构造煤应力敏感元素迁移聚集规律及构造动力学机制

Although the prediction of coal and gas outburst is the important guarantee for the mine production safety, at present, there is still a lack of effective predictive index system. In the deformation process, both the physical structure and chemical structure of coal show the disciplinary evolution. However, there are still very few studies on the structure - geochemical process of the migration, accumulation and dissipation of chemical elements. In fact, tectonic stress is the main driving force of element migration, therefore, the fruitful achievements of structure-geochemical study on rock deformation can be used for reference. Since coal, as a kind of organic rock, is very sensitive to stress, the dynamic mechanism of element migration in coal deformation process is a new field that deserves great attention and the stress sensitive elements are likely to be extracted to reveal their evolution trends in different stress - strain environments and in different types of tectonically deformed coal, and then they might become an important gas outburst predictive index with indicative value. The aim of this project is to study closely the key scientific problem of " tectonic dynamic mechanism of migrated and accumulation of stress sensitive elements ". By studying the structure evolution mechanism of tectonically deformed coals and deformed coals of high temperature and high pressure experiment, employing extracting and determining the stress sensitive elements as an important technical method, our goal is to establish a coal and gas outburst predictive index system for stress sensitive elements, to study dynamic driving mechanism and geological indication of stress sensitive elements, initially establish research ideas and methods of the interdisciplinary of coal structure-geochemistry.

煤与瓦斯突出预测是矿井安全生产的重要保障，但目前尚缺少有效的预测指标体系。煤在变形过程中，物理和化学结构均表现出规律性的演化，但元素迁移、散失与聚集的构造－地球化学过程研究还十分薄弱。实际上，构造应力是元素迁移的主要驱动力，岩石变形构造-地球化学研究的丰硕成果可供借鉴。煤是一种对应力十分敏感的有机岩石，变形过程中元素迁移的动力学机制是值得关注的新领域，并有可能提炼出应力敏感元素，揭示其在不同应力－应变环境和不同类型构造煤中的演化规律，从而成为具有指示意义的瓦斯突出预测指标。本项目紧密围绕“应力敏感元素迁移聚集的构造动力学机制”这一关键科学问题，通过构造煤及高温高压实验变形煤结构演化机理研究，以提炼和确定应力敏感元素为重要技术方法，以建立煤与瓦斯突出预测的应力敏感元素指标体系为目标，探讨应力敏感元素的动力驱动机制及地质指示作用，初步构建煤构造-地球化学这一交叉学科研究的思路与技术方法。

煤与瓦斯突出预测不仅是国际性的难题，同时也是矿井安全生产的重要保障，而构造煤发育和分布是瓦斯突出预测与评价的关键科学问题。本项目以构造位置独特、构造煤发育普遍且类型较为齐全的安徽宿县矿区为重点研究区域，紧密围绕“构造煤中矿物与元素的动力分异特征与机理”这一关键科学问题，将煤变形构造与地球化学过程密切结合，以“应力敏感元素迁移与聚集的动力学机制”为重点研究内容，以煤变形的高温高压实验为重要技术手段，采用实验变形煤与构造煤综合对比研究的技术方案，在应力敏感元素提炼和确定的基础上，结合构造煤特性研究，揭示了应力敏感元素的动力驱动机制及地质指示作用，初步构建了煤与瓦斯突出预测的应力敏感元素指标体系，为煤与瓦斯突出预测拓展了新的研究领域，并初步形成了煤构造地球化学研究的思路、方法和技术流程。取得的具有创新性的成果主要体现在：揭示了构造煤形成的应力-应变环境，脆、韧性变形转换条件及矿物与元素的响应特征，并从超微观角度揭示了构造煤脆、韧性变形机理；阐释了构造煤动力变质作用中大分子结构演化路径，构建了构造煤大分子结构缺陷发育模式，并从能量角度揭示了构造煤动力变质作用机制；剖析了构造煤中矿物的变形、变位和变质特征及其对元素吸附能力的影响；从微观、显观及宏观三个尺度系统总结构造带内元素的迁移变化规律，揭示了构造煤中矿物和不同类型元素动力分异机制；筛选了应力敏感元素，并将其划分为富集型与散失型两种类型，揭示了构造煤孔隙结构特征与应力敏感元素赋存的内在联系，指出应力敏感元素的迁移富集对构造煤的发育与分布具有指示意义，为煤与瓦斯突出预测提供了新的思路与途径。发表学术论文12篇（其中SCI收录10篇，EI收录2篇），国际会议论文2篇，出版学术专著1部，获得国家发明专利3项。