The gas which comes from the Carboniferous in the Ordovician reservoirs is found in the eastern part of the field and is associated with the erosive gulleys on the top of the Ordovician.

奥陶系储层的石炭系源气主要分布在气田东部，与奥陶系顶古侵蚀沟关系密切。

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As we approached the mountain, the hills and gulleys bore the appearance of having been created by some vast, fierce torrent rushing around the base of the peak, and tearing its way through the loose earth....

VOA: special.2010.04.26

The Blue Mountains national park is a World Heritage site and covers a million hectares, with huge cliffs, deep rainforest gulleys, sandstone canyons and waterfalls.

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