The geomechanical behaviour of natural and synthetic gas hydrate bearing sediments

***从天然水合物积累中生产甲烷气体提供了大量环境可持续的非常规天然气，这是一种有前途的未来能源资源。天然气水合物是由氢键结合的水分子组成的结晶化合物，形成一个由包裹的甲烷分子稳定的刚性晶格。这些“冰状”固体在高压和低温下形成；因此，它们被发现在位于北极永久冻土下面的沉积物孔隙空间中，或者在大陆斜坡和边缘的海底下面。***天然气水合物钻探和表征考察中使用的技术最近发生了巨大的变化，其结果是我们对天然气水合物系统的理解发生了巨大的飞跃。由于天然气水合物在常规取心时解离迅速，因此开发了压力取心技术来“锁定”原位静水压力和压力室传递和分析系统，以随后表征未受干扰的沉积物岩心。利用这些系统，最近在今年夏天收集的综合数据集可能会为天然气水合物承载系统提供改变游戏规则的见解。该研究项目考察了这些关于含天然水合物沉积物的新信息与它们合成的实验室类似物之间的联系，进一步加深了我们对这两个系统的理解，最终我们有能力模拟甲烷气生产过程中天然水合物聚集的储层地质力学。***研究方法包括实验室测试、数值模拟和与天然气水合物岩心最新数据的关键比较/分析。通过仔细审查最近在北极和海洋天然气水合物考察中积累的数据集，将建立我们对天然水合物性质知识的新基线。创造力、创新和协作将推动开发高度新颖的实验室工艺，以生产模仿自然样品的合成含水合物样品。重点实验项目旨在定义基本特性和检验中观水平响应，并最终为本构模型提供输入、校准和验证数据。将模拟规模扩大到储层水平，可以探测、理解和预测水合物开采过程中的沉积物响应（储层稳定性、沉降和相关地质灾害）。***天然气水合物是加拿大非常规能源供应的重要组成部分；研究和开发这一前沿天然气符合我们的优先事项，即增加北部开发，行使北极主权，优化能源回收，同时减少经济和环境影响。**

***Production of methane gas from naturally occurring hydrate accumulations offers a vast supply of environmentally sustainable unconventional gas, a promising future energy resource. Gas hydrates are crystalline compounds comprised of hydrogen-bonded water molecules forming a rigid lattice stabilized by encaged methane molecules. These “ice-like” solids form at high pressures and low temperatures; hence they are found within the pore space of sediments located below the permafrost in the Arctic or beneath the seafloor on the continental slopes and margins.***The technology used during gas hydrate drilling and characterization expeditions has recently undergone colossal change, the result of which has been a quantum leap in our understanding of natural gas hydrate systems. Because gas hydrate dissociates rapidly when recovered with conventional coring, pressure-coring techniques were developed to “lock in” the in-situ hydrostatic pressures and pressure chamber transfer and analyses systems built to subsequently characterize the undisturbed sediment core. Utilizing these systems, comprehensive datasets, gathered as recently as this summer, may offer game-changing insights into natural gas hydrate bearing systems. This research program examines the link between this newly available information on natural hydrate bearing sediments and their synthetically constructed laboratory analogs, furthering our understanding of both systems, and ultimately our ability to model reservoir geomechanics in natural hydrate accumulations during methane gas production. ***The research approach involves a combination of laboratory testing, numerical modeling, and critical comparison/analysis with the most up-to-date data from natural gas hydrate core. A new baseline of our knowledge of natural hydrate properties will be established through careful scrutiny of the datasets amassed during recent arctic and marine gas hydrate expeditions. Creativity, innovation, and collaboration will be the instigation for developing highly novel laboratory processes to produce synthetic hydrate-bearing specimens that mimic natural samples. Focused experimental programs aim to define fundamental properties and examine the meso-level response, and to ultimately provide the input, calibration, and verification data for constitutive models. Up scaling to reservoir-level simulations enables probing, understanding, and prediction of the sediment response (reservoir stability, subsidence, and associated geohazards) during gas production from hydrate accumulations.***Gas hydrates are an important component of Canada's unconventional energy supply; research and development of this frontier gas aligns with our priorities to increase northern development, exercise arctic sovereign rights, and optimize energy recovery while reducing economic and environmental impacts. **