Coal porosity and coal microscopic characteristic for coalbed methane (CBM) analysis of the Warukin Formation in Barito Basin, Idamanggala, Hulu Sungai Selatan, South Kalimantan

Abstract

Research Characteristics of petrology and porosity Coal Formation Warukin, Barito Basin aims to determine the relationship with the permeability of coal coal seam B 11 and A 10. Sampling was conducted at PT Antang Gunung Meratus in Central Warukin Formation coal in seam 11 and 10 by channel sampling. Maceral analysis, vitrinite reflectance and porosity were performed on the above samples. The problem in this research is how the relationship with coal porosity in Warukin Formation low rank to coal methane gas reservoir. Based on the characteristics of the porosity in the coal seam B 11 upper and B 11 lower have a porosity range of 2. 35 to 2.71% while the permeability has a value of 170. 9 – 281.94 mDarcy and on seam coal A 10 upper, A 10 middle, and A 10 lower have porosity 3.05 - 3.99%, permeability of 224.9 – 282.55 mDarcy. Maceral composition consists of vitrinite (desmocolonite and telocolinite) 54.6% - 85%, liptinite (suberinite) 1% - 3%, and inertinite (semifusinite and sclerotinite) 3% - 26.4%. Reflectant virtinite (RV) of the five samples 0.29 -0.35. The strong relationship between the magnitude of porosity and the presence of vitrinite, semifusinte has a strong positive relationship where the greater the value of semifusinite will increase the value of porosity and permiability. Liptinit has a weak and negative relationship. The presence of semifusinite will increase the value of porosity and permeability, this is because the fusinite has pores larger than the other maceral.