Rockall part of the deeply eroded Rockall Igneous Centre that was formed as part of the North Atlantic Igneous Province, approximately 55 million years ago, when the ancient continent of Laurasia was split apart by plate tectonics. Greenland and Europe separated and the northeast Atlantic Ocean was formed between them, eventually leaving Rockall as an isolated islet. The RV "Celtic Explorer" surveyed the Rockall Bank in 2003. The Irish Light Vessel "Granuaile" (the same name as the steamer on the RIA 1896 botany survey) was chartered by the Geological Survey of Ireland, on behalf of the Department of Communications, Marine and
Rockall base. The nearest permanently inhabited settlement is 366.8 km, or 198.1 nmi, west of the headland of Aird an Rùnair, near the crofting township of Hogha Gearraidh on the island of North Uist at . North Uist is part of the "Na h-Eileanan Siar" council area of Scotland. The exact position of Rockall and the size and shape of the Rockall Bank was first charted in 1831 by Captain A. T. E. Vidal, a Royal Navy surveyor. The first scientific expedition to Rockall was led by Miller Christie in 1896 when the Royal Irish Academy sponsored a study of the