Chhasra Fm (Miocene of India)

Where: India (23.4° N, 68.8° E: paleocoordinates 18.1° N, 68.2° E)

• coordinate stated in text

• local area-level geographic resolution

When: Claystone Member (Chhasra Formation), Burdigalian (20.4 - 16.0 Ma)

• STRATIGRAPHIC RELATIONS: From Claystone Member of Chhasra Fm, which conformably overlies the Khari Nadi Fm (Aquitanian) and is unconformably overlain by the Sandhan Fm (Middle Miocene-Pliocene). AGE: Burdigalian (Early Miocene). Biostratigraphic assignment based on larger foraminifera (see Biswas, 1992). STRATIGRAPHIC POSITION: From Claystone Member, from unknown position within formation.

• formation-level stratigraphic resolution

Environment/lithology: marine; poorly lithified, shelly/skeletal limestone and poorly lithified claystone

• ENVIRONMENT: Environmental data not reported in text.
• SPECIFIC LITHOLOGY: From limestone intercalation, rich in gastropods, bivalves, echinoids, corals, serpulids, bryozoans.

Size class: macrofossils

Collection methods: surface (in situ), hydrochloric,

• COLLECTORs: Unknown, probably Borkar. REPOSITORY: Repository of Geology and Paleontology Group, Agharakar Research Institute, Prune, India. PREPARATION TECHNIQUES: Artificial epoxy resin casts, and HCL dissolution of skeletal material.

Primary reference: K. G. Kulkarni, S. Bhattacharjee, and V. D. Borkar. 2007. Entobian bioerosion of Miocene oysters, Kachchh, Gujarat. Journal of the Geological Society of India 69:827-833 [A. Hendy/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 76317: authorized by Austin Hendy, entered by Austin Hendy on 18.11.2007

Creative Commons license: CC BY (attribution)

Taxonomic list

• COMPLETENESS: Only includes ichnofossil taxa (subject of article) and some bivalvia (oysters), but rich in gastropods, bivalves, echinoids, corals, serpulids, bryozoans are mentioned to be present.
Gymnolaemata
 Cheilostomata - Calloporidae
Planicellaria naliyaensis Guha and Gopikrishna 2007
Reptoporina chhasraensis Guha and Gopikrishna 2007
Bivalvia
 Ostreida - Gryphaeidae
Hyotissa hyotis Linnaeus 1758 Honeycomb Oyster
 Ostreida - Ostreidae
Demospongiae
 Clavulina - Clionaidae
Entobia "sp. A" Bronn 1838 demosponge
Entobia cateniformis Bromley and D'Alessandro 1984 demosponge
Entobia laquea Bromley and D'Alessandro 1984 demosponge