GeoLog

Imaggeo on Mondays: Isolated atoll

Laura Roberts-Artal September 25, 2017

Isolated . Credit: Fulvia Favaro (distributed via imaggeo.egu.eu)

Covering a total area of 298 km², the idylic natural atolls and reefs of the Maldives stretch across the Indian Ocean. The tropical nation is famous for it’s crystal clear waters and picture perfect white sand beaches, but how did the 26 ring-shaped atolls and over 1000 coral islands form? Coral reefs commonly form immediately around an island, creating a fringe which projects seawards from the sh ...[Read More]

GeoSciences Column: Catch of the day – what seabirds can tell us about the marine environment

Laura Roberts-Artal September 22, 2017

An adult northern gannet mid-flight . Credit: Andreas Trepte , distributed via Wikimedia Commons .

Off the coast of Germany, a male northern gannet (for ease, we’ll call him Pete) soars above the cold waters of the North Sea. He’s on the hunt for a shoal of fish. Some 40km due south east, Pete’s mate and chick await, patiently, for him to return to the nest with a belly full of food. Glints of silver just below the waves; the fish have arrived. Pete readies himself. Body rigid, wings tucked in ...[Read More]

GeoTalk: The anomaly in the Earth’s magnetic field which has geophysicists abuzz

Laura Roberts-Artal September 21, 2017

The South Atlantic Anomaly (SAA, the large red area in the image) is a dip in the Earth's magnetic field which allows cosmic rays, and charged particles to reach lower into the atmosphere. This interferes with communication with satellites, aircraft, and the Space Shuttle. While there are theories as to why this occurs, the geologic origin is not yet known. The data were collected by the South Atlantic Anomaly Detector (SAAD) aboard ROSAT. It consists of 10 cm² of Germanium and served as a particle background monitor. The SAAD was used to "safe" the PSPC if rates became too high. Source: ROSAT SAA Guest Observer Facility (NASA Goddard Space Flight Centre) . Credit: S. L. Snowden

Geotalk is a regular feature highlighting early career researchers and their work. In this interview we speak to Jay Shah, a PhD student at Imperial College London, who is investigating the South Atlantic Anomaly, a patch over the South Atlantic where the Earth’s magnetic field is weaker than elsewhere on the globe. He presented some of his recent findings at the 2017 General Assembly. First, coul ...[Read More]

Mexico earthquakes: What we know so far

Laura Roberts-Artal September 20, 2017

USGS interactive map of M 7.1 earthquake .

On Friday 8 September 2017 at 04:49 am UTC, a magnitude 8.1 earthquake hit off the coast of Mexico, 87 km SW of Pijijiapan. According to the U.S. Geological Survey, the epicentre was at 15.07 N, 93.72 W at a depth of about 69.7 km. Yesterday, another strong (magnitude 7.1) earthquake hit central Mexico, 55 km SSW of the city of Puebla and 120 km south of Mexico City. Despite the lower magnitude, y ...[Read More]