Some Foraminiferal Taxa in the Middle to Late Jurassic Sediments of Kaiya Dome, Kutch

Abstract

The Chari Formation exposed at Kaiya Dome, Kutch yielded a foraminiferal assemblage comprising 41 species dominated by the family Vaginulinidae. A systematic account of 11 species, reported for the first time form the Indian subcontinent, is presented. The foraminiferal assemblage is employed for preliminary interpretations regarding age, palaeoecology, and palaeobiogeography. The assemblage suggests a Callovian to Oxfordian age for the exposed sequence at Kaiya Dome. A near shore, open marine environment ranging from mid to outer shelf with fluctuating strandline is interpreted on the basis of the recovered foraminiferal assemblage. The Kaiya Dome foraminiferal assemblage exhibits a Tethyan affinity and suggests that the Kutch region, along with neighbouring regions, was engulfed by a shallow southwestern arm of Tethys during Middle to Late Jurassic times.

Jurassic Foraminifera from the Dharang Member, Habo Formation, Habo Dome, Kutch, India: systematics, age, palaeoecology and palaeobiogeography

“…Astacolus filosa has a global range of Bajocian to Kimmeridgian (Said & Barakat 1958;Kalantari 1969); however, in India it is restricted to the Callovian (Gaur & Talib 2009;Gaur & Singh 2000). Vaginulina misrensis has a global range of Bajocian to Kimmeridgian (Said & Barakat 1958;Kalantari 1969) but in India is restricted to the Callovian (Gaur & Talib 2009;Talib et al 2012a;Jain & Garg 2014). Nodosaria dispar has a global range of Pliensbachian to Callovian (Franke 1936;Sivhed & Wallwork 1978;Smole n 2012;Franz & Knott 2012); however, in India it is restricted to the Callovian (Kalia & Chowdhary 1983, Jain & Garg 2014.…”

“…Reophax metensis has a global range of Pliensbachian through to Kimmeridgian (Said & Barakat 1958;Nagy & Johansen 1989;Samson 2001;Nagy et al 2010Nagy et al , 2011; however, in the Indian region it has been reported only from the Callovian of Kutch (Talib & Faisal 2007). Citharina clathrata, though having a longer global range of Pliensbachian to Kimmeridgian, is restricted to the Callovian in the Indian region (Bhalla & Abbas 1978;Bhalla & Talib 1991;Talib et al , 2012aTalib et al , 2014Gaur & Talib 2009). …”

“…The Kutch region displays an excellent development of Jurassic rocks ranging in age from Bajocian to Tithonian (Biswas 1993;F€ ursich et al 1994, 2001Krishna et al 2000;Krishna 2005Krishna , 2012Rai & Jain 2012). Although the macrofossils of these rocks have been investigated in considerable detail, there are only a small number of studies on the microfossils including the foraminifera (Bhalla & Abbas 1978;Bhalla & Talib 1991;Pandey & Dave 1993;Khosla et al 1997Khosla et al , 2004Khosla et al , 2005Gaur & Talib 2009;Talib et al 2012aTalib et al , b, 2014. These studies indicate that the microfauna, especially the foraminifera, are abundant and well preserved but are in need of a comprehensive review.…”

Jurassic Foraminifera from Habo Dome, Kachchh, Gujarat

“…Eight species of the present assemblages, viz., Haplophragmoides agrawali, H. rajnathi, Ammobaculites alaskensis, A. hagni, Astacolus eritheles, Citharina zaglobensis, Epistomina cretosa, and E. Stellicostata are restricted to Callovian to Oxfordian strata. Out of these, H. agrawali and H. rajnathi, are restricted to Callovian to Oxfordian of Kachchh, India (Bhalla and Abbas, 1978), A. eritheles to Kachchh, India (Bhalla and Talib, 1991), Epistomina cretosa to Kachchh, India (Talib et al, 2012a); and Ammobaculites alaskensis, Ammobaculites hagni, and E. Stellicostata to Kachchh, India (Talib et al, 2012b). Ammobaculites hagni is globally restricted to Callovian to Oxfordian, and C. zaglobensis occurs in Callovian to Oxfordian of Kachchh, India (Talib et al, 2016b).…”