Category Archives: deep time

Remagnetisation spoils the paleomagnetic party again

Posted on April 10, 2020 by Chris Rowan

Did the Earth have a magnetic field before 3.5 billion years ago? Previous paleomagnetic studies of the world’s oldest mineral grains – the Jack Hills zircons, which have maximum ages of 4.4 billion years – claimed that tiny inclusions of … Continue reading →

Categories: Archean, deep time, palaeomagic, paper reviews

Older than the solar system

Posted on January 22, 2020 by Chris Rowan

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

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

Posted on December 14, 2019 by Chris Rowan

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

Earthquake prediction is a fool’s errand

Posted on May 13, 2018 by Chris Rowan

If you want to make earthquake scientists jumpy, all you need to do is ask, "can you predict the next earthquake?" In fact, any variation on the theme of ‘earthquake’ and ‘prediction’ will do – unless it is one which … Continue reading →

Categories: deep time, earthquakes, geohazards, geology, ranting, society