Applied Mechanics and Materials Vol. 733

Abstract: This work uses multiple types of remote sensing data to develop a model-based mineral exploration method. Data used include Worldview-2 satellite data as the main information source supplemented by QuickBird satellite data to assist in geological interpretations and ASTER satellite data to extract remote sensing anomalies. We have enhanced the spectral and spatial resolution of the remote sensing data using ENVI software. Human-computer interaction methods have been used to confirm the geological conditions. We have interpreted 24 distinct lithologic units, including various types of metamorphic and sedimentary rocks. A total of 471 remote sensing anomalies were delineated, consisting of 173 hydroxyl anomalies and 298 iron-staining anomalies. Geological background screening methods were applied to identify 98 remote sensing anomalies, of which 29 were recommended for further study. Based on the interpretation of anomalies extracted from the ASTER and other geological remote sensing data sets, we have established a typical-deposit prospecting model. In the model, we delineated remote sensing prospecting targets by considering: remote sensing anomalies, geologic bodies and structures, geophysical anomalies and geochemical anomalies. Using this model, we divided the work area into two zones based on types of mineral generation. Seven prospecting targets (one A class, three B class and three C class) were identified. Trenching and block sorting methods were conducted for field verification, and resulted in the discovery of two copper and two iron occurrences with commercial potential.

Abstract: In response to the difficulties happened during shale gas horizontal well cementation in shale reservoir of Jiaoshiba Long maxi group in Fuling, through continuous laboratory tests and analysis on site, this paper achieves the following research results: the method of enhancing cleaning efficiency by further improving ahead fluid system; the method of reducing the shrinkage of cement rock and improving anti-gas channeling ability of cement slurry by perfecting the cement slurry system; method of strengthening the supervision of the placement of centralizers by placing the centralizers reasonably; water substitution method with large flow rate of whole well. All these methods form a comprehensive technology, which is applied in 7 wells, such as JY 29-4HF, JY 8-1HF, and JY 15-2HF and so on. All the cement evaluations are great, which indicates that the comprehensive technology is suitable for shale gas horizontal well cementation in Jiaoshiba.

Abstract: In order to analyze the stable organic carbon isotope characteristics and the causes of anthrax lite, 14 samples, containing hydrocarbon source rock, rock and anthrax lite, were selected to test the stable organic carbon and organic nitrogen isotope. Results showed that the relations of stable organic carbon isotope between source rock and anthrax lite were that δ13C source rock <δ13Csmall fault<δ13Clarge fault. Maybe the Early Cambrian anoxic events leaded the hydrocarbon source rock δ13C value low, and different metallogenic evolution and the isotopic fractionation process may be the cause of stable organic carbon isotope value differences between anthrax lite in large and small fault.

Abstract: Metamorphic rock burial hill reservoir of Beier rift in Hailaer Basin, with large scale reservoir and high output has complex fault system. The fault through going direction roughly is NEE direction, and has wide fault section and lateral quickly changed fault displacement. Metamorphic rock reservoir can be divided into the vertical weathered fracture zone, crack and dissolved pores and caves development belt and tight zone. Accumulation is controlled by hydrocarbon ability of source rock, contacting relationship of source rock and reservoir, oil storage ability of reservoir, and vertical and lateral hydrocarbon migration ability of fault and unconformity surface. And formed top surface weathering crust accumulation pattern which the hydrocarbon migrated laterally along the unconformity surface, and interior reservoir pattern of crack broken zone accumulation which hydrocarbon migrated vertically along fault.

Abstract: This paper optimizes the design of the nature of each slug and the combination of slugs through theoretical calculations and laboratory experiments, which is the key to tremendously enhance the oil recovery with the oil-displacing method of multiple multi-slug combinations. When oil-displacing experiments with multiple multi-slug combinations are conducted on heterogeneous cores in the laboratory, it is necessary that each injected slug be designed rationally in their viscosity, volume, etc., with the view to guarantee the synchronous equi-fluidity mobility of each slug after water flooding. With the synergistic effect of a variety of oil-displacing agents, the remaining oil in each permeability layer can be dug, driven by overall piston.

Abstract: Due to the influence of the environment of measurement and complex pore structure in low-permeability reservoir, we use single-well logging data alone to discriminate the degree of reservoir flooded has multiple solutions. In the water flooding procedures, water well and oil well have formed a dynamic developing unit. And with the water propelling, some sand bodies were flooded by water before the well was drilled. The dynamic information of developed wells in connected sand bodies (such as moisture rate and minimum layer water absorption profile, etc.), can reflect the level of water-flooded in some degree. This paper construct the rules of distinguishing the water flooded layer by dynamic analysis data on the basic of dynamic developing unit, which has prolonged the identification accuracy of water flooded layer degree of low-permeability reservoir efficiently.

Abstract: Through the use of conventional inverse Q filtering algorithm can be applied to derive a stable and efficient inverse Q filtering algorithm continuous medium, and through a stable and efficient data validation model inverse Q filtering application results meanwhile summarizes the stable inverse Q filtering characteristics. Finally, the algorithm with a conventional inverse Q filtering were compared, and eventually applied to the actual seismic data.

Abstract: A novel and simple parameterization method using an ensemble of unconditional model realizations is applied to decrease the dimension of the misfit objective function in large-scale history matching problems. The major advantage of this parameterization method is that the singular value decomposition (SVD) calculation is completely avoided, which saves time and cost for huge matrix decomposition and the eigenvectors computations in parameterization process. After objective function transforms from a higher dimension to a lower dimension by parameterization, a Monte Carlo approach is introduced to evaluate the gradient information in the lower domain. Unlike the adjoint-gradient algorithms, the gradient in our method is estimated by Monte Carlo stochastic method, which can be easily coupled with different numerical simulator and avoid complicated adjoint code. When the estimated gradient information is obtained, any gradient-based algorithm can be implemented for optimizing the objective function. The Monte Carlo algorithm combined with the parameterization method is applied to Brugge reservoir field. The result shows that our present method gives a good estimation of reservoir properties and decreases the geological uncertainty without SVD but with a lower final objective function value, which provides a more efficient and useful way for history matching in large scale field.

Abstract: Logging curve processing can effectively eliminate the systematic error of the data and It is the critical initial basic work to improve the precision in reservoir prediction and new hydrocarbon accumulation description while getting a new knowledge of reservoir sand body, Combining with the practical situation of Nanpu structure, the paper optimize logging curve processing methods based on fitting the trend surface. Development of Nanpu 5th tectonic lithology, core porosity, curve correlation coefficient, inversion prediction sandstone and effective sandstone accuracy is obviously increased after applying the technology of well logging curve processing on inversion analysis of East No.1 section the Nanpu 5th structure so as to prove the rationality of the application of trend surface treatment methods of this area, to reduce blindness, and to provides highly consistent logging data to improve development precision.

Abstract: In order to control water and increase oil recovery in reservoir of high temperature (120°C), experiments were carried out to study the impacts of dosage of HPAM, crosslinking agent, delayed crosslinking agent and heat stabilizer on the properties of gel system, and a high temperature-resistant movable weak gel profile control system was presented, whose formula is 2.0g/L HPAM + 0.2% (volume fraction) crosslinking agent + 0.1g/L delayed crosslinking agent + 0.1g/L heat stabilizer. This gel system has good thermal stability at 120°C. It has good flow properties before gelation, and can effectively enter larger pores. After gelation, its viscosity increases so significantly that it can be stranded and the larger pores can be plugged. The plugging rate can be over 93%. Thus, subsequent fluid injection can be redirected into the low-permeability layers, effectively improving the reservoir water absorption profile and oil recovery.