摘要
基于国内外细粒沉积岩岩石类型及定名方案的回顾和总结,分析细粒沉积岩的岩矿特征,并对当前岩石分类及定名中存在的问题进行探讨。在此基础上,沿用三级命名法的原则,从粒级和矿物成分两个角度确定细粒沉积岩岩石分类及定名的新方案:①以粒级(即砂级、粉砂级、泥级)为3端元,将细粒沉积岩划分为泥岩和粉砂岩两大类及12种岩石类型;②以矿物成分(即碳酸盐矿物、长英质碎屑矿物、黏土矿物)为3端元,将细粒沉积岩划分为碳酸盐岩、细粒长英沉积岩、黏土岩及混合细粒沉积岩4大类及18种岩石类型。同时考虑到有机质在非常规油气生成和评价中的重要意义,将其作为第4端元参与定名,并以有机质含量0.5%和2.0%为界,划分出贫有机质、含有机质和富有机质3类。新方案贴近现今非常规油气勘探开发的需求,解决了细粒沉积岩定名中的概念混淆等问题,为细粒沉积学的研究提供了基础术语参考和借鉴。
Based on reviews and summaries of the naming schemes of fine-grained sedimentary rocks,and analysis of characteristics of fine-grained sedimentary rocks,the problems existing in the classification and naming of fine-grained sedimentary rocks are discussed.On this basis,following the principle of three-level nomenclature,a new scheme of rock classification and naming for fine-grained sedimentary rocks is determined from two perspectives:First,fine-grained sedimentary rocks are divided into 12 types in two major categories,mudstone and siltstone,according to particle size(sand,silt and mud).Second,fine-grained sedimentary rocks are divided into 18 types in four categories,carbonate rock,fine-grained felsic sedimentary rock,clay rock and mixed fine-grained sedimentary rock according to mineral composition(carbonate minerals,felsic detrital minerals and clay minerals as three end elements).Considering the importance of organic matter in unconventional oil and gas generation and evaluation,organic matter is taken as the fourth element in the scheme.Taking the organic matter contents of 0.5%and 2%as dividing points,fine grained sedimentary rocks are divided into three categories,organic-poor,organic-bearing,and organic-rich ones.The new scheme meets the requirement of unconventional oil and gas exploration and development today and solves the problem of conceptual confusion in fine-grained sedimentary rocks,providing a unified basic term system for the research of fine-grained sedimentology.
作者
彭军
曾垚
杨一茗
于乐丹
许天宇
PENG Jun;ZENG Yao;YANG Yiming;YU Ledan;XU Tianyu(School of Geoscience and Technology,Southwest Petroleum University,Chengdu 610500,China;Natural Gas Geology Key Laboratory of Sichuan Province,Southwest Petroleum University,Chengdu 610500,China)
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2022年第1期106-115,共10页
Petroleum Exploration and Development
基金
国家自然科学基金面上项目“湖相泥页岩天文地层周期及高分辨率沉积旋回测井研究”(41872166)。
关键词
细粒沉积岩
岩石分类
三级命名法
粒级
矿物成分
fine-grained sedimentary rock
rock classification
three-level nomenclature
particle size
mineral composition
