Mike Searle on Ophiolite

12/18/21 • 28 min

As the name implies, oceanic lithosphere underlies the oceans of the world. Except when they are ophiolites, when oceanic lithosphere is thrust on top of a continental margin. Are ophiolites a special kind of oceanic lithosphere? Or are there peculiar tectonic circumstances that emplace denser oceanic rocks on top of lighter continental ones? Mike Searle addresses these questions, and reveals the sequence of events that created the world's most extensive and best-preserved ophiolite - the Semail ophiolite in Oman.

Mike Searle is Emeritus Professor of Earth Sciences at the University of Oxford and at the Camborne School of Mines in Cornwall.

For podcast illustrations, go to geologybites.com.

Mike Searle is Emeritus Professor of Earth Sciences at the University of Oxford and at the Camborne School of Mines in Cornwall.

For podcast illustrations, go to geologybites.com.

Previous Episode

Mackenzie Day on Dunes

Some of the most extensive sandstone deposits in the world were deposited by wind. How do such aeolian rocks differ from water or ice-deposited rocks? And what do they reveal about the environments in which they formed? In the podcast she describes the dunes we see in the geological record on Earth, as well as on Mars and on a comet, and explains what we've learned from them.

Mackenzie Day is an Assistant Professor in the Department of Earth, Planetary, & Space Sciences at the University of California Los Angeles. She is an expert in aeolian processes. In the podcast she describes the dunes we see in the geological record on Earth, as well as on Mars and on a comet and explains how they formed.

Go to geologybites.com for podcast illustrations and to learn more about the series.

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Chuck DeMets is Emeritus Professor of Geoscience at the University of Wisconsin, Madison. He studies the magnetic anomalies in seafloor rocks to reconstruct plate motions at a temporal resolution five times better than has been done hitherto. This has revealed unexpected speed-ups and slow-downs in plate motions that provide juicy puzzles for geodynamicists. In the podcast he focuses on the detailed motions of the Indian plate that show, among other things, that its northward movement actually sped up for a period after the collision with Eurasia before it settled down to a steady slower speed.

Go to geologybites.com for podcast illustrations and to learn more about Geology Bites.