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Calcareous conglomerate,

from Gwalior, for deter. I mination.

Col. D. G. Pitch&R, / The rounded fragments are almost wholly composed of calcic car bonate in a micro-crystalline or
Gwalior.

amorphous condition with large quantities of light green chloritic minerals in some, and hydrated
iron-oxide in other fragments. The whole is cemented with distinctly crystallized calcite, the
crystals in which invariably exhibit zones of ferruginous inclusions.

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Cakes, but not Does not cake. Does not cake,

strongly. Ash- dark brown. but sinters Ash- dark brown.

slightly. Ash-dark red.

Does not cake, but

sinters slightly. Ash-brick red.

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Moisture Volatile matter Fixed carbon Ash . .

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100 00

Ash-gray. Quantity received, 145 oz.

List of Assays and Examinations made in the Laboratory, Geological Survey of India, during the months of

February, March, and April, 1891-concluded.

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Chalcopyrite and pyrite,

from Pache (near Pakyang) Sikkim, for copper.

Sample Nos. 3, 7, 8, f, , 10, 14, 15, and 16, carbonaceous shale.
P. N. Bose, Geologi. | Specimen L.
cal Survey of India. Quantity received, 5t oz.

Contains 20:31 per cent. of copper (Cu.)

ERRATA.

MEMOIRS, GeoLOGICAL Survey of India, Vol. XXIV, Pt. 1. Page 1, in second line of title, for A read J.

3, line 13, for on read of.
4, line 6, below Talchir insert Metamorphics.
5, last line (references), for 4 read 5, and for 5 read 4.
7, line 1, for 1854 read 1855.
7, line 5 from bottom, for d. J. Geol. Soc., London, XI, 555, read J. A.S.B.

XXIV, 347-353.

7, line 3 from bottom, for V, 179 read XI, 555. , 8, in marginal heading of last paragraph, for 1886 read 1866. , 9, line 16 from bottom erase 7 after 1872.

15, line 9, for Optee read Ooptee.

15, line 10, for Omerghor read Oomerghor. , 32, in well section, insert White sandstone -15' 0" above Coal-'o".

35, line 2 from bottom, for Gogra read Gogri.

37, line 4 from bottom, for Badeo read Badee.
, 39, line 8 from bottom, for following read flowing.

49, line 1, for Sungun read Sungum.
52, line 11, for Lenia read Lonia.

54, line 2 from bottom, for Tannia read Tamia. , 54, bottom line, for Sarni-Patakkra read Sarni-Patakhera. , 56, No. XIV in table, for Gajimdoh read Gajundoh. , 56, No. XVI, in table, for Pala Chourye read Pala Chowrye. , 58, line 2 from bottom, for deposited read dissolved. In map I (1"=4 miles), in scale of horizontal section, for 1056' read 10560'. In upper margin, for Singora field read Sirgora field. The small outlier north of Rajegao coloured as Trap should be coloured as Motur s. In map II, in upper margin, for “Singora" read "Sirgora."

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Boring Exploration in the Daltongunj Coal-field, Palamow; by Tom D.

LA TOUCHE, B.A., Deputy Superintendent, Geological Survey of

India. (With a map.)

Introductory remarks.—The investigation of the Daltongunj coal-field by means of borings, carried out during the past cold weather, was undertaken with the object of testing the capabilities of the field for the production of coal in sufficiently large quantities to warrant the construction of a railway that should make the coal available for use in Upper India,-a partial exploration made under the supervision of Dr. Saise in 1890 having raised hopes that coal of good quality would be found in abundance, his estimate giving a total quantity of “not less than 161,377,000 tons of coal containing 11'7 per cent. of ash,” The borings recently made have, I regret to say, led to the conclusion that the estimate made by Dr. Saise both as to the quantity and quality of the coal, was too favourable; and though there is undoubtedly a large amount of coal in the field, yet the conditions of its distribution are such as to render it extremely doubtful whether a sufficiently large output could be obtained to encourage the construction of a railway for the sole purpose of carrying the coal to other parts of India.

It will be unnecessary here to give any account of the physical features of the district of Palamow in which the coal-field under discussion is situated, as these have already been fully described by Mr. Hughes (Memoirs G. S. of I. Vol. VIII, Part 2), but the more accurate survey I was enabled to make of the area actually occupied by the coal-bearing rocks has led me to differ in some points from the conclusions arrived at by Mr. Hughes, and before discussing the borings, it will be advisable to draw attention briefly to the surface conditions in this area. Surface rocks.—The coal-bearing rocks (shown by Dr. Feistmantel from their fossil

, contents to be of Karharbari age*) occupy an area of about * Records G. S. of I. Volume XVI, page 175. 30 square miles in the valley of the Kod at its junction with

its tributaries the Amanat and Durgnoti. On all sides they are surrounded by Talchir shales, the boundary being for the most part very obscure except on the north side, where it is marked by a strong fault, which brings the coal measures nearly into contact with crystalline rocks. Over the greater part of this area the rocks visible at the surface are coarse, friable sandstones, consisting almost entirely of angular or slightly rounded grains of quartz and more or less decomposed felspar, showing much false bedding, and often containing strings of

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