辽河坳陷兴隆台潜山中生界地质新认识与油气新发现

New understanding of Mesozoic geology and new discovery of oil and gas in Xinglongtai buried hill, Liaohe depression

为了探究辽河坳陷兴隆台潜山中生界厚层、致密角砾岩的油气勘探潜力及成藏主控因素,指导中生界勘探目标优选,基于岩心、岩屑、测井、地球化学资料,对中生界开展了以储层为核心的地质资料精细重建及油藏主控因素分析。研究结果表明:兴隆台潜山中生界发育两大类30种岩石类型,其中角砾岩分为花岗质角砾岩、混合角砾岩,花岗质角砾岩为最优质储层,储集空间主要为构造缝,其次为溶蚀孔隙;中生界角砾岩油藏为岩性与构造双重控制的层状裂缝型油藏,厚层、均质角砾岩与大断裂叠合区为成藏优势区。利用岩矿、测井、地球化学资料相结合建立岩性及储层识别图版,重建135口开发井的岩性及储层剖面,110口开发井重新解释Ⅰ、Ⅱ类储层。以“老井试油控含油面积、新井钻探定油气产能”的方式对中生界实施效益勘探,10口井全部获工业油气流,兴隆台潜山中生界形成亿吨级规模储量领域,并于2018年上报控制石油地质储量超4000×10^4t。

In order to explore the oil and gas exploration potential and controlling factors of the thick and tight Mesozoic breccia in the Xinglongtai buried hill in Liaohe depression,and guide optimization of Mesozoic exploration targets,fine reconstruction of geological data were carried out and controlling factors were analyzed on the Mesozoic reservoir according to core,debris,well logging and geochemical data.Our study indicates that:(1)30 kinds of rocks in two types are developed in Mesozoic,Xinglongtai buried hill,of which the granitic breccia(the breccias here include granitic breccia and mixed breccia)is the best reservoir with space composed of structural fractures and dissolved pores;(2)the Mesozoic breccia reservoir is a layered fractured reservoir controlled by lithology and structure,and the overlapped zone of thick and homogeneous breccia with large faults is the favorable reservoir zone.After establishing lithology and reservoir identification charts based on the rock minerals,well logging and geochemical data,the lithology and reservoir profiles of 135 development wells were reconstructed,and reservoirs in 110 development wells were reinterpreted into classes I and II.Finally,profitable Mesozoic development was carried out by following the idea"conduct well test to define the controllable oil-bearing areas of old wells,and drill new wells to establish productivity",and 10 wells delivered industrial oil and gas flows.The Mesozoic reservoir in the Xinglongtai buried hill has been proved reserves at 108 ton scale,and in 2018,over 40 million tons of controlled petroleum geological reserves was reported.