Author Archives: Chris Rowan

Older than the solar system

As Carl Sagan once said, “we are made of star stuff“: and here some of it is; mineral grains formed around distant suns, hundreds of millions of years before our solar system was born. These grains of silicon carbide were … Continue reading

Categories: deep time, geology, planets

Can we detect plate tectonics on exoplanets?

As celebrated in this Ars Technica piece, the 2010s was ‘the decade of the exoplanet’. Largely thanks to the Kepler telescope, the past ten years has seen an explosion in exoplanet discoveries. More than 4000 planets have now been identified orbiting other stars, … Continue reading

Categories: geology, planets, tectonics, volcanoes

New sonar data from around Anak Kratatau constrain size of December 2018 collapse

BBC story here. These data indicate a smaller collapse, but also a shallower failure plane than expected, which allowed that smaller volume to still generate a devastating tsunami. Basically, when modelling this, different combinations of slide volume and failure angle … Continue reading

Categories: geohazards, geophysics, volcanoes

Oxygenation of Earth’s atmosphere may not have required a trigger event after all

In Earth history, there have been 3 abrupt jumps in atmospheric oxygen. A evolutionary or tectonic trigger is usually invoked, but a new study just published in Science suggests all you need is gradual oxidation of earth’s surface plus feedbacks … Continue reading

Categories: Archean, climate science, deep time, geochemistry, geology, Palaeozoic, past worlds, Proterozoic, society

How long was the last magnetic reversal – and why might subducting slabs have had a say in what it looked like?

A new paper on the chronology of the last magnetic reversal concludes it took 20,000 yrs, and there were two distinct excursions – where the field becomes weak and disorganized, but it recovers without reversing polarity – before the main event about … Continue reading

Categories: geology, palaeomagic, paper reviews, rocks & minerals