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in a gentle synclinal along the valley of the Kamalada, with the gneiss as the uppermost member of the series! Those readers who have followed the history of the geology of the Chor mountain will see that we have here exactly the same apparently unsolvable problem that at first proved too much for every one in the case of the Chor. It is true that we now have a partial answer in the case of that mountain, inasmuch as it is certain that its material has been in a condition of aqueo-igneous fusion sufficient to allow of its tearing off fragments of the neighbouring rocks among which it was intruded, and enclosing them in its substance, but we cannot assume the same explanation here until the same proofs in this case of included fragments, and the evidence of the microscope have been brought to bear on the question in this locality. Later on, I shall have to mention Kalogarhi mountain in British Garhwal, an isolated peak, also composed of this gneissose rock, and presenting in its neighbouring relations very much the same features. It also, at first, appears to lie in a synclinal, as a capping on the summit of the hill, and in many ways it may be looked upon as a miniature Chor. The explanation of the Kalogarhi rock rests, however, on the proved great age of the schistose strata amongst which it lies: although the schists there have the appearance of being the highest of the neighbouring formations. The proving of this involved much labour and time, neither of which could be given to the Rama Serai section on account of my rapid
Returning to the section down stream in the Banale river, we have the spur from the main ridge running towards Shishalu and dividing the upper branches of the Banale river, showing distinctly the various outcrops of the schists and the limestone as they appear to dip in towards the mountain and at a much higher angle than met with heretofore. The bed of limestone is not by any means thick, but between Shishalu and the ridge running east from Saulda peak, and between the last point and Palaita the thickness varies very much, becoming less as the outcrop is traced south by the last-named places to the Jumna. Beyond Palaita I could not see where it went to, but its line of strike from that place would carry it very well to join up with the Deoban limestone of Jaunsar near Lauri.
At Bigrar village (not marked on the map), which is half a mile above Deltu, the limestone beds have come to an end, and we come upon Shaly slates. grey shaly slate dipping about 20° north-west. After a short thickness of these there comes beneath them a thin bed (not more than 60 feet) of a dark, micaceous, gneissose rock, finely foliated, and of Another gneissose rock. very different aspect to that on the other side of the Saulda ridge. Of this, and other rocks collected during last season, I hope to make a thorough microscopical examination later on; I can now only say that the quartz is present in large quantities, showing the polysynthetic structure so common in gneiss of other parts of the Himalaya examined by Colonel McMahon. No fluid or other cavities can be seen. The felspar is not so abundant as in a typical granite or gneiss, occurring in less quantity than the quartz; it is decomposed almost beyond recognition. Biotite is fairly represented, and there are a few needles of apatite. Whether the rock is an intrusion, or is metamorphosed in situ, is a question I cannot answer
See Records, Vol. XVI, p. 144.
by any direct evidence. Its regular appearance bedded with the other rocks, and its lateral continuity between the stream and the ridge east of Saulda peak along the strike of the rocks, favours the idea of its being a true gneiss, and not a foliated granite; but, on the other hand, the selective metamorphism required to pick out a bed 60 feet thick and make it a gneiss without altering the surrounding rocks relatively at all, seems incredible.
Quartzites and slightly
Between Kanal and Goldar there come beneath this gneissose bed olive-grey quartzites, blue-grey quartzites, and finally slightly schistose slates, all dipping about north-north-west 50°. From Goldar to Jeshtar, and the ridge east of Saulda Peak I re-crossed over the same set of beds. I then descended towards Cheli; the latter part of the descent being entirely upon the slightly schistose slates, which in some cases became very micaceous and soft.
Having crossed the Jumna at Barkot I took up the stream south-south-east from there, and for the first mile I passed over much the same Gneissose granite. kind of rocks, but not very schistose, the dip being irregular. Then came fragments of a granitic rock for about half a mile, though the nature of the country prevented any good exposures being seen. It appeared to be a rock related to the gneissose bed last described, but the foliation was not much marked. Then came rather gritty, close, blue-grey slates, dipping 60° west-south-west. On getting to the pass, about 6 miles from Barkot, which pass is north-52°-east from Bouk station, looking south into the tributary of the Bhagirati river there is still the gritty slate dipping 20° west-north-west. Beyond the pass, in an easterly direction, the ridge rises into a mass of the granitic rock, which also keeps to the higher parts of the spurs running down into the tributary of the Bhagirati river as far as a point east-south-east from Bouk station, where there is a sharp line of junction (probably a fault) running north-east between it and a massive blue-grey limestone. The lower parts of the same spurs are composed of the slaty rock, and some few gritty beds, with a general dip 30° or 40° west-north-west near the pass. The dip gradually veers round more to the west, and finally becomes south of west as Darng is approached. The limestone, which resembles the Deoban, only crosses the stream bed a little way, and is then cut off in another direction by a fault striking southeast almost in a direct line between Bouk station and Darng.
Returning to the granitic rock, the quartz in it is abundant, in large grains, and with no polysynthetic structure. Numerous strings of liquid cavities, and dust of opacite ramify through the quartz grains. The felspar is in the same condition as that of the Banale river gneiss. The mica is biotite as before, sometimes dark brown, but often quite black, and opaque in thin slices. The granitic mass in its upper parts seemed to change somewhat in nature and take on a rather more dioritic appearance. I was disposed at the time to think that it was indeed a gradual change in the minerals, but I had not time to stay and work all round the mountain. Speci mens from the top of the ridge due east from Bouk station are almost certainly a diorite though the rock has not been sliced yet.
Continuing down the tributary of the Bhagirati near Gewla and Darng we find the same gritty slates and quartzites of dull grey colour dipping towards the southsouth-west, at 45°.
Purple and green shivery states and quartzites.
It is near where the stream enters the Bhagirati that a change takes place, and the dull coloured slates and grits give way to a set of shivery slates of purple and green colours. These weather into a violet, or pale green powdery rock, which forms steep taluses on the river banks. There are some quartzite beds incorporated with them, and a few conglomerates near Upu (sheet 66). How this change sets in I did not observe, as the structure of the lower parts of the valley is much obscured by recent gravels extending up to a height of 300 feet or more on each side of the Bhagirati, and through which it has cut its course. The general dip is south-west or north-east, apparently rolling about a good deal, first in one direction and then in the other. The appearance of the beds, the nature of the conglomerate, their colouring, and especially the way they weather, forcibly reminded me of the beds seen on the road to Chakrata, near Kalsi, in Jaunsar. The whole of the fair valley of the Bhagirati down to Tiri, and probably beyond, is likewise composed as described, the uniformity being due to the recurrence of the same beds by repeated foldings.
At Tiri I left the Bhagirati river and turned east up the Bheting river, making as direct a line for Pauri as possible. As far as Nurni there does not seem to be any material change in the rocks, but looking north across the Bheting towards Kytiba and Kireh trigonometrical stations, a set of thick-bedded quartzites can be detected constituting the rugged sides and summits of those peaks. Half a mile or so north. of Nurni and Koti, the same beds were traced by me running up from Ushunna along the ridge south-east and east towards Maniknath. In their lower part there is a limestone, dark blue, and resembling those already mentioned in this paper. It is only a hundred feet or so in thickness. A mile and a half east of Koti the junction between the slaty beds and the quartzite is seen on the pass leading over into the affluent of the Alaknanda river. Here, too, are some diorite and dioritic ash near the junction, and no limestone. There is also a change in the lower slaty series at this place; they lose the bright tints hitherto possessed and become more like the sombre tinted rocks that we had before entering the Bhagirati; that is to say, they are grey, and slightly schistose. They also have a nearly vertical dip south or southwest. On the left bank of the affluent, some distance above the road, the limestone and the quartzite were traced as far as Kunnali, but below this, on account of the dense vegetation of creepers, &c., nothing more could be seen of them. I should mention that this quartzite is of exactly the same type as the Bawars, a strong clear-grained quartzite, approximately horizontal, and apparently capping the heights and the ridges unconformably. It is evident, however, that having lost touch of the Bawars so long since, no reasonable correlation can be made in this case. The whole of the south-west side of the stream bed east of Chandabadni mountain down to Gar (Gur), is remarkable for the effect that the vertical or nearly vertical dip has had on the carving out of the hill-spurs: they are like a number of sharp pyramids rising one behind the other in very beautiful succession. The rest of the way to Jarkni on the Alaknanda is over the same kind of beds.
From Jarkni I crossed the Alaknanda, and arrived in British Garhwal, where I at once set to work to find a place suitable for commenc ing systematic mapping operations.
It will now be useless, or at least unnecessary, to continue the narrative form of this paper. Instead, I shall endeavour to put in a somewhat brief manner the results of numerous traverses, and counter-traverses, over a geologically compact bit of country, lying north and south between the Sub-Himalayan boundary and the Nyar river, and east and west between the Ganges at Hardwar and Ghungti mountain.
This portion of the Himalaya has proved interesting geologically in two ways. In the first place, it was there that I came unexpectedly upon outliers of nummulitic and mesozoic strata, which I traced, as stated in my previous paper,1 into conjunction with beds of the same age, long ago noticed by Mr. Medlicott as existing in the Tal and Bedasni rivers. In the second place, the remarkable positions which they had assumed with reference to other rocks of the district raised momentous questions in physical geology, very much akin to what have been satisfactorily answered of late years in the Durness-Eriboll district of West Scotland. These for some time proved a stumbling block to me: for, much as the solution of the Highland question tempted me to readily interpret this district by a similar line of reasoning, I felt that no real knowledge would be gained unless I could prove the case here on its own merits alone. This I have been able to do.
The small-scale map (4 inch to the mile) accompanying this paper gives the nearly completed results of my mapping of the ground, whilst the large-scale map (1 inch to the mile) of the north-west corner of that district is the one to which I shall refer for proofs of the interpretation which I shall submit.
In my previous paper I have already indicated the petrological characters which the rocks present. With regard to their chronological order I will at once anticipate what I shall subsequently prove, by giving a table, which differs from what I previously drew up by the relative positions of the Tal (mesozoic) and the massive limestone being interchanged.
Table of formations (in descending order) in W. British Garhwal.
1 A fossiliferous series in the Lower Himalaya of British Garhwal, Rec. G. S. I., Vol. XVIII, pt. 2, 1885.
Mem. G. S. I., pt. 2 Vol. III, p. 69, 1863.
See Prof. Lapworth's "Secret of the Highlands," Geol. Mag., 1883. Also Messrs. Peach and Horne "On the Geology of Durness and Eriboll with special reference to the Highland controversy.” Nature, XXXIII, 1885, p. 558.
Table of formations (in descending order) in W. British Garhwal-contd.
Without perplexing the reader by detailing the array of difficulties which presented themselves to me at different stages of my work, I will at once come to the main difficulty, in the right understanding of which all other minor questions are bound up.
If reference is made to the inch map, the eye will at once grasp the fact that there is a central elongated area composed of the schistose series and which may be called the "Inner formation;" whilst surrounding it on all sides is a zone of all, or some, of the formations from the nummulitics down to the purple slates and volcanic breccia. These may be called the "Outer formations," in contradistinction to the schistose series. Now the belief which is at present so rapidly gaining ground that metamorphic strata are presumably older than unmetamorphosed strata makes one at the first glance assume a strong probability in favour of the inner schistose series being of much greater age than the outer zone of formations. But no sooner has this à priori probability obtained a firm hold of the mind than a rude shock is given to it by the discovery that at every point round the schistose area the Outer formations appear to dip towards and under the schistose series at steep angles (50°-60° generally); whilst the schistose series itself is disposed apparently in the form of an elongated quaquaversal synclinal upon the top of the Outer formations, and culminates in a capping of gneissose rock on the summit of Kalogarhi mountain (locally known as Kalan Danda), the highest point of the neighbourhood.
In other words, the observer after a hasty examination is almost driven to the conclusion that there is an upper metamorphic series lying normally upon the comparatively unmetamorphosed zone of Outer formations (a counterpart of the opinion long held with regard to the strata of the Scotch Highlands).