| PDF: | |
| Time: | 2012 |
| Journal: | Journal of Jilin University(Earth Science Edition) |
| Volumn: | 42 |
| Issue: | 3 |
| Pages: | 583-589 |
| Type: | EI |
| Author: | Huafeng Tang,Pujun Wang,Ruilei Li,Chen Huang,Bing Bai |
Abstract: | Volcanic edifices of Yingcheng Formation and Huoshiling Formation in Songliao Basin were classified into 3 types. They were pyroclastic volcanic edifice, compound volcanic edifice and lava volcanic edifice. According to chemical composition of rocks every type was classified into acid subtype or intermediate -basic subtype. Most volcanic edifices of Yingcheng Formation were acid subtype. The percentage of acid lava volcanic edifice was 33% in northern basin and 38% in southern basin. The proportion of intermediate–basic volcanic edifices in northern basin is more than in southern basin. The volcanic gas pool of Songliao basin was structural-lithologic type. The depth of gas-water interface changed greatly. Internal characteristics of gas pools were controlled by volcanic edifices type. The shape of gas layer of acid pyroclastic volcanic edifice was sill or tabular, and the thickness changed little. The shape of gas layer of acid compound and lava volcanic edifice was mound or sill, and the thickness changed little. The shape of gas layer of intermediate–basic lava volcanic edifice was mound or wedge, and the thickness changed rapidly. The volcanic gas pool forming of Songliao basin was controlled by effective source rocks, faults of communicate source rocks, porosity and permeability. The industrial gas pool of Songliao basin was accumulation in acid lava volcanic edifices, which contribution rate was 50% in northern basin and 38% in southern basin. The efficiency of gas pool formation of intermediate –basic volcanic edifices of northern basin was higher than the southern basin. The acid compound edifices have the maximum productivity of single well. The productivity of acid volcanic edifices was more than the intermediate–basic’s. The volcanic exploration direction was the targets with effective source rocks and faults of communicate source rocks. Firstly, aim the acid volcanic edifice. Secondly, find the intermediate–basic volcanic edifice. |