Abstract: The Es^1L shale oil reservoir in the Raoyang sag,Jizhong Depression,was studied to measure the reservoir rock,crude oil and formation water compressibilities as well as original oil saturation variation with depth,which enable the determination of the variation of the maximum movable oil reserves in massive and laminated shale core samples from diffe-rent burial depth.These shale core samples were analyzed in terms of organic carbon content (TOC),Rock-Eval and porosity according to the well logging plot for the studied horizons.The results show that the movable oil reserves of natural depletion and dissolution gas drive increase with increasing burial depth both in massive and laminated shale reservoirs in Es^1L,except for a sweat spot area located at a burial depth of 2 500 m at the immature production stage.Under natural depletion conditions,the movable oil ratio in massive reservoirs is markedly larger than that in laminated reservoirs,while slightly smaller under solution gas drive conditions.The movable reserves in per unit volume of massive shale oil reservoirs are slightly and obviously smaller than those in laminated shale oil reservoirs under natural depletion and dissolution gas drive respectively.The average movable reserves under natural depletion are 0.13×10^-3 t/m³ and 0.14×10^-3 t/m³,and those under dissolution gas drive are 0.56×10^-3 t/m³ and 1.27×10^-3 t/m³ in massive and laminated shale reservoirs respectively.

Key words: depletion drive, dissolution gas drive, movable oil reserve, shale reservoir, shale oil, Es^1L, Raoyang sag, Bohai Bay Basin