Arwa (Kimmeridgian to Tithonian) Fm is composed of argillaceous limestone, deep-water lime mudstone, and locally minor packstone, wackestone
, grainstone, and black shale.
Ditrupa- planktonic foraminifera-quartz wackestone
The classification of Dunham, 1962 divides limestone on the basis of texture into grainstone, packstone, mudstone, wackestone
Most Tyndall Stone consists of dolomite-mottled, fossiliferous wackestone
, which was deposited in a stable shelf environment.
The rock slab that contains the crinoids is a medium- to light-brown, poorly laminated, argillaceous wackestone
to carbonate mudstone with a lenticular white chert bed and iron staining.
4-m-thick cyclic interval of thinly bedded wackestone
and nodular clayey wackestone
, which represents shallow-subtidal to tidal-flat deposition.
The Skeletal Lithofacies contains articulated bivalves in life position as well as patches of wackestone
, indicating considerable heterogeneity of fabric.
Palynofacies Lithology 1 Lime mudstone 2 Wackestone
, Packstone 3 Coal 4 Siltstone, shale Palynofacies Characteristics 1 Predominantly amorphous organic matter ([greater than]90%), few marine microfossils and wood 2 Dominated by amorphous organic matter (50%), followed by black debris, brown-black debris, marine microfossils, wood, cuticles, and Sporomorphs in that order 3 Brown-black debris dominant (45%), followed by wood and black debris and sporomorphs 4 Variable numbers of all types of Palynodebris
5 m, is an ostracod thrombolitic wackestone
in which ostracods dominate with some stromatoporoid and porostromate problematica.
These deposits include different textures ranging from wackestone
5 m thick pure skeletal wackestone
layers with Sauvere-type concentric burrows, and pyritized discontinuity surfaces.
The upper Fusselman is dominated by widespread thick, crinoidal grainstones, and lesser amounts of dolomitic wackestone
to skeletal packstone.