摘要
四川盆地的栖霞组主要为灰—灰黑色灰岩及生物碎屑灰岩,沉积相以碳酸盐台内生屑滩相、深和浅缓坡相为主,海水较平静,生物繁茂,富含有机质,具志留系和阳新统2套较好的生油层,生气强度一般>20×108m3/km2,最高达170×108m3/km2,是四川盆地最好的优质生油层。由于灰岩结构以泥晶为主,孔渗差,储气主要靠白云岩化作用、古岩溶作用和裂缝作用,白云岩化作用改善了孔隙空间,古岩溶形成了洞穴(钻具放空量最大可达4.75m),裂缝主要起着孔洞间的连通作用。尽管目前栖霞组的勘探程度尚很低,钻获的气藏较少,但也有高产气井,如自流井气田自2井栖霞组与茅口组合采已累积采气>46.6×108m3,说明潜力不小,前景乐观。
The Qixia Formation of Sichuan Basin is mainly gray-grayish black and bioclastic limestone, and the sedimentary facies are mainly bioclastic bank, and deep and shallow gentle slope in the carbonate platform that had quiet seawater, luxuriant organism, and abundant organic matter. The formation has two better source beds, Silurian system and Yangxing Series, the average gas-generating strength is 〉20 ×10^8m^3/km^2 and the highest attains 170×10^8m^3/km^2 , and they may be the best source beds of Sichuan Basin. As the limestone texture is mainly micritic, porosity and permeability are poor, gas reservation mainly relys on dolomitization, paleokarstification and fracturing. Dolomitization improves the pore space, paleokarst forms caves, in which the tool drilling break may attain 4.75 m, and fractures play the role of connection between pores and caves. Although the exploration degree is very low and the gas reservoir obtained by drilling is fewer, there exists high yield gas producer, such as Well Z1-2 has produced more than 46.6×10^8m^3 of cumulative gas yield from the commingling production of Qixia and Maokou Formations, illustrating a great potential.
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2009年第3期325-334,共10页
Natural Gas Geoscience
关键词
四川盆地
二叠系
栖霞组
天然气
勘探
Sichuan Basin
Permian
Qixia Formation
Natural gas
Exploration.
作者简介
作者电话：028—83310641
