Then—alkanes with a complete range of carbon number are observed in the saturated hydrocarbons of the bitumen and no evidences of severe biodegradation occur.

这些沥青的饱和烃中正烷烃系列碳数分布完整，没有遭受过严重生物降解作用的迹象。

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Current estimates put the combined bitumen in these deposits at 1.7 trillion barrels, and some geologists believe more field work will jack that number up a fair bit further.

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