The Samail Ophiolite, also known as the Semail Ophiolite, is a large, ancient geological formation in Oman and the United Arab Emirates in the Arabian Peninsula. It is one of the world's largest and best-exposed segments of oceanic crust, made of volcanic rocks and ultramafic rocks from the Earth's upper mantle that was overthrust onto the continental crust. This ophiolite provides insight into the dynamics of oceanic crust formation and the tectonic processes involved in the creation of ocean basins.

The Arabian Peninsula, or Arabia, is a peninsula in West Asia, situated northeast of Africa on the Arabian Plate. At 3,237,500 km2 (1,250,000 sq mi), comparable in size to India, the Arabian Peninsula is the largest peninsula in the world.