摘要
综合分析柴达木盆地北缘地区 3 5口井的钻井、测井及岩心资料 ,从沉积角度对该区第三系碎屑岩储集层进行分类及评价。该区储集层以细砂岩和粉砂岩为主 ,主要沉积微相包括冲积扇、河道、三角洲分流河道、滨浅湖滩坝以及泛滥平原砂滩等 ,非均质性很强。根据岩性、沉积相带和物性参数 ,将储集层划分为 3类。物性最好的Ⅰ类储集层是曲流河道和三角洲分支河道的中—细砂岩 ,主要分布在南八仙、马海以及北丘陵等地区 ;物性中等的Ⅱ类储集层岩性为中—粗砂岩和含砾砂岩、砾状砂岩 ,以辫状河道砂体为主 ,包括部分滨浅湖滩坝砂体 ;物性较差的Ⅲ类储集层主要是冲积扇、泛滥平原砂滩、滨浅湖滩坝砂体 ,岩性为砾岩、粉砂岩及泥质粉砂岩。Ⅱ类、Ⅲ类储集层的分布范围比较广泛。图 2表 2参
Drilling, well logging and core data from 35 wells are utilized for reservoir character study of the Tertiary clastic sediments in the north Qaidam Basin, Northwest China. The reservoirs are strongly heterogeneous, mostly fine sands and silts. Their microfacies include alluvial fan, river channel, deltaic distributary channel, and floodplain. Based on lithology, microfacies, and reservoir property, the reservoirs can be classified into three categories. Type Ⅰ medium to fine sands deposited in floodplain meandering channels or deltaic distributary channels. This is the best reservoirs and found mostly in Nanbaxian, Maihai and Beiqiuling area. Type Ⅱ medium to coarse sands, conglomeratic sandstones and pebbly sandstones deposited in braided channels, or occasionally in littoral or marginal lacustrine environments. Reservoir quality of this type is moderate. Type Ⅲ conglomerate, silts or clayey silts deposited at beach, bar, alluvial fan, or floodplain setting. Type Ⅲ is the least desired reservoir type. Type Ⅱ and Ⅲ are the most widely distributed reservoirs in the region.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2003年第4期40-42,共3页
Petroleum Exploration and Development
