Sunda盆地(印尼)古近系Zelda段(扇)三角洲沉积特征

前人认为Sunda盆地古近系Talang Akar组Zelda段主要为河流沉.本文通过对岩心的岩性序列与沉积构造、测井曲线形态组合与地震反射特征的系统研究,认为古近系渐新统Zelda段主要为三角洲和扇三角洲沉积体系,在Zelda段沉积早期还发育代表盆地快速下沉阶段的近岸水下扇、滨浅湖、深湖以及浊积扇沉积.详细论述了Zelda段三角洲及扇三角洲的沉积特征和平面分布规律.

Sedimentary characteristics of the (fan) delta of Zelda member (Oligocene) in Sunda Basin, Indonesia

Sunda Basin locates in the north of Sunda strait between Sumatra and Java islands,Indonesia.During early Tertiary,it was a typical half-graben basin and developed a set of terrestrial clastic sedimentation.Previous researchers hold that the early tertiary sedimentations are fluvial depositions.Through the integrated researches of the lithological sequence and depositional structures of cores,the shape of well logging curves and the characteristics of seismic reflection,the authors hold that Zelda member(Oligocene) mainly are deltaic and fan deltaic deposits rather than fluvial deposits.In addition to this,subaqueous fan,coastal shallow lake,deep lake and turbidite fan developed in early stage of Zelda member,which represented the sedimentation during the rapid subsidence of the basin.The sedimentary characteristics and lateral distribution of the deltaic and fan deltaic deposits in the basin are discussed in detail.