| PDF: | |
| Time: | 2013 |
| Journal: | Acta Petrolei Sinica |
| Volumn: | 34 |
| Issue: | 4 |
| Pages: | |
| Type: | EI |
| Author: | Youfeng Gao,Yanhui Wu,Wanzhu Liu,Xuejiao Qu,Huafeng Tang |
Abstract: | Volcanic intercrystalline micropores mainly formed by recrystallization and dissolution are widely developed in Yingtai fault depression, southern Songliao Basin. According to the origin and types of framework grain, the volcanic intercrystalline micropores can be divided into three types, includes radial alkali feldspar, clay minerals and mixed minerals intercrystalline micropores. Surface porosity analysis shows that, the porosity of centric texture K-feldspar area caused by devitrification is 5.2%, the increment of surface porosity is 9.5%~13.6% where mixed with clay minerals and quartz and feldspar crystallites；the increment of surface porosity is 6.5%~10.1% where feldspar partial dissolution formed illite；The porosity could remind up to 22.3% after the intergranular pore of pyroclastic rocks filled by illite. The exploration survey indicated that volcanic rocks with rich intercrystalline micropores can serve as favorable reservoirs for natural gas. |