摘要
Qilian Mountain permafrost, with area about 10×10^4 km2, locates in the north of Qinghai- Tibet plateau. It equips with perfect conditions and has great prospecting potential for gas hydrate. The Scientific Drilling Project of Gas Hydrate in Qilian Mountain permafrost, which locates in Juhugeng of Muri Coalfield, Tianjun County, Qinghai Province, has been implemented by China Geological Survey in 2008-2009. Four scientific drilling wells have been completed with a total footage of 2059.13 m. Samples of gas hydrate are collected separately from holes DK-1, DK-2 and DK-3. Gas hydrate is hosted under permafrost zone in the 133-396 m interval. The sample is white crystal and easily burning. Anomaly low temperature has been identified by the infrared camera. The gas hydratebearing cores strongly bubble in the water. Gas-bubble and water-drop are emitted from the hydratebearing cores and then characteristic of honeycombed structure is left. The typical spectrum curve of gas hydrate is detected using Raman spectrometry. Furthermore, the logging profile also indicates high electrical resistivity and sonic velocity. Gas hydrate in Qilian Mountain is characterized by a thinner permafrost zone, shallower buried depth, more complex gas component and coal-bed methane origin etc.
Qilian Mountain permafrost, with area about 10×10^4 km2, locates in the north of Qinghai- Tibet plateau. It equips with perfect conditions and has great prospecting potential for gas hydrate. The Scientific Drilling Project of Gas Hydrate in Qilian Mountain permafrost, which locates in Juhugeng of Muri Coalfield, Tianjun County, Qinghai Province, has been implemented by China Geological Survey in 2008-2009. Four scientific drilling wells have been completed with a total footage of 2059.13 m. Samples of gas hydrate are collected separately from holes DK-1, DK-2 and DK-3. Gas hydrate is hosted under permafrost zone in the 133-396 m interval. The sample is white crystal and easily burning. Anomaly low temperature has been identified by the infrared camera. The gas hydratebearing cores strongly bubble in the water. Gas-bubble and water-drop are emitted from the hydratebearing cores and then characteristic of honeycombed structure is left. The typical spectrum curve of gas hydrate is detected using Raman spectrometry. Furthermore, the logging profile also indicates high electrical resistivity and sonic velocity. Gas hydrate in Qilian Mountain is characterized by a thinner permafrost zone, shallower buried depth, more complex gas component and coal-bed methane origin etc.
