The rock mass of syenite porphyry in the north part of Babaoshan coal mine was demonstrated on its lithologic characters,geologic age and occurence.

• 从岩体的岩性、时代、产状等方面，论证了八宝山煤矿北部的正长斑岩体为一岩盖，下部找煤前景可观，可在井下实施巷探和定向钻探找煤，以延长矿井寿