GeoLog

Imaggeo on Mondays

Imaggeo on Mondays: Grand Prismatic Spring

Yellowstone National Park, USA, is well known for its outstanding natural beauty. This is the Grand Prismatic Spring in the Midway Geyser Basin, Yellowstone National Park. It is the third largest hotspring in the world and the largest found in the United States, with a maximum diameter of about 90 m. It discharges roughly 2.5 cubic metres of mineral-rich water per minute, which flows down the rock ...[Read More]

Imaggeo on Mondays: Alas, allases are abound!

The Lena River flows throughout Russia from its source in the Baikal Mountains out into the Arctic Ocean, where the delta’s landscape is dominated by ice-rich Yedoma and thermokarst lakes. Thermokarst lakes have been identified as a source of carbon release to the atmosphere and Yedoma-like lake sediments are known to release more methane than any other sediment due to their incredibly high carbon ...[Read More]

Imaggeo on Mondays: Stirring up a sandstorm

These are the outwash plains for the Icelandic volcano, Katla: An outwash plain (or sandur) is a broad, shallowly sloping region ahead of a glacial front. They are made up of material that has been deposited by glacial meltwater, released either by geothermal heating or a subglacial eruption. The extensive volcanism and abundance of ice-capped volcanoes in southern Iceland means that the outwash p ...[Read More]

Imaggeo on Mondays: Metamorphosis

This fold is part of the metamorphic core of the Pyrenees. The shear zone is almost vertical, producing a small parasitic fold (a smaller fold within a larger one), which looks almost as if it continues into the sky. The metamorphic sediments are about 500 million years old and have been deformed several times, most recently during the alpine orogeny. The alpine orogeny was period of extensive mou ...[Read More]