| dc.description.abstract | After 1999 Chi-Chi earthquake, have many researcher study a lot of topics, but direct measurement the rock of changing of density and porosity of fault-zone rock are very rate. This research is with Taiwan Chelungpu-fault Drilling Project(TCDP) drilling C well of Takung (1050-1280 meters of depth include the drill core that is taken out of area with break of country rock in four major fault-zone ), use the precision type instrument through taking a sample intensively, and consult the experience of A well experiment , and every parameter is taken from with the position altering the sampling method ( bigger and cuts and takes a sample ), in order to reduce the error.
Relieves and appear, the density of rock has obvious changes as the fault change, it is the density that is diminished to the fault centre gradually by the country rock, the porosity becomes great , heat-conductivity is diminished , but the speed of thermal diffusivity becomes large . Thermal-conductivity is average in 2.5W/m/K, increase as the density increases, and the change of the sandstone will be bigger than the shale. The thermal diffusivity is reduced averagely as the density increases, but the sandstone (1.72) is bigger than the shale (1.13).
The heat capacity calculated invites 700 J/kg/K more equally, the sandstone (625) is minimum, and the sandstone and shale (670) take second place, most greatly the shale (820).
The test of density and porosity to have height linear relations (R2 =0.9), And the sample reaches 104, prove this research approach is feasible, it is 2.8g/cm3 that sandstone has density of non-porosity, the sand and shale are 2.84g/cm3, the shale is 2.9g/cm3, the wet density of the whole host rock is in about 2.6 g/cm3. The whole porosity some host rock is under 10, the shale (9.5%) is bigger than the sandstone (7.5%), the characteristic of layer (8.3%) each other of sandstone and shale is between sandstone and shale.
This experiment finds place of 1178.7 meters of depth, there is high porosity up to 40% , and can rub with the hands into easily with the finger directly , the drill core displays too loosely on the appearance before cutting, so rational this fault-zone caused by 921 earthquakes of suspicion. | en_US |