珠江口盆地番禺低隆起A井区珠海组沉积研究

Deposition Characteristics of Zhuhai Formation of Wellblock A in Panyu Low Uplift of Pearl-river Mouth Basin

珠江口盆地番禺低隆起A井区珠海组发育潮汐沉积,以细砂、粉砂和粉砂质泥岩为主,局部含有泥砾。根据A井岩心观察,按岩石学特征出发在珠海组识别出6种岩石相似及3种岩石相组合。据岩相类型和沉积构造特征,可从A井珠海组沉积内识别出3个沉积亚相和3个沉积微相,包括潮下带的潮汐砂坝;潮间带的混合坪微相;三角洲水下平原的水下分流河道。总结出珠海组潮汐影响三角洲的取心段沉积相和沉积演化特征。

Tidal deposits are developed in the area of Zhuhai Formation in Wellblock A in Panyu Low Uplift Zone in Pearl-river Mouth Basin where the fine sands,silty sands and silty mudstone are distributed dominantly and boulder clay are partial visible.On the basis of core observations and descriptions,6 types of lithofacies and 3 types of lithofacies combinations of the Zhuhai Formation can be recognized according to the lithological characteristics.In accordance with lithofacies types and sedimentary structural characteristics,it can be identified into 3 types of depositional sub-facies and 3 types of depositional micro-facies of the tidal deposits in Zhuhai Formation.The subtidal zone including tidal channels and tidal bar,sand and mixed flats and submerged distributary channel.were developed in the intertidal zone.The sedimentary facies of cores and the evolution characteristics of delta deports are summed up in zhuhai formation.