Chloritoid is a metamorphic mineral commonly found inside phyllite rocks – which is shale (a type of mudstone containing clays, silts and muds) that has been metamorphosed several times. Confusingly, chloritoid does not actually contain the element chlorine but instead is an iron magnesium manganese alumino-silicate hydroxide. This particular specimen is from Lyon, France: In larger sized specimen ...[Read More]
Geochemistry, Mineralogy, Petrology & Volcanology
Imaggeo on Mondays: Travertine takeover
This week’s Imaggeo on Mondays is brought to you by Olivier Galland, who took this photo during an incredible outreach adventure in the Andes… The image displays the spectacular Puente del Inca (The Inca Bridge) hot springs, in the Argentinian Andes of the Mendoza province, along the Vacas River, close to the foot of Cerro Aconcagua. When the mineral-rich, sulphurous waters reach the surface, the ...[Read More]
Imaggeo on Mondays: Mammoth structures, springs and snowmelt
Spring waters are rich in minerals, carrying with them dissolved components of the rocks they have travelled through. The water that discharges at Mammoth Hot Springs in Yellowstone National Park is highly alkaline (contains a lot of dissolved CO2) and rich in calcium, but as the water cools, the calcium precipitates to form the white limestone terraces you see here. This limestone is known as tra ...[Read More]
Introducing the new EGU Bloggers!
Since it started, the EGU Blog Network has had great coverage of geochemistry, palaeontology and geoscience in global development, but what about the other fields in the geosciences? Well, over the past couple of months we’ve been seeking out some fantastic Earth science bloggers who are keen to share their knowledge, experiences and the latest research in their fields with you. They’ve put togeth ...[Read More]
Imaggeo on Mondays: Capping a volcano
This is Damavand Volcano, Iran. Its history is one of short bursts of eruptive activity followed by long periods of quiescence and while there are active fumaroles near Damavand’s summit, the volcano has been dormant for the past 1000 years. The cloud that encircles its peak is known as a cap cloud, so-called because these peculiar clouds form around high peaks, adding a flat white cap to mountain ...[Read More]
Geosciences Column: Tracing Toba
Large volcanic eruptions have a significant impact on the Earth’s climate as aerosols (including sulphur dioxide and water vapour), together with ash are released into the atmosphere and increase the amount of sunlight reflected back into space (the albedo). This increase in reflectance (or decrease in energy absorption) can cause widespread climatic cooling, known as a ‘volcanic winter’. However, ...[Read More]
GeoCinema Online: Hazards
In this week’s GeoCinema Online, we’re taking you to regions of the world that have experienced large eruptions in both the recent and distant past. These films take you through what it’s like to live in an active volcanic area or fault zone, from dealing with disasters, to how scientists are working towards better methods of earthquake and eruption forecasting: Mayon: The Volcano Princess I ...[Read More]
Imaggeo on Mondays: An Icy Illusion
This week’s Imaggeo on Mondays is brought to you by Robert Wills, a Caltech Ph.D. student studying how mountain ranges help set the global pattern of rainfall and how these rainfall patterns affect the erosional evolution of mountain ranges. Robert is also an avid photographer who particularly enjoys nature photography in the American Southwest. This is one of his finest snapshots from the area… W ...[Read More]
Imaggeo on Mondays: Volcanic Zones and Colourful Stones
This week’s Imaggeo on Mondays is Written by Yiming Wang, a paleoceanographer and paleolimnologist and keen photographer from the University of Kiel, Germany… Námafjall is a high temperature geothermal area by Lake Myvatn in northeastern Iceland, which known for its sulphurous mud springs. My fascination of Iceland began during a fieldwork expedition in March 2004 as I began to collect data for my ...[Read More]
GeoTalk: Encarnación Ruiz-Agudo
GeoTalk is a regular feature highlighting early career researchers and their work. Today we’re talking to Encarnación Ruiz-Agudo whose specialty lies in crystal growth and dissolution – the key to how rocks tell their stories! First, could you introduce yourself and let us know a bit about your current research? Also, what sparked your interest in crystallography and mineralogy? My name is Encarna ...[Read More]