Continuous measurements related to gas drainage and cuttings volume at boring were carried out at 20 in-seam boreholes of No.3 slope area in Minami-Oyubari coal mine, which contained the virgin area, influence area due to cross measure boreholes from another rock road, and influence area due to boreholes of previous boring base.
The results obtained were as follows.
1) The relationship between cuttings volume at boring and influence area due to cross measure borings were described.
2) Investigating the relationship between the influence area due to cross measure borings and gas drainage rate, it was recognized that the latter was smaller as the former was larger.
3) It was recognized that cumulative gas drainage volume was in proportion to thepeak value of gas drainage rate.
4) Typical gas drainage curves at each borehole could be divided into two patterns according to geological conditions and gas drainage rates.