| Shanxi fault basin is the main part of the Fen-Wei basins, which is one of the famous seismic, geological disaster areas in the world. Ground fissure as the most serious geological disaster impacts on urban construction and the development of the national economy, and has become the most widely impact and serious geological disasters in Shanxi Province. Research result shows that the formation and development of the ground fissure is mainly controlled by the basement tectonic activity or buried active faults. Therefore, it is one of the key problems to investigate the basin basement tectonic and the distribution of active faults for solving the ground fissure disaster. In present condition, the research on this type of regional tectonic mainly depends on potential field data.In view of above, this thesis relies on the project of"Genetic mechanism of ground-fissure hazards & continental dynamics in Fen-Wei Basin"(Item No.4053021) supported by the National Natural Science Foundation of China, and takes Shanxi fault basin located in the central Shanxi Province as the research area. New technologies are investigated and developed for potential field processing and the tectonic recognition & division are researched for Shanxi fault basin. The main aim is to investigate the deep and shallow tectonic information throughout the region (the distribution of fracture features, the features of formation age paleo-tectonic zone, the characteristics of shallow fault basement tectonic and the features of active faults in the basin). The main raw data are gravity, magnetic potential field data. By means of new methods and technologies to improve the accuracy and the resolution of potential field data processing, binding with deep and shallow seismic sounding profiles, combined with drilling, geological, tectonic evolution, the regional tectonic of Shanxi are studied in-depth. The main research results and conclusions are as follows:1. The multi-resolution wavelet analysis technology is applied into the experimental research of Shanxi potential field data processing for the first time to our knowledge. In contrast to simulation the actual model of the study area data, a semi-quantitative relationship between the order properties of the wavelet decomposition and deep & shallow source structural information has been obtained. Compared with the conventional method, the multi-resolution wavelet analysis technology can not only separate the shallow tectonic information with deep tectonic information remained, but also preserve the details and weak anomalies characteristics of the deep tectonic. During potential field data processing of Shanxi, this technology provides high quality gravity field data information in the deep tectonic researching, which reflects the Moho ups and downs. This technology provides regional aeromagnetic field data formation of age paleo-tectonic zone and shallow (local) gravity field data during shallow basin research, which reflects low-density deposition characteristics of the basin. These results provide a firm basis for further investigations.2. The potential field automatically inversion technology based on the curvature attribute is studied for the first time at home, and innovative improvements are made to the method. After that, it has not only better inversion effect, but also the function of separation different depths field source information. The three main technical measures are as follows: the expanded automatic search maxima method, the multi-resolution threshold method, the combined method of expanded automatic search maxima method and multi-resolution threshold method. Experimental study from model shows that, we can minimize the impact of the noise for the original method, and the result of the inversion is more continuous, the horizontal position and bearing depth are more accurately. At the same time, it has the power distinct the tectonic information from different depths. This method not only enriches the ways of potential field automatically inversion, but also provides another idea for deep and shallow source separation when processing gravity and magnetic anomalies.3. Application the developed technology of potential field automatically inversion technology based on the curvature attribute into Shanxi gravity anomaly data processing, obtained deep and shallow fault information of different depths. Studied the different threshold coefficients k and their corresponding fault information, obtained their semi-quantitative relationship. When the threshold coefficients k =1.0, the obtained Cenozoic era fault system in Shanxi fault basin matches the shallow (local) gravity characteristics obtained by multi-resolution wavelet analysis ,and accesses to the results of the new establishment quaternary tectonic map or the cenozoic group tectonic map, which effective reflects the edge large faults and the limits of faults.4. Investigated new detection techniques of geologic boundaries using potential-field data, the new techniques including tilt derivative (TDR), total horizontal gradient of the TDR and theta map. Model experiment results indicate that the new detection technology is more effective and accurate than the traditional horizontal gradient one and can gather more geological information. Applying those new technologies to the Shanxi gravity anomaly data processing, a wealth of plane fracture information is obtained. Studied the precambrian palaeo-tectonic boundaries detection by using theta map methods to the wavelet decomposition 6-order approximation, combined the geological and the tectonic evolution, and redrawn the precambrian tectonic units. The new redrawn precambrian tectonic units are proved by artificial seismic profiles data. Compared with the previous results, it has much higher resolution and credibility.5. Investigated the magnetic basement tectonic impact to the basin formation by the redrawn Precambrian tectonic units, combined with the artificial seismic profiles data, Studied the relationship between regional tectonic and seismic activity by combining with artificial seismic profiles data, the fault system which detected by gravity and magnetic, and the magnetic crustal tectonic, etc. The results indicated that the formation of fault basin constrained by magnetic crystalline basement. The more complex of the crustal tectonic, the greater the difference mechanical strength between crust media, the smaller thermal water release less, the easier bred major earthquake.6. Mapped the new quaternary tectonic map of four fault basin based on the data of shallow seismic profiles, drilling, and the redrawn fault system divided by the potential data processing, etc. Studied the cenozoic basement tectonic division of the fault basin and the distribution of the active faults in the basement by the new quaternary tectonic map above and the cenozoic tectonic map. The new mapped quaternary tectonic map provides the information of the tectonic division and active fault distribution features. That information can be used to interpret the relationship between ground fissures and buried active faults, which provides important basic information for shallow ground fissures evaluation.The new technologies for potential field processing are investigated and developed as primary means in this thesis, integrated maximize elements of seismic, drilling, geologic, etc. The regional tectonic of Shanxi is researched which provides wealth information for the relying project. It has not only important value for ground fissure disaster prevention and mitigation, but also great significance for mineral resources exploration and evaluation. In addition, the developed new techniques provide new technologies and means for potential field data processing. The work of this thesis has certain academic value and social impact.
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