Understanding Granites

The origin of granite has for long fascinated geologists though serious debate on the topic may be said to date from a famous meeting of the Geological Society of France in 1847. My own introduction to the subject began exactly one hundred years later when, in an interview with Profes sor H. H. Read, I entered his study as an amateur fossil collector and left it as a committed granite petrologist - after just ten minutes! I can hardly aspire to convert my reader in so dramatic a way, yet this book is an attempt, however inadequate, to pass on the enthusiasm that I inherited, and which has been reinforced by innumerable discussions on the outcrop with granitologists of many nationalities and of many shades of opinion. Since the 1960s, interest in granites has been greatly stimulated by the thesis that granites image their source rocks in the inaccessible deep crust, and that their diversity is the result of varying global tectonic context. So great a body of new data and new ideas has accumulated that my attempt to review the whole field of granite studies must carry with it a possible charge of arrogance, especially as I have adopted the teaching device of presenting the material from a personal point of view with its thinly disguised prejudices.

In Granite and Grace Michael Cohen reflects on a lifetime of climbing, walking, and pondering the granite in Yosemite National Park at Tuolumne Meadows. This high-country region of Yosemite is dominated by a young, beautifully glaciated geological formation known as the Tuolumne Intrusive Suite. It does not include familiar Yosemite icons like Half Dome, yet geologists describe this granitic realm at over 8,000 feet as “an iconic American landscape.” Drawing together the humanistic and scientific significance of the wild landscapes he traverses, Michael uncovers relationships between people and places and meaning and substance, rendering this text part memoir—but also considerably more. On-the-rock encounters by hand and foot open up a dialogue between the heart of a philosopher and the mind of a geologist. Michael adds a literary softness to this hard landscape, blending excursions with exposition and literature with science. It is through his graceful representations that the geological becomes metaphorical, while the science turns mythological. This high country, where in 1889 John Muir and Robert Underwood Johnson planned what would become Yosemite National Park, is significant for cultural as well as natural reasons. Discoursing on everything from Camus’s “Myths of Sisyphus” to the poems of Gary Snyder, Michael adds depth to an already splendorous landscape. Premier early geologists, such as François Matthes, shaped the language of Yosemite’s landscape. Even though Yosemite has changed over half a century, the rock has not. As Michael explores the beauty and grace of his familiar towering vistas, he demonstrates why, of the many aspects of the world to which one might get attached, the most secure is granite.

This volume brings together a collection of papers that summarize current ideas and recent progress in the study of granite-related mineralization systems. They provide a combination of field, experimental and theoretical studies. Papers are grouped according to the main granite-related ore systems: granite-pegmatite, skarn and greisen-veins, porphyry, orogenic gold, intrusion-related, epithermal and porphyry-related gold and base metal, iron oxide-copper-gold (IOCG), and special case studies. The studies provide a broad spread in terms of both space and time, highlighting granite-related ore deposits from Europe (Russia, Sweden, Croatia and Turkey), the Middle East (Iran), Asia (Japan and China) and South America (Brazil and Argentina) and spanning rocks from Palaeoproterozoic to Miocene in age.