石炭化度のパラメーターに関するいくつかの問題点
1980 年 45 巻 6 号 p. 345-352
詳細
1980 年 45 巻 6 号 p. 345-352
Parameters as coal rank of Eocene to Oligocene coal samples from Kushiro and Ishikari coal fields in Hokkaido were studied. It is shown that the sporinite fluorescence is superior than vitrinite reflectance as coal rank parameter on the basis of volatile matter content and calorific value.
This is based on the fact that chemical and physical properties of vitrinite is liable to be controlled by the difference of plant materials, paleogeography and diagenesis. On the other hand, spores and pollens were scattered without any connection to the location within the sedimentary basin of coal deposition in the limited area (from Kushiro to Ishikari coal fields) and in short geologic time (from Eocene to Oligocene).
In the course of coalification, the variation of distribution on n-alkane occurres at the reflectivity of 0.64-0.71%, the variation of n-alkanes content occurres at reflectivity of 0.63-0.64% and CPI value of different maceral changes over the reflectivity of 0.6%.
It is concluded that the diagenesis stage shifts the catagenesis stage over the reflectance from approximately 0.6-0.65%, this is different from the result of Tissot and Wclte (1978).
