Oil production in recent years decreases due to clay migration and the formation of wax and gel asphalt scales.

由于粘土运移及蜡和胶质沥青质垢的生成，近年来油井产量逐年下降。

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So the oil sand's oil is heavy crude oil with high nitrogen, high wax, high gel and low sulfur.

该油砂油是一种高含氮、高含蜡、高含胶、低含硫的重质原油。

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