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Matrix-supported rock

In geology, a matrix-supported rock is a sedimentary rock of which a defined majority is the fine-grained matrix as opposed to the clasts or allochems. For a conglomerate, a rock is considered matrix-supported when clasts constitute less than 15% of its volume. Matrix support is considered characteristic of debris flow deposits, in which clasts are supported within a fabric of mud as they move downstream. Wackestones and mudstones under the Dunham classification of limestones are also considered matrix-supported due to the predominance of micrite.

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In geology, a matrix-supported rock is a sedimentary rock of which a defined majority is the fine-grained matrix as opposed to the clasts (in the case of a conglomerate) or allochems (in the case of a limestone). For a conglomerate, a rock is considered matrix-supported when clasts constitute less than 15% of its volume. Matrix support is considered characteristic of debris flow deposits, in which clasts are supported within a fabric of mud as they move downstream.1 Wackestones and mudstones under the Dunham classification of limestones are also considered matrix-supported due to the predominance of micrite (as opposed to, for example, macrofossils).

References

References

  1. Leigh, Sebastian; Hartley, Adrian J. (1992). "Mega-debris flow deposits from the Oligo-Miocene Pindos foreland basin, western mainland Greece: implications for transport mechanisms in ancient deep marine basins". Sedimentology. 39 (6): 1003. Bibcode:1992Sedim..39.1003L. doi:10.1111/j.1365-3091.1992.tb01993.x.