The contact metamorphic zone may be further divided into coking coal mixing zone, natural coke zone, coking coal zone and normal coal zone.

接触变质带可进一步划分为岩焦混杂带、天然焦带、焦化煤带、正常煤带。

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The contact metamorphic zone may be further divided into coking coal mixing zone, natural coke zone, coking coal zone and normal coal zone.

接触变质带可进一步划分为岩焦混杂带、天然焦带、焦化煤带、正常煤带。

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