Palynodating of Subsurface Coal Measures from Mahadoli Area, Wardha Valley Coalfield, Maharashtra, India
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Pataeobolani.vl 5 1(2002) : 93-98 0031-0174/2002/93·98 $2.00 Palynodating of subsurface coal measures from Mahadoli area, Wardha Valley Coalfield, Maharashtra, India A.P. BHATIACHARYYA ANOO.S. SARATE Birbal Salmi Institute of Palaeobotany, 53 University Road, Lucknow 226 007, India. Email: ossarate@hotmai/.col1l&[email protected] (Received 12 April 2001; revised version accepted 06 August 200 I) ABSTRACT Bhattacharyya AP & Sarate as 2002. Palynodating of subsurface coal measures from Mahadoli area, Wardha Valley Coalfield. Maharashtra. India. Palaeobotanist 51 : 93-98. Two palynoassemblages have been recorded from the Permian Sequence of Mahadoli area (Borehole WM-14), Wardha Valley Coalfield. Maharashtra. The older palynoassemblage A is Scheuringipolleniles dominant while the younger palynoassemblage B is characterized by Parasacciles-Densipolleniles along with striate bisaccates. Falcisporiles and Salsangisacciles. Correlation with palynoassemblages of other coali ferous basins of India and the age of subsurface sediments have been discussed. Key-words-Palynoassemblage. Barakar, Permian, Wardha Valley Coalfield. India.. ~ ~ ~ 'li?lsl~ ~ ~ ~ ~ ~ ~ 'qffif ~ 'li?1 (Its<; ~ ~ qqf ~ ~ ~ i3q~~ CiiT q(1'1I°I(4Cfi f.fm ~ ~ ~ ~~T ~ ~ -3FR1 5I1lK mu~ ~ ~ ~ ~ ~ (~q ~.c;q.-I4) ~ ~ ~ ~ ~ ~ qqf QTtt fm' B ~ ~ ~ ~ ~ ~ ~ ~ ~~n'fiq}&'1I$tiJi ~ ~, ~ fctT:( I lW4R if <n'T ~ ~ ~ ~f1q))felqj, ~ ~ BT~-BT~ 1<fR oft if m'ft 'filfRtp.{JO$ti'1 Arft"MWiI$tiJi ~ ~ ~ ~ ~ ~ ~ ~ BT~ ~OtlWiI$tlJi grHJq}&'1I$tiJi <n'T I 'lffid' <n'T -3Fi tlrtl ~ ~~ ~ ~ ~ ~ ~ ~ ~ ~I <n'T if qqf <n'T 1f4t ~ ~-~ ~' ~, ~, qqf QTtt ~ ~, ~I INTRODUCTION Geology and Mining. Government ofMaharashtra is presently engaged in coal exploration in Mahadoli area. (longitudes HE Wardha Valley Coalfield has recently emerged as one 78°54' IS" and 20°21 '4S"latitudes) for the possibilities ofcoal T of the main resource for coal exploration through Open reserves in the virgin tracts of the Coalfield through subsurface Cast Mining. The main coal centers are localized in Chandrapur study. General stratigraphic succession of Wardha Valley and Yeotmal Districts of Maharashtra. The Directorate of Coalfield, Maharashtra is given below [after Raja Rao,' 1982 (fig. I») © Birbal Sahni Institute of Palaeobotany, India 94 THE PALAEOBOTANIST Age Group/Formation Lithology Recent Alluvial gravel beds, black colton soil ') Eocene Deccan Trap Basalt Cretaceous Lameta Formation Limestones. chcns and silicified sandstones ---------- Uncon form ity------- Upper Triassic Maleri Formation Fine to medium-grained (only in the south-eastem sandstones and red shales extremity) Upper Permian Kamthi Formation Red, brown and variegated Lower Triassic sandstones, reddish siltStones and variegated shales --------- Unconformity-------- Lower Permian Barakar Formation Light grey to white sandstones. Shales and coal seams ') Upper Talchir Formation Tillites. turbidites. varves. Carboniferous needle shales and Lower Permian sandstones --------- Uncon formi ty------ -- Precambrian Sullavi Sandstones White to light brown quanzitic sandstones. conglomerates --- ---- ------0 ve rI ap-- ---- ----- Pakhal Limestones Grey, bluish or pinkish limestones and chens ---------- Uncon t'ormi ty------- Archaean Quartzites, granite gneises. etc. Fig. I-Generalised stratigraphic succession of Wardha Valley Coalfield. The borehole passes through Deccan Traps, Lameta, are represented by Parasaccites with maximum occurrence of Kamthi and Barakar formations. Grey shale, sandstone, clay 18 per cent along with Caheniasacciles. (11%). Other and carbonaceous shale characterize the Barakar sediments. monosaccates are Virkkipollenites, Crucisaccites and The present study has been carried out in order to establish Potonieisporites. Trilete spores are represented only by palynological succession and its correlation with other Verrucosisporiles. Tiwariasporis is present up to 118 m depth. Gondwana Basins of India. Amongst striate bisaccate pollen, Slrialiles and The location of the borehole WM-14 is shown in Fig. 3 StrialOpodocarpites are subdominant forms. Weylmuliles and and the lithological succession present in the borehole is Ginkgocycadophytus are found to be 3% each. shown in Fig. 2. The occurrence of spores and pollen at 125 m is meager. Two palynoassemblages have been recorded from hence the percentage frequency could not be estimated. borehole WM - 14. The distribution and frequency of spores However, on the basis of taxa present, this level is considered and pollen ofstratigraphic importance have been plotted (see to represent a part of the palynoassemblage A. fig. 4) to show their relative abundance through the entire depth of the borehole. Some important spores and pollen have Palynoassemblage-B been illustrated in PI. l. Occurrence-Borehole WM-14 (at 66,25-76·00 m depth). Palynoassemblage-A Lilhology-Micaceous sandstone, Carbonaceous shale. The palynoassemblage is characterized by the dominant Occurrence-Borehole WM -14 (at 106-118 m depth). presence of Parasaccites (21 %) along with striate bisaccate Lilhology-Grey shale, Carbonaceous shale, Fine genera Slriatopodocarpites and Fallllipollelliles (15%, each). grained .sandstone. Falcisporites (5%) and Smsangisacciles (6%) have also been Scheuringipollenites (32%-26%) is dominant in this recorded, along with other nonstriate genera, such as assemblage (see Fig. 4) followed by Ibisporites (10%). The Alisporites (2%) and Platysaccus (3%). Other monosaccate taxa Rhizomaspora (8%)and Prillluspolleniles (8%-3%) are genera, viz., POlOnieisporiles (3%) and Densipolle/liles (9%) frequently met within this assemblage. Monosaccate genera also record their fair occurrence in this assemblage. BHATIACHARYYA & SARATE-PALYNODATING OF SUBSURFACE COAL MEASURES FROM MAHARASHTRA ')5 Depth Sample close affinity with Lower Barakar mioflora reported from (in meter) Position Godavari Valley coalfields by Srivastava and Jha (1989.1998). 0.0 Scheuril1gipollelliles dominant zone has also been recorded 1.50 from Pathakhera Coalfield, Satpura Basin, Sarate (1986). Agashe and Chitnis (1972) reported Lower Barakar palynoflora from Hindustan-Lalpet Colliery containing dominance of Brevitrileles and Scheurillgipollelliles. Similar palynoflora has been recorded by Agashe and Geetha (1979) from Kamptee v Coalfield with dominant Scheurillgipollelliles and striate v v v bisaccate taxa but the present assemblage differs in the presence of monosaccate taxa Parasacciles and 64.90 ~v . v00\0606V v I 65.60 06-_-_- • Cahelliasaccites in high percentage. The present assemblage is comparable to the palynozone -V of Tiwari and Tripathi :'.:::.~::. ~ ~'.~: .: '.:.: ': Sea Ie (m.) (1992). .,. '" ' ." •••••• 0-' '.. The Palynoassemblage -B is characterized by the 72.82 •• ' o presence of Slriatopodocarpites and Faullipollelliles (lYle each) along with Scheurillgipollel1iles in low percentage. -------••••••• '" 76.71 a 0 5 However, Parasacciles (21 %) and Dellsipollelliles (9%). the monosaccate genera are prevalent. The occurrence of 10 DellSipol/el1ites magnicorpus along with striate bisaccates is .V· well established in Late Permian mioflora of Damodar Basin. ':".~'.: .<:~'.: :~":'~'~~'<~:::: However, Falcisporites and Satsallgisaccites suggest ,:.:.: :. :.:.: :.: :":' :':':: 15 younger aspect of the palynoassemblage. The reCUITence of Parasaccites with striate bisaccate has been reported from 103.65 ~':'.':':>"::~:'.~ ::~'/:.\:/~ Godavari Valley and Supra Barakar Formation in the Son 103.85 Index ------:-:~:~'."'::'.~'~ .~. Mahanadi Valley also. The Palynoassemblage -B is closely Q Alluvi urn comparable to Palynozone - 9 of Middle member of Kamthi Formation in Godavari Valley (Srivastava, 1992). Similar ': .~.~.:.~ (~'.\:'~':"::. ')': Ivv v I Daccan Trap 111.94 .............. palynoassemblages have also been recorded from Jaipuram -------............. area (Assemblage in the borehole GJP-I; Srivastava & Jha, 115 25 ;-;;-.-: :-. -:-."7 : ,ooe~()\}I Conglornarate .I I , f I I Il I 1992), Ramakrishnapuram area (in borehole GJRK- 25). 117.62, I' t t { r II 13- - Shale Bhopalpalli area (Palynoassemblage - III, Srivastava & Jha. ~ 1998), Johilla Coalfield, Son Valley (Tiwari &Ram-Awatar 1989). 118.30 0~.~ \~ ~ ~.: ':\:.::.:': 0.... Sand stone and from Supra Barakar sediments in Son Valley (Assemblage - 5; Tiwari & Ram-Awatar, 1987). The occurrence of ~ Clay 125.90 UljJl~iSi ~J 126.40 ........... ~ Carbo shale SCALE ogn --- !N, .... : \ Fig. 2-Showing the levels of yielding samples in the lithological suc ! ''''''', , cession . J-"' / ,l\ The shale at 76·00 m depth contains lesser frequency of : :'~.. spores and pollen grains but since it contains D. l1Iagl1icorpus " ,:'It "G,',., :: .. (2%), it is preferred to retain it in Palynoassemblage B. ~. .. :!. '" / : OhO~OI' ~HW""-li. ~ ~ ;. .~. " COMPARISON I ./" : .. ~ ,; '::''''~ ./ o ::J!;"awo 70" A Scheuringipollel1ites dominant mioflora has been ,: :'>( reported from the lower part of the Barakar Formation in //<"/./ ,...,.... ~. Damodar Basin, Son Mahanadi Basin, Satpura Basin and :-" .... .A.SI .'",". Godavari Valley coalfields but in the present assemblage it is "''''0''['11 associated with Parasaccites (18%) along with a"I"o' U'IH' Cahelliasaccites (11%) and Primuspollenites, thus having a Fig. 3-Sh:lwing [he location of Borehole WM- 14 (DGM. Nagpul) 96 THE PALAEOBOTANIST NAME OF GENERA BREVITRILETES TIWARIASPORIS • VERRUCOSISPORITES • • DENSIPOLLENITES • CAHENIASACCITES • - • CRUCISACCITES PARASACCITES • - VIRKKIPOLLENITES • POTONIEISPORITES • ILLINITES • FALCISPORITES