Comment (1) on the paper, "Quaternary Stratigraphy and Sedimentation of the Indo-Gangetic Plains, HaryanaH by J.L. Thussu, published in Jour. Geo1. Soc. India, v.46 (5), pp.533-544.
A paper on above subject is very welcome, as literature on the Quarternary lithostratigraphy of the extensive piains of Haryana is rather scarce. However, we would like to offer the following comments (Ref. Table I in conjunction):
1. The author has placed Older Fan and Piedmont below the Ambala Older Alluvium (AOA). However, in his N-S section (FigA) these pebble dominated coarse grained deposit simply represents the northern coarse facies conti nuation of AOA and not an older deposit. This sl~tting can be explained as lithofacies variation from rudaceous facies in the north near the Siwalik hills to sand-silt-clay facies towards south in the central alluvial plain. Similar setting of rudaceous facies
in
contiguous Ganga plain ofULtar Pradesh is recorded all along the Siwalik hills by surface and sub-surface data and is mapped as the proximal mega-fan facies constituting the northern part of Varanasi Older AlluviumNOA (Kumar, 1994). This rudaceous facies is superimposed by a younger Alluvial Fan Deposit, variously named as Ramganga Alluvial Fan (Sukla and Sukla, 1994), Kallaunia Alluvial Fan (Kumar and Kotiyal, 1994) and Phika Alluvial Fan (Hari Singh & Jain, 1993) in different parts of the piedmont zone. It consists of boulders, cobbles and pebbles near base of the Siwalik hills and sand-silt-clay away from the hills. On the basis of presence of brown earthen pottery pieces, it has been assigned Holocene age. This younger Alluvial Fan deposit has not been separated from the Older Alluvium by the author.Age
Holocene
Table I. Lithostratigraphic sucession in Tr,do-Gangetic Plain.
Uttar Pradesh (Kumar, 1992 and 1994)
Newer Alluvium
Recent Alluvium Terrace Alluvium
Alluvial Fan Deposit
NW Haryana (Saini & Anand, 1995)
Haryana (Thussu, t 995) Newer Alluvium & Aeolian Sediments Newer Aeolian Deposit Younger Alluviulfl
Ambala Older Alluvium
Disconf ormity
-Older Aeolian Deposit Older Fan & Piedmont
Mid. to Upper VDranasi Older Alluvium Varanasi Older
Al-Pleistocene luvium
Disconformity Fault
-Late Phocene Banda Older AHuvium & Upper Siwalik Banda Older Alluvium Mid. Pleist. Siwalik...:;
to early Mid to
Pleistocene Mid Mioe.
... Unconformity •
-Mid Siwalik, Bundeikhand Gneiss etc. Tertiary, Nagaur Group, Marwar Super Group Delhi Super Group
DISCUSSION 231
2. Ambala Older Alluvium of the author (term used for the first time) for which the author has incorrectly assigned Holocene age (Table I; p.536) has been mapped throughout the Ganga basin as Varansi Older Alluvium of Mid to Upper Pleistocene age (Kumar, 1992, 1993, 1994 and 1995; Pandey etal., 1991, Khan et at., 1992; Awasthi and Srivastava, ] 993) on account of its stratigraphic position above the upper SiwaliklBanda Older Alluvium (Late Pliocene to early Mid. Pleistocene) and below the Newer Alluvium (Holocene). VOA
is found to be made up of rudaceous facies in the northern parts and sand-silt-clay facies in the southern part of Indo-gangetic plain. The silt-clays are yellowish and ca1cretised while sands are grey and brown.
3. The author cursorily interprets an important sequence of "gravel-red clays" merely as defining the unconformity between Ambala Older Alluvium and the basement (p. 538). In southern part of Sirsa district, the brown gravel and red-white clay sediments are 45 m (Dudiyanwali) to 1115 m (Ellenabad) thick and constitute a stratigraphically significant sequence different from the overlying yellowish silt-clay and grey-brown sand sequence of Ambala Older AlluviumNaranasi Older Alluvium. It consists of sub-angular, reddish sandstone gravels which are similar to the Nagaur Group rocks and thus indicate a peninsular provenance. Such sequence in Ganga Basin, 4as been designated as Banda Older Alluvium (Pandey et at. 1991; Khan et ai. 1992; Awasthi and Srivastava, 1993) and found to be coeval with the upper Siwalik (Kumar, 1993).
4. Ambala Older Alluvium discussed in the bore hole sequence of Sirsa, Hissar and Jamalpur (p.538) have also been included in the Younger Alluvium on page 539 without giving proper explanation. Author states that Younger Alluvium has b.een deposited over the Central Alluvial Plain (CAP) by the Ghaggar river (p.539).
In NW Hary ana Ghagghar is an entreched river having a 4 to 10m deep channel with 50 to 100 m wide palaeobanks. Its Recent Alluvium deposit is confined within the channel palaeobanks in form of few meter thick bars of micaceous sand. The sediments outside the palaeobanks are characterised by yellowish calcretised silt-clay which are typical ofVOA and are not related with the Ghaggar. Therefore, mere presence of grey sand in Sirsa and Hissar boreholes outside the ghaggar palaeobanks is no criteria to include these sediments in younger Alluvium. It is important to mention that grey sediments are also commonly found in VOA throughout the Indo-gangetic plain and occur even at depth greater than 100 m. Though mineralogy of the grey sands ofVaranasi Older Alluvim and Ghagghar river is same but it only suggests a common Himalayan source (Hari Singh, 1991) while the field setting clearly differentiate them as two sequences of different ages.
5. Aeolian deposits of diverse stability, orientation and morphology form an impor-tant and integral part of the late Quaternary stratigraphy especialJy for their palaeoclimatic significance. These deposits are not described by the author even though listed in his Table
I.
6. It has been stated that Ghaggar was active ever since Siwaliks were uplifted (p. 539). This will make the river atleast of Middle Pleistocene age. Ghagghar river, alongwith the Ganga and the Yamuna river formed during Holocene at the beginning of the present interglacial period (Kumar, 1993). Thi is exemplified by their dissection of the VOA throughout their course and even the Newer Al1uvial Fan deposit.
7. On page 539, the author interprets that in Sonepat-Palwa] Sector Yamuna has no well developed flood plain and has remained fixed in
its
position. In this regard, we wish to record that in this area Yamuna has well developed older flood plain on both sidesrepresented by Tl terrace. The width of Tl along Delhi--Sahadra-Ghaziabad is around 15 km while further south (east of Ballabgarh), along Manjhauli-Dhankaur the width is 10 km. It is well known that entire east Delhi is situated on Tl terrace (Saini et al. 1995). Further, Author's finding on the thickness of the grey sand of Yamuna i.e. Younger Alluvium appears highly exaggerated. Like Ganga river, in Yamuna also the grey sand (Younger Alluvium) is confined within its well defined palaeobanks mainly as Terrace Alluvium. Only 2. to 5 m of this grey sand is exposed in the terrace sections. However, boreholes drilled on the terrace record the presence of yellowish hard ca1cretised silt-clay at IOta 30 m depth below grey sand between Delhi and Pal wal. This suggests that thickness of Younger Alluvium can not be more than 30 m.
8(a). On page 536 the author describes pediplain features east of Faridabad, around Delhi and South of Rohtak. These areas have a thick column of Quaternary sediments. According to the defination of pediplain (Haffman, 1988, p.373 and Thornbury, 1967, p.191) these canriot be classified as pedip/ain. Moreover, using same criterion, entire southern part of Central Alluvial Plain of the author has to be classified as pediplain.
(b). In the same paragraph, source of the overlying sediments (Quaternary) is mentioned to be the southern landmass. The Quaternary sediments around Faridabad consist of horizontally bedded yellowish silt-clay, kankar, grey and brown sand which as already pointed out, is the typical1ithology of Varanasi Older Alluvium of Himalayan source and not peninsular source. This is also supported by mineralogical composition of sands characterised by transparent quartz, hornblende muscovite, gamet, kyanite, sillimanite, biotite, chlorite, orthopyroxene, tourmaline and rutile and are similar to the Recent sediments of Yamuna being transported from the Himalayas.
9. The author had divided the Central Alluvial Plain in a southern part having abundance of clay and a northern part having alternate sand and clay (p. 537), but the same has not been reflected in the geological sections in Fig. 4 and 5, which show the dominance of clay in north and south. Moreover, in the southern part, the author describes the Sirsa and Zalenia borehol~s as consisting of alternate sand and clay layers and the Jamalpur borehole consisting of fine to medium sand with thin clay. This contradicts the very basis of classifying the Central Alluvial Plain.
10. Term pedogenic kankar is used indiscriminately throughout the text without substantiation. However, on page 549, non-pedogenic kankar of fluvial origin is described to occur between 2 and 100 m depths around Mayar, Tosham and Dadri. The near surface kankar around Dadri and Tosham occurs as isolated, lensoidal bed of 0.50 to 2 m thickness having profuse gastropod shells. The fauna and flora of these kankars have been found to be of lacustrine origin (Bhatia and Singh, 1988). In buried kankar a few gastropod shells have been reported (Mayar borehole) which is not a sufficient basis to classify the kankar as non-pedogenic unless backed by macromorphological and microscopic characters like profile characteristics, displasive or replacive texture and stable isotopic composition.
11. In either the map or the sections, the distribution or demacation of proposed lithostratigraphic units is shown which makes it difficult for the reader to understand their lateral or vertical extent.
DISCUSSION
12. The basis of sea level flutuation (p. 541) is not given.
957/Type - IV
N.H. -4, N.!. T.
Faridabad - 121 001
References
233
HARI SINGH SAINI S.A.I. MUITABA
AWASTHI, S.K. and SRIVASTAVA, A.B. (1993). Quaternary geology and geomorphology of parts of Ganga basin in Lucknow, Kanpur, Unnao and Rai Bareilly districts, Uttar Pradesh. Records Geol. Surv. Ind., v.l26, pt.8, pp.64-67.
BHATIA, S.B. and SINGH, N. (1988). Middle Holocene palaeo- climatic and palaeo-environmental events in southern Haryana. Proc. India, Nat. Sci. Acad., v.54 A(4), pp.574-584.
HARI SINGH (1991). Mineralogy and morphometry of some Recent Aeolian and Alluvial sediments of Haryana. Records Geol. Surv. Ind., v.129, pt.8, pp.7-8.
HARl SINGH and JAIN, V.K. (1992). Quaternary geology and geomorpholoy of the Moradabad-Jhirna area of Ganga basin in parts of Nainital, Bijnor and Moradabad districts, Uttar Pradesh. Records Geol. Surv. Ind., v.125, pt.8, pp.58-60.
HAFFMAN, M. (1988). Dictionary of Geology, Goy Lsaab (first Indian Edition).
KHAN, E.A., PANDEY, B.N., KHAN, A.v. and BISARIA, RK. (1992). Regional Quaternary geology and geomor-phology of Quadrangle map. Records Geol. Surv. Ind., vJ25, pt.8, pp.55-56.
KUMAR, G. (1992). Review of work done by Regional Geology Division-II, Op: Uttar Pradesh. Records GeoL Surv. Ind., v.125, pt.8, pp.35-37.
KUMAR, G. (1993). Review of work done by Regional Geology Division-II, Op: Uttar Pradesh. Records Geo\. Surv. Ind., v.126, pt.8, pp.56-58.
KUMAR, G. (1994). Review of work done by project Quaternary Geological mapping Ganga Basin (East). Records Geo!. Surv. Ind., v.127, pt.8, pp.164-166.
KUMAR, R. and KOTlYAL, PL. (1994). Quaternary geology and geomorphology of Pilibhit-Khatima area, Ganga basin in parts of BeraiIly, Nainital and Pilibhit districts, Uttar Pradesh. Records Geo!. Surv. Ind., v.127, pt. 8, pp.177-179.
PANDEY, B.N., KHAN, A.v. and BISARIA, B.K. (1991). Compilation of Quaternary geological and geomorphologi-cal map of Quadrangle sheets 54E, 54F and 54J Uttar Pradesh. Records Geo!. Surv. Ind .. , v.124, pt.l24, pp.5961.
SAINI, H.S., MUITABA, S.A.I. and GUPTA, A.K. (in press). Floods in Delhi - A geomorphological and geological prospective in an urbanised landscape. Int. Seminar on Disaster Environ. Development. Univ. of Delhi, December, 1994.
THORNBURY, W.O. (1969). Principles of Geomorphology. John Wiley and Sons, New York, Second Edition, 594p.
Comment (2)
The author must be complimented for the exhaustive analysis of the borehole data on Haryana Quaternary plains. However, after going through the paper it is evident that the entire depositional model and elucidation put forward is contemplated in isolation. The Haryana Plains are western extension of the V.P. Plains and the lithostratigraphy should have been built up in regional perspective. The following significant points for building up the lithostratigraphy of Haryana are put forward:
l. The Quaternary deposits of Haryana are intergral part of the vast 1GB wherein concomitant episodal sedimentation took place under fairly similar regional palaeoclimatic condition.
2. Post Neogene, the 1GB development, its sedimentation pattern, provenance, basinal tectonism reflect similar and uniform depositional pattern from east to west. The author appears to be unaware of the well established account of the Quaternary deposits, its lithostratigraphy in the adjoining U.P. Plains (Kumar, 1992, 1993; Kumar and Singh, 1992 and Kumar et ai. 1995).
3. The initiation of the IGB started as a sequal to the collision of the Indian and the Chinese plates. Initially a narrow trench "foredeep" evolved (Kumar, 1995; Singh, et al. 1995). This narrow basin was the recepient of the fresh water molassic deposits. The bulk of these sediments comprise the Siwalik sequence. Owing to continuing compressional forces and in resonance with Himalayan orogenic and epeirogenic movements (HOM) this foredeep basin kept on trangressing and expanding southwards during Plio-Pleistocene period. The southern limit of the 1GB in U.P. skirts around the Bundelkhand Massif and Vindhayans, while the Aravalli upland defines its southern limit in Haryana. Along the southern fringe of 1GB in V.P. Khan and Das Gupta (1984) recognised a thick continental pediplain deposit comprising alternating dark brown clays and light brown silts with red quartzo-felspathic sands. This unit is fairly well exposed between Allahabad and Agra, in Yamuna, Ken, Betwa and Chambal river sections. Based on the regional continuity, archaeological, palaeontological finds and climatic imprints Kumar et al. (1995) correlate this unit with the Upper Siwalik (Boulder Conglomerate) and have designated it a formational status namely Banda Older Alluvium (BOA).
4. The author's description of thick clay sequence in south Haryana (Fig. 4 and 5) in all likelihood is correlatable to the BOA sediments of V.P. representing continental derivatives from the southern Arava1li litho-assemblage and are not of Himalayan Provenance. This unit is not reflected and separated out in the lithostratigrpahic column (Table I).
5. The lithostratigraphy given in Table I is ambiguous. The Older Fans and Piedmonts (OFP) are basal part of the Ambala Older Alluvium (AOA) sequence. The OFP are shown upto Middle Pleistocene whereas OAO are grouped under Holocene with Younger Al-luvium and aeolian deposits with a disconformity in between. The AOA are coalescing alluvial fans comprising boulder-cobble- pebble fraction in proximity of Himalaya and finer sediments (sand-silt-clay) to its south in the IGB were under fluvial processes laid down as composite channel bar/point bar sand and over bank silt-clay sequence of multiple fin nature. These are corellatable to the Varanasi Older Alluvium (VOA) of U.P. (Kumar et al. 1995). Throughout this sequence extreme facies variations both vertically and laterally pose difficulty in litholog correlation of boreholes.
6. It is also evident from Fig. 4 and 5 that the AOA sediments containing grey sand horizons (derived from Himalayan sources) conceal the older clay units (correlatable to BOA) of south Haryana. The AOA is in turn superimposed by the Holocene Younger Alluvium (YA) and aeolian deposits with distinct disconfonnity between the two.
7. The Yamuna-Ghagghar drainage system are described as active since the Siwalik uplift. This is untenable. Conclusive evidences show that these drainages are superimposed on the AOA-VOA platform and have evolved post Upper Pleistocene-Holocene glaciation (between 12 Ka to 7.5 Ka) . Near vertical bluffs define the palaeobanks of these rivers,
...
DISCUSSION 235
beyond which they have never migrated. Depositional activities of these rivers are docu-mented in their 1-2 level of terraces. The grey sand association in the terrace sequences and the ADA is ascribable to the same Himalayan source.
8. Postulations regarding sedimentation in Jamalpur-Bhiwani- Kamal-Panipat-Jind by Ghagghar and description of grey sand horizons cast and west of Yamuna upto a depth of 200 m are erroneous. These sediments are upper part of AOA and have not been laid down by either Yamuna or Ghagghar rivers of present day. The YA thickness of Yamuna is between 20-25 m (Khorana and Das Gupta, 1988) and much less in Ghagghar.
9. The subsurface beasement under the Quaternary plains of Haryana manifest two prominent sub-surface ridges. The NE-SW Delhi-Hardwar ridge (bound between Mahendragarh-Dehradun fault and Great Boundary Fault) and the Delhl-Sargodha ridge (Srinivasan et al. 1995). Besides there are a number of N-S, NE-S\V and NW-SE oriented fractures extending from Rajasthan which are cut across by E-W cross faults. Basement related tectonism is responsible for occurrence of quaternary sediments below M.S.L. The other factor is the gradual basinal sinking along the Himalayan Foot Hill Fault, where the Quaternary sediments have attained a maximum thickness. Selective sedjmentation in faulted trough are unlikely.
10. The concluding remarks of the author about sectorial sedimentation under high energy to low energy conditions and tectonically controlled sedimentation along earlier lineaments is hypothetical.
175, Deshbandhu Apats., Kalkaji, New Delhi - 110019
References
G. DAS GUPTA
KHORANA, R.K. and DAS GUPTA, G. (1988). Report on Quaternary geology and geomorphological mapping in parts of Ambala and Kurukshetra districts, Haryana. Unpub. GSI reports (FS. 1986-87).
KHAN, E.A. and DAS GUPTA, G. (1984). Report on Quarternary geology and geomorphology of Ghatampur Kalpi area in Kanpur, Humirpur and Jalaun districts of V.P. parts of Ambala and Unpub. GSI report (FS. 1980-81).
KUMAR, G. (1992). Review of work done by Regional Geology Division-II Operation U.P. Rec. GeoI. Surv. India, v.125(8), pp.35-37.
KUMAR, G. (1992). Review of work done by Regional Geology Division-II Operation U.P. Rec. Geol. Surv. India, v.126(8), pp.56-58.
KUMAR, G. and SINGH, G. (1992). Imprints of global tectonic events in the Himalaya. In : Himalayan Orogen and Global Tectonics (Editor: A.K. Sinha) pp.l69-181. Oxford and ISH Publishing Co. Pvt. Ltd .• New Delhi.
KUMAR, G. KHANNA, P.c. and PRASAD, S. (1995). Sequence stratigraphy of Foredeep and evolution of the Indo-Gangetic Plains, lJttar Pradesh. In : Symp. on recent advances in Geological Studies of NW Himalayas and Foredeep, GSI, Lucknow. pp.338-340 (Abstract).
RAVISHANKAR, KUMAR, G. and SINGH, G. (1995). Sequence. stratigraphy and major geological events of the Himalayas. In: Symp. on recent advances in Geological Studies of NW Himalayas and Foredeep, GSI, LuckliOW, pp.1-15 (Invited Paper).
SINGH, LB. (1995). Late Quaternary sedimentation of Ganga Plain Foreland basin. In: Symp. on recent advances in Geological Studies of NW Himalayas and Foredeep, GSI, Lucknow, pp.I-19 (Invited Paper).
SRINIVASAN, S. and KHAR, B.M. (1995). Status of Hydrocarbon Exploration in NW Himalayas and Foredeep-Con-tribution to Stratigraphy and Structure. In: Symp. on recent advances in Geological Studies ofNW Himalayas and Foredeep. GSI. Lucknow, pp.1-20 (Invited Paper).
236
Reply
The author is thankful to Hari Singh Saini and Mujtaba and Gautam Das Gupta for their interest and comments on my paper. A combined reply to their comments is given below. The serial number of the reply pertains to the reply to the comments of Singh and Mujtaba while the number in parenthesis pertains to the comments of Das Gupta.
1 (5). The "Older fans and associated boulder-pebble-grit-clay alternations" has been associated with the river system which has by now been completely obliterated. These older fans are being incised by the later drainage. The stratigraphic position of these fans and piedmont zones below Amhala Older Alluvium (AOA) is justified as the sediments of the fonner, imperceptibly pass into clay-sand association of the AOA. This is depicted in the cross sections and as well as in the text. No newer fans have been superimposed on these fans in parts of Haryana. The younger Alluvial Fan deposits referred as Ramganga Alluvial fans etc. are not developed in parts of Haryana hence the suggestion of their separation from Older Alluvium is out of place.
2 (5). The term Ambala Older Alluvium (AOA) has not been used as a new term in this pa.per. This term has been carried over from Thussu et at. (1989a, and 1992); and Thussu and Chopra (1991).
Varanasi Older Alluvium (yOA) exposed in U .P. neither represents standard stratigraphical name nor a type section of the "Older Alluvium" for whole of the Indogan-getic basin. AOA, however, may be equivalent to VOA both in time and space with lateral variations. Discrepancy in the Table I due to oversight is regretted. The Upper to Middle Pliestocene period in column 1 should have included AOA and Older fans and piedmont zone as well.
3 (4). Banda Older Alluvium (BOA) is exposed in the southern parts ofU.P. and its characteristic features are: (1) presence of andalusite, which otherwise is absent both in Varanasi Older Alluvium (VOA) and Newer Alluvium, and (ii) presence of vertebrate fossils (Kumar, 1992, 1994). As has been clearly mentioned in the text, the (subsurface) geology of the Indogangetic plains in Haryana is not well exposed, due to the absence of deep cnt sections. There is no record of any fossil having been recovered from any of the boreholes at Dudiyanwali and Ellenabad in Haryana. Moreover, Singh and Mujtaba have not stated if they have recorded any index mineral such as andalusite from the so called BOA in Haryana. Detailed study of samples from two deep boreholes (240 m deep) in Hissar by author have not yielded any andalusite mineral. In the absence of these characteristic parameters from any of the horizon in bore hole samples comparison of basal part of AOA with BOA would be highly hypothetical and unscientific.
4 (7 & 8). The lithologies discussed on page 538 have not been understood well and conclusion drawn that the whole sequence is described as younger alluvium is wrong. It has been clearly mentioned in the text that some of the boreholes in Hissar and Sirsa area have sandy layers at the top. These top sandy layers represent either the aeolian activity or Younger Alluvium related to Ghagghar river system. There is evidence that grey sand occurs upto 60 m depth in Hissar area.
Ghagghar river alongwith its tributaries is entrenched in the hills only. These are ephemeral rivers and flow almost on the surface level in plains. Bunds which do not represent the actual banks have been built to prevent the overlfow of water. Most of the palaeochannels have been reclaimed for agricultural purposes. It is amply evident during
DISCUSSION 237
rainy season when all the palaeochannels as wel1 as the present day channel are filled with water. There are references indicating that Ghagghar river has shifted its channels in the softer material; Bakliwal and Grover, (1988); Chopra and Thussu (1988); Thussu et al (1989); Thussu and Chopra (1994). The conclusions drawn by Singh and Mujtaba that younger alluvium deposited by Ghagghar river is limited to its present channels are therefore not well founded.
In Jamalpur area rapid changes in the sediments represent alternate fluvial and aeolian regimes. Such rapid changes are known in literature in Holocene times. Moreover such sequence has also been reported from Punjab area in upper 150 m by Garg and Singh (1991, 1992 and 1994) and Sheoprasad et al. (1990) in Haryana.
5. Aeolian deposits have been described though, in lesser details within the descripiton of Younger Alluvium.
6 (7). The principal rivers like Ganga, Yamuna and Brahmaputra have been described as rivers older than Holocene by Krishnan (1960) and Wadia (1978). I quote "The most important fact to be realised regarding drainage is that it is not in a large measure a consequent drainage. There are c1earevidences to show that principal rivers were of an age anterior to them. The Punjab portion of Jhelum, Chenab, Ravi, Beas and Sutlej originated after the uplift of --- Siwalik system and subsequent to the severance --- from the Ganga" (Wadia, 1978). There is evidence that Himalayan rivers are antecedant (Krishnan, 1960). The Ghagghar river has also evolved after the upliftment of the Upper Siwaliks as stated on p. 539 and 541. It is not correct to link the two rivers into a unified drainage system.
7 (8). The migration pattern of Yamuna ri ver is well established; B alachandran (1978) and Pradan, (1979); and Kazim et al. (1988) and Bakliwal and Sharma (1980 and 1988). Shahdara forms the part of Older Plains of Yamuna river and it has shifted towards west where it got contained because of depression caused by reactivation of N-S faults. The description of grey sand upto a depth of 200 m has been misunderstood. The figure 200 m
±
10 m pertains to the depth of boreholes wherein grey sand of Yamuna river is 13 m to 88 m on west bank and 20 m to 56 m on east bank. It is evident that Singh and Mujtaba and Das Gupta are not aware of work done in Haryana. The thickness of Yamuna alluvium given in the paper is based on various drill holes drilled in Yamuna Flood Plains by Central Ground Water Board and other agencies. Moreover the fluvial cycle does not carry only sand, it also carries silt and clay fractions which also form part of deposit of the same river.8. The reading of the referred paragraph clearly indicates that it concerns areas in the vicinity of structural hills, so the surmise of Singh and Mujtaba that entire southern part of Central Alluvial Plain is described as pediplain is wrong. The term pediplain has been used only for the areas skirting the structural hills. Pediplains are formed by coalescence of numerous pediments (Fairbridge, 1968). The whole of Indogangetic plains in Haryana definitely does not fall under this definition. The objections of Singh and Mujtaba are therefore not valid.
9 & 11 (D). The criteria for dividing Central Alluvial Plains into North and South divisions are given on page 537. The same is clearly evident from S-N cross sections depicted in Fig. 4. It may be mentioned that it is not possible to show lithological changes in such a vast area on small scale as the sediments are thin and taper out at short distances. Therefore, the AOA has been demarcated as essentially clay dominated in south and as sand and clay.association in north.
10. The term non-pedogenic kankar has been used wherever necessary and relevant. The kankars occur as lensoid bodies at various levels in the AOA. The kankar beds have thickness of over 30 m. Some kankars do have shells associated with this sequence. I have repeatedly pointed out that the sediments indicates quiet depos-ition with intermitent prolonged periods of arid conditions. In fact these represent deposits in cut-off meander loop, palaeochannels, and back swamp areas.
12. The sea level fluctuation is a generally known fact, corroborated by nearly all the literature on deglaciations and sea level changes. (Fairbridge,1961; White, 1987).
13 (2). The views expressed seem to be without any basis. Most of the references cited in the paper are pertinent to the work in Haryana. Kumar et al. (1992,1994) have not been referred as no correlation was attempted with U.P.
The references of 1995 post-dates the present paper. However, it is necessary to point out that the lithological correlations with BOA ofU.P. is incorrect, hypothetical and without any basis.
The following is reply for Das Gupta's comments not covered above:
3. Das Gupta's comment regarding deposition of BOA are welcome. Unfortunately these are irrelevant to the paper under discussion.
9. Sudden absence of these rocks, infact forms the basis of this paper. Unfortunately Das Gupta has not understood it well. As has been stated (in pp.539-540) that basement represented by rocks of Delhi Supergroup has been encountered in the southern fringe at depths upto 7.87 m~ thereafter (basement) has not been encountered within 600 m upto Bhatinda (Rao, 1973). Even in Delhi-Hardwar ridge borehole failed to encounter basement at Mohand upto a depth of 5264 m (Rao~ 1973) and Karunakaran and Rao (1979). As such no mention of subsurface ridges W8.8 made in the paper as depth of both these ridges far exceeds the limits of borehole sunk. Although the reference of 1995 outdates this paper, it is necessary for Das Gupta to know that Srinivasan & Khar (1995) state that "the Delhi Aravalli trend can now be seen being obliquely transverse to the basinal strike and therefore, unrelated to primary structuring of the sediment floor". this corroborates with the view expressed by the author regarding existance of E-W faults in the Indogangetic basin in Haryana. Also please refer to Karunakaran & Rao (1979).
10. There is evidence that sedimentation in Indogangetic basin in controlled by tectonic processes. The author is unable to find the basis of Das Gupta's comment. Sedimentation in the Indogangetic basin has been stated to have been controlled by tectonic proces.ses along earlier lineaments in the basement. Sectorial sedimentation under low and high energy conditons has not been stated. The sunnise ofDas Gupta is purely hypothetical and without basis.
383, Sector 21 B
Faridabad -121 001 Haryal1tl
References
J.L. THU$SU
BALACHANDRAN, V. (1978). Report on geological and geomorphological mapping and sedimentological studies in Yamuna basin, Kamal and Kurukshetrn. Un Pub. Report, Geol. Surv. India.
DISCUSSION 239
BALACHANDRA, V. and PRADAN. P.K. (1979). Report on geological and geomorphological mapping in parts of Yamuna Basin, Shahampur and Muzaffamagar, district V.P. and parts of Kamal, and Sonepath, Haryana, Un Pub. Report. Geol. Surv. India.
BAKLIWAL, P.C. and SHARMA, S.B. (1980). On the migration of Yamuna river; Jour. GeoL Soc. India, v.22, pp.461-463.
BAKLIWAL, P.C. and GROVER, A.K. (19B8). Signatures and migration of Saraswati River in Thar desert, Western India, Rec. Geol. Surv. India, v.116, pt.3-8, pp.77-86.
CHOPRA, S. and THUSU, lL. (1988). Anote on the Avulsion of Ghagghar river in the Alluvial Plains of Punjab and Haryana Northwest, India. Jour. I.S.R.S. v.2, pp.46-47.
FAIRBRIDGE, R.W. (1961). Eustatic changes in sea level, in "Physics and Chemistry of the Earth". v.4, Pergamon Press.
GARG, RAM LAL and SINGH JOOINDER (1991). Systematic Quaternary geological and geomorphological mapping in Sangrur and adjacent parts of Patiala and Faridkot districts, Punjab; Rec. Geol. Surv. India, v.124, pt.8.
GARG, RAM LAL and SINGH JOGINDER (1992). Systematic Quaternary geological and geomorphological mapping in parts of Bhatindra, Faridkot, Ferozpur and Sangrur districts, Punjab; Rec. Geol. Surv. India, v.125, pt.8.
GARG, RAM LAL and SINGH JOOINDER (1993). Quaternary geology and geomorphology of parts of Faridkot and Firozepur districts, Punjab; Rec. GeoL Surv. India, v.126, pt.8.
GARG and RAM LAL (1994). Compilation of Quadrangle 53 B. Rec. Geol. Surv. India, v.127, pt.8.
KRISHNAN, M.S. (1960). Geology of India & Burma, Higginbothams Pvt. Ltd. Madras.
KUMAR, G. (1992). Review of the work done by Regional Geology Division II, Op. Uttar Pradesh. Rec. Geol. Surv. India, v.125. pt.8.
KUMAR. G. (1994). Review of the work done by Project Quaternary Geological mapping, Ganga Basin (East). Rec. Geol. Surv. India, v.127, pt,8.
RAMACHANDRA RAO, M.B. (1973). The subsurface geology of the Indogangetic plains, Jour. Geol. Soc. India, v.14, pp.217-242.
THUSSU, J.L.. GUPTA. G.D., GADHOKE, S.K. and KUMAR, B. (1989). Systematic Quaternary geology and geomor-phological mapping in Kamal, Kurukshetra and Ambala districts, Haryana; Rec. Geol. Surv. India, v.122, pt.8.
THUSSU, J.L., CHOPRA, S. and TVAGI, R.B. (1989). Compilation of geological maps covering parts of Hissar, Jind, Ambala, Kamal and Kurukshetra districts, Haryana; Rec. Geol. Surv. India, v.l22, pt.8.
THUSSU, lL. and CHOPRA, S. (1991). Compilation of quadrangle maps of Haryana, Rec. Geol. Surv. India. v.I24, pt.8.
THUSSU, J.L., CHOPRA. S. and KAZIM. M.K. (1992). Compilation of Quaternary £eological maps covering parts of Haryana State; Rec. Geo!. Surv. India, v.125, pt.8.
THUSSU, J.L. (1993). Quaternary geology and geomorphological mapping in H aryan a. Rec. Geo!. Surv. India, v.126, pt.8.
THUSSU, J.L., CHOPRA, S., DHONDlYAL, IN. and KAZIM, M.K. (1993). Compilation of quadrangle geological maps covering parts of Haryana State. Rec. Geol. Surv. India, v.126, pt.8.
THUSSU. lL. and CHOPRA, S. (1994). Channel migration and phenomenon of Terminal Fan Formation in some of the major streams of Ghagghar river basin of Haryana, NW India. Indian Minerals, vA8 (4), p.265-272.
FAlRBRiDGE, R.w. (1968). Encyclopedia of Geomorphology of Earth Science series. v.3, Edited by Fairbridge, Rhodes, W.Reinold Book Corporation, London, New York.
WADlA, D.N. (1978). Geology of India. Tata-Mc Graw Hill Publishing Co. New Delhi (IV Edition), pp.26-389.
