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Comment: 14:47 - 15:20 (00:33)
Source: Annenberg/CPB Resources - Earth Revealed - 17. Sedimentary Rocks: The Key to Past Environments
Keywords: "Walter E. Reed", "sedimentary rock", "clastic sediment", "sedimentary structure", "depositional environment", deposition, cross-bedding, river, interruption, progradation
Our transcription: Cross-bedding is a sedimentary structure that's very revealing.
If we look at a set of cross-beds that are very steep, that are truncated by the next set of cross-beds, then we know that we had a river system or a depositional system that was constantly interrupting itself and shifting around.
If we have a smooth progradation of cross-beds, we know there's no interruption, and it's just the steady stream of deposition in more or less a constant fashion.
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