||October 30, 2001
GSA Release No. 01-43
|| Ann Cairns
Director Communications and Marketing
New GSA Publication on Ophiolites and Oceanic Crust
BOULDER, Colo. - The Geological Society of America (GSA) recently published Special Paper 349: Ophiolites and Oceanic Crust: New Insights from Field Studies and the Ocean Drilling Program, edited by Yildirim Dilek, Eldridge Moores, Don Elthon, and Adolphe Nicolas.
Ophiolites (from the Greek words "ophis" --snake, and "lithos"--rock) are fragments of the oceanic crust and mantle that are found preserved in the Earth's mountain belts. They provide valuable information about how ocean crust develops at spreading centers. In addition, because no ocean crust is older than about 200 million years, ophiolites represent the only source of information available about the oceanic crust prior to that time. Ophiolites are found throughout the world, including such places as Alaska, Argentina, the Balkans, California, China, Cyprus, Greece, Japan, New Guinea, Newfoundland, Oman, Taiwan, Tibet, and Turkey.
"Ophiolites are geological windows into the history of the Earth and Earth processes," Dilek and Moores said. "They provide important clues to how ocean basins formed and disappeared in the past and how the dynamic planet Earth's paleogeography (distribution of continental masses and oceans) looked many millions of years ago. The discovery of copper in ophiolitic volcanic rocks in the Mediterranean region ushered in the Bronze age in the history of human civilizations. Studies of ophiolites have advanced the methods and theories of geology for more than 200 years. This book presents state-of-the-art information on the significance of ophiolites in studying different aspects of the Earth's history."
Since 1972, when the first GSA Penrose Conference on Ophiolites was convened, these unique features have galvanized multinational and multidisciplinary efforts to study and decipher these complexes and their significance for understanding oceanic lithosphere formation.
The second Penrose Conference on ophiolites in 1998 brought together 86 experts in structural geology, tectonics, geophysics, petrology, and geochemistry to explore new advances and discoveries concerning ophiolites and related drilling from the oceanic crust. Special Paper 349 includes 39 papers from this conference plus updated information on the evolution of ophiolites and modern oceanic crust, and integrates new interdisciplinary data from drilling and other studies of in-situ oceanic lithosphere with new results from field studies of ophiolite complexes around the world. This volume also highlights the outstanding questions and future directions for research on ophiolites.
"While deep-sea drilling provides valuable samples of the oceanic crust, the exposed ophiolites on land provide a complete sequence and thus a record of spreading ridges and important evidence for structural, magmatic, and hydrothermal processes in seafloor spreading that occurred especially at times prior to 170 Ma. Some ophiolites include metallic mineral concentrations rich enough to form ore deposits, including large copper-iron sulfide deposits. In fact, the Troodos ophiolite in Cyprus was the source of most of the copper in the Bronze Age of the Mediterranean. The Greek word for Cyprus, "kypros," becomes "cuprum" in Latin, which is the Latin term for copper (and the source of our symbol for the element-Cu). Thus the Island of Cyprus is the Island of Copper," Dilek and Moores explained.
For more information on Special Paper 349, visit the GSA Bookstore.
SPE349, 560 p. (including index, bibliographies, and color figures), softcover, ISBN 0-8137-2349-3
GSA-Members $104.00 (after 20% Member discount.)