Skeletal - Halimeda & Recrystalized Reef Rock (B/19/Ple/Eni)
 2.5x
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 2.5x
|
 5x
|
 5x wave plate
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 2.5x
|
 5x
|
| Outstanding feature |
Halimeda in all stages of diagenesis |
| Folk Classification |
Poorly washed halimeda biosparite |
| Dunham Classification |
Halimeda packstone |
| Common Grains |
Halimeda |
| Sorting |
Poor |
| Rounding |
None |
| Micritization & envelopes |
Very thin envelopes on some grains |
| Cement & diagenetic fabric |
Halimeda tubes filled by but also matrex disolving |
| Porosity |
40% intergranular and intragranular |
| Depositional Setting |
Low energy portion of atoll reef |
| Diagenetic history |
Marine and freshwater cementation & disolution |
Halimeda in all stages of diagenesis, from marine cementation within the tubes that penetrate the flakes to disolution of the matrex of the flakes. Note the freshwater equant spar coating some grains, potentially a replacement of an original fibrous aragonite cement.
Thursday, November 11, 2021