Abstract
Integrated shale gas play evaluation in the structurally complex Southwestern Tarim Basin Piedmont reveals significant resource potential within the Middle Jurassic Yangye Formation. Comprehensive characterization combining geological surveys, core analysis, and advanced geochemical/petrophysical techniques demonstrates moderate-to-high maturity Type II(1) kerogen source rocks with TOC up to 2.68% (average 1.41%), hydrocarbon generation potentials (S(1)+ S(2)) reaching 4.56 mg/g (average 1.77 mg/g), and well-developed mesoporous reservoir systems featuring 1.18-1.47% porosity, 0.00048-0.00178 mD permeability, and > 55% brittle minerals. Microstructural observations reveal that primary intergranular and intragranular pores are the dominant storage spaces. Two distinct accumulation models emerge: (1) monocline-retention type associated with structurally preserved hydrocarbon columns in updip positions; (2) syncline core type linked to overpressured basin centers. Resource estimation yields 1029.51 × 10(8)m(3) in-place gas, supporting exploration targeting in northern monocline structures and deep Jurassic intermontane basins where optimal thermal maturity windows coincide with effective preservation conditions.