. When combined with paleo-topography, or fluid potentials, meteoric water is suggested to flow eastward in the Hetianhe Gas Field, which is the same with the Central Tarim. Whist in the Kuche forland basin, meteoric water may have permeated Cambrian-Ordovician strata. Relationship between ~(87)Sr/~(86)Sr and 1/Sr can be used to indicate migration and mixing of brines from carbonate strata (low ~(87)Sr/~(86)Sr ratio but high Sr content), clastic strata (high ~(87)Sr/~(86)Sr ratio but low Sr content) and crystalline basement (high ~(87)Sr/~(86)Sr ratio and heavy δ~(18)O value). Using this approach, it can be found that ~(87)Sr-depleted brine from Ordovician carbonates have migrated up to and mixed with ~(87)Sr-enriched waters from Silurian and Carboniferous sandstones, and that Silurian brines have mixed with meteoric water. In the Kuche forland basin, brines from the Cambrian and Ordovician carbonates have higher ~(87)Sr/~(86)Sr ratios than those from the overlying sandstones, when combined with chemistry, δ~(15)N and ~3He/~4He ratios of the coexisting natural gases, suggesting that the brines were derived from the basement. There exists some debate on the effect of hydrocarbon emplacement on mineral diagenesis. Case-study from Silurian sandstones in the Central Tarim show that quartz has kept overgrowing secondarily when oil saturation was decreased by meteoric water flushing subsequently to hydrocarbon emplacement. Silicon precipitates on the water-wet quartz surface, leading to decreased Si concentration close to the surface. A Si grads can result in Si diffusion, which supplies Si for quartz overgrowth. Hydrocarbon oxidation-sulfate reduction is an important type of organic-inorganic interaction. Not only can it make secondary alteration of hydrocarbons, but generate H_2S and CO_2 gases which can improve reservoir property. Thermochemical sulfate reduction took place at the temperatures more than 125 ℃ to 140 ℃ in the Cambrian-Ordovician carbonates, the products - H_2S and CO_2 gases migrated up to the Silurian, and precipitated as pyrite and calcite, respectively. The pyrite has an average δ~(34)S value close to those of Ordovician seawater and anhydrite, and calcite has δ~(13)C value as low as -21.5‰. In the Hetianhe Gas Field, sulfate reduction bacteria carried by meteoric water flowing eastward may have preferentially depleted ~(12)C of light hydrocarbon gases, and results in heavier δ~(13)C values of the residual hydrocarbon gases and higher molar CO_2 in the natural gases in the west than in the east. Coexisting pyrite has δ~(34)S values as low as -24.9‰.

岩石热开裂的实验研究

Micro-cracks appeared between the boundaries of different minerals of rocks during heating process, because of different thermal expansion coefficients of minerals, this phenomenon is referred as thermal cracking of rocks. The transport property of rocks was changed greatly due to the thermal cracking induced micro-cracks network, for example, the permeability of carbonate increases about 10 times when the temperature arise from room temperature to 110～120℃. Thermal cracking of rocks is a new research field of rock physics, which related closely to rock mechanics, mineralogy as well as experimental technology. The thermal cracking experiments of various rocks were performed, the rock macroscopic properties such as porosity, permeability, velocities of elastic waves in rocks were obtained as a function of temperature of heating process, and the microscopic structures of rocks were observed by using Scanning Electro-Microscope (SEM). The mechanism and the theoretical model of thermal cracking of rocks are given at present paper. Finally, the potential implication of rock thermal cracking to petroleum industry is discussed.

扩散波勘探方法基础及其在石油油气藏开发中的应用研究

As we know, the essence of exploration is objective body determined by getting the information. Such as seismic、electrical and electromagnetic prospecting, they are the common methods of the exploration. Therefore, They have a complete set of theory now. In fact, the effective information can also be got by the diffusion way, it is called diffusion prospecting. The diffusion way prospecting is necessary and important. The way of diffusion prospecting is studied in the paper and main works include below: (1) On the basis of studying basic law of the diffusion, the paper gives the idea of diffusion wave and the formulas of computing diffusion wave function. (2) The paper studies the way of the diffusion prospecting and the methods of data processing. At the same time, it also expounds the characteristics and the applied foreground of the diffusion prospecting. (3) The paper gives the tomography idea and the basic method of diffusion CT. Meanwhile, it also expounds the foreground that the diffusion CT is applied in oil development prospecting. (4) As the inversion of the diffusion equation is a part of the diffusion prospecting way, the methods of diffusion equation inversion are studied and the two formulas are deduced --Laplace transform and polynomial fitting inversion formulas. As the other important result of diffusion equation inversion, the inversion can offer a new analysis method for well Testing in oil development. In order to show a set of methods in the paper feasible, forward、inversion and CT numerical simulation are done in the paper.