Your cart

Your cart is empty


Not currently available

Geological Society of America Bulletin Volume 16 (Paperback) Loot Price: R656
Discovery Miles 6 560
Geological Society of America Bulletin Volume 16 (Paperback): Geological Society of America
Geological Society of America Bulletin Volume 16 (Paperback): Geological Society of America

Share your images

Geological Society of America Bulletin Volume 16 (Paperback)

Geological Society of America

 (sign in to rate)
Loot Price R656 Discovery Miles 6 560 | Repayment Terms: R61 pm x 12*

Bookmark and Share

Supplier out of stock. If you add it to your wishlist we will send you an email should it become available again.

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. 1905 Excerpt: ... with accessory quartz, biotite, hornblende, magnetite, apatite, titanite, pyrite. pyrrhotite, garnet, and orthoclase. Exclusively decomposition minerals are actinolite, chlorite, and serpentine. Quartz is very variable in amount, ranging from 0 to 30 per cent. The pyroxenic constituent may be exclusively hypersthene, chiefly hypersthene, or less frequently, chiefly augite or exclusively augite or diallage. It constitutes from 10 to 40 per cent of the rock. The plagioclastic constituent is labradorite or labradorite-bytownite and varies from 5 to 50 per cent of the rock. Between the pyroxene, whether hypersthene or augite, and the labradorite there occur reactionary peripheral bands of garnets. Between the garnets and the pyroxene there is a narrow zone of quartz and hornblende. Hypersthene and the anorthite molecule will produce hornblende, quartz, and common garnet (an isomorphous mixture of grossular, almadine, and pyrope). In the case of the monoclinic pyroxene the feldspar molecule is not needed and lime is liberated. These garnet rims are the most striking petrographic features of the gabbro (see plates 57, 58, and 59). Wherever the gabbro has been subjected to pressure, as along the periphery of the intrusive mass, pyroxene is replaced, chiefly by green hornblende and subordinately by biotite. Such a margin of hornblendegabbro is so marked a feature of the Cecil County gabbro mass that it can je mapped as a separate formation. A more or less schistose structure accompanies the development of these two minerals. Along the contacts hornblende also accompanies biotite as a constituent of the gneiss. This contact phenomenon increases the difficulty of separating the two formations. The gabbro is associated with and, through decrease in feldspar, grades i...


Imprint: Rarebooksclub.com
Country of origin: United States
Release date: March 2012
First published: March 2012
Authors: Geological Society of America
Dimensions: 246 x 189 x 15mm (L x W x T)
Format: Paperback - Trade
Pages: 274
ISBN-13: 978-1-130-64007-6
Barcode: 9781130640076
Categories: Books
LSN: 1-130-64007-8

Is the information for this product incomplete, wrong or inappropriate? Let us know about it.

Does this product have an incorrect or missing image? Send us a new image.

Is this product missing categories? Add more categories.

Review This Product

No reviews yet - be the first to create one!

Loyalty partners