渤中34-9油田古近系火山岩岩相特征与分布预测  

Lithofacies characteristics and distribution prediction of Paleogene volcanic rocks in BZ34-9 oilfield

作　　者：尹志军[1] 李超 吕文杰 赵海峰 YIN Zhijun;LI Chao;LYU Wenjie;ZHAO Haifeng(College of Geosciences,China University of Petroleum,Beijing 102249,China;CNOOC China Limited,Tianjin Branch,Tianjin 300459,China)

机构地区：[1]中国石油大学(北京)地球科学学院,北京102249 [2]中海石油(中国)有限公司天津分公司,天津300459

出　　处：《中国海上油气》2020年第5期63-72,共10页China Offshore Oil and Gas

基　　金：“十三五”国家科技重大专项“大型油气田及煤成气开发(编号:2016ZX05047-003)”部分研究成果。

摘　　要：渤中34-9油田是近期渤海海域莱北低凸起围区重要的发现,但多期喷发的火山岩破坏了古近系碎屑岩油藏的完整性,增加了油田开发的难度。综合应用岩心、测井和三维地震资料,从火山岩岩性类型和基本特征入手,采用平剖结合的研究方式,以火山喷发模式为指导,井震联合约束,对渤中34-9油田主力含油层系井间古近系火山岩岩相分布规律进行了精细预测。渤中34-9油田古近系火山岩岩石类型包括玄武岩、安山岩、凝灰岩和火山碎屑沉积岩,按照岩性组合划分出火山通道相、溢流相、爆发相、火山沉积相四种基本火山岩岩相类型。剖面上盾状火山机构互相交叉叠置,火山机构内部火山岩岩相主要表现为单一式、交互式、镶嵌式和孤立式4种叠置样式。在渤中34-9油田古近系主力含油层段中,平面上火山通道相表现出具环状结构的圆形和椭圆形,溢流相呈现明显的南北向朵状和线状定向排列,爆发相和火山沉积相连片分布。火山岩岩相空间分布的预测结果直接应用于油田30余口井的方案优化设计,尤其是平面上识别出的110个火山通道相,为有效规避钻井风险提供了直接的地质依据。The BZ34-9 oilfield is an important discovery achieved recently in the Laibei low bulge enclosed area in the Bohai sea.However,the multi-period eruption of volcanic rocks destroyed the integrity of Paleogene clastic reservoirs,and increased the difficulty in oilfield development.By comprehensively using core,logging and 3 D seismic data,and starting with the lithological types and basic characteristics of volcanic rocks,we have precisely predicted the lithofacies distribution laws of inter-well Paleogene volcanic rocks between the main oil-bearing strata of BZ34-9 oilfield.This prediction was achieved using the study method of planar-profile integration,guided by volcanic eruption models,and constrained by well-seismic combination.The types of Paleogene volcanic rocks in BZ34-9 oilfield include basalt,andesite,tuff and pyroclastic sedimentary rock.Based on the lithological combination,four basic volcanic rock facies can be divided as follows:volcanic channel facies,overflow facies,eruptive facies and volcanic sedimentary facies.On the profile,the shield-shaped volcanic structures are overlapped with each other,and the volcanic rock facies inside the volcanic structures are mainly manifested in four superimposed styles of single,interactive,mosaic and isolated.In the main Paleogene oil-bearing section of BZ34-9 oilfield,the volcanic channel facies appears as a circular or elliptical shape with a ring structure on the plane;the overflow facies appears as the obvious NS-trend directionally arranged lobe and linear bodies,and the eruptive facies is contiguous with the volcanic deposits.The prediction results of the spatial distribution of volcanic rock facies have been directly applied in the optimized design of more than 30 wells in this oilfield,and especially 110 volcanic pathway facies were identified on the plane,which provide a direct geological basis for effectively avoiding drilling risks.

关 键 词：渤中34-9油田 古近系 火山岩岩相 地震相 地震属性 分布预测 

分 类 号：TE122.2[石油与天然气工程—油气勘探]