Extremely High Primary Productivity and Organic Matter Enrichment in Lacustrine Sediments: Late Triassic Chang 7³ Sub-Member, Western Ordos Basin

Figure 3

Photographs of core from Chang 8 to Chang 7³ intervals in well DP1. (a) Dark shale interbedded with fine sandstone in the 1^st to 5^th roundtrips. (b) Gray medium–fine sandstone in the 6^th roundtrip. (c) Fine sandstone in the 2^nd roundtrip. (d) Pyrite nodules in the 4^th roundtrip. (e) Air bubbles occurred in water from the 5^th roundtrip. (F) Yellow crude oil seeped in the 6^th roundtrip. Note that the yellow arrow in (a) indicates the bottom and top of the drilling core.

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