The gas of QHD30 1 is mixed gas and mainly from the coal derived gas from pre Tertiary source rocks.

QHD3 0 1气藏的天然气属多源混合气，主气源为前第三系的煤成气。

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A little part is from coal-measures abiogenic gas and from internal abiogenic gas or is known as mantle-derived gas, inorganic matter accounts for21.

少部分来自于煤系地层的无机成因气和深层的无机成因气或者叫幔源气，无机组分在21。

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The coal quality of Xiangxi stage is not good and stable but the coal appears dark mud, well develops shale and has high evolution level, which is favorable to create coal derived gas.

香溪煤系煤质较差，极不稳定，但该煤系暗色泥、页岩发育，演化程度较高，有利于形成煤成气。

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Switching feedstock from naphtha, derived from oil, to ethane, derived from gas, has kept petrochemicals cheap even as oil prices have peaked.

ECONOMIST: Shale gas is giving a big boost to America��s economy

Shale gas derived from sedimentary rocks deep underground needs to be captured, piped and processed before it is consumed.

FORBES: The Other F-Word of Shale Drilling

The reason: Hydrogen engines can run on fuel derived from natural gas more cheaply than other currently available feedstocks.

FORBES: Magazine Article