Microstructural Properties of gas hydrates from the Mallik well

Mallik 5L-38天然气水合物研究井是为测试天然气水合物矿床对各种先进开采方法的物理响应而设计的现场实验。同样，它也被用作各种高级日志记录方法的测试。大量证据表明，天然气水合物的微观结构在这两个地区都起着重要的作用。利用低温扫描电子显微镜，我们在一项探索性研究中发现了一些Mallik天然气水合物的亚微米孔隙度，这可能会影响地震响应以及分解动力学。亚微米级的孔隙可能充满了气体，可能是地震反射异常低的所谓“消隐效应”的起因。在这里，我们建议对Mallik气体水合物的亚微米结构进行详细的定量研究。目标将是开发一种亚微米多孔天然气水合物模型，该模型适用于有效的介质建模。基于我们以前的实验室实验，我们还希望通过伴随的拉曼光谱和衍射研究，对成分变化以及目前未知的形成过程有更深入的了解。

The Mallik 5L-38 gas hydrate research well was designed as a field experiment to test the physical response of gas hydrate deposit to various advanced production methods. Likewise it was used as a test for various advanced logging methods. There is accumulated evidence that the microstructure of gas hydrates plays an important role in both areas. Using cryo scanning electron microscopy we have revealed in an exploratory study the sub-micron porosity of some of the Mallik gas hydrates which are likely to affect the seismic response as well as the decomposition kinetics. The sub-micron pores are likely to be filled with gas and may be at the origin of the so-called "blanking effect" with anomalously low seismic reflections. Here we propose a detailed quantitative investigation of the sub-micron structures of Mallik gas hydrates. The goal will be the development a model of sub-micron porous gas hydrates which is suitable for an effective medium modeling. Based on our previous laboratory experiments we also expect some further insight into compositional variations as well as into the presently unknown formation process from accompanying Raman spectroscopy and diffraction studies.