Reynisfjara Beach is the most famous black sand beach on the South Coast of Iceland. Its beautiful black sand, powerful waves, and the nearby Reynisdrangar sea stacks make Reynisfjara a truly unique place to visit.
The reason for the sand at Reynisfjara being black is that it is formed from heavily eroded volcanic rocks (also known as extrusive igneous rocks), which are black (or obsidian) to begin with as they have been formed from cooled lava which turns black as it cools and hardens. The most well-known volcanic rock found in Iceland is basalt, but there are at least 25 different types on the island, including olivine, gabbro, rhyolite, and tholeiite.
The Reynisdrangar Columns were part of, and connected to, the Reynisfjall mountain range during the last ice age, but after long periods of harsh weathering, they have become eroded to the point where they are no longer connected and look as though they sprouted up out of the ocean on their own.
Weathering and erosion continue to reshape the Reynisdrangar Columns on a daily basis. With that in mind, they are constantly changing, so no two visits to the area will produce the exact same sights.
extrusive igneous rock 在 Igneous Rocks | Pictures of Intrusive and Extrusive Rock Types 的推薦與評價
Aug 25, 2013 - Pumice is an extrusive igneous rock with a vesicular texture and very low specific gravity. It is used to make lightweight concrete, ... ... <看更多>