Memoirs of the Geological Survey of India, Volume 16
General Books, May 11, 2012 - 96 pages
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1880 Excerpt: ...in greatest force on the right bank of the Penner, between Kaluvaya and Thalagapur, whence they run to the south-east as a narrowing but tolerably distinct set of strata as far as Saidapuram. About halfway down the southern course of these, and on their western side, come hornblendic schists, occasionally massive (coarsely crystalline with radiated assemblages of short needles of hornblende), but mainly schistose and acicular, and these gradually increase in width and persistence down to the Swarnamukhi. To the north of the Penner the hornblendic and more highly schistose bands are not quite so distinct, though they are traceable as such for some short distance on towards Udayagiri. Eastward of a line drawn from the latter village past Yarabali on the Penned through Tummulatalupuru to Ojili Less schistose band" on the Swarnamukhi, the rocks become gradually coarser and more distinctly bedded, though there are still frequent intercalations of fine mica schists with a more quartzose constitution, with separate beds of quartz-rock or quartz-schist. About Saidapuram and Tummulatulapuru there is a strong run of Gametiferous baud garnetiferous strata, and this is traceable at intercupriferous. vals right up to the northern edge of the sheet, where also are associated cupriferous schists well known as the copper beds of the Nellore district. The garnets in these beds are sometimes quite remarkable in their size, beauty of crystallization, and number. Towards the line of Nellore and Gudur, a few thin outcrops of more Ridges of massive massive grey gneisses of quartz felspar and horn neisa-blende occur, and these are, if anything, in greater force to the northward on the other side of the Penner near Buchireddipalem, where this rock has been quarried for t...