ON THE GEOLOGY AND CORRELATTION OF COAL SEAMS OF PENCH-KANHAN-UPPER TAWA VALLEY COALFIELD, DISTRICT CHHINDWARA, MADHYA PRADESH H. S. PAREEK 202 E, West End Road, Meerut Cantt. (U.P.) ABSTRACT (22°28': 78°26')" (Fox, 1934). The limits The Satpura Gondwana basin has not drawn as may be taken as from Mohpani (22°45': much attention during the recent years, as other 78°50') on the north to Pathakhera (22°6': basins have from coal geologists for systematic 78°10') on the south, and from Sirgora mapping and coal seam correlation. Hence scat• (22°12': 78°50') in the east to Sonada tered information only is available for parts of coalfields of this basin. The geology of the Pench, (22°16': 77°47') in the west. The coalfields Kanhan and Upper Tawa valley coalfields is pre• included in this basin are Mohpani (22°45': sented in this paper, which also brings out the 78°50') in the extreme north, Pench valley coal seams and their correlation in these areas. As and Kanhan valley in the east, and Patha• all major Gondwana basins have been named after their principal drainage, the term Pench-Kanhan• khera, Dulhara (22° 10': 78°1'), Shahpur Tawa valley basin is preferred to Satpura Gondwana (Tawa) (22°10': 77°54'), and Sonada from basin. east to west on the west. The present The Lower Gondwana formations of the coal• knowledge on their geology exists due to field include the Talchirs, Barakars and Moturs, while separated exposures of the Upper Gondwanas Blanford (1882), Jones (1887), and Fox occur in the Pench valley region. The Talchirs (1934). are in faulted contact with the Barakars in the Of these coalfields', the Tawa valley area northern portion of the coalfield. Faulting is is undeveloped, while the Pench valley has common in the sedimentaries. Three coal seams numbered as I, II and III from been explored and worked out to an extent the top and ofthicknesses 1'22-8' 53m., 0'60-1'82 m., greater than that of the Kanhan valley. and 0'60-2'13 m. respectively, occur within the The Gondwanas occur as a small patch Barakars. The seam characteristics have been near Sirgora, and form a continuous strip presented. A thin seam, named as Leader, persis• tently appears following as a younger seam over from Dighawani (22°12': 78°49') in the east each of the seams II and III. In the Pench valley to Nonkharak (22°11'30": 78°10') in the region the Leader has coalesced with the respective west, being affected by faults at places. seams in certain areas. In seam I, a tonstein band This tract stretching for 63 km. with a appearing microscopically as sandy carbonaceous kaolinitic mudstone grades laterally into shale and width of 8 to 10 km. is traversed by the siltstone. rivers Pench, Kanhan and Tanbia (Upper Tawa). These coal-bearing areas represent INTRODUCTION the Pench-Kanhan-Upper Tawa valley Coal• field, and this paper presents its geology, and occurrence and correlation of coal coalfields of India are restricted to the seams, as studied by the author. As is well-known, the major Gondwana . fresh-water basins named as the GEOLOGY OF THE COALFIELD Damodar valley, Mahanadi valley, Wardha• Godavari valley, and Satpura Gondwana All the major basins of Gondwana de• basins. The attention of coal geologists position owe nomenclature to their principal that has been drawn is of a lesser signi• drainage system, and hence the Pench• ficance with respect to the Satpura Gond• Kanhan-Tawa valley basin is preferable to wana basin, possibly because the coal seams Satpura Gondwana basin. The Pench are of comparatively lesser thickness, and valley, Kanhan valley and Upper Tawa the areas are under-developed with problems valley areas cannot be demarcated sharply of means of communication. from one another and have accordingly The Satpura Gondwana basin includes been described as the Pench-Kanhan-Upper " the hilly region of Hoshangabad, northern Tawa valley coalfield (Pareek, 1969a). The Chhindwara and north-east Betul. In it geological sequence of the rock formations lie the Mahadeva hills around Pachmarhi in the coalfield is as follows. 95 96 THE PALAEOBOl' ANIST Recent Alluvium Text-figure 1 shows the geological map Upper Lava flows (Deccan Trap) and dykes Cretaceous of dolerite, sometimes Olivine-bear• of the area covered. The general strike of ing. the sedimentaries is ENE-WSW, and the dips are northerly, varying from 5° to 15°. ...... Unconformity . Strike faulting is quite common and the Upper Jabalpur Stage: Clays, massive sand• fault zone is marked by silicification. The Gondwana stones, often gritty, and Carbonaceous Gondwana patch near Sirgora owes its shales in the Sirgora area. preservation due to two parallel strike .................. Unconformity . faults. The patch of Talchirs near Chhinda Lower Motur Stage: Yellowish sandstones, (22°12': 78°51') has its southern side in Gondwana mottled red, buff, yellow and green faulted contact with the traps and the clays, often with calcareous nodules. northern side with the Barakars and the Red clays diminish westwards being traps, as seen in the Pench. A tributary of practically absent in the Upper Tawa valley .450-610 metres. the Pench has meandered along the strike Barakar Stage: l\Iedium to coarse• faults, before enjoining the Pench. A small grained sandstones, shales, carbonace• patch of Barakars is also preserved in be• ous shales and three interbedded coal tween the Moturs. An ENE-WSW fault also seams 120-130 metres. Talchir Stage: Greyish, greenish to dislocates the Barakars, west of Jamkunda, olive-green shales, claystone, fine• where the Talchirs are in direct faulted grained sandstones with undecom• contact with the Moturs. This can be posed felspar, and boulder bed. considered as the arbitrary boundary for .................. Unconformity . demarcating the coal-bearing areas of the Pench and Kanhan valleys. Archaean Metamorphics: Granites, often porphy- ritic, hornblende gneiss, schists and A number of strike and dip faults exist amphibolites. in the Kanhan valley region. One strike fault stretches for a distance of 24 km., being affected by a dolerite dyke in the The Kanhan valley exposes the full se• Ghorawari Khurd (22°11': 78°15') area and quence of rock formations in the coalfield. by a NN E-SSW fault near Damua (22°12': The boundary between the sedimentaries 78°28'). Faults are also very common and metamorphics is faulted and so also of the Talchirs and Barakars. The exact within the traps. thickness of the Talchirs is difficult to be DESCRIPTION OF THE ROCK FORMA• ascertained since they rest unconformably TIONS on irregular surface of the basement rocks and are in faulted contact with the over• T alchirs: The surface soil concealing the lying Barakars. A total of 1000 m. of the Talchirs below is marked by a greyish to Lower Gondwana strata reducing in thick• greenish colour of the fragments and splin• ness westwards exists in the coalfield. The ters of the Talchir shales. It is only along Barakars grade into the Moturs at some the railway cuttings, nalas, and river sec• places, while they are in faulted contact at tions that the Talchirs are well-exposed. others. Scattered outcrops of the Upper The rocks include greyish and khaki-greyish Gondwana occur in the Pench valley region shales, greenish sandstones, boulder bed, and their typical sequence is in the area and greenish to olive-green claystone, around Sirgora. characterized by spheroidal weathering The Deccan Trap co\'ers most of the (Pareek, 1968). Varves so common in Pench valley region, concealing the Gond• other coalfields (Ghosh, 1962; Pareek, 1965) wanas specially in the eastern portion of are not of any conspicuous occurrence. the coalfield. The trap exposures also No well-preserved plant fossils were avail• occur due south of Barkui (22°11': 78°42'), able. and from its east towards Dighawami and Barakars: The sequence exhibited is shale, Sirgora. Scattered exposures also appear carbonaceous shale and sandstone grading all round Chandameta (22°11'30": 78°44'). from fine to coarse-grained; shale, siltstone, Dykes of dolerite are also spread through• and shaly sandstone; shale, carbonaceous out the area. Most of the Pench-Kanhan• shale, shaly coal and coal. The sandstones Upper Tawa area is, therefore, covered by exposed in the river valley sections are the Talchirs, Moturs and the Deccan Trap. massive although bedded, and exhibit big "0 >• ;!:::-.40-, ~ tI1 "" tI1 ~ I ~'.'G<>J~ ,~ :: 00 ~ ....~: o t"' GEOLOGICAL MAP OF PENCH - tC;ANHAN VALLEv COALFIELD, MA.DHYA PRADESH o seA\.£ 1M I(ILOII[".U'- ~ &!D JABAL PUR ~.MOTUR ~ (EX] ARCHA[.t.H Ij i OlPS n o ~ TEXT-FIG. 1 - Geological map of Pench-Kanhan Valley Coalfield, Madhya Pradesh. ~ S o..... Z o "Ij n o ~ SKETCH MAP SHOWING COLLIERIES OF' gj PENCH'KANHAN VALLEY COAL FIELD, ~ DISTRICT CHHINOWARA. M P ",,,,,~\--- ----- •... -' " \.0\ [J) /_. ~ I o C"""'O" I:' \ Slll.O." ~ "Ij ~/.UtlA ••• v••o1 1 ............t_-_...- -', - - ......•..•_ .....!- --Ll:G(NO CIt!OA ~~\.Ct::"'",::c con,U1' '."."'tIlO\. cou., I ~ _IIOAD __ IIA~.'" ____ V1\.LAUaouNIU •• 'I' ~ TEXT-FIG. 2 - Sketch map showing collieries of Pench-Kanhan Valley Coalfield, Dist. Chhindwara, M.P. ~ ::r: ~ "-.0 98 THE PALAEOBOTANIST pot holes. They are interbedded with mica• to seam I, while the two seams of Sirgora ClWUS sandstones and comprise angular are a correlate with seams I and II. quartz grains, altered felspars and limonitic One thick seam numbered as I is being stains. The shales are greyish, occasionally actively worked in the Kanhan valley area. grading into carbonaceous shales. The Two thin seams numbered as II and III are Barakars contain three interbedded eco• being worked in the Ghorawari area. A nomically workable coal seams.