BEIJING, Dec 14 (Reuters) - China Petroleum and Chemical Corp (600028.SS), known as Sinopec, said on Tuesday it has added 104.88 billion cubic metres (bcm) of newly proven natural gas reserve at the Baima Block in Fuling shale gas field in China"s southwestern Sichuan basin. The new reserve, certified by the Ministry of Natural Resources, drives the field"s total proven reserve to nearly 900 bcm, accounting for 34% of China"s total proven shale gas reserves, Sinopec said in a statement. The highest cumulative gas output of a single well at the Baima Block exceeded 30 million cubic metres, as of end-November, which is at a relatively high level among China"s domestic atmospheric shale gas wells and confirms "a good prospect" for profitable development, the firm said. The Fuling shale gas field has launched 643 wells, churning out more than 41.2 bcm of natural gas. Fuling is China"s first commercially developed large-scale shale gas field.