摘要
传统的成像测井解释方法对圆柱展开投影中呈正弦形态的火山岩线性裂缝识别较为成熟有效,然而对非线性火山岩岩石构造及复杂岩相几何形态的解释则比较困难。为表征与南美大陆形成相关的古火山复杂环境,本研究基于成像测井、岩相学和地震资料分析,提出了一种新的表征方法。该方法使用全球范围典型火成岩的地质露头照片来创建伪图像,模拟直径约31 cm(12.25 in)井眼的井壁二维平面图像;在此基础上,根据这些伪图像和标准露头照片来确定火成岩结构和岩相的形态模式,并与地下火山和次火山岩地质单元的电缆井眼成像测井图像进行对比,进而为火山岩相的地质评价提供了“可视化标尺”,提升了复杂地质结构的识别效率与可信度。应用该新方法,重点分析了巴西坎波斯、桑托斯和帕纳伊巴等盆地不同尺度的柱状节理和枕状熔岩,并辅以绳状熔岩、熔结凝灰岩、火山碎屑岩和各种侵入特征等实例分析,结果显示,该方法提高了次火山、陆上和水下沉积体解释的准确度。通过成像测井解释结果与区域地质认识相结合,并把古环境研究纳入冈瓦纳大陆裂解相关的裂谷岩浆作用体系研究,对油气勘探开发具有重要意义。
Conventional borehole image log interpretation of linear fractures on volcanic rocks represented as sinusoids on unwrapped cylinder projections is relatively straight-forward,however,interpreting non-linear rock structures and complex facies geometries can be more challenging.To characterize diverse volcanic paleoenvironments related to the formation of the South American continent,this study presents a new methodology based on image logs,petrography,and seismic data.The presented methodology used pseudo-boreholes images generated from outcrop photographs with typical igneous rock features worldwide simulating 2D unwrapped cylinder projections of a 31 cm(12.25 in)diameter well.These synthetic images and standard outcrop photographs were used to define morphological patterns of igneous structures and facies for comparison with wireline borehole image logs from subsurface volcanic and subvolcanic units,providing a“visual scale”for geological evaluation of volcanic facies,significantly enhancing the identification efficiency and reliability of complex geological structures.Our analysis focused on various scales of columnar jointing and pillow lava lobes with additional examples including pahoehoe lava,ignimbrite,hyaloclastite,and various intrusive features in Campos,Santos,and Parnaíba basins in Brazil.This approach increases confidence in the interpretation of subvolcanic,subaerial,and subaqueous deposits.The image log interpretation combined with regional geological knowledge has enabled paleoenvironmental insights into the rift magmatism system related to the breakup of Gondwana with associated implications for hydrocarbon exploration.
作者
FORNERO S A
MILLETT J M
DE JESUS C M
DE LIMA E F
MARINS G M
PEREIRA N F
BEVILAQUA L A
FORNERO S A;MILLETT J M;DE JESUS C M;DE LIMA E F;MARINS G M;PEREIRA N F;BEVILAQUA L A(Petrobras,Rio de Janeiro 20231-030,Brazil;Geosciences Institute,Universidade Federal do Rio Grande do Sul,Campus do Vale,Porto Alegre 91501-970,Brazil;Volcanic Basin Energy Research AS,Oslo N-0361,Norway;Department of Geosciences,Oslo University,Oslo NO-0316,Norway;Centro de Pesquisas e Desenvolvimento Leopoldo Américo Miguez de Mello,Petrobras,Rio de Janeiro 21941-915,Brazil)
出处
《石油勘探与开发》
北大核心
2025年第3期618-637,共20页
Petroleum Exploration and Development
关键词
井眼成像测井
伪图像
火成岩
油气勘探
岩相
测井解释
火山古环境
桑托斯盆地
坎波斯盆地
巴西盆地
borehole image log
pseudo-image
igneous rock
hydrocarbon exploration
lithofacies
log interpretation
volcanic paleoenvironment
Santos Basin
Campos Basin
Brazilian Basin
作者简介
第一作者:FORNERO S A(1982-),女,巴西里约热内卢州人,巴西南里奥格兰德联邦大学在读博士(火山地层学方向研究),巴西国家石油公司高级岩石物理专家,主要从事测井数据处理以及岩石物理研究等工作。地址:Av.Henrique Valadares,28,Centro,CEP 20231-030,Rio de Janeiro,RJ-Brazil。E-mail:fornero@petrobras.com.br。
