Siwalik Group Research Articles

The late Neogene distribution of C 3 –C 4 plants in the Himalayan Foreland Basin: insight from the δ 13 C values and sedimentological architecture of the Siwaliks

Recent studies emphasize that, in addition to climate-driven forces, sediment grain size and depositional setting with respect to the mountain front significantly influenced the abundance of late Neogene C 3 –C 4 plants in the Himalayan Foreland Basin (HFB). The contrasting depositional settings of the Siwalik Group exposed across the western, central and eastern HFB therefore provide an ideal opportunity to understand the influence of sedimentary architecture on the distribution of C 3 –C 4 plants in palaeolandscapes. To this end, we generate new δ 13 C soil carbonate data from the Siwaliks of the Katilukhad region (12 Ma to 6 Ma) of the Kangra sub-basin and synthesize these data with compiled sedimentological data and δ 13 C values of organic matter, soil carbonate and n -alkane data from the western to eastern HFB Siwalik Group. Our comparison suggests that the rate and magnitude of the positive shift in the 13 C/ 12 C ratios were higher in the floodplain-dominated Siwaliks. Despite an existing conducive climate for the growth of C 4 plants in the late Neogene, the channel-fill-dominated Siwaliks favoured C 3 plants over C 4 plants in the eastern HFB.

Proboscideans from the middle Miocene deposits of Chabbar Syedan in Pakistan

New proboscidean fossils from the Middle Miocene outcrops of Chabbar Syedan in Pakistan are described. The specimens comprise dentary, tusk and symphysial fragments, together with isolated teeth representing four genera and five species: Prodeinotherium pentapotamiae; Deinotherium sp.; Protanancus chinjiensis; Gomphotherium cf. browni; and Gomphotherium sp. A dentary of P. chinjiensis and lower tusk fragment from an adult individual of G. browni are novel reports from the Siwalik Group. Part of a lower tusk with well-developed grooves and a dp2 of Gomphotherium sp. indicate that the Chinji Formation has another gomphotherid species with intermediate-sized tusk and unique dental morphology. The palaeobiogeographical and palaeoenvironmental implications of proboscideans within the context of the Siwalik Group are discussed. Muhammad K. Nawaz [khalilnawaz62@gmail.com], Muhammad A. Khan [akbaar111@gmail.com], Sayyed G. Abbas [ghyour.kazmi@gmail.com], Khalid Mahmood* [khalidkasuri1@gmail.com], Zaman Gul [zaman_gull_1990@hotmail.com] Dr. Abu Bakr Fossil Display and Research Centre, Institute of Zoology, Quaid-e-Azam Campus, University of the Punjab, Lahore, Pakistan; Muhammad A. Babar [babar.zool@uo.edu.pk], Department of Zoology, University of Okara, Okara; Atisham Abbas [syedatishamabbas@outlook.com], Department of Geology, University of the Punjab, Quaid-e-Azam Campus, University of the Punjab, Lahore, Pakistan.

The Concretions from the Middle Siwalik Group of Eastern Himalaya around Buxa Tiger Reserve (BTR), Alipurduar, West Bengal, India

The Concretions from the Middle Siwalik Group of Eastern Himalaya around Buxa Tiger Reserve (BTR), Alipurduar, West Bengal, India

Active tectonics along the mountain front around the easternmost part of the Himalayan Range: Implications for geomorphic evolution

The frontal part of the easternmost zone of the Himalayas is tectonically active, which can be ascertained from different quaternary deformation features like tilted terraces, differential upliftment of terraces, and steep scarps. Along the mountain front, four and three levels of terraces are present on the right and left bank of the Siang River respectively with a maximum elevation of 303 m. Different levels of Quaternary terraces indicate episodic upliftment of the area. On the left bank of the Siang River, 300 m upstream from Dhobighat, the terrace deposits are present at an elevation of 150 m above the Siwalik Group, and 100 m downstream, tilted quaternary deposits are observed. Steep scarps near Mairam, indicate the presence of Himalayan Frontal Thrust (HFT), and based on convincing field evidence, HFT can be categorized into HFT-1 and HFT-2. Total eighteen basins are mapped which are elongated and aligned along the NW-SE direction, parallel to the trend of cross faults present in the area along the Siang River course. The mountain front sinuosity index, SL value, and elongation ratio reflect further that the area is tectonically active. Furthermore, the asymmetry factor and transverse topographic symmetry factor illustrate that all the basins are asymmetric and tilted. Most of the valley profiles are V-shaped, and the valley floor width-to-height ratio is low, indicating rapid upliftment of the area. Lineament maps show a similar trend of the orientation with the major structural features of the area and further, confirm that the area is tectonically active.

Faunal Correlation of Middle Miocene Locality of Chabbar Syedan with Some Other Localities of Chinji Formation of Siwalik Group

Faunal Correlation of Middle Miocene Locality of Chabbar Syedan with Some Other Localities of Chinji Formation of Siwalik Group

Discovery of Parapelomys (Murinae) from the Siwalik Group of Mohand, NW Himalaya: Palaeobiogeography implications

An isolated rodent lower molar is being reported from Mohand II locality (gastropod/otolith locality) of the Siwalik Group exposed in the Mohand area, along the Saharanpur–Dehradun road. The fossils yielding mudstone units from the Siwalik Group exposed in the Doon Valley, Mohand, in the western Himalayan region. The occurrence of this murine mouse lineage, Parapelomys, is consistent with the late Miocene age based on palaeomagnetic reversal stratigraphy. The fossil represents a species apparently more primitive and older than the type species of the genus Parapelomys robertsi. The find documents the geographic range of this mouse lineage 500 km southeast of the type area for the species in the Potwar Plateau, Pakistan. The associated fauna comprises gastropods, ostracods, cyprinid fish and crocodiles in our collection.

Hyperconcentrated floods cause extreme gravel transport through the sandy rivers of the Gangetic Plains

The Gangetic Plains comprise steep gravelly river channels that transition to low gradient sandy channels 10-40 km downstream of the mountain front. This “gravel-sand transition" is characterized by an abrupt greater-than-one-order-of-magnitude drop in both gradient and sediment grain size, suggesting a degree of long-term stability. However, the stratigraphic record of the gravel-sand transition in the Miocene Siwalik Group demonstrates intermittent transport of coarse gravels tens of kilometres downstream of the transition; such events in contemporary channels would drive channel avulsion(s) and increase flood risk, devastating communities across the plains. We combine sedimentological analysis of Siwalik deposits with entrainment calculations which demonstrate that hyperconcentration is required to transport coarse bedload over low-gradient plains. Transport conditions are attainable when intense monsoon precipitation (a 200- to 1000-year event) is combined with increased suspended sediment concentrations in channels. Predicted climate change and ongoing seismicity increase the likelihood of such extreme events within this century.

Mio‐Pliocene exhumation of the hinterland and sediments provenance of the Neogene strata from Kumaun Himalaya of northwest India: Insights from detrital fission‐track thermochronology

Fission‐track (FT) thermochronological analysis of detrital apatite and zircon derived from the lower and middle Siwalik Group of the sub‐Himalaya allows the reconstruction of the long‐term exhumation history of the Higher Himalayan Crystalline (HHC) and Lesser Himalayan Sequence (LHS), and also the provenance of the Siwalik sediments. Here, we report 14 detrital apatite and zircon fission‐track (AFT/ZFT) ages of lower and middle Siwalik subgroups of the Kumaun region, northwest Himalaya. Detrital FT ages suggest that all sandstone samples were never buried below the temperature range of 90° to 100°C and remained as unreset to retain a signal of source‐area exhumation. A detrital AFT age from sandstone sample at close proximity to the Main Boundary Thrust (MBT) is 4.4 ± 0.5 Ma (Pliocene time) which is completely reset and younger than the depositional age, while the detrital ZFT ages of the same sample are unrest. The AFT age represents the time of reactivation of the MBT during which ZFT ages were not affected. This study revealed that the provenances of Siwalik sediments are located majorly in the MBT hinterland areas and the nearest sources are Amritpur granite, the outer Lesser Himalayan meta‐sedimentary (LHMS) zone, Almora klippe, Ramgarh thrust sheet, and the overlying Tethyan Himalayan Sequence. These source areas can be attributed to the development of local drainage networks in the Ramganga‐Kosi drainage basin during late Miocene to Pliocene (i.e., ~9 to 4 Ma). Based on detrital FT datasets, it has been envisaged that different tectonic activities in the MBT hinterland area between Miocene and Pliocene Periods cause the tectonic upliftment and exhumation of source areas and supply the sediment to the Siwalik foreland basin.

New fossil remains of proboscideans from the Siwalik group of Pakistan

ABSTRACT We have described here proboscideans fossil remnants which belong to six species: Prodeinotherium pentapotamiae, Gomphotherium browni, Choerolophodon corrugatus, Protanancus chinjiensis, and Elephas planifrons. The described specimens are collected from six different localities of the Siwaliks. These localities are Bhilomar, Chinji type section, Lawa, Dhok Bun Ameer Khatoon (Chinji Formation), Ochri (Dhok Pathan Formation) and Rathian (Pinjor Formation), belongs to the Lower to Upper Siwaliks, district Chakwal and Jhelum, Punjab, Pakistan. The specimens were collected from these localities after extensive fieldwork from 2015 to 2020, which confirms the presence of large mammalian fauna during the Middle Miocene to Late Pleistocene. Prodeinotherium pentapotamiae is rare taxa in the Middle Siwaliks of Pakistan, first time discovered from new fossil section Satroma wali dhal in the vicinity of the Dhok Bun Ameer Khatoon locality. Bhilomar is a less explored fossil locality belongs to the Chinji Formation, Gomphotherium browni and Choerolophodon corrugatus is reported from the Chinji type section. A beautiful juvenile mandibular ramus of Protanancus chinjiensis has been recovered first time from Lawa and Elephas planifrons were recovered from Rathian which belongs to Pinjor Formation dated as Plio-Pleistocene age of Upper subgroup of Siwaliks. Based on palaeoenvironment and stratigraphy the age of these localities is suggested as Miocene to Pleistocene. The recovered proboscideans fossil fauna indicates about the climatic changes and confirms that more seasonal extensive grasslands and savannah like ecosystem were present at that time.

New Carnivoran (Mammalia: Carnivora) specimens from the Siwaliks of Pakistan and India and their faunal and evolutionary implications

ABSTRACT Recently collected carnivoran specimens from the Siwalik Group of Pakistan are described and discussed. These specimens add to our knowledge of the previously known taxa while also adding to our biogeographic, stratigraphic, and temporal knowledge of the carnivorans from the Siwaliks. At least eight distinct taxa are identified, and although most specimens are fragmentary, some hyaenid specimens are identified further (e.g. Lycyaena and Ictitherium). We identify and describe the first herpestid fossils from the Chinji Formation, the first hyaenid (Lycyaena cf. L. dubia) from the Tatrot Formation, and the first definitive occurrence of Ictitherium (Ictitherium cf. I. viverrinum) from the Dhok Pathan Formation. We report the first occurrences of several taxa from various sites in the Siwaliks of Pakistan, including the first reports of any carnivorans from Dhok Milan, Kohtehra, and Lawa. Individual sites show a wide range of carnivoran biodiversity, however larger scale trends are more discernible when comparing those between formations in the Siwaliks. Several taxa disappear over time from the carnivoran fauna of the Siwaliks, starting with barbourofelines, and continuing with amphicyonids (and non-carnivoran hyaenodontids). Felids and mustelids are the most diverse carnivorans in the Siwaliks, while caniforms become more prevalent through time.

First report on late Miocene (Tortonian: ~ 11–10 Ma) charophyte gyrogonites from Tapar, Kachchh District, Gujarat State, western India

This paper describes the first record of charophyte gyrogonites from the late Miocene (Tortonian; ~ 11–10 Ma) Tapar locality of Kachchh, Gujarat State, western India. The recovered charophyte assemblage is constituted by Chara globularis var. aspera, C. globularis var. globularis, Lychnothamnus cf. sahnii, Lychnothamnus sp. and Nitellopsis sp. In addition, the present article discusses the palaeoenvironment based on the recorded charophyte gyrogonites (this study) and previously known faunal data (mainly vertebrates) from the Tapar locality, Kutch Basin, western India. Further, considering the significant extension of the biostratigraphic range [especially the First Appearance Datum (FAD)] of fauna from the Kutch Basin (in particular from the Tapar locality), we herein make an attempt to compare biostratigraphically the faunal assemblages from Kutch with those from the Siwalik Group, north India.

Petrography and Lithofacies of the Siwalik Group in the Core of Hazara-Kashmir Syntaxis: Implications for Middle Stage Himalayan Orogeny and Paleoclimatic Conditions

The present field and petrographic investigations of the Tortonian to Gelasian Siwalik Group in the core of the Hazara-Kashmir Syntaxis have been carried out to comprehend the middle stage Himalayan orogeny that resulted from the collision of Indian and Asian plates. The Chinji, Nagri, Dhok Pathan, and Soan Formations of the Siwalik Group were deposited by river meandering flood plains, braided rivers, and alluvial fan systems, respectively. The Siwalik Group is classified into seven major facies and many minor facies based on sedimentological properties. According to the petrographic analysis, the Siwalik Group sandstone is classified as litharenite and feldspathic litharenite petrofacies. The sandstone of the Siwalik Group is texturally mature, but compositionally it is immature. The data shown on the tectonic discrimination diagrams point to a recycled orogen provenance field for the Siwalik sandstone. In addition to quartz and feldspar, the sandstone includes clasts of volcanic, metamorphic, and sedimentary rock types. The igneous and metamorphic rock clasts were derived from the Lesser and Higher Himalayas. The sedimentary lithic fragments, on the other hand, are derived from both the earlier molasse and pre-molasse rocks. The presence of lithic fragments of the earlier molasse sandstone in the Siwalik sandstone indicates that the Siwalik Group sandstones were deposited during the Middle Stage of the Himalayan orogeny. The paleoclimatic conditions were semi-arid to semi-humid during the Siwalik Group’s deposition. The presence of clay minerals in the shale reveals the intense chemical weathering processes that occurred during their deposition on the flood plains of the river meandering system.

Distinction of Sivatherium from Libytherium and a new species of Libytherium (Giraffidae, Ruminantia, Mammalia) from the Siwaliks of Pakistan (Miocene)

This study deals with the issues around the synonymization of the large extinct giraffid genera Libytherium and Sivatherium. We performed a morphological and biometrical analysis of the cranial remains of these giraffid genera and resolved this question by formulating criteria to distinguish Libytherium from Sivatherium, and to justify their systematic position within the Giraffidae. The present study also reports a new species of the genus Libytherium, Libytherium proton nov. sp. from the Chinji Formation (late Middle Miocene) and the Dhok Pathan Formation (Late Miocene) of the Siwalik Group of the Indian subcontinent. This extends the biogeographic and biostratigraphic range of Libytherium because this taxon had never been reported from the Siwaliks, Asia and the Miocene before this study. This study also initiates a detailed reassessment of the African and Siwalik material currently attributed to genus Sivatherium (and some other genera) and their proper allocation within the Giraffidae.

Petrotectonic framework of Siwalik Group in Khairi Murat-Kauliar area, Potwar Sub-Basin, Pakistan

The Khairi Murat-Kauliar area lies between the Salt Range Thrust (SRT) in the south whereas Main Boundary Thrust (MBT) in the north which is the part of the Potwar Sub Basin. Eocene to Recent succession is exposed in the study area. The selected siliciclastic Siwalik Group display various facies in a fluviatile environment, with different lithologies, and sedimentary features. The petrographic studies of Siwalik Group delineate different microfacies including feldspathic litharenite, litharenite and sub arkose. The provenance study of sandstones depicted the terrane of dissected arc and recycled orogeny, indicating that the detritus was received from sedimentary, metamorphic, plutonic and volcanic rocks from the northern domain of Indian Plate, Karakoram Ranges and Kohistan Island arc. The Siwalik sandstone also contains heavy mineral assemblage such as tourmaline, garnet, epidote, hornblende and chlorite. This heavy detritus assemblage depicted that the deposits were received from metamorphic and igneous origin. A modified dynamic depositional stages of the Siwalik Group with respect to Himalayan orogeny is further built using outcrop data, microfacies and heavy minerals analysis. According to this concept, the group was deposited along Himalayan uprising and thrusting, on the depository in targeted area. The Siwalik Group depicted different phase of Himalayan tectonics and these molasse sequence were deposited in a subsiding foreland basin under the conditions of rapid erosion and quick deposition.

A gomphothere (Mammalia, Proboscidea) from the Quaternary of the Kashmir Valley, India

AbstractThe Kashmir Valley in northern India preserves a fossiliferous Plio‐Pleistocene sedimentary record extending in time almost 5 myr. These fluvio‐lacustrine sediments are commonly called the Karewas, and represent an ancient lake system with drainages derived from the Greater Himalayas and Pir Panjal Ranges. Although fossils have been known from this region for more than 150 years, the record is not as rich or taxonomically well resolved as the dense fossil record of the southern Siwalik Group. Here, we report the first specimen of a Quaternary gomphothere, cf. Sinomastodonsp. from the Kashmir Valley, along with new occurrences ofEquus cf. sivalensis. This is the youngest gomphothere known from the Indian Subcontinent, representing a group of proboscideans hitherto thought to have gone locally extinct at the end of the Pliocene.Sinomastodonis commonly found in eastern and southeast Asia, and its presence in the Kashmir Valley suggests robust dispersal routes from southeast Asia to the high Himalayas. The presence of this browsing proboscidean in the Pleistocene suggests a unique refugial forested intermontane ecosystem, similar to those found in southern China, different from the savannah ecosystems found in the Siwalik Group south of the mountains.

Evaluating the connectivity of the Yamuna and the Sarasvati during the Holocene: Evidence from geochemical provenance of sediment in the Markanda River valley, India

In the northwest Indo-Gangetic plains, the linkage of the Ghaggar-Hakra paleochannel with the Sarasvati River of early Indian literature and the Harappan (or Indus) civilization poses an important case for understanding drainage reorganization and human-landscape interactions. Among the major paleochannels of the Ghaggar-Hakra, sediment provenance studies on the paleo-Sutlej branch show its connectivity with the Sutlej catchment during the Holocene. However, evaluation of the role of fluvial morphodynamics on the Harappan settlements remains restricted because of limited effort to identify drainage reorganization of the paleo-Yamuna and its connectivity to the Ghaggar-Hakra paleochannel. Here we focus on the sediment deposits in the Markanda Valley, upstream of the northernmost purported paleochannel (Y1) of the river Yamuna, to explore the possible connectivity of the Yamuna catchment with the Ghaggar-Hakra paleochannel through Y1. We analyzed sediment samples from fan surfaces, fluvial terraces, and the modern riverbed for trace element and Sr-Nd isotope geochemistry to identify source signatures. Chronology of the samples, available through Singh et al. (2021), shows aggradation of the fan (57.7 ka) and T-1 to T-5 fluvial terraces during 13.1 to 6.0 ka, and deposition of paleoflood sediment during 3.9–3.8 ka. Results of provenance analysis suggest that sediment in the Markanda Valley was primarily derived from the silicate rocks of the Subathu-Dagshai-Kasauli Formations and the Siwalik Group of the Sub-Himalayas, thus implying that the river Yamuna was not connected to the ancient Ghaggar-Hakra river system (the Sarasvati) through the paleochannel Y1 during the Holocene. The Late Holocene sediment in the Ghaggar-Hakra plains (<4.5 ka), like the sediment in the Markanda Valley, was derived from the sub-Himalaya and transported through Y1, whereas the depositional pathway for the older sediment (>4.5 ka), having sources in the Himalayan hinterland, was likely the southernmost paleochannel (Y2) of the Yamuna.

Thrusting sequence in the Western Himalayan foreland basin during the late phase of continental collision defined by low-temperature thermochronology

Foreland basins associated with collisional mountain belts undergo postdepositional deformation in response to compressive stress exerted from the evolving orogen. The low thermal regime of such processes requires sensitive methods to unravel the structural evolution of such regions. In this study, we conducted apatite fission track (AFT) and (U-Th)/He thermochronology on the sedimentary succession of the Subathu basin in the Himalayan foreland of the Himachal Pradesh region in India, an area preserving the sedimentary record of the India-Asia collision since the late Paleocene-early Eocene. The results show that the Subathu basin exposes a fossilised apatite partial annealing zone (APAZ) depicted by incompletely reset AFT ages and shortened track lengths in the Paleocene-middle Miocene pre-Siwalik units and unreset ages in the Neogene Siwalik Group. We associate the partial annealing of the pre-Siwalik rocks with thickening due to internal imbrication and nappe stacking triggered by shearing along the Main Boundary Thrust and its splays since the middle Miocene. Thermal modelling of the Siwalik rocks projects a rapid heating up to approximately 90–100 °C reached between 4 and 1 Ma. Following the thermal peak, the Siwalik rocks cooled rapidly, as indicated by 2.6–1.2 Ma AHe ages. We associate this recent cooling event with SW-directed thrusting along the Main Frontal Thrust, which placed the foreland basin over the Gangetic Plains. Our results are similar to those obtained for the foreland basin in Nepal, indicating that the movement along the youngest major discontinuity of the Himalaya is synchronous along the orogen.

A supplementary report of the Pleistocene bovids from the Pabbi Hills of Pakistan

The Pleistocene mammalian remains of the Siwalik Group in Pakistan are less described than that of the Siwalik Miocene age. The recent expedition in the Pabbi Hills of Kharian has produced large mammalian remains, predominantly bovids forms. Proamphibos kashmiricus, Kobus sp., Hemibos triquetricornis, and Boselaphus namadicus have been described in this article, based on the new collection. The fourth upper deciduous premolar of B. namadicus is reported for the first time from the Pleistocene of the Siwalik Group. These taxa are large sized and found in the Pleistocene deposits of Pakistan. A Pleistocene savannah‐like landscape is suggested for these two localities.

Sedimentary facies analysis of the fluvial environment in the Siwalik Group of eastern Nepal: deciphering its relation to contemporary Himalayan tectonics, climate and sea-level change

The Siwalik Group, ranging from the Early Miocene to Pleistocene, is believed to be deposited in the fluvial environment and controlled by contemporary Himalayan tectonics and climate. In this study, we established the fluvial environment and its controlling factors responsible for the deposition of the Siwalik succession along the Muksar Khola section in the eastern Nepal Himalaya. Five sedimentary facies associations are identified; these are interpreted as the deposits of flood plain-dominated fine-grained meandering river (FA1), flood-dominated overbank environment (FA2), sandy meandering river (FA3), anastomosing river (FA4), and debris flow-dominated gravelly braided river (FA5). These changes in the fluvial system occurred around 10.5 Ma, 10.0 Ma, 5.9 Ma and 3.5 Ma, defined by existing magnetostratigraphy constraints, due to the effects of hinterland tectonics, climate and sea-level change and continuous drifting of the foreland basin towards the hinterland concerning depositional age. The thick succession of an intraformational conglomerate reveals intensification of the monsoon started around 10.5 Ma in the eastern Nepal Himalaya. The present study also shows asynchronous exhumation of the Himalaya from east to west brought a significant difference in the fluvial environment of the Neogene foreland basin.

New hipparionine fossils from the Dhok Pathan Formation of Punjab, Pakistan

ABSTRACT We visited several late Miocene to early Pliocene localities of the Dhok Pathan and Naragghi villages in the Chakwal district of Punjab, Pakistan and recovered a comprehensive collection of hipparionine fossils. The recently recovered specimens from these localities are compared to the previously collected material of the Middle Siwalik Hipparionini, allowing for the identification of four types of hipparionines: Cormohipparion, Sivalhippus, Hipparion, and Hipparionini indet. The hipparionine horses are common elements of the late Miocene to early Pliocene of the Siwalik Group in Pakistan.