甘谷驿油田北区三叠系延长组长6油层组沉积微相研究

Sedimentary microfacies in Chang 6 oil-bearing bed of Yanchang formation in the north area of Ganguyi Oilfield

本文利用地质和测井等方法,对甘谷驿油田北区长6油层组沉积体系进行分析。细分出沉积微相,并阐述各小层平面展布特点。该区属三角洲沉积体系,长6油层组细分为分流河道、天然堤、河口坝、远砂坝、水下分流间湾、前缘席状砂、前三角洲几种微相,河道主要呈北东-南西向展布,其中三角洲前缘的水下分流河道是主要油气富积的场所。

Aim Researched into the sedimentary microfacies and the distribution of depositional microfacies of the Chang 6 oil--bearing bed of Yanehang Formation in the north area of Ganguyi Oilfield, to improve a foundation of Palaeogeography for oil--gas. Methods Used geology, physical geology （log） and other techniques , analyze sediment system of Chang 6 oil- bearing bed in study area. Results Fractionize seven types of sedimentary microfaeies, and explain its space distribution characters. Conclusion The agradation in this area belongs to delta sediment system, including the distributary channel , the natural barrier , the distributary mouth bar , the distant sand bar ; the inter--distributary deposits , the front sands sheet and so on . The distributary channel is mostly from north--east to south--west , and the oil--gas is abundant in the distributary channel of the front--delta.