The Journal of Geology, Vol. 46, No. 3, Part 2 (Apr. - May, 1938), pp. 505-520 (16 pages) A modified variation diagram for plotting groups of chemical analyses of ...

IN this first volume the author provides an introduction to the science of petrography. After dealing with the constituents (minerals), and their relations (textures), he gives in summary some ...

WITH the collaboration of Dr. A. K. Wells, this well-known text-book has been revised and extended until now it is virtually a new book. Among the new features are chapters dealing with the ...