Igneous rock the partial melting of rocks within the mantle and crust. Extrusive igneous rocks cool and solidify quicker than intrusive igneous rocks. They are formed by the cooling of molten magma on the earth's surface. The magma, which is brought to the surface through fissures or volcanic eruptions, solidifies at a faster rate. Hence such rocks are smooth, crystalline and fine-grained. Basalt is a common extrusive igneous rock and forms lava flows, lava sheets and lava plateaus. Some kinds of basalt solidify to form long polygonal columns. The Giant's Causeway in Antrim, Northern Ireland is an example. The molten rock, with
Geological Survey of Newfoundland and Labrador was not until the 1930s, under the leadership of Government Geologist A.K. Snelgrove, working at Princeton University, that the Geological Survey was revived and a continuous series of geological investigations commenced within the country's Department of Natural Resources. Geological Survey of Newfoundland and Labrador The Geological Survey of Newfoundland and Labrador is a scientific research agency that is part of the Department of Natural Resources of the Government of Newfoundland and Labrador. It is the agency responsible for performing geological mapping and surveying which provides geological maps, reports, and mineral analysis, and for developing Newfoundland and Labrador's natural resources and