black shale

noun

Definition of black shale

: a dark form of shale characterized by a relatively high degree of carboniferous compounds The studies of others indicate that major phosphorite deposits are often associated with black shales and accumulated during only a few epochs of geologic history.— D. Z. Pipe et al., Science, 4 Apr. 1975

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First Known Use of black shale

1730, in the meaning defined above

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The first known use of black shale was in 1730

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Cite this Entry

“Black shale.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/black%20shale. Accessed 20 Jan. 2021.

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