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Detailed work recognises a number of ~10 m thick lagerstätten sequences in the formation, each of which formed at a sea-level high stand in deep water.
The lagerstätte were deposited by turbidities and mudslides onto an oxygenated sea floor.

The productive layers comprise mud and clay particles, with a tiny fraction of wind-blown quartz.
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Detailed work recognises a number of ~10 m thick lagerstätten sequences in the formation, each of which formed at a sea-level high stand in deep water. The lagerstätte were deposited by turbidities and mudslides onto an oxygenated sea floor.
The productive layers comprise mud and clay particles, with a tiny fraction of wind-blown quartz.
Wheeler Shale