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Records of the Geological Survey of India. [vol. vn. 
Geological Notes on past of Nobthebn Hazabibagh, by F. R. Mallet, f. g. s.. 
Geological Survey of India. 
In an early number of these Records (Yol. II, p. 40,1869,) a brief notice was given of 
the metamorphic rocks of Bengal, in the northern part of their area, from the Karakpur 
bills at the north-east corner of the rock-area of the Peninsula, along the lower valley of the 
Ganges and the Son valley, into the valley of the Narbada, where all the older formations 
pass under the Dakkin trap. Throughout that distance, in a west-south-west direction, 
and corresponding with those very marked orographieal features, the gneiss is fringed by less 
metamorphosed rocks—schists, slates, and quartzites. To give shape to the study of these 
rocks, more than from any compulsion of decided views, a tentative classification was then 
attempted, upon general stratigraphical reasoning, occasionally against the apparent (primd 
facie) evidence of local sections. The series thus indicated consisted in chronological order 
of- ‘1st. a fundamental gneiss (undiscriminated); 2nd, gneissic schists and quartzites (of 
M aha bar) corresponding to the less metamorphosed slaty schists and quartzites to the north 
(Rajgir); 3rd, massive gneissoid (foliated) granite, mostly forming domes; 4 th, flaggy 
schists and gneiss with quartzites and amorphous pseudo-gneiss, sometimes conglomeritic 
(Lakisarai, Betia, Sukri, infra-Bijawars of Bandelkand); 5 th, intrusive invasion 
of pegmatite; 6 th, Bijawars (of Bandelkand and the Agori zone of the Son valley). 
The hazardous points of this scheme were known to be—the doubtfully granitic (exotic) 
character of any of the dome gneiss, and principally, the supposition of gncissose rocks 
(No. 4) greatly younger than the schist and quartzite series (No. 2). Both positions were 
placed primarily upon the same general evidence—the universally intense folding, with 
cleavage of the schist and quartzite series, compared with the frequently moderate disturbance 
in a portion of the gneissic rocks, which, moreover, seemed to occupy a position of general 
superficiality as regards the main body of the gneiss and to contain locally debris of the 
quartzite series. 
The detailed survey of which these notes are a first instalment was undertaken in the 
hope of working out some more definite views upon rocks forming so broad a feature in the 
geology of India. The observations refer to what seemed to be a key to the position, where 
the schists and quartzites of Mahabar are well exposed in connection with the gneiss. The 
area especially referred to is contained in sheets Nos. 7 and 8 of the new topographical survey 
of Hazaribagh district, on the scale of one-inch to the mile, of which sheets this note may be 
taken as a description; some observations, however, referring to the adjoining ground where 
the geological mapping was incomplete. As the survey of this region has been interrupted 
by orders of Government, in order to take up the examination of some supposed coal-bearing 
ground at the base of the Eastern Himalaya, it is well to make a record of the work 
so far done. Thus far the views suggested by the sketch-survey have not been upheld 
as applicable to the section here; the massive dome-gneiss, of which some magnificent 
examples occur, is not proved to be in any special sense intrusive, or foreign to the rocks with 
which it is associated; and the flaggy schists with quartzites of the Sukri seem to be an 
irregular basal member of the Mahabar series, rather than a much later and independent 
group; however this relation may still be maintained for the conglomeritic pseudo-gneiss 
of Lakisarai and Bandelkand. 
Immediately to the south of the above-mentioned area (that included in sheets 7 and 8) 
spreads the comparatively level highland of Karrakdiha, the extreme edge of which invades 
sheet 8 in one or two places, as at Gajhandi and Simmeria. To the north again of the 
Mahabar and Bhiaura ranges, the alluvial planes of Bihar stretch to the horizon, save 
here and there where some outlying hill breaks the continuity of the prospect. The area 
under discussion, therefore, comprises a part of the jungly and hilly country which marks the 
