Tectonic Control On The Migration And Aggregation Of Trace Elements In Tectonically Deformed Coal In Qidong Coalmine, Huaibei Coalfield

Based on systematic analysis of structural features concerning Qidong coalmine and Huaibei coalfield, tectonically deformed coal(TDC) samples with various deformation types and extents were collected, then the test methods of ICP-MS and CVAFS were used to test the trace elements in TDC of degree deformation in different structure. Trace elements distribution in TDC was discussed with the analysis of stress-strain environment of TDC. Then migration and aggregation Characteristics for tectonically sensitive elements in TDC were analyzed through tectonic geochemistry and tectonic control, final y their dynamic mechanics were revealed. The following conclusions have been made:(1) Structural features and development regularities of Qidong coalmine were analyzed and evaluation of complexity level of faults in No.32 coal seam were made. Faults are developed with NNE and NE. Folds are less developed, however, interlayer-gliding structure are very common in Qidong coalmine. There is a certain regularity in the scope, strike and zoning of mine structure. The small secondary structure plays a dominant role. In Qidong coalmine, the extension of faults has equidistant distribution and the zone with large-medium faults and small secondary faults or the zone with small faults densely developed have a high capacity dimension(2) This paper divided the TDC type systematical y, and preliminarily explored the stress- strain environment of TDC deformation. The TDC was divided into eight categories in Qidong coalmine, such as cataclastic structural coal, mortar structural coal, granulitic structural coal, powder structure coal,schistose structural coal, scaly structural coal, wrinkle structural coal and mylonitic structural coal. The stress-strain environment of TDC deformation and evolution can be divided into extrusion and pull apart fragile fracture deformation environment, shear brittleness or brittle-ductile deformation environment and shear and pull apart ductile deformation environment.(3)The distribution law of trace elements in different TDC were systematical y revealed. We analyzed the distribution characteristics of trace elements in different TDC in NO.32 coal seam, and divided the distribution characteristics into linear increasing type, anti "L" type, "N" type, "M" type and "W" type. The results showed that the migration and aggregation rules of trace elements were related to the deformation degree of TDC.(4)The structure controlling mechanism of migration and aggregation in sensitive element were revealed. Tectonic stress is not only the key factor of TDC deformation, but also is the main driving force for the migration and aggregation of elements in coal. Tectonic stress is a dominant factor, which controls the migration process of stress sensitive element in TDC. Different redox environment which were formed by different structure types, have different influences on the migration and aggregation of elements; TDC in different structure types have different development rules. Its essence is that there are differences in the stressstrain environment when formed the structure and TDC. Structure and the stress-strain environment of its formation is an important factor to cause the differentiation of different stress-sensitive elements.