Discussion on “Calcareous algae from the Ordovician succession (Thango Formation) of the Spiti Basin, Tethys Himalaya, India”

Abstract

We congratulate the authors for presenting new data on algae; however, its utility is greatly reduced due to short comings indicated below: 1. The inset in Fig. 1 is wrong, hence misleading. 2. Authors report fossils in 14 thin section of the carbonate rocks and attribute these to the Thango Formation. The Thango Formation is essentially an arenaceous sequence with no carbonate input, thus the stratigraphic location of algal remains becomes suspect. From Hayden (1904) to Myrow et al. (2016) all authors have unmistakably stated that the Thango/ Shian Formation is a non-fossiliferous red-sandstone/quartzitic and conglomeratic succession, deposited in fluvio-marine environment, post the Cambro-Ordovician orogenic event. The calcareous rocks conformably overlie the Thango Formation and are referred as the Takche/Pin Formation. 3. Fig. 1 indicates studied section at Shian locality, but the field photograph in Fig. 2a is of Farakah Muth in the Pin valley. Similarly, the Fig. 2b is not from the Shian locality but from one kilometer south of the Farakah Muth locality. Shian locality lies nearly 5 km south of the Farakah Muth section. 4. According to Suttner (2007) the Pin Formation (280 m) is divisible into Farakh Member (unit P/1–P/6, 0–90 m thick), Takche Member (unit P/7–P/13, 90–230 m thick) and Mikkim Member (unit P/14–P/17, 230–280 m thick). Hubmann and Suttner (2007) reported calcimicrobes and green algae from the units P7 to P11 of the Pin Formation at Farakh Muth section (see Hubmann & Suttner, plate 1 and 2, p. 189–190), Pandey and Parcha‘s (2018) statement that their algal remains come from 72 m below the level of Hubmann and Suttner (2007) section of Farakah Muth contradicts their claim that their samples were from the Thango Formation of Shian section. Kato et al. (1987) reported algae from 58.7 m below the base of Muth Quartzite from the ‘Shaly Limestone’ of the Pin Formation from the Farakah Muth section. The ambiguity of geographic and stratigraphic locations makes the report dubious and contamination in Himalayan palaeontological database. 5. In Table 1, the authors mention that Hubmann and Suttner (2007) used the term Takche Formation, whereas these authors had used the term Pin Formation.