Major breakthrough of Well Gaotan 1 and exploration prospects of lower assemblage in southern margin of Junggar Basin, NW China

DU Jinhu,ZHI Dongming,LI Jianzhong,YANG Disheng,TANG Yong,QI Xuefeng,XIAO Lixin,WEI Lingyun

Table 2 Physical properties of major reservoirs in the Cretaceous and Jurassic in the southern margin, Junggar Basin.

Profile/well name Fm. Interval/m Lithology Rock density/(g?cm-3) Porosity/% Permeability/10-3 μm2 Tuositai K1q Sandstone, fine sandstone 2.37-2.42 9.00-11.00 2.00-2 000.00 (avg. 67.00) Tuositai J2t Fine sandstone 2.05 23.00 Jiangjungouhe K1q Fine sandstone 2.36 11.90 186.00 Aerqingou anticline K1q Conglomerate-bearing sand- stone, fine sandstone 3.70-14.36 0.14-218.30 (avg. 97.75) Jiergele anticline J2t Fine sandstone, siltstone 2.20 9.00-13.00 5.00-18.00 (max. 69.00) Yixiantian J3k Inequigranular sandstone 16.50 69.00 Qigu anticline J3k Inequigranular sandstone 5.70 0.82 Toutunhe J3k Fine to medium-grained sandstone 16.40 172.00 Fang 2 K1q 4 652.02 Medium to fine-grained sandstone 18.60 256.00 Xihu 1 J2t 6 004.30-6 102.00 Fine sandstone, silty fine sandstone, siltstone 7.32-9.50 0.11-2.27 Dushan 1 J2t 5 844.0 Siltstone 2.43 11.60 0.14 Dafeng 1 J2t 7 154.00-7 280.00 Fine sandstone (cutting) 2.18-2.58 7.30-19.10 Fangcao 1 K1q 5 792.00-5 812.00 Fine sandstone 2.40 16.20 (log interpretation) Gaotan 1 K1q 5 767.50-5 779.00 Silty fine sandstone, conglomerate-bearing fine sandstone 2.36-2.47 13.40-18.40 (log interpretation) Gaotan 1 J2t 5 788.20-5 889.90 Argillaceous siltstone, silty fine sandstone 2.47-2.49 10.30-12.10 (log interpretation)