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gneiss, brings it into nearer comparison with the Bijawar (transition) series of the Peninsula which rests in like manner on the south margin of the Bundelkhand gneiss. The characteristic breccias of the Bijawar area and the Narbada valley are not represented in the Neemuch sections, but the absence of such peculiar rocks may not signify, so the wide correlation may be provisionally accepted. The other pre-Vindhyan formation, the Gwalior series, resting on the northern margin of the Bundelkhand gneiss and not specifically identifiable with the Bijawars but having some points of affinity with the lower-Vindhyan and the Kadapa, was found characteristically represented in the Arvali area at Hindown, and subsequently Mr. Hacket made it out to be a member of his Arvali series (Rec., XII, p. 24). We thus seem to have in this region, on the north-west border of the Peninsula, an extensive exhibition of a great system of very ancient rocks that occur locally in various parts of the peninsular massif.
We are still however very much in the dark upon the details of the relations and homotaxis of this immense sequence of formations (including the Vindhyans), all having as yet proved azoic. No unconformable break could be more marked than that of the typical lower-Vindhyans and the Bijawars throughout the Son valley; yet here in the Neemuch district we seem to have members of the older series that were originally by petrological characters and stratigraphy placed with the adjoining upper-Vindhyans. Thus there is unlimited room for the discovery of 'mistakes,' than which nothing is more gratifying to the average human being; so the present apparent anomalies of the situation are here broadly indicated to stimulate the ardour of future explorers.
Mr. Hacket's work in Rajputana has been confined to the older rocks, the Arvalis and the Vindhyans, to the west of which, in the more or less desert country of Jesalmer, the existence of fossiliferous limestones has been known for many years. Mr. Blanford made a traverse of that ground in 1876, from Jodhpur to Rohri on the Indus, and noted a succession of jurassic strata more or less corresponding to those described in Cutch, and of course they are also the marine representatives of some of the Gondwána system. They are surmounted by tertiary (nummulitic) limestones and clays. During last season Mr. Oldham was deputed to explore the northern extension of those rocks towards Bikanir. He found that at about 25 miles north of Jesalmer the nummulitic strata sweep round eastwards passing northwards under the desert of Bikanir. But the most interesting of his observations was that the boulder rock of Pokaran, which had previously been taken to be Vindhyan (although recognized as of glacial origin), must really be the Talchir boulder bed, occurring as that bed so constantly does upon a denuded surface of very ancient peninsular rocks, and forming by position the base of the sequence of mesozoic strata occurring at some distance to the west. As the Talchir group forms all over India the base of the Gondwana coal-measures, Mr. Oldham suggested that there was room in the covered ground between the boulder bed and the marine jurassics for a possible occurrence of coal-measures, with coal. The fact of there being a continuous sequence of marine strata on this horizon in the Salt-range is not in favour of the conjecture, but neither does it forbid it. Mr. Oldham was not very sanguine of success, but in view of the great want of coal in that quarter of India the question was worth looking into. This is now being done; and the latest information is not encouraging : in a
letter dated 1st January Mr. Oldham informs me that he has in some places found upper Gondwánas overlapping unconformably on the Talchirs.
Sub-Assistant Kishen Singh has completed the work he has been engaged on for some seasons, to map the upper-Vindhyans of the Chambal Mr. Kishen Singh. basin. The ground was very imperfectly known, from a single traverse made some years ago by Mr. Hacket to fix approximately the northern boundary of the trap of the Malwa plateau. The continuous survey has brought out some unimportant corrections. The sandstone of Jhalra Patan which had been taken to be Rewah sandstone (upper-Vindhyan) is shown by Kishen Singh to pass beneath the shales and limestones that underlie the Kaimur sandstone and is so proved to be lower-Vindhyan. None of the peculiar lower-Vindhyan beds, such as the Tirhowan breccia of the Bundelkhand area, or the porcellanic and trappoid beds of the Son valley, have been observed in Malwa. Kishen Singh has now been transferred to map the boundary of the Deccan trap in the Mandla and Seoni districts.
Mr. La Touche made good progress with his work in the Garo Hills during the
Mr. La Touche.
past season. Although the structural features are not obscure, progress is greatly impeded by the dense vegetation and the scarcity of fossils in the sequence of tertiary rocks above the nummulitic horizon. Mr. La Touche's progress report is published in the current number of the Records.
During this year again Mr. Middlemiss has been alone in the Himalayan region, and he has done excellent work. His genuine enthusiasm and thoroughness are most refreshing, his real aim being, not to make a display, but to understand. The account of his work is given in the current number of the Records; it was fully ready for publication in October last, but had to be deferred for more urgent though less important work. His ingenuous exposition, and illustration from a local instance, of the 'folded flexure' (to use the older and neater term originally given by Professor H. D. Rogers)1 and its attendant 'reversed faulting,' and of their function in the formation of 'true mountains,' will be instructive to many. Mr. Middlemiss' paper describes a very complete geological feature, about 45 miles in length, immediately east of the Ganges and at the edge of the Lower-Himalayan region, just inside the fringing zone of Sub-Himalayan rocks. It is in the main a long ellipse of crystalline schists surrounded by a narrow fringe of newer strata. To mark how backward we still are (malgré nous) even in the superficial knowledge of large tracts of country, it has to be confessed that this description came as a surprise. In previous notices of this region it has been stated that although the Lower Himalaya begin with a great spur of crystalline schists and gneiss reaching to within 7 miles of the Sub-Himalayan zone between the Beas and the Sutlej, the predominance of crystalline rocks in it comes on in eastern Kumaun, on the frontier of Nepal; but we now see those rocks already established in force close to the east of the Ganges and at the very edge of the region.
Mr. Middlemiss now puts us in possession of a more or less detailed description of a third detached section of the Lower Himalaya. This apparent want of system and continuity of work has already been duly explained by the advantage of taking up ground of which fair maps are available, and this only occurs in the purely British
1 Memoirs, Vol. III, pt. 2, pp. 194-5.
districts. But indeed there may be some compensating advantage in these independent studies of adjoining areas, the adjustment of discrepancies being perhaps more likely to give true results than might have been attained in any endeavour to carry out over a large area a scale made out in a part of it. In the present case the discrepancies are considerable, and it will be well to exhibit them in juxtaposition. The first of the sections referred to is that in the Simla area at the west end of the Lower Himalayan region, where there is the widest display of unaltered rocks. The work there was mine (1859-62),1 and it has least claim to consideration, for it made no pretence to be a survey; the map was a poor one, on a small scale, and the observations were made from cursory traverses of the ground in connexion with a more careful study of the Sub-Himalayan zone, which was really the work in hand, the area covered being evidence to the point. The second area, 30 miles east of Simla, was by Mr. Oldham (1883)2 with the new map of Jaunsar. The third area is 30 miles further east, in Garhwal, by Mr. Middlemiss, now published. I have placed the groupings below in parallel columns, indicating any suggested correlations. In the first column I give Stoliczka's conjectured affiliation of the Simla sequence (from his own observation) with that in Spiti.
The chief discrepancy is between the sequences of Simla and Jaunsar, Mr. Oldham asserting provisionally that the rocks in either have no representative in the other (supra, xviii, p. 4). The horizons he does suggest are indicated in the table: that the Bawar represents part of the infra-Krol; that the Deoban limestone is much older than the Krol limestone (they had previously been supposed the same); that the Blaini is newer than the Lower Chakrata (volcanic beds). Mr. Middlemiss refrains from correlations, not even saying whether his massive limestone may be Krol or Deoban, with the apparent notion that all may yet prove to be one and the same. It would be futile to speculate upon identifications that will in due course be settled by actual survey, but there is one theoretical question upon which I wish to offer a reflection. That the Simla section does not represent a conformable sequence, is a statement I should never have disputed under any strict meaning of the term 'conformable'; but among the several inferences I ventured to put forward one had appeared to me on the ground as very remarkable-the parallelism of stratification between the newest and the oldest formations. The most striking instance 'Memoirs, Vol. III, pt. 2.
* Records, Vol. XVI, p. 193, with subsequent corrections, Vol. XVIII, p. 4.
given was that of the nummulitic with the infra-Krol beds at Subathu, where throughout a considerable synclinal fold a characteristic bottom bed of the Subathu group coincides with the bedding of the underlying slaty shales. The denudation-unconformity here involved is, of course, prodigious; but the agreement in stratification is only the more remarkable, and it is constant at this horizon throughout this zone of extreme contortion to the north-west, and is still preserved, with little disturbance, in the Salt-range. The interpretation I ventured to put upon this fact seemed one of considerable importance in the history of mountain formation that in this zone at least little or none of the contortion peculiar to mountain structure had yet affected the old slates at the beginning of the nummulitic age. It was, and is, inconceivable to me that strata which were originally highly discordant could by any play of subsequent contorting action be brought into parallel contact, even exceptionally, much less throughout a great area. A similar parallelism seemed to me to obtain throughout the Simla section. My successors have treated this suggestion with silent contempt; extreme and wholesale unconformities (meaning of course the original relation) have been freely introduced. I have myself indicated a fact of mountain-growth (Manual, p. 550) that would at least locally reconcile such discrepancies-how complete conformity and utter discordance may grow together side by side-but for actual original contact-sections the inference I drew still seems to me rationally binding, and I would call upon my successors to apply it or refute it.
Mr. Griesbach reached India on the 1st November with the Afghan Boundary
Commission, not much the worse for the two years' journeyings. His notes on Turkistán appeared in the Records for November, and notice of his return traverse from the Oxus to India is published in the current number. The former was a prolongation eastwards on the strike of the formations previously noticed, where they form the Tirband-i-Turkistán, the principal north-western flanking range of the Afghan mountains. The upper cretaceous limestone assumes quite a predominant place, resting unconformably on the older jurassic and triassic strata, which only appear where exposed in the axes of denuded anticlinals. The lower flanking hills expose a great thickness of tertiary strata dipping at high angles beneath the deposits forming the plains of Turkistán. In connexion with the latter Mr. Griesbach notices an apparent continuation of the same elevatory action now going on in the plains south of the Oxus, attributed to a flexure in process of protrusion by lateral pressure. The evidence for the fact itself, as thus explicable, is only indirect, and perhaps needs confirmation by actual levelling. At the eastern end of the Tirband range better sections were obtained of the older rocks, in the lower members of which some extensive coal-measures were discovered; and Mr. Griesbach reports the important fact that the bottom conglomeratic beds of the series (presumed to be Talchirs) as observed near Herat are found in the Bamian sections associated with beds containing marine carboniferous fossils, thus giving further evidence, were any more needed, of the carboniferous age of the early Gondwána deposits.
For those on the look out from the Himalayan side Mr. Griesbach's notes of his traverse from Turkistán to India seem a little surprising, though perhaps his previous sections of the western prolongation of the Hindu Kush should have suggested the event. He crossed the Hindu Kush by the Chahárdar pass, north-west of
Ghorband, where the range is represented as in full force, but on the whole section up to Peshawar he found no rock that he took to be older than carboniferous. There were in the axis of the ranges immense intrusions of the syenitic granite, already noticed far to the south and west, and with it a considerable exhibition of metamorphosed rocks, but these were all taken to be carboniferous or newer. It is noteworthy, as consistent with the rest, that the axes of disturbance maintained the predominant east-west direction throughout, even where the Hindu Kush of the maps trends north-eastwards.
The Himalayan point of view mentioned above will be best illustrated by a notice of the contemporaneous observations made by Dr. G. M. Giles in the country beyond Gilgit. On the Himalayan side, it will be seen from Mr. Lydekker's map of the Kashmir territories (Memoirs, Vol. XXII), that the whole of the north-western quarter (Gilgit, Astor, and Baltistan) is a geological waste, a few patches of jura-trias, carboniferous, and silurian formations isolated upon a great expanse of crystalline metamorphic rocks which, though probably including some converted paleozoics, were taken to be largely made up of older (?archæan) gneiss, the continuation of that forming the Ladak axis. Dr. Giles does not pretend to be a geologist, but he made some excellent observations of the physical features of the ground traversed, which included a very large area, from the Pamir through Wakhan and eastern Badakshan (across the Hindu Kush, at its supposed roots), and back through Chitral and Yassin. From the very poor specimens brought back by Dr. Giles it would be inferred that the whole of that large area presented only an extension of the conditions known in Baltistan: no trace of a fossiliferous rock was seen, crystalline and schistose rocks greatly preponderated, with only a few less altered slaty specimens. Dr. Giles further observed that throughout the greater part of the area, the eastern and central, an east-west strike was very constant; while on the west side, i.e., on what is represented as the strike of the Hindu Kush, the prevailing strike of the rocks was north-south, though often irregular. Geologists will understand how indefinite must be the inferences from such data, but there seems at least a distinct contrast brought out, where some at least looked for a tie. There remains about 100 miles of unknown ground (Kafiristan) between the nearest parts (Charikar and Chitral) of the areas under notice, but the notion of structural (axial) continuity seems altered: as if the relation of the Perso-Afghan system to the great (?) archæan massif of the Pamir was quite different from that of the Himalayan system to the same, the latter being direct (axial) and the former only secondary (fringing); so that the only structural continuity between the two systems is to be found in the narrow stratigraphical isthmus (or strait), in the centre of which stands Attock on the Indus.
Geology will certainly be the chief loser by the indefinite postponement of the
The Llhassa Mission.
proposed Mission to Llhassa. It had been settled that Mr. Oldham was to have gone as geologist, and I have no doubt
he would have made the best use of his opportunities.
Publications.-There was no issue of the Memoirs during the present year. These are only occasional publications; when some special area, involving several seasons' field work, happens to be completed, or some other work of greater length than can conveniently find place in the quarterly Records. A Memoir on the Chhindwara coalfields is now in the press, and Mr. Griesbach's Himalayan Memoir is well in hand.