新和地区三叠系沉积特征及油气勘探意义

通过对新和地区三叠系岩性组合、沉积构造特征、粒度特征以及地震反射特征等综合研究,确定本区三叠系发育近岸水下扇及深水浊积扇两种类型的砂体。近岸水下扇以灰岩砾、粉砂岩砾以及泥砾组成,浊积扇砂见典型鲍马沉积序列,粒度分析也符合重力流沉积特征,地震反射为孤立存在的透镜状。以此为基础,建立了研究区三叠系近岸水下扇以及深水浊积扇的沉积模式。可见,本区三叠系具有两套可供勘探的目的层,发育多个近岸水下扇和深水浊积扇,并且具备优越的成藏条件,星火3井在两套扇体重均见到油气显示,说明本区三叠系具备良好的勘探潜力。

Sedimentary Characteristics and Significance for the Oil-Gas Exploration in the Triassic Area of Xinhe

Based on the lithologic assemblage, sedimentary structure characteristics, size characteristics andseismic reflection profile in Triassic area of Xinhe , it is showed that the nearshore underwater fan and deep-waterturbidite fan are existent. The nearshore underwater fan is composed of calcareous rock’s grav, siltstone’s gravand boulder clay, while turbidite fan developed Bouma sequence. The size analysis accorded with gravity flow,and the seismic reflection character was insulated and lenticular. The turbidite fan’s depositional models weresummarized in study area of Triassic. Triassic of study area have two exploration targets, it developed a few ofnearshore underwater fan and deep-water turbidite fan, and possessed superior reservoir forming conditions. Andthe indication of oil and gas was detected in XH3 well, which means the two exploration targets of Triassic in thestudy area may be highly prospective for the oil-gas exploration.