Pogonophores are deep sea worms that thrive in dark, deep sea conditions thanks to the presence of symbiotic bacteria. The bacteria are chemoautotrophic, that is, they fix carbon through oxidation processes, rather than using light to fix it, as is the case for photosynthesis. By utilising oxygen in the water, the bacteria can oxidise compounds such as hydrogen sulphide in order to fix carbon. The ...[Read More]
Imaggeo on Mondays: Curl up under a peat blanket
Rannoch Moor is the largest area of unbroken (no houses, no roads) blanket bog in the United Kingdom. Blanket bogs – as their name suggests – blanket the ground in an extensive layer of peat. They form in regions where there is high rainfall and comparatively little evapotranspiration. These waterlogged conditions are found throughout much of the northern hemisphere, and allow blanket bogs to form ...[Read More]
Geosciences Column: Dating a bivalve
Just as the rings on a tree can be used to determine its age, the bands on a bivalve’s shell can tell us the how long it’s been around for. Warm, food-filled waters lead to greater growth in the summer and low plankton abundance (the principle food source for filter-feeding molluscs) leads to limited growth during the winter months – hence the banding. But pinning down the age of a bivalve m ...[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]