The mud rocks deposited in reducing environment with more saline water, it is better for retention and invert of organic material.

泥岩沉积环境为还原环境，沉积介质咸化程度较高，更有利于有机质的保存和转化。

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By the Gas chromatography and the Gas chromatography-mass spectrogram analysis, the biomarkers in the Lower Cretaceous mud rocks and coals of coal measures from Jixi Basin were studied.

应用气相色谱和色谱—质谱等分析方法，对鸡西盆地下白垩统煤系烃源岩的泥岩和煤岩生物标志物进行研究。

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The rocks left long moving tracks behind in the mud surface.

岩石在泥浆表面留下了长长的移动痕迹。

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He says mud and rocks are blocking some roads, others are torn up, making it difficult to distribute aid.

VOA: standard.2009.10.06

In YouTube videos that have racked up 18 million views, the robotics firm sets its four-legged, 235-pound, deer-size automaton climbing over rocks, slipping on ice and stumbling through mud.

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