Grapestones & Echinoid with overgrowths (Int/9)
10x
|
2.5x
|
5x
|
5x
|
2.5 cross nicols
|
2.5 wave plate
|
5x wave plate
|
Outstanding feature |
Grapestones & echinoids with overgrowths calcite spar cement |
Folk Classification |
Skeletal bimodal poorly washed intrasparite |
Dunham Classification |
Skeletal bimodal intraclastic packstone |
Common Grains |
Grapestones & echinoids |
Sorting |
Bimodal |
Rounding |
Mixed well rounded to angular |
Micritization & envelopes |
Micritized grapestones & bioclasts |
Cement & diagenetic fabric |
Mixed spar (some overgrowths) and micrite cements |
Porosity |
None |
Depositional Setting |
High to moderate energy shoal |
Diagenetic history |
Early micrite followed by spar cements |
Skeletal bimodal poorly washed intrasparite from a high to moderate energy shoal. Later the mcrites bind the grapestones & then equant calcite spar cement precipitates when the echinoids develop overgrowths of the same cement
Thursday, November 11, 2021