JAKARTA, Aug 9 (Reuters) - Indonesia's state oil and gas company, PT Pertamina, will try to restart its 125,000 barrel per day (bpd) Balongan refinery in West Java on Thursday, a senior company official said. Pertamina decided to shut down the refinery after a strong earthquake, measured at a magnitude 7.4, according to the U.S. Geological Survey, rocked the island.