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Coal. 52. In May, 1936, the Director of Agriculture in the North-West Frontier Province raised the question as to whether the workings North-West Frontier

from which the coal then being won from the Province and Punjab Punjab side of the Surghar range in the Mianwali boundary.

district of the Punjab had penetrated beneath the crest of the boundary ridge to the Kohat district of the NorthWest Frontier Province. His Excellency the Governor of the latter Province approved the suggestion that Dr. A. L. Coulson should be deputed to investigate this matter and also advise on the possibilities of the coal of the Surghar range being worked from the Kohat side.

It was not possible for this investigation to take place in the field season 1935-36 ; but in the field season 1936-37, when it was found necessary for Mr. E. R. Gee to visit the salt mines at Khewra and Kalabagh, advantage was taken of this opportunity for Dr. Coulson and Mr. Gee to pay a joint visit to the Makarwal Colliery area in February, 1937.

In his report to the Government of the Frontier Province, following Mr. Gee's previous work, Dr. Coulson notes that the Makarwal coal is basal Eocene (Lower Ranikot) in age. A dark red, pisolitic hematite shale is sometimes developed at the expense of the coal and there is then a slightly irregular junction between the Cretaceous sandstones below and the sandstones of the basal Eocene Makarwal coal stage.

According to Mr. Gee, the general geological structure of the Surghar range is that of a fold-faulted anticline, the axis of which runs north and south to the east of the crest of the range. Generally the eastern limb of the anticline either so faulted or has been so eroded away that little coal can be extracted. The western limb forms the main range and the coal seam dips at fair angles into the range. The anticline pitches south beyond Lamshiwal towards the Mitha Khatak gorge.

Dr. Coulson with Mr. Gee concluded as a result of their joint observations that none of the coal won from the Punjab side of the Surghar range had in fact been derived from workings extending into the Frontier Province. The very considerable amount of overburden that will be met as the present adits are driven further west, and the soft nature of the Tertiary coal, will make the extraction of the latter a matter for considerable mining skill. Accordingly

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the hope of the Frontier Province Government that coal may be won as the present workings progress under the provincial boundary must be regarded as not likely to be realised. However, if workings are made nearer the Baroch gorge, these will not have to go so far westwards before they are under the crest, but here again the amount of overburden is very large.

Dr. Coulson and Mr. Gee concluded that it would not be practicable to extract the westward continuation of the coal that is at present being worked in the Punjab, by means of workings cominencing in the Kohat district. It would be necessary, according to Mr. Gee's calculations, to sink a shaft 1,500-1,600 feet through the overlying Nummulitic rocks in order to meet this possible westward continuation of the Makarwal coal seam. Apart from this, the topographical features of the Kohat area seem to preclude such an attempt.

Dr. Coulson and Mr. Gee noted that coal does in fact crop out in the Kohat district to the north of the Baroch gorge. Mr. R. R. Simpson had previously noted a 2 feet 1 inch seam of coal and 10 inches of coaly shale, though his map? differs from the present oneinch sheet 38 P/1 in the position of the provincial boundary. Simpson states that this seam thins rapidly to 9 inches as it is traced northward and that near Sheikh Nikka the coal is frequently absent and never exceeds 8 inches in thickness.

In his report, however, Dr. Coulson recommends that it certainly seems worth while thoroughly testing and proving the area between the Baroch and Sheikh Nikka. The total cost of proving this area to just beyond point 2,997 feet should not exceed a few thousands of rupees. He recommends that this should be done by means of two drifts and possibly a shaft. One drift could be driven northwards along the strike from where Simpson collected his sample, this being entirely within the Frontier Province; the second could be driven almost horizontally westwards under hill 2,997 feet from the Punjab side, commencing low down in the belemnite beds. Alternatively a vertical shaft could be sunk, or a horizontal adit driven eastwards at a lower level, through the relatively soft Ranikot sandstones of the Makarwal coal stage to the west of hill 2,997 feet.

If coal be proved in this area, then it would probably be best mined by means of easterly horizontal drifts and then hauled by an aerial ropeway over the shoulder of the ridge and thence down to Malla Khel. The Baroch has a perennial supply of good water and can easily be dammed-but no track lines could be laid up the gorge from Malla Khel to the coal outcrop.

1 Rec. Geol. Surv. Ind., XXXI, Pt. 1, P1, 2, (1904).

Dr. Coulson noted that if an area of only 0.2 square miles could be proved, then assuming that the seam dips at 45°, that the coal has a specific gravity of 1.3 averaging 27.5 cubic feet to the ton and that half the coal can be extracted, then for every foot thickness of the seam the amount of coal that can be won is about 143,000 tons. If this were sold at a pit-head price of Rs. 6 per ton, there should be ample profit to the lessees.

Dr, Coulson also visited the Chichali Pass area to the north-east of the Baroch area with a view to ascertaining whether or not the horizon of the Makarwal coal stage passed into the Frontier Province in this region. He concluded that there was not much chance of workable coal being found in the salient of the Frontier Province south of Kurd. He adds that a contractor of Kalabagh had applied for a mining lease of the area between Kutki (32° 59' : 71° 21') and the Chichali Pass north of Kotki (33° 0': 71° 24'). His efforts prior to Dr. Coulson's visit had been chiefly concerned with the coal of the Jurassic variegated beds that occurs one mile north-west of Chapri and also in the bend of the Chichali stream south-west of Kotki. This coal occurs as a number of thin seams of very poor quality. Dr. Coulson says that the chances of

that the chances of coal being worked here economically may be stated as negligible. This Jurassic coal also extends into the southward salient of the Frontier Province from Kurd, but again has no economic value. The same applicant has also examined the Tertiary coal of the Makarwal stage within the Chichali Pass region, but Dr. Coulson's remarks regarding the improbability of workable coal being found below Kurd in the Frontier Province are equally applicable to the Punjab portion of the outcrop in the Chichali Pass. He also notes on the similarity of the geological structure of this portion of the Trans-Indus Salt Range to that at Makarwal (see also A. B. Wynne, Mem. Geol. Surv. Ind., XVIII, Pt. 2, pp. 256-269, 1880). About 21 miles north-west of Chapri, there is a good anticlinal structure developed in the Cretaceous and Ranikot sandstones. Were coal to be found in reasonable amount in the northern limb of the anticline, there should not be much trouble in working it; but the seam is thin and the coal is apparently not a workable proposition here,

53. In compliance with a request from the Director of Agriculture in the North-West Frontier Province, Dr. A. L. Coulson in Hazara

district. April, 1937, investigated the coal deposits of North-West Frontier the Dore river in the Hazara district of that Province.

Province. In view of the importance of finding workable coal in the Frontier Province, it was thought that though the Dore river coal deposits had been neglected in the past on account of their usual poor, though variable, quality, it might now be possible to utilise them, especially in view of modern developments of low temperature carbonisation.

A short history of the former investigations on the Dore river coal is given in the “Coal” section of the Economic Geology Appendix to Mr. C. S. Middlemiss' memoir on the geology of Hazara and the Black Mountain (Mem. Geol. Surv. Ind., XXVI, pp. 287-290, 1896). Middlemiss regarded the grey limestone underlying the coal as Eocene, which would make the coal younger than the basal Eocene (Lower Ranikot) age assigned to the coal of the Trans-Indus Salt Range at Makarwal. However, Dr. Coulson regards this grey limestone as Cretaceous and the Dore coal as homotaxial with the Salt Range coal.

After discussing the geology of the area and noting on the various outcrops of coal visited by him, Dr. Coulson was convinced that even with modern methods of low temperature carbonisation, the possibilities of the coal of the Dore river area being worked on any commercial scale may be discounted. He could not

He could not advise the expenditure on further trial drifts to supplement those made by early investigators. He considered that there is no continuity of outcrop of the coal owing to numerous faults and slippings; the quality of the coal is very variable and is usually poor; the thickness of the seam is either variable or small, or has a false appearance of value imparted to it by the presence of carbonaceous material which is little more than a shale; and finally, the coal-bearing sandstone is kneaded

up

and crushed by earth-movements owing to its position between two hard limestones which have acted as crushers as to be usually impossible of being worked on a commercial scale. As a potential source of fuel for the North-West Frontier Province, the Dore river coal may be ruled out. Dr. Coulson considered that efforts should be directed towards proving the coal to the north of the Baroch in the Kohat district rather than in wasting further money on the Hazara coal.

SO

ance.

Copper. 54. Thin films and small stringers of malachite were found by Dr. Dey in an aplite vein occurring on a hill about 1 mile south

west of Simirkacha (22° 35' : 83° 51'). The Jashpur State, Eastern States Agency.

occurrence has, however, no economic import55. Dr. A. L. Coulson notes that frequent small occurrences of malachite of mineralogical interest but no economic value

occur in the Neocomian shales and at the base of the South Waziristan.

Shahur Tangi (Pab) sandstones west of Spli Toi Post (32° 20': 70° 0') and in the hills south-west of Haidari Kach (32° 19' : 69° 59') in South Waziristan.

56. Mr. Dutt reports the occurrence of copper pyrites associated with tuffs by the side of the stream about one mile north-west of

Kanse (21° 12' : 96° 21'), Kyaukse district. Kyaukse district, This occurrence has been known for several Burma. years but as the ore is

very

indefinite and scanty no attempt has been made to exploit the deposit. 57. At the request of the Madras Government Mr. Crookshank

examined a deposit of copper-ore found in Nellore district, the course of well-sinking at Ganugupentapalli Madras.

near Udaygiri in the Nellore district. On his arrival he found that the well had recently been lined with concrete, consequently he was unable to see anything of the deposit. He was, however, shown some pieces of copper pyrites by the villagers, who were under the impression that the ore was gold.

According to the villagers a rich vein of ore about one foot thick was encountered at one side of the well. It did not extend in depth, nor could it be traced laterally across the well.

A search was then made for copper-ores in the surrounding chloritic quartzites. Although these are the country rocks of the copper-ore no surface indications of copper were found in them in or around the village.

It is thought that the deposit, though rich, is of trifling size and of no economic importance. In this it resembles a number of other deposits of copper found in the Nellore district. 58. Mr. Crookshank reports traces of copper in the rocks 2 miles

E. N. E. of Kottapalli (18° 21': 81° 18'). Bastar State, Eastern The occurrence is not considered to be of any States Agency.

economic importance.

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