测井技术2025，Vol.49Issue(6)：907-916,10.DOI:10.16489/j.issn.1004-1338.2025.06.008
基于岩屑的页岩纳米压痕弹性模量提取新方法及脆性评价研究
Cuttings-Based Nanoindentation Method for Shale Elastic Modulus Extraction and Brittleness Evaluation
摘要
Abstract
To obtain reliable elastic modulus and brittleness parameters for shale under conditions of limited coring and high triaxial-testing costs.This article proposes a multi-source data-fusion workflow for elastic-modulus calculation and brittleness evaluation using drill cuttings as the primary sample material.Mineral composition is determined on cuttings with clear mineralogical textures by scanning electron microscopy with energy-dispersive X-ray spectroscopy.Co-located nanoindentation tests are then performed to measure the microscale elastic moduli of representative minerals,from which a property database for the target interval is compiled.Next,mineral abundances from elemental logging or cuttings X-ray diffraction are combined to estimate equivalent microscale moduli within the Voigt-Reuss-Hill framework.A small set of triaxial tests is used to calibrate the equivalent moduli,and the Voigt upper bound is adopted as the upscaling route to the macroscopic elastic modulus,yielding a continuous modulus profile with depth.Finally,the macroscopic modulus is linearly normalized to obtain a brittleness index.Results indicate that:① The proposed cuttings-based fusion workflow provides reliable elastic-modulus and brittleness estimates under sparse-coring conditions,with depth trends consistent with triaxial tests.② Compared with empirical methods based solely on mineral content,incorporating mineral micromechanical parameters captures within-layer brittleness and heterogeneity effects more faithfully.③ Application in well A and adjacent wells A-1 and A-2 shows that the cross-well fitting determination coefficient is approximately 0.62,and elemental logging and cuttings X-ray diffraction analyses show good agreement in stratigraphic variations and relative amplitudes of key minerals(e.g.,quartz and clays),demonstrating regional transferability and cross-validation potential.④ The workflow is straightforward to implement for rapid field assessment and can be further calibrated with a small amount of local triaxial data.We conclude that the method achieves high accuracy and good adaptability in predicting elastic modulus,providing effective support for mechanical evaluation and hydraulic-fracturing design in shale reservoirs.关键词
岩屑/纳米压痕/弹性模量/元素测井/页岩脆性/X射线衍射Key words
drill cuttings/nanoindentation/elastic modulus/elemental logging/shale brittleness/X-ray diffraction分类
天文与地球科学引用本文复制引用
LI Wei,ZHU Weifeng,SUN Jianmeng,YAO Yibo,XU Lei..基于岩屑的页岩纳米压痕弹性模量提取新方法及脆性评价研究[J].测井技术,2025,49(6):907-916,10.基金项目
国家自然科学基金项目"深部低阻砂岩气藏渗流与导电机理模拟分析研究"(42174143) （42174143）
国家自然科学基金项目"基于数字岩石的深部煤层气弹性和声学响应机理研究"(42474156) （42474156）
