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The centre of this area is occupied by a large mass of evengrained and unfoliated granite, which shows marginal chilling with production of granophyric texture.

To the west of this lies an assemblage of conglomeratic grits, some of which are volcanic in origin, vesicular traps, rhyolites and felsites, with some phyllites and a prominent hard quartzite. These have been attributed to the Sakoli series by Mr. Bhattacharji.

To the east the basement grit of the Cuddapahs rests upon the granite and is succeeded upwards by the limestones.

115. Mr. B. C. Gupta continued his work in Drug district, and mapped portions of sheets 64 D/10, 64 D/14, and Drug district, C. P. 64 H/2.

The area mapped resembles that described in the General Report for 1936 except that the two lowest formations, the banded hematitequartzites and the phyllitic schists, were not exposed.

New features are the huge dykes of brecciated quartzite extending in a north-westerly direction across the granitic gneisses and porphyries. The cracks in these are generally filled with secondary veins and crystal aggregates of quartz. Another interesting observation is the marginal chilling of the granite to a quartz-porphyry. This has been noted in several areas, but the clearest one is the granite-porphyry junction in the bed of the Seonath river north of Dorke (20° 44' 80° 38').

An analysis of quartz-porphyry collected by Mr. Gupta in the Drug district, was made in the Department Laboratory. It proved to be almost identical with analyses of the well known quartzporphyries from Glencoe and Arran in Scotland. This is an important addition to our knowledge of these rocks, and proves the cor rectness of Mr. Gupta's views concerning them.

116. Dr. A. K. Dey continued his work in Jashpur State and mapped parts of the following sheets during the field-season 1936-37: 73 A/4, B/1, B/3; 64 N/10, N/14, N/15 and 64 M/S.E.

In addition to the rocks already mentioned in the General Report for 1936,1 Dr. Dey noted some grits, sandstones and ferruginous

Jashpur State, Eastern States Agency.

shales near Patia (22° 58′ : 84° 1′) and in the Khuria highlands. These rocks occur in small discontinuous outcrops or as scattered rock fragments around the hills. The late Mr. Hiralal referred them to the Lameta series on account of their lithological characteristics and infra-trappean position. This correlation is, however, tentative, in the absence of fossil evidence, for similar rocks also occur in the Upper Gondwana formation. The base of the formation is nowhere clearly seen but there is little doubt that it rests directly on the eroded surface of the Archæans. These rocks are overlain by the Deccan trap, but owing to extensive weathering under tropical conditions the trap is altered to laterite. It is, however, possible to find by careful search fragments of basaltic rocks with the laterite. Another rock type not met with during the previous field-season is carbon-phyllite. It is found with the gneissic rocks at Chichli (23° 6' 83° 44') in the Khuria highlands.

The stratigraphical sequence of the rock formations present in the area is given in the following table:

Laterite.

Deccan trap.

? Lameta series (grits, sandstones and ferruginous shales).
[Granitic suite, consisting of granites, granitic gneis-
ses, granodiorites, pegmatites, aplites, quartz-
Archæan veins, etc.

| Iron-ore series, consisting of phyllites, mica-schists,
hornblende-schists, amphibolites, chlorite-schists,
talc-schists, etc.

BIBLIOGRAPHY.

117. The following papers dealing with Indian geology and minerals were published during the year 1937 :

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Conservation of India's Coal. Iron and

Coal Trades Review, CXXXIV, 1090. Constructive proposals for the Coal Industry. Commerce, LIV, 841-842.

Danger of Fire in Coal Mines. Colliery Guardian, CLIV, 87.

Deep Mining in Mysore. Mining Magazine, LVII, 258-259.

Drilling Mud. (Review of the Paper by P. Evans and A. Reid on "Drilling Mud: its Manufacture and Testing", Trans. Min. Geol. Inst. Ind., XXXII). Nature, CXL, 1025.

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1936. Science and Culture, III, 38-41. The Geological Mining and Metallurgical Society of India. Science and Culture, III, Supplement, 17.

Geological Survey in 1936. Science and
Culture, III, 105-106.

The Geological Survey of India. Science
and Culture, III, Supplement, 2-3.
The German Expedition to Nanga Parbat.
Nature, CXXXIX, 1099.

Glass Industry in India. Science and
Culture, III, 170-171.

History of Coal Industry, 1937. Commerce, Special Supplement, December, 1937, 28, 57.

The Indian Coal Industry. Capital, Indian Industries, Trade and Transport Supplement, December, 1937, 46-47.

Indian Coal Industry.

Chief Inspector's

Report. (Summary of the Report of the Chief Inspector of Mines in India, 1935). Iron and Coal Trades Review, CXXXIV, 322.

Indian Coal Industry in 1936. Colliery Guardian, CLV, 1118.

Indian Coal Mining Industry. Mining Journ., CLXXXXVII, 511.

Indian Earthquakes. Nature, CXXXIX, 639.

Indian Gold Mines. Mining Journ., CLXXXXVI, 240-241.

India's Mineral. Industry. Mining Journ., CLXXXXVI, 77-79.

India's Mineral Output. Iron and Coal Trades Review, CXXXV, 938.

India's Mineral Output during 1936. Commerce, Special Supplement, December, 1937, 27, 34.

India's Mineral Production

for 1935.

(Abstract of Dr. A. M. Heron's paper in Rec. Geol. Surv. India, 71, 233-327). Mining Magazine, LVI, 67. India's Mineral Production for 1936. Mining Magazine, LVII, 322.

Indian Notes: (1) Deepening Kolar Mines. (2) C. P. Bauxite and Copper Scheme. (3) Rescue Work in Coal Mines. (4) Cement and Lead Ore. Mining Journ., CLXXXXVII, 389.

The Indian Oil Industry. Nature, CXL, 765-766.

Kashmir Earthquake of November 14. Nature, CXL, 886.

The late Rao Bahadur H. Narayana Rao; Obituary. Quart. Journ., Geol. Min. Met. Soc. Ind., VIII, 155-157. Meteorites. Current Science, VI, 257.

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