| PDF: | |
| Time: | 2016 |
| Journal: | ACTA PETROLEI SINICA |
| Volumn: | 37 |
| Issue: | 4 |
| Pages: | 454-463 |
| Type: | EI |
| Author: | Ranlei Zhao,Pujun Wang,Hui Zhao,Jian Yi,Taiji Yu,Di Yang,Tan Kong,Huafeng Tang |
Abstract: | Based on cores, thin sections, physical properties, T2 spectrum in nuclear magnetic logging and other data, a research is carried out on the relationship between volcanostratigraphic boundary and reservoir distribution from the aspects of the types and logging identification of volcanostratigraphic boundary in the basin, so as to explore the reservoir control mechanism of volcanostratigraphic boundary. The volcanostratigraphic boundaries of Huoshiling Formation, Wangfu Depression, Southern Songliao Basin are divided into two grades and three types, i.e., the primary boundary consisting of eruptive interval unconformity boundary (EIUB), and the secondary boundary consisting of eruptive conformity boundary (ECB) and eruptive unconformity boundary (EUB). The volcanostratigraphic boundary has a close relationship with reservoirs. The closer to EIUB the reservoir is, the better the physical properties will be, or vice versa. High-quality reservoirs are often developed within 30 m beneath EIUB. Relatively better reservoirs are formed with high physical properties adjacent to ECB and EUB or in the concentrated development zones of such boundaries. The types and distribution of volcanostratigraphic boundary controls the types of reserving space and assemblage relationships, and further influences the reservoir distribution. The reservoir horizons under the control of volcanostratigraphic boundary are divided into three types vertically, i.e., secondary pore zone, primary pore zone and relative tight zone. The EIUB is able to control the development of secondary reserving space to form high-quality reservoirs; ECB and EUB are mainly presented as the concentrated development of primary reserving space to form relatively high-quality reservoirs. Based on the exploration cases in Wangfu Depression, it is suggested that volcanic rock assemblages developed adjacent to volcanostratigraphic boundary, especially at the EUIB, are favorable exploration areas of volcanic hydrocarbons to be focused on. |