According to the nature, Guangxi limestone is separated into three types: pure limestone, siliceous limestone, mixed sand shale or limestone of igneous rock.

广西的石灰岩按性质可分为纯质石灰岩、夹硅质石灰岩、夹砂页岩或火成岩的石灰岩三种类型。

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Applying the stimulation with fracturing for sand shale in Daqing volcanic gas reservoir, the success rate of operation is only 36 percent. The result of the stimulation is bad.

火山岩气藏应用砂泥岩压裂技术进行增产改造，施工成功率只有36%，增产效果差。

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They drill down to the shale, then go sideways and inject high-pressure water, sand or other material into the rock.

当钻到页岩时，从侧面将高压水、沙子和其它东西注入页岩内。

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They drill down to the shale, then go sideways and inject high-pressure water, sand or other material into the rock.

VOA: special.2009.10.23

Rather, as a consequence of injecting water and sand into the shale formation to crack the rocks so gas and oil will flow, massive amounts of waste water comes back to the surface with significant amounts of contaminants as a result of leaching out salt, heavy metals and trace amounts of radioactive materials from the rock formation itself.

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They had been protesting at a site in Hesketh Bank operated by energy firm Cuadrilla which was given a licence in 2008 to extract gas by pumping water, sand and chemicals into shale rock at pressure.

BBC: Hesketh Bank fracking rig protesters guilty of trespass

Under the process of fracking, oil or gas is extracted from shale rock by pumping a mixture of sand, water and chemicals into the rock at high pressure.

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