At over 5 million years old, the island of Kauai is the oldest island in the Hawaiian Achipelago. Hawaii, Maui and Oahu are all younger and lie further to the southeast. This island chronology is no coincidence – the Archipelago formed as a result of intra-plate volcanic activity. Intra-plate volcanism occurs where an upwelling magma plume or ‘hot spot’ lies beneath a continental plate. In this ca ...[Read More]
Geosciences Column: Hazard perception – how great is the risk of a rockfall?
In this month’s Geoscience’s column, Sara Mynott discusses the geological hazards associated with climate warming and how recent research sheds new light on our understanding of rockfall frequency. Rockfalls are the free-falling movement of bedrock material from a rock face, a phenomenon also encompassed by the terms ‘landslide’, ‘rockslide’ and ‘rock avalanche’. They range from small debris falls ...[Read More]
Imaggeo on Mondays: Rainbow in stone
Nothing better characterises the wild US West than endless landscapes of red hoodoos, spires of rock protruding from the bottom of an arid drainage basin or badland. Found mainly in desert and dry, hot areas, hoodoos are distinctive from similarly-shaped formations, such as spires or pinnacles, because their profiles vary in thickness throughout their length. Their distinctive colour bands are the ...[Read More]
Geosciences Column: Spotting signs of sea-quakes
A French and Algerian study team seeks markers of underwater earthquakes off the Algerian coast. The team also matched the site’s paleoseismic history to land-based historical reports. Wayne Deeker reports. The Mediterranean Sea represents the boundary between the African and Eurasian plates. Yet the fault segment off the Algerian coast is one of the most active in the western Mediterranean. It is ...[Read More]