Research On Quantitative Evaluation Of Traps Based On Hydrocarbon Pool-forming Simulation

Trap evaluation is a specific and important petroleum resource evaluation work and the work focuses on an accurate assessment of the geological risk. With the development of exploration technology, the underground data can be easier to be gotten and the accuracy of trap evaluation will be improved. However, with the increase in the degree of exploitation of oil and gas, a lot of structural traps have been found because they are obvious and it is difficult to find other traps. The increasing risk of oil and gas exploration is not conducive to the development of the national economy. Petroleum geology researchers recognize the importance of oil and gas exploration in mature exploration areas and exploration of new oil and gas traps in mature exploration areas will be the important content of the oil and gas resource evaluation.In the field of trap evaluation, the majority trap evaluation is directly based on the geological exploration data, the geological evaluation methods can be used for the analysis and prediction of traps. The actual situation of the traps can be directly described by these methods, but the development and changes of the traps can not be dynamically analyzed. The results of the basin and hydrocarbon pool-forming simulation can provide the regional distribution of oil and gas. The basin and hydrocarbon pool-forming simulation can play the role of the zone evaluation. However, the evaluation of traps still needs to be analyzed separately according to the results of the basin and hydrocarbon pool-forming simulation. The current trap evaluation is not based on hydrocarbon pool-forming simulation and the basin simulation data can not be sufficiently utilized. The parameters, model and data need to be reorganized. There is no guarantee about the accuracy and validity of the evaluation. There are many advantages about the comprehensive quantitative evaluation system of traps based on three-dimensional oil and gas accumulation dynamics simulation results. A lot of static parameters can be gotten and the parameters are associated with traps and accumulation conditions. A lot of dynamic parameters about traps and oil and gas reservoir formation and evolution can be gotten. Incompleteness and inconsistency because of the data reorganization can be avoided. The human impact can be reduced and the objectivity of the evaluation can be enhanced. The reliability and accuracy of the evaluation results can be improved.This paper is based on the National Science and Technology Major Project of the Ministry of Science and Technology of China named as large scale oil and gas field and coal gas development, a model engineering of fine evaluation of mature exploration prospect in Dongying Sag of Bohai bay basin. To improve the accuracy and versatility of the trap evaluation method, the research on trap quantitative evaluation models and evaluation methods are the main content and the research are based on hydrocarbon pool-forming simulation. The main work and innovations:1^A quantitative evaluation model of traps based on hydrocarbon pool-forming simulation has been establishedThe traditional trap evaluation is a kind of petroleum geological expert analysis and evaluation based on existing exploration data. The analysis and evaluation of traps based on basin and hydrocarbon pool-forming simulation results can also be done. Traditional ideas of evaluation are unrelated with the hydrocarbon pool-forming simulation or trap evaluation can not closely combine with the hydrocarbon pool-forming simulation and data utilization efficiency is relatively low. Data utilization efficiency can be improved if trap evaluation is based on hydrocarbon pool-forming simulation. The loss of data conversion can be reduced and the extent of data mining can be enhanced. More and reliable information can be provided for the traps quantitative evaluation. The quantitative evaluation of traps based on hydrocarbon pool-forming simulation can not be found from existing articles. The levels of the oil and gas resource evaluation and the key position of trap evaluation and the conventional methods have been explained in the second chapter. The links between the traps quantitative evaluation and oil and hydrocarbon pool-forming simulation have been studied. A quantitative evaluation model of traps based on hydrocarbon pool-forming simulation has been established. The conventional trap evaluation is one kind of evaluation by the experts based on their knowledge of the traps and the detailed exploration data. Subjective evaluation and great risk are the main problem about this kind of evaluation. Quantitative evaluation based on hydrocarbon pool-forming simulation can get the trap data and the result of quantitative evaluation by the data processing and analysis based on the data of hydrocarbon pool-forming simulation. The subjectivity of expert evaluation can be effectively reduced and more objective quantitative evaluation results can be gotten if trap quantitative evaluation is based on the hydrocarbon pool-forming simulation. A quantitative evaluation model of traps based hydrocarbon pool-forming simulation can not be found and the specific model must be established in accordance with the actual situation for the effective evaluation. Quantitative evaluation based on hydrocarbon pool-forming simulation is different with the traditional trap evaluation and the core steps of the model should be implemented. Basin and hydrocarbon pool-forming simulation are the base of the quantitative evaluation of traps. The results of basin and hydrocarbon pool-forming simulation must meet the basic requirements of quantitative evaluation of traps. Trap search and trap information recognition are the base of trap quantitative evaluation and dynamic trap evaluation can be done based on trap search and trap information recognition. Geological evaluation, economic evaluation and comprehensive evaluation can be achieved based on trap search and trap information recognition. The last step is the output and display of the evaluation results. Trap search and trap information recognition are the core steps of quantitative evaluation of traps based on hydrocarbon pool-forming simulation. Quantitative evaluation of traps combined with the hydrocarbon pool-forming simulation are needed to achieve these two steps. Dynamic trap evaluation is the important feature and advantage and the trend of trap dynamic changes can be analyzed. Geological evaluation, economic evaluation and comprehensive evaluation are different with the traditional trap evaluation because data of evaluation is from parameters of trap information recognition.2^Trap search, trap information recognition and dynamic trap evaluation based on corner-point grids have been achievedThe traditional trap evaluation do not need trap search because the experts can get the data of evaluation. Three-dimensional data model is a massive body of data and trap search is a difficult task in the gigantic three-dimensional spatial data. The accuracy and format of the three-dimensional model data are the basic requirements of trap search. The poor model is invalid for the basin and hydrocarbon pool-forming simulation or trap evaluation, but the computer’s performance can not meet the high precision needs. The three-dimensional geological model based on corner-point grids can adapt the irregular geological entity. Trap search is more difficult because comer-point grids are irregular hexahedral. The density of a part of grids should be increased for the high precision and the high density grid should be processed when the trap is searched. Calculation and extraction of the trap information are the key of trap information recognition for many different parameters, different calculation methods and technology requires. Trap condition, oil source condition, storage condition, reservoir condition, matching relation, the accuracy and format of the three-dimensional model data and the position of traps which have been searched are all the basic conditions for calculation and extraction of the trap information. Some parameters can be entered directly bacause some parameters may not be able to get for the limitation of model data. There is no dynamic trap evaluation in Conventional trap evaluation and the development trends of traps can be given by the expert analysis. The geological history of traps can be restored through research and analysis of three-dimensional geological history data. The three-dimensional dynamic display of traps based on the geological history of traps can display the development and changes of traps and the expert can evaluate traps through analysis of traps hydrocarbon accumulation and dissipation.3-. The feedback constraint mechanism of quantitative evaluation of traps to hydrocarbon pool-forming simulation has been ProposedQuantitative evaluation of traps based on hydrocarbon pool-forming simulation is difficult because the limitations of the three-dimensional model and computer performance. Analysis of hydrocarbon pool-forming simulation process is more conducive if the location and parameters of the traps can be determined. Various simulation data can be obtained and a lot of trap data can be extracted because quantitative evaluation of traps is in the end of basin and hydrocarbon pool-forming simulation. The evaluation process can be systematically considered because various simulation data and a lot of trap data can be gotten. There are many micro factors from the three-dimensional geological modeling to tectonic history, thermal history, hydrocarbon generation history, hydrocarbon expulsion history and migration and accumulation history. Simulation process lack systematic and holistic constraints. Rationality of basins and hydrocarbon pool-forming simulation can be analyzed and simulation process can be constrained for the feedback by the analysis of the data of simulation process and the parameters of the traps. The evaluation results will be reasonable and consistent with the geological understanding through multiple feedback simulation. The simulation process can be perfect and the simulation accuracy can be improved. The simulation results of the various stages of basin and hydrocarbon accumulation simulation have a greater impact on the final results of the simulation. Hydrocarbon migration and accumulation simulation is the key of the simulation and has the greatest impact on the final results of the simulation. Requirements of trap evaluation are relatively high to the hydrocarbon migration and accumulation simulation.4-. Characteristics and applicability of geological evaluation methods of traps have been analyzedQuantitative evaluation of traps based on hydrocarbon pool-forming simulation is a new evaluation model. Data sources, evaluation processes and methods are completely different with the traditional trap evaluation. The data source of geological evaluation is the parameters from the trap information recognition and the methods of geological evaluation are the existing methods of quantitative evaluation. As the key of trap evaluation, there are many evaluation methods about geological evaluation of traps, but the effectiveness and applicability are different. As a specific work of petroleum resource evaluation, the characteristics and requirements of geological evaluation of traps are different. In order to get the better effect of trap evaluation, suitable method must be selected before the geological evaluation of traps. The existing geological evaluation methods have been analyzed and compared in the third chapter and these methods are classified according to the data dependence.5、Quantitative evaluation system of traps based on hydrocarbon pool-forming simulation has been achievedQuantitative evaluation of traps based on hydrocarbon pool-forming simulation is a new system theory of evaluation and it is completely different with conventional trap evaluation. The data is mainly from hydrocarbon pool-forming simulation. Trap search, trap information recognition, dynamic trap evaluation, geological evaluation, economic evaluation and comprehensive evaluation are the main stages. The most favorable trap based on the evaluation results can be found and guidance for pre-exploration can be provided. Quantitative evaluation model of traps, system analysis and design and quantitative evaluation system of traps based on hydrocarbon pool-forming simulation has been achieved, according to the theoretical guidance of quantitative evaluation of traps based on hydrocarbon pool-forming simulation. The basic processes and functions have been described. Trap search, trap information recognition, dynamic trap evaluation and geological evaluation of traps are the main content. The positions and ranges of traps must be determined by trap search. The parameters of traps can be extracted and calculated by information recognition on the basis of trap search. Geological history of traps can be restored and the process of trap changes can be dynamically displayed by dynamic trap evaluation. Risk probability, weighted average, fuzzy comprehensive evaluation and artificial neural networks are the geological evaluation methods. These methods are suitable for mature areas of the oil and gas exploration. Each method has its own advantages and shortcomings. More accurate evaluation results can be obtained by the analysis and comparison of the results of the various evaluation methods. Economic evaluation and comprehensive evaluation have been implemented and the final results of evaluation can be gotten.6、The validity of quantitative evaluation system of traps based on hydrocarbon pool-forming simulation has been confirmedNiuzhuang-Wangjiagang region is the mature region of exploration in china. Simulation experiments have been done in Niuzhuang-Wangjiagang. Geothermal evolution, oil and gas generation, emission, migration, accumulation and leakage have been simulated. The comprehensive analysis of simulation results and the proven geological results are consistent. The location of traps and the amount of resources are close to the actual exploration results. Trap boundary and trap type can be accurately obtained. The reliability of the model of quantitative evaluation based on hydrocarbon pool-forming simulation has been verified by the simulation results. The correctness of methods of geological evaluation has also been verified by the simulation resultsA new exploration about the model of quantitative evaluation of traps has been done in this paper and it is also an extension of basin and hydrocarbon pool-forming simulation. This paper has important innovations. A quantitative evaluation model of traps based on hydrocarbon pool-forming simulation has been established. Trap search and trap information recognition based on three-dimensional geological model have been achieved. Trap location and coordinates can be automatically determined. Trap evaluation parameters can be calculated and extracted. Dynamic trap evaluation can be achieved because geological history of traps" can be restored. Three-dimensional dynamic changes of traps can be dynamically displayed. Trap development and changes can be effectively analyzed and the situation of hydrocarbon accumulation and dissipation can be judged. The feedback constraint of hydrocarbon pool-forming simulation has been proposed by data analysis and integration. The rationality of the simulation process has been enhanced and the reliability of the simulation results has been improved.