Tamba Kurkur Fm
Type Locality and Naming
Lowest formation in Thinigaon Gr. " The unit, perhaps the most intensively studied in the whole Nepal succession, was introduced in the Spiti-Zanskar Synclinorium of N. India (Srikantia et al., 1980; Srikantia, 1981) and has been subsequently recognized also in the Dolpo±Manang Synclinorium of N. Nepal (Fuchs et al., 1988)."
Lithology and Thickness
Three intervals of pelagic limestone separated by two mudrock intervals. "It was subdivided into five members (three intervals of condensed pelagic carbonates separated by black mudrock intervals) dated precisely with conodonts and interpreted as deposited during alternating transgressive and highstand to lowstand stages (Haq et al., 1988, Fig. 13; Nicora, 1991; Nicora et al., 1992; Garzanti et al., 1992, 1994b). This scheme has been adopted by most subsequent workers.
Relationships and Distribution
Lower contact
Overlies the "topmost biocalcarenites" (Panjang Fm) at top of the Puchenpra Fm
Upper contact
Overlain by the Mukut Fm
Regional extent
"These five members can be traced to S. Tibet, where mudrock units are however locally reduced to thin veneers (Garzanti et al., 1998b). Only the first three are present in central Dolpo, where the Tamba Kurkur Fm. only extends to the Smithian. The Smithian carbonate interval was not recognized in Spiti, where the Tamba Kurkur reaches instead into the Ladinian. The Tamba Kurkur Fm, 23 to 33 m thick in central Dolpo and 37 to 50 m thick in Manang, is reduced to only 6.5 to 8.5 m in the Gyirong-Selong area of western S. Tibet (Garzanti et al., 1998b). Also in the intervening Burhi Gandaki/Shiar area the unit is reduced to a few metres and may be locally missing altogether (Fuchs and Paudel, 1998)." "The third carbonate interval is missing in central Dolpo,
where silt-sized terrigenous detritus is recorded since the Spathian; in the Thakkhola Graben and Manang instead the Tamba Kurkur Fm reaches up to the earliest Aegean, as in S. Tibet (Garzanti et al., 1992, 1994b, 1998b)."
GeoJSON
Fossils
Conodonts
Age
Depositional setting
"Pelagic carbonate deposition characterized the whole Manang area at the end of the Permian ("topmost bio-calcarenites'') and became widespread in the whole of the Tethys Himalaya in the Lower Triassic (Tamba Kurkur Fm.). The interval straddling the Permian/Triassic boundary is commonly marked by significant hiatuses in Nepal (Bassoullet and Colchen, 1977; Nicora, 1991), as in other parts of the Himalaya."
Additional Information
"Drowning of the newly formed Neotethyan margin, associated with a drastic change from siliciclastic shelf to pelagic carbonate sediments was caused by thermal subsidence coupled with sea-level rise at the very beginning of the Mesozoic (e.g. Wignall and Hallam, 1993)."