All posts by LL

Rumbles in the Alps reveal rockslides

The ricochet of a rock fall resonates in the mind of anyone who has heard it. But it also sets off subterranean waves detectable by far-off seismic stations — and now researchers are using those signals to remotely model rockslides.

Franziska Dammeier, an engineering geologist at the Swiss Federal Institute of Technology in Zurich, and her colleagues linked five metrics of seismic waves to five physical characteristics of rockslides: volume, runout distance (how far the rocks travel), drop height, potential energy and the angle of reach. The researchers reported their model last week in the Journal of Geophysical Research. Continue reading Rumbles in the Alps reveal rockslides

Banded Iron Formations Have Microbial Link?

A pair of mineral clues recently found in a fossil seafloor may be signs that ancient bacteria helped create banded iron formations — Precambrian-aged sedimentary rocks known for their vibrant, reddish- brown-colored thin layers — that researchers use to reconstruct ancient interactions between the atmosphere, the ocean and the seafloor.