allochemical rock
Quick Summary
Allochemical rocks are a type of sedimentary rock composed of discrete grains, or "allochems," such as fossil fragments or ooids, along with interstitial matrix and cement. These allochems are transported and deposited as clastic material. Examples of allochems include ooids (spherical calcium carbonate grains), skeletal fragments from marine organisms, and carbonate clasts.1
Carbonate rocks, like limestone and dolomite, are a significant category of nonsiliciclastic sedimentary rocks, primarily formed in marine environments. They are classified based on the types of allochems present and the nature of the pore-filling material, which can be micrite (microcrystalline carbonate mud) or sparite (crystalline carbonate cement). Many important oil reservoirs are found in carbonate rocks.12
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sedimentary rock…clastic sedimentary rocks and (2) allochemical and orthochemical sedimentary rocks.
Read More…clastic sedimentary rocks and (2) allochemical and orthochemical sedimentary rocks.
Read More- sedimentary rockTextural components
…to coarser carbonate grains, or allochems, such as oöids or skeletal fragments, (2) mud-size interstitial calcium carbonate matrix called microcrystalline calcite or micrite, and (3) interlocking, 0.02- to 0.1-millimetre-diameter crystals of clear interstitial calcium carbonate cement or spar. In a rather simplistic sense, these three carbonate rock textural components are…
Read More…to coarser carbonate grains, or allochems, such as oöids or skeletal fragments, (2) mud-size interstitial calcium carbonate matrix called microcrystalline calcite or micrite, and (3) interlocking, 0.02- to 0.1-millimetre-diameter crystals of clear interstitial calcium carbonate cement or spar. In a rather simplistic sense, these three carbonate rock textural components are…
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