OPHIOLITES: PERSPECTIVES FROM FIELDWORK IN THE APPALACHIANS

• Main Author: Jean H. Bédard
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Patience; Newfoundland
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.677.2680; http://www.elementsmagazine.org/archives/e10_2/e10_2_dep_perspective2.pdf

I love ophiolites. They contain a huge variety of rocks, preserved and arrayed on a scale that makes every outcrop a possible discovery site! Had I the option, I would spend the rest of my career investigating the Bay of Islands Complex in Newfoundland, where the rocks wait for someone who has the patience to listen to their story. Oceanic crust formed by seafl oor spreading covers about 75 % of Earth’s surface but is diffi cult to access. Submersible expeditions and ocean drilling yield valuable but expensive and necessarily limited views. Ophiolites preserve oceanic lithosphere on land, which allows a more complete perspective to be developed as the rocks can be mapped and examined in the fi eld. The Canadian Appalachians are richly endowed with Ordovician ophiolites preserved by the closure of the Iapetus Ocean. Research on these rocks not only helps us to understand how Earth’s biggest magmatic system operates, but contributed to the devel-opment of plate tectonic theory by providing unambiguous evidence of the existence of ocean basins destroyed by subduction. Since ophiolites