Albian Ammonites from Northern Pakistan

Albian Ammonites from Northern Pakistan

DE DE GRUYTER Acta Geologica Polonica, Vol. 64 (2014), No. 1, pp. 47–98 OPEN DOI: 10.2478/agp-2014-0003 G Albian ammonites from northern Pakistan WILLIAM JAMES KENNEDY1 AND ALI N. FATMI2 1Oxford University Museum of Natural History, Parks Road, Oxford OX1 3W and Department of Earth Sciences, Parks Road, Oxford OX1 3AN, United Kingdom. E-mail: [email protected] 2Formerly of the Geological Survey of Pakistan, Quetta, Pakistan (Dr Fatmi died on 27 March 2012) ABSTRACT: Kennedy, W.J. and Fatmi, A.N. 2014. Albian ammonites from northern Pakistan. Acta Geologica Polonica, 64 (1), 47–98. Warszawa. The occurrence of rich Albian ammonite faunas in what is now northern Pakistan has been known for more than 80 years, but there has been no comprehensive account of the assemblages present. A total of 36 taxa are described below. The middle part of the Lumshiwal Formation yields Upper Aptian ammonites south of the Samana Range. Elsewhere, it yields Douvilleiceras leightonense Casey, 1962, of the lower Lower Albian Leymeriella reg- ularis Zone and the Sonneratia perinflata and S. kitchini Subzones of the Sonneratia chalensis Zone of the north- west European sequence. The top one to two metres of the Lumshiwal yields an abundant fauna of rolled and phos- phatised ammonites that includes elements from much of the Albian. Of these, Prolyelliceras gevreyi (Jacob, 1907) first appears in the lower Lower Albian Leymeriella tardefurcata Zone. The commonest ammonite is Douville- iceras mammillatum (Schlotheim, 1813) sensu lato, which ranges from the perinflata Subzone of the chalensis Zone to the Otohoplites bulliensis Subzone of the O. auritiformis Zone of the Lower Albian. The presence of Lyel- liceras pseudolyelli (Parona and Bonarelli, 1897) indicates the uppermost, pseudolyelli Subzone of the auritiformis Zone. The presence of Lyelliceras lyelli (d’Orbigny, 1841) indicates the basal Middle Albian lyelli Subzone of the Hoplites dentatus Zone. There is no evidence for the higher parts of the Middle Albian. Dipoloceras (Rhytido- ceras) sp. indicates the presence of lower Upper Albian, possibly the pricei Zone. There is evidence, in the form of specifically indeterminate Mortoniceras (Mortoniceras) sp., of a level within the inflatum to fallax Zone inte- val from a single locality, but no evidence of the succeeding parts of the upper Upper Albian. The base of the Kawa- garth Formation that succeeds the Lumshiwal yields lower Upper Albian Mortoniceras (M.) geometricum Spath, 1932 of the Mortoniceras pricei Zone, northwest of Darmasand in the Samana range. Key words: Ammonites; Cretaceous; Albian; Pakistan. FORWARD: I never met Ali Fatmi, who died on 27 March 2012 in Karachi. We had corresponded, and occasionally spoken on the phone for more than a decade. This paper is dedicated to his memory. INTRODUCTION British geologists employed by the Geological Survey of India. The ammonites were briefly described and illus- The presence of Lower Cretaceous (Albian) am- trated by Spath (1930, 1934a), prior to partition in 1947. monites and other invertebrates in the Hazara Ranges and One of us (ANF) revisited these areas in the 1960’s, ac- adjacent areas in the Northwest Frontier Province of companied by Ms M. R. Khan and Mr I. H. Hydari of what is now Pakistan (Text-figs 1, 2) was first noted by the Geological Survey of Pakistan, and collected faunas Unauthenticated | 89.73.89.243 Download Date | 5/2/14 5:49 PM 48 WILLIAM JAMES KENNEDY AND ALI N. FATMI from known localities and many new ones. These local- Spath (1930) briefly described what would now be ities are in the Nizampur, the Kohat Tribal Belt, Samana, regarded as upper Middle and lower Upper Albian am- and Daramsand areas (Text-fig. 2). Fatmi (1972, 1977) monites from the Hazara Ranges, noting the dominance redefined the stratigraphy of the Mesozoic rocks in the of Lyelliceras over Douvilleiceras (Pascoe, 1959, pp. region, including the ammonite-bearing Lumshiwal For- 1311–1313). mation. The ammonite localities in the Kohat and Per- Cotter (1933) and his associates carried out the first shawar districts lie close to the east and west trending detailed stratigraphic studies in the Kalchitta Range. Kohat Tribal Belt that intervenes between the Pershawar Their fossil collections, from the upper part of the Giu- district to the north and the Kohat district to the south of mal Formation (Text-fig. 3 ; = Lumshiwal Formation the Northwest Frontier Province. The outcrops in these herein) were described by Spath (1934a; cephalopods), areas are excellent, rimming the Jurassic cores of anti- Cox (1935: bivalves and gastropods), and Muir-Wood clinal folds, but access is severely restricted due to the (1937; brachiopods). The presence of the ammonite tribal and semi-tribal nature of the country. Fieldwork is Oxytropidoceras indicated the Middle Albian. safer in the Kalchitta area of Punjab Province and the There is no published information on the Cretaceous Hazara area of the Northwest Frontier Province, but ex- ammonite faunas of the Nizampur region and the ad- posures are poorer because of the vegetation cover and joining Kohat Tribal Belt. General observations on these the isoclinal and recumbent folding of the sequence, areas are to be found in Pascoe (1959, p. 1169, 1314). which lies close to the main boundary fault system on the Davies (1930) was the first to define the Mesozoic margin of the Kohat-Potwar Plateau (Text-fig. 1). successions in the Samana Range (Text-fig. 2). His fos- The history of the development of the stratigraphic sil collections were described by Spath (1930: nomenclature of the Cretaceous rocks of Hazara to the cephalopods), Cox (1935; bivalves and gastropods), east, the central Kalachitta area, and the Samana Range and Muir-Wood (1937: brachiopods). The upper beds of to the west are summarised in Text-fig. 3. Davies’ Main Sandstone Series (Text-fig. 3; = Lumshi- Text-fig. 1. Mesozoic outcrops of the upper Indus Basin, northern Pakistan Unauthenticated | 89.73.89.243 Download Date | 5/2/14 5:49 PM 49 CRETACEOUS AMMONITES FROM PAKISTAN Text-fig. 2. Fossil localities in Hazara, Kalachitta, Nizampur, and Kohat, northern Pakistan wal Formation herein) yielded ammonites including 3. Upper Cretaceous: Kawagarth Formation: open ma- Douvilleiceras, and were regarded as Middle Albian rine carbonates with planktonic foraminifera. (Pascoe 1959, p. 1296–7). UNCONFORMITY 2. Aptian-Albian: Lumshiwal Formation: continental clastics in southern sections; shallow marine clastics STRATIGRAPHY or mixed shallow marine clastics and carbonates in northern sections. Mesozoic rocks are widely exposed in the deposi- 1. Upper Jurassic to Lower Cretaceous: Chichali For- tional basin in northern Pakistan known as the Upper In- mation: shallow marine clastics. dus Basin (Text-fig. 1). The southern outcropping sections The ammonites described here come from the include the Salt Range (western half) and the Trans Indus Lumshiwal Formation in northern sections from Hazara Ranges (Surgar Range, Khisor Range, and Sheik Budin in the east to the Samana Range in Kohat to the west Hills). In these sections only Lower Cretaceous rocks are (Text-fig. 2). The Lumshiwal Formation is variable in present. They are shallow marine in the lower part and both facies and thickness. It is mainly quartzose, glau- continental in the upper part. They are disconformably conitic and ferruginous in the Samana Range and Dar- overlain by Palaeocene sediments. The northern out- masand in Western Kohat, Mian Ghari Korez in the Ko- crops of Cretaceous rocks lie in the Hazara-Margala Hills hat Tribal Belt. At Kuhi, in the Kohat Tribal Belt, Ziarat (Northwest Frontier Province), Kalchitta (Punjab), Fateh Gul, Nizampur, northern Kalchitta, south of At- Nizampur and the adjoining Kohat Tribal Belt (Northwest tok, and the Jabri section, southern Hazara, it is made up Frontier Province), and Western Kohat (Samana Range of quartzose glauconitic calcareous sandstones and and adjoining Darsamand and Khodi-makh), where shal- shelly limestones. In northern Hazara (Chiriala-Kala- low- marine Lower Cretaceous rocks are disconformably pani) it is represented by the ‘Giumal’ facies of Kash- overlain by Upper Cretaceous carbonates. mir (see Lukeneder et al. 2013), a much reduced thick- The generalised sucession in the Upper Indus Basin ness of brownish massive calcareous ferrugineous is as follows, although it should be noted that Upper sandstone (Text-fig. 6). The sequence reaches its max- Cretaceous rocks are absent from the southern sections imum thickness of 204 m (670 feet) in Western Kohat, in the Salt Range, Trans-Indus Ranges, and southern 67 m (220 feet) in Nizampur, 58 m (190 feet) in Kalchitta (Text-figs 4, 5): Kalchatta, 54 m (177 feet) in southern Hazara Unauthenticated | 89.73.89.243 Download Date | 5/2/14 5:49 PM 50 WILLIAM JAMES KENNEDY AND ALI N. FATMI Text-fig. 3. History of development of Jurassic and Cretaceous stratigraphic nomenclature of northern areas of Pakistan: Hazara, Kalachitta, Nizampur, and Kohat Jabri/Jabrian section, and 9.7 m (32 feet) in northern the pricei Zone of the north-west European sequence Hazara (Chiriala-Kalpani section) where Upper Juras- (Text-fig. 7). sic and Lower Cretaceous ‘Giumal’ and ‘Spiti’ facies are The Lumshiwal Formation is generally poorly fos- developed (Text-figs 4, 6). siliferous below the topmost unit, apart from fragmen- The Albian ammonites described here are predom- tary molluscs and echinoids. The Wuch Khar section inantly phosphatised moulds, sometimes with phos- southeast of Nizampur (Text-fig. 6) has yielded large phatised shell preserved. Most were collected from less ammonites up to 90 cm in diameter. Also present is a than a metre to about two metres of the uppermost, lower Lower Albian Douvilleiceras leightonense Casey, fossiliferous unit of the Lumshiwal Formation devel- 1962 (Text-fig. 26J), which is well-dated as regularis oped in these areas. This is a well-cemented gritty, cal- Zone and perinflata and kitchini Subzones of the careous, ferruginous, glauconitic sandstone or well ce- chalensis Zone in the north-west European sequence mented sandy limestone.

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