Technological progress and development directions of PetroChina overseas oil and gas field production

MU Longxin,CHEN Yaqiang,XU Anzhu,WANG Ruifeng

Table 1 Development status of overseas oil and gas development technology of PetroChina (modified according to references [1-7]).

Oil and gas domain	Development technology series	Technology connotation and application
Conventional sandstone	Comprehensive remaining oil tapping and development adjustment technology for overseas old sandstone oilfields	Mature technologies of comprehensive remaining oil tapping in domestic old sandstone oilfields are borrowed and applied to overseas marginal oilfields to tap remaining oil and enhance oil recovery.
Conventional sandstone	High speed development technology by natural depletion for overseas sandstone oilfield	The high-speed development model of overseas sandstone oil reservoir is different from that in China. The high-speed development policy must be formulated for overseas sandstone oilfields to realize their high speed and efficient development.
Carbonate reservoir	Overall optimization of development deployment technology for large-scale carbonate reservoir	The development model of the whole injection production pattern of parallel horizontal wells in the thin bioclastic limestone reservoir, the model of injection- production pattern of highly inclined horizontal wells as producer and vertical well as water injector for the huge thick bioclastic limestone reservoir have been created, and the multi-objective collaborative optimization technology of "production rate + investment scale + incremental benefit" has been innovated.
	High efficiency development technology for edge and bottom water carbonate gas field group	The rapid productivity construction technology with highly deviated well for fracture pore type edge and bottom water carbonate gas reservoir and the overall collaborative optimization development technology for gas field group based on the mode of product sharing contract have been innovated.
	Collaborative development technology of gas cap and oil ring for carbonate reservoir with condensate gas cap	The technical policies of collaborative development of gas cap and oil ring under different development modes are made, improving the development effect of oil ring obviously, with the decline of crude oil production slowing down significantly, and the production of gas cap keeping stable at the same time.
Unconven- tional reservoir	Cold recovery technology of foam oil with horizontal well for overall development of ultra-heavy oil reservoir	The mechanism of foam oil displacement has been investigated systematically, the evaluation method of unconventional dissolved gas drive cold production characteristics of foam oil with horizontal well for ultra-heavy oil reservoirs has been innovated, and optimization design technology of horizontal well development for ultra-heavy oil reservoir has been established.
	Key development technology for ultra- high condensate shale gas reservoir	Staged volume fracturing technology in horizontal well has been created for shale gas reservoir, the horizontal sections can reach 1000-2000 m long and fracturing stages can reach up to 22-26.
	Prediction of favorable coalbed methane reservoir and development technology with SIS horizontal wells	High-yield coalbed methane reservoir prediction technology, and development optimization technology of SIS horizontal wells in middle rank coal seam gas field have been established.