Ooids ( O/5/Hol/SH.B. )
Outstanding feature | High energy concentric aragonite ooids |
Folk Classification | Well sorted oosparite |
Dunham Classification | Well sorted oolitic grainstone |
Common Grains | Ooids, some quartz and bioclastic grains |
Sorting | Well sorted |
Rounding | Well rounded |
Micritization & envelopes | A few coated grains |
Cement & diagenetic fabric | Meniscus cements at grains contacts |
Porosity | 55% intergranular porosity |
Depositional Setting | Beach rocks along the high energy shoreline associated with algal stromatolite heads |
Diagenetic history | Precipitation of aragonite on pellets, grapestones, bioclasts and quartz, followed by calcitic meniscus cements |
Striking high energy concentric aragonite ooid grains accumulated where they now form beach rocks along the shore of Hamilin Pool of Shark Bay, Western Australia, between intertidal algal stromatolite heads. Note the meniscus cements forming at the points of contact between the grains.
Thursday, November 11, 2021