HEAVEY MINERALS ASSEMBLAGE OF QUATERNARY COLUMN OF HOMINID LOCALITY HATHNORA, NARMADA VALLEY DISTRICT SEHORE MP INDIA.

The Narmada river originates from Amarkantak plateau of Satpura Ranges in Rewa at an elevation of about 1057 m (220 40’ -810 45’), it flows westerly course for about 1284 kms length across the middle of Indian subcontinent before entering Gulf of Cambay in the Arabian sea in Gujarat state.The Narmada River course conspicuously straight and is controlled by ENE_WSW to E_W lineament, is bounded by Vindhyan in the north and Satpura in the south. The Narmada valley has maximum length of about 1300 kms and has maximum width of about 32 kms.The Narmada Rift valley formed a linear trench in the middle of Indian subcontinent was an ideal loci for accumulation of sediments. The rift trench is intruded by the dolerite and other mafic and siliceous dykes and sills along lineaments in different phases of tectonic deformation. The Quaternary sedimentation incepting from glacial, followed by fluvio-glacial, lacustrine and fluvial activity.The platform of sedimentation had rinsing and sinking environment, block faulting, linear, displacement and dislocation, uplifting and isolated domal up- lift. The Neogene rifting and quaternary sedimentation, rift-bound Pliocene–Pleistocene rifting and volcanic activity specifically during glacial and fluvio-glacial phase are major component of the Quaternary period and tectonic processes of the Narmada Rift System which form the base of quaternary deposits. The Narmada Valley in the Hathnora area is occupied by thick Quaternary sediments. These sediments are classified based on sedimentary depositional environments, sedimentological characters and correlation with depositional / erosional terraces. The lower rmost unit (Boulder conglomerate) is or glacio-fluvial origin (Khan el al 1991) whereas the rest of fluvial origin. The top four formations (Sohagpur, Shahganj, Hoshangabad and Janwasa) are classified based on morphostratigraphic status (NTo-NT3), degree of oxidation, calcification and compaction. The Janwasa formation comprises of sediments of active domain of Narmada whereas the three formations Sohagpur, Shahganj, Hoshangabad are related to older flood plains deposits of paleo-domain of Narmada and are grouped under older alluvium. Boulder conglomerate of fluvio-glacial origin is assigned an independent formational status based on distinct lithology and fossil assemblage. The sequence of Quaternary events and the history of sedimentation of Narmada indicate that the upper 70 m top 90 m of the Narmad, when dissection of the alluvium resulted two terraces (NT3-NT2). The sediments of this aggradations episode constitute three lithostratigraphy units viz. Boulder conglomerate, Sohagpur and Shahganj formation. The sediments of the alluvial phase are underlain by a boulder bed of glacio-fluvial origin. Thus, the fossiliferous boulder conglomerate, the basal unit of alluvium marks a disconformity between the lower glacial-boulder layer and upper fluvial sediments. The fossiliferous basal boulder conglomerate is being of middle Pleistocene age (Khan 1992). The Quaternary sediments in Narmada represent three distinct group of deposits viz. glacial, fluvio- glacial and fluvial; which was deposited in distinct enviroment in Quaternary times. The Hathnora Section _I to IV (22° 52” N; 77° 58” E) are located around village Hathnora between Sardarpur_Hoshangabad along Narmada from where the 203 sediment samples are collected for heavy mineral studies. In river section 18 m scrap of quaternary sediments consisting of Boulder conglomerate and deposits of fluvial terraces are exposed in increasing antiquity. The Boulder bed is hidden and concealed in the area under younger deposits as such samples have been taken from ongoing bore hole drilling log between the depths of 90 to 201 m below the surface for heavy mineral study. The qualitative and quantitative studies of heavy minerals of Quaternary deposits of different domain revealed five prominent heavy mineral suites viz, opaque suite; amphibole-pyroxene suite, biotite-muscovite-chlorite suite, garnet, sillimanite, kyanite, staurolite suite and zircon, rutile, tourmaline suite. Among these the minerals of opaque suite, is the chief constituents of the heavy residue of sediments in Narmada, in varying frequencies from 10.50 to 39.50 and on average it contributess about 34.30,41.4 0 of total heavy fraction in the entire area of study. The higher frequency of these minerals towards the younger terraces in Narmada is most conspicuous. The minerals of amphibole and pyroxene on the other hand exhibit uniform frequencies; an increase in frequency is noticed towards the terraces of fluvial domain. It is attributed to the exposure of these mineral bearing rocks, such as basics, ultramafic, and volcanic to denudation towards the later phases of sedimentation (Khan et al, in press). The mica group of minerals include muscovite, biotite and chlorite, the over all frequencies of these minerals in the entire quaternary varies from 4.50 to 23.50, muscovite 5.00 to 16.50 and chlorite 2.50 to 7.50 and average frequencies are 18.80, 13.85, 11.75 respectively . These minerals exhibit increasing contribution towards Boulder conglomerate and fluvial terrace depositsof paleodomain The shape,size and their diagnostic physical characters in these deposit implies the extensive erosion of mica-bearing rocks, such as muscovite, biotite schist, gneiss, granite and pegmatite rocks in the headwards ends of Narmada during the early phases of sedimentation. The minerals of high metamorphic suite includes garnet, sillimanite and kyanite the over all frequencies varies from 3.50 to 9.25, 3.50 to 8.50, 9.50 to 7.00 and 3.50 to 6.50 and average frequency is 8.58, 7.75, 5.5 and 5.00. The affinity of higher frequencies of these minerals towards older deposits viz. glacial and fluvio- glacial appears to be due to ready availability of these minerals bearing rocks to erosion. The mineral of stable group viz. rutile, zircon and tourmaline show uniform distribution in the entire domain of terraces in the area of study.The zircon rutile, tourmaline and sphene are highly stable minerals though their abundance is common in quaternary deposit, howeverthey are considered to be very significant as they bear imprints of tectonics, neotectonics and environment of sedimentation . The grain morphology and imprints of sedimentation these mineral bear are of immense significance in understanding the source of sediment, its nature of transportation, mode of transport, kinetics of medium and sedimentation. Their relative frequency in critical column bear significance as regard to tectonic set up of various rock units in the watershed. The contrasting grain morphology of these heavies in the various domains of quaternary deposits are useful in tracing the environments of their deposition. The amphibole and pyroxene minerals with low stability such as hornblende, hypersthene, are more significant as regards to the correlation and chronological status of quaternary deposit. These minerals show variable degree of stability and morphological characteristics, hence these parameters have been taken into account is deciphering the mode of environment of sedimentation and correlation of quaternary deposits in Narmada Valley. The zircon rutile tourmaline and sphene minerals occur as accessories mineral, mostly released from rock fabrics comprising boulder bed and were subjected to different degree of wear and tear and physical condition of weathering transport and deposition, the micro imprints acquired by different condition of sedimentation revealed the intense grounding and bed traction of sediments from the source. The striations on these minerals indicate intense glacial activity in the initial stage of sedimentation. These are generally angular to highly angular in shape and show very poor indices of sphericity and roundness typical of glacial environments. The study revealed that sediments were primarily derived from metamorphic source comprising of kyanite-paragonite, muscovite schist, gneiss, garnet mica schist, and para-amphibolite metasedimentarias and meta-volcanic. Apart minerals were also reworked from older Quaternary deposits from Boulder bed (glacial deposit), Boulder conglomerate of (fluvio-glacial deposit) and older terraces of fluvial domain. These heavies were basically transported from the sources area by glacial fluviol-glacial and fluvial agencies to the present site of their occurrence. The mode of transportation, environment of deposition and energy system of transporting media has greatly affected the frequency and concentration of heavies, their grain morphology and stability in that particular domain. These minerals, mostly released from rock fragments and other fabrics comprising boulder bed, subjected to intensive wear and tear and physio-chemical environment of weathering transport and deposition.Tthe micro imprints acquired by different phases of sedimentation revealed the intense grounding and bed traction of sediments from the source. The striations on these minerals indicate glacial activity in the initial stage of sedimentation. These suites of minerals are stable as compared to the other suite of these deposits; although these mineral are associated with all domain of quaternary deposits but show different frequency of their occurrence and physical characters, shape size shpericity and roundness and bear the micro imprints related with tectonics and environment .The striations on these minerals indicate glacial activity in the initial stage of sedimentation. The configuration of minerals, rock clastic, ground mass, imprints and impact of tectonics revealed the anisometric environments of sedimentation in Narmada valley. The study of heavy mineral suites of Quaternary deposits indicate that the sediments are derived from mixed sediments source comprising of Lower protozoic and middle protozoic rocks consisting of gneisses granite metabolic, amphibolites, meta-sedimentries, high grade biotitie gneisses, muscovite gneisses, kyanite, paragonite, muscovite – schist , gneiss, garnet-mica schist, para amphibolite, tourmaline garnet, meta – sedimentaries and meta -volcanics and Gondwana rocks.