Pillow-palagonite complex forming as a result of hot lava entering a former river channel or lake in the Columbia River Flood Basalt Province, Washington State, USA (c. 15 My). Individual sediment packages were picked up from the bottom of the water body and trapped within the lava complex (see white arrow). Orange-brown palagonite is a type of clay which forms through the break-down of volcanic g ...[Read More]
Being a stratigrapher or not, there’s one stratum you have all trod upon if you ever went to the General Assembly (GA), without probably noticing it. The uppermost unit of EGU’s GA floor, a ca. 5 mm thick layer with a soft rubbery texture and peculiar light-grey colour, outcropping over the whole poster halls: Carpet! Yes, the focus of this post is the carpet draping the GA’s floor wit ...[Read More]
Delicate Arch is probably the most spectacular natural arch in Arches National Park, Utah. Delicate Arch is made of the Middle Jurassic Entrada Sandstone, which was deposited in various environmental settings, particularly beaches, tidal mudflats and deserts. Arches National Park attracts more than 1.5 million visitors per year.
Pollen – for many people rather an irritant across spring, summer and autumn when trees and flowers are in bloom. Individual pollen grains are between a few µm (micrometre, which is one thousandth of an mm) and >130 µm in diameter. This size range is impossible to see with the naked eye unless the pollen grains are clumped together, or when pollen is dispersed as powder into the air on a dry su ...[Read More]