Abstract: Faced with various challenges involved in older, deeper and more complicated oil and gas exploration targets, PetroChina Company Limited (“PetroChina”) vigorously implemented resource strategies and promoted geologic cognition and innovation and engineering technology research during the 12^th Five-Year Plan. New geologic cognitions were innovatively obtained, such as “four-palaeos” (i.e. paleorift, paleo-bioherm beach complex, paleo-trap, and paleo-uplift) controlling the formation of marine carbonate reservoirs, extensive formation of clastics lithologic reservoirs, high-efficient formation of ultra-deep reservoirs in “four-in-one”foreland thrust belts (namely the belts with folded source rock, ultra-deep effective reservoir, very thick gypsum-salt rock, and imbricate structure), and formation of unconventional oil/gas (e.g. shale gas and tight oil) reservoirs. A series of new engineering technologies were developed, including integrated wide-azimuth, broadband and high-density seismic acquisition, processing and interpretation technology, logging evaluation and fluid identification technology for complex reservoirs, safe and fast drilling technology for ultra-deep layers, and horizontal-well volume fracturing technology. During the 12^th Five-Year Plan, 15 large-scale oil and gas reserve zones were discovered, contributing to the performance with proved original oil in place (OOIP) over 6×10⁸t for 10 consecutive years and proved original gas in place (OGIP) over 4000×10⁸m³ for 9 consecutive years. It records the peak period with the longest duration and the highest total production in the history of PetroChina. During the 13^th Five-Year Plan, PetroChina will encounter new situations with changed external environment (e.g. low oil price, and launching of the latest versions of Production Safety Law and Environmental Protection Law) and many internal challenges (e.g. increasing complexity of targets and deterioration of resource quality) in exploration and development. The study indicates that, PetroChina is at the middle stage of exploration and its oil and gas technical innovation is in the period of speeding-up development. During the 13th Five-Year Plan, PetroChina will continue the resource strategies and persist in theoretical, technical and managerial innovation with marine carbonate rocks, tight gas and foreland thrust belts as the key natural gas exploration domains and clastics lithologic formations as the major oil exploration targets. In this way, PetroChina will devote to discover large-scale reserves with high efficiency and quality, in order to increase oil and gas reserves continuously at peak.

Key words: PetroChina, oil and gas exploration, geologic cognition, engineering technology, exploration potential, resource strategy, the 12^th Five-Year Plan, the 13^th Five-Year Plan