Datta Formation

Jamil et al. (2024) place the Datta Formation as the Early Jurassic base of the Trans Indus Jurassic succession (Datta → Shinawari → Samana Suk).

Jamil, M., Ullah, I., Rahim, H.U., Khan, I., Abbas, W., Rehman, M.U., Rashid, A., Umar, M., Ali, A. & Siddiqui, N.A. (2024)

Butt (1989): in the Hazara Arc the Lower Jurassic Datta/Shinawari transgressive sediments were deposited only in a narrow subsiding mid-portion of the arc (around Baragali), resting on the Hazara Formation and marking a major Precambrian-to-Lower-Jurassic stratigraphic break; the ammonite genus Bouleiceras (Davies and Gardezi 1965) dates them.

Butt, A.A. (1989)

Hemphill & Kidwai (1973, USGS PP 716-B): the Datta Formation is as old as Early Jurassic (late Lias) from an ammonite fauna (L.F. Spath in Heron 1937) ~1 mi SSE of Paniala; varicolored friable micaceous sandstone with subordinate siltstone/claystone and a distinctive pure-white basal sand near Paniala, ~1,470 ft SE of Shaikh Budin (thinning to ~263 ft). The name was introduced by Danilchik & Shah (1973), type section Datta Nala, Surghar Range.

Hemphill, W.R. & Kidwai, A.H. (1973)

Type-section thickness (Shah, 2009): 212 m at type locality; 230 m Punnu Nala; >400 m Sheikh Badin Hills; 150 m Nammal Gorge; 272 m western Samana; 6 m Kala Chitta; 0–10 m Hazara. Type locality: Datta Nala, District Mianwali (principal reference of the Surghar/Broach Group). Recorded from the GSP lexicon (Memoir 22); the existing thickness field is retained.

Shah, S.M.I. (2009)

Calkins et al. (1975): in Hazara the Datta Formation is a thin but persistent red/brown shale and quartzose-sandstone sequence (upper sandstone, middle shale/iron unit, lower sandstone), ~90–160 ft in the Galdanian and Chure Gali areas but exceeding 500 ft westward near the Panjal fault; disconformable on the Kingriali Formation and below the Samana Suk Limestone. Early Jurassic (ammonites; Fatmi).

Calkins, J.A., Offield, T.W., Abdullah, S.K.M. & Ali, S.T. (1975)

Published type section: Datta Nala, Surghar Range (lat 33 deg 00' N, long 71 deg 19' E) — Danilchik & Shah (1973), in Hemphill & Kidwai (1973).

Hemphill, W.R. & Kidwai, A.H. (1973)

Malkani (2016) notes that the Datta Formation is a lateral facies substitution: deposited in terrestrial (fluvial) environments in the upper Indus (Kohat-Potwar) Basin and in marine environments down-slope in the uppermost Indus (Khyber-Hazara-Kashmir) Basin. Curated environment (continental/fluvial/marginal marine) retained.

Malkani, M.S. (2016)

Ahmed et al. (1997), Surghar Range: the Datta Formation is dated by palynology as early Jurassic (Masood & Bhutta 1985) and represents a delta-plain that was drowned by a lower-Toarcian marine transgression at the base of the overlying Jurassic shelf carbonates.

Ahmed, S., Mertmann, D. & Manutsoglu, E. (1997)

Asim et al. (2014): the (Early Jurassic) Datta Formation is among the proven Mesozoic RESERVOIR rocks in the Central Indus Basin (Drigri Anticline–Bahawalpur High seismic correlation).

Asim, S., Qureshi, S.N., Asif, S.K., Abbasi, S.A., Solangi, S. & Mirza, M.Q. (2014)

Calkins et al. (1975): in the Kakul–Galdanian–Chure Gali belt northeast of Abbottabad the middle unit of the Datta Formation carries low-grade sedimentary iron ore — red hematitic claystone/siltstone with layers and lenses of black massive hematite and manganese-oxide (some Mn lenses up to ~1,200 ft long), with oolitic, pelletal and nodular fabrics; it was mapped in detail for economic appraisal.

Calkins, J.A., Offield, T.W., Abdullah, S.K.M. & Ali, S.T. (1975)

Craig et al. (2018): the Early Jurassic Datta Formation is a proven sandstone reservoir, producing oil and gas in the Dhulian, Toot and Meyal fields (Potwar Plateau) and the Chanda and Mela fields (Kohat Basin). It also has source potential in the NW Potwar Basin - Type II and mixed Type II/III kerogen, TOC 1-7.5 wt.%, HI mostly 340-500 mgHC/gTOC (Fazeelat et al. 2010). Notably, Tmax 424-436 deg C indicates it is only marginally mature despite burial >5,000 m, attributed to low heat flow and convective cooling by meteoric waters.

Craig, J., Hakhoo, N., Bhat, G.M., Hafiz, M., Khan, M.R., Misra, R., Pandita, S.K., Raina, B.K., Thurow, J., Thusu, B., Ahmed, W. & Khullar, S. (2018)

In the Kala Chitta Range the Datta Formation is a continental low-stand succession — ironstone/laterite, ferruginous and quartzose sandstone, bauxite and fireclay — filling karstic pouches on the Kingriali surface (Qureshi et al., 2006). The aluminous clays are dominated by kaolinite and diaspore (± gibbsite, hematite, goethite) with Al2O3 up to ~79%; the high-temperature diaspore/hematite assemblage reflects deeper burial and dynamic metamorphism during Himalayan deformation, and sediment was sourced from weathered Indian-shield (Kirana/Sargodha) basement.

Qureshi, M.K.A., Ghazi, S. & Butt, A.A. (2006)