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Rock-salt, Salt Range, Punjab.
86. During the latter part of January, 1937, Mr. E. R. Gee again. paid a short visit to the Salt Range in order to advise on the exploratory measures for rock-salt that are being carried out by the Northern India Salt Revenue. Within the Mayo mine at Khewra (32° 38': 73° 1′) he noted that appreciable development work had been carried out at the High and Intermediate Levels in the Buggy and Sujowal seams. This recent work made possible the mapping of these seams of rock-salt and he was thus able to suggest further extensions. At the Low Level, the Pharwala development tunnel had been continued eastwards and, as previously predicted by Mr. Gee, had proved the Buggy seam. The seam had turned out to be of excellent quality and a number of chambers were being excavated to the south of the tunnel. In the South Pharwala area, work had mainly centred around the sublevel where the Middle Pharwala seam was, as anticipated, proving to be a valuable source of supply. Mr. Gee suggested further extensions in these areas.
Exploration tunnels for proving the rock-salt deposits of the area north of the present Khewra mine, of the slopes west of Chanuwala (32° 44': 73° 10′) and near the exit of the Makrach gorge (32° 40′: 72° 53') were also inspected. Mr. Gee reports that these tunnels have not been extended sufficiently far to allow the expression of a definite opinion but that the evidence so far afforded was promising.
He also examined the recent exploratory tunnels near Kalabagh village (32° 58′: 71° 33′) and made a number of suggestions regarding further development.
A description of the rock-salt deposits of the Salt Range is included in a recent paper by him entitled 'The Economic Geology of the northern Punjab, with notes on adjoining portions of the North-West Frontier Province' published in the Transactions of the Mining, Geological and Metallurgical Institute of India, Vol. XXXIII, Pt. 3, (1937).
87. Mr. Das Hazra reports the occurrence of two saline springs in the Siwaliks of Udhampur, viz., at Berga (32° 48′: 75° 2′) and Suruin Sar (32° 47': 75° 2′). The water is drunk by the local people as an aid to digestion and as a cure for stomach ailments.
Salt springs, Udhampur district, Jammu,
88. Mr. H. M. Lahiri noted a hot spring at Tatwani (32° 8′ : 76° 11') and a salt spring at Bagh (32° 1′: 76° Salt springs, Kangra 11'), the latter issuing from Nahan rocks close district, Punjab. to a fault.
Amherst district, Burnia.
89. The area mapped by Dr. Iyer in Amherst district is by no means rich in minerals, but in the Kya-In township, in sheet 95 E/14, alluvial washing for tin is carried out on a small scale in several places. Veins and apophyses of granite carrying tin have impregnated the country rocks to some extent, and weathering and washing has concentrated the tin in a number of places. localities where tin washing was noted by Dr. Iyer are as follows:-(i) Kawalawa Chaung, east-north-east of Paka Taung, (ii) on the path between Kawalawa and Anankwin, (iii) Thanbaya tin mines, (iv) Kawalawa tin mines, and (v) Dayingouk Chaung. In each place about ten men were employed.
Water (see Engineering and Allied Questions).
90. Mr. A. B. Dutt reports the occurrence of wolfram in quartz veins traversing the coarse-grained biotite-granite about half a mile E. N. E. of Hill A 3188, W. S. W. of Yengan State, Burma. Nyaunggyat (21° 6' 96° 21′), Yengan State. Several pits had been dug and one adit driven. The pits had been long abandoned but the adit was worked up to September, 1936. Mr. Dutt considers the deposit to be promising but points out that no good road exists to a railway station, the nearest being situated 30 miles away.
Several abandoned wolfram workings were noted by Mr. Dutt in the granite hills about two and a half miles south-west of Nyaunggyat. The wolfram appears to occur only in small quantity and to be of little economic interest.
91. An old working, said to be of wolfram, was also noted by Mr. Dutt in the hill about two miles south-east of Thwingyaung (21° 6' 96° 13'), Meiktila district. This area Meiktila district, Burma. was opened up during the War about 20 years ago. Mr. Dutt was unsuccessful in his attempts to locate wolfram in the working.
While at Kywegan (21° 3': 96° 11'), Mr. Dutt identified for a villager some good specimens of wolfram, said to have been obtained from the hills east of Lethagon (21° 1' 96° 12), Meiktila district. A thorough search, however, failed to disclose the place of origin of the specimens.
92. During the 1936-37 field season the Burma Circle consisted of Mr. E. L. G. Clegg, Superintending Geologist in charge, Messrs. E. J. Bradshaw and V. P. Sondhi, Geologists, and Dr. L. A. N. Iyer and Mr. A. B. Dutt, Assistant Geologists. At the close of their field season's work Mr. V. P. Sondhi and Dr. L. A. N. Iyer were transferred to India from Burma, to reduce the party to the strength desired by the Government of Burma.
From the 1st April, 1937, a separate Burma Geological Department was created, consisting of Messrs. Clegg, Bradshaw and Dutt, who were placed on foreign service with the Government of Burma.
93. During the field season Mr. Clegg continued the extension of his survey of the Mogok Stone Tract by examining various outcrops in sheets 93 B/4, 93 B/3, 93 B/2 between Mandalay and Thabeitkyin, and then continued mapping in sheets 93 A/4 and A/8 north of Thabeitkyin.
The area south of Thabeitkyin is included in La Touche's map. of the Northern Shan States1 but no attempt was made by La Touche to divide the rocks into the calcaMandalay hill. reous and granitic rocks which were known to exist. Mr. Clegg found that all the isolated outcrops which protrude from the alluvium in the southern area consisted of either metamorphosed calcareous rocks, metamorphosed calcareous rocks intruded by granite, or solely of granites. The exposures commence at Mandalay Hill, which consists essentially of crystalline limestones and diopside calciphyres, penetrated on the eastern flank by granite and pegmatite dykes. The granite, which is excellently exposed in the quarries on the east side of the hill, varies from fine aplitic to coarse porphyritic biotite granite and in it quartz veins
1 Mem. Geol. Surv. Ind., XXXIX, Pt. 2, (1913).
are common. The general strike of the granite dykes is N. 5° W. The calciphyre is very contorted and has veins of granite material injected along, as well as across, the bedding.
Seven miles north of Mandalay the Kyanigan hills are composed for the greater part of metamorphosed calcareous rocks with an acid igneous intrusion on the south-west. The Kyanigan hills. calcareous series. are generally fine-grained, banded, show local contortions and weather irregularly according to the composition of the bands; they consist of diopside-granulites containing free calcite, scapolite, diopside, quartz and felspar; occasionally, as one mile east of Kyanigan, iron pyrite is present. Other varieties include coarse crystalline limestone containing calcite rhombs up to half an inch in length, and a medium-grained calcareous quartzite consisting of a mosaic of quartz and a little felspar with interstitial calcite. The granite is mostly coarse, biotitic and gneissic; thin bands richer in biotite are almost schistose, and white bands consist almost entirely of tourmaline, quartz, and felspar. Sometimes a fine-grained biotite-muscovite gneiss occurs in association with the tourmaline granite.
Rocks west of Chaung-Magyi chaung.
Eleven miles north of Mandalay the isolated Boywa hill consists entirely of gneissic medium-grained biotite-granite.
In Sheet 93 B/3 a large granite boss lies to the west of the ChaungMagyi chaung. West of this boss the Sagyin hills rise abruptly as a straggling line of irregularly shaped hills made up of crystalline limestone and metamorphosed calcareous rocks of a more impure nature. These continue intermittently to the north and form the calcareous hills to the north and south-west of Pinle-In; they are broken by granitic intrusions, which form outlying smaller intrusions of the massive boss to the east, and from which they are separated by an alluvial valley possibly overlying calcareous rocks. Northwards metamorphosed calcareous rocks are found bounding on the south another of these outlying granite intrusions immediately north by east of Nyaungwun.
The Sagyin Hills consist of massive white crystalline limestones which dip east by north at 42°. Some of these marbles contain rhombs of calcite up to three inches in length; others are finely saccharoidal. In the low hills just over a mile S. S. E. of Sagyin a little crushed calcareous gneiss
consisting of quartz, diopside, sphene, a little scapolite and felspar, occurs intercalated in coarse crystalline limestone. In the bills north of Sagyin, diopside, diopside, phlogopite phlogopite and pink spinel were found to be common in the calciphyres near Tawyokyaung, whilst Hngetkyizin hill consists of white crystalline limestone and a medium-grained calcareous gneiss composed of plagioclase, a little orthoclase and microcline, diopside, sphene, a little quartz and epidote. The Pinle-In-Ywezu calcareous series is very similar to that found further to the south. It is intruded to the east by biotite-granite of both fine and coarse-grained types. The junction is not sharp and, near to it, granite has penetrated the calcareous rocks in a series of bands and small bosses. At the extreme north the hills end up in a tourmaline granite dyke in which crystalline limestone and diopside-calciphyre is caught up.
North-east of Nyaungwun the calcareous series consists of calciphyres composed mainly of calcite, a little diopside, sphene and scapolite and dips east by north at about 40°. In this area also
Hills north of Nyaungwun.
granites intrude the series.
North-east of Magwe Taya calcareous rocks, mostly of calciphyre and calcareous gneiss, are found as a fringe to the main granitic. intrusion to the east. Close to the boundary the latter is a tourmaline-granite.
The main granite mass of sheet 93 B/3 and 7 forms an almost impenetrable mass of mountainous forest country. The common type of granite present is normal biotiteMain granite mass. granite but its texture varies from coarsely gneissic to fine-grained. The fine-grained is indistinguishable from the Kabaing granite of the Mogok area. Near the contacts of the granite with rocks of sedimentary origin, tourmaline-granite is common, as is for example seen (1) one and a half miles north of Sedaw, (2) below Sedaw inspection bungalow, (3) north-west of Kadetchin and (4) four miles east of Nyaungwun.
This main granite mass continues north into sheet 93 B/2 and 6, in the same type of mountaincus forested country. Although the highest point (3,531) in this granite range Pyingyitaung ridge. lies to the south, the most prominent peaks along the watershed to the north are never less than 2,300 feet. Flanking this intrusion on the west are rocks of the metamorphosed