Category Archives: tectonics

The Napa Valley quake, and why California is (geologically) not part of America at all.

In the early hours of Sunday morning, the Napa Valley region north of San Francisco was shaken by a magnitude 6 earthquake, the largest to hit this region since the magnitude 6.9 Loma Prieta earthquake in 1989. An earthquake in … Continue reading

Categories: earthquakes, tectonics

Reconstructing ocean spreading when half your record is now in the mantle (or: a plug for my new paper)

If you’re studying the last 100 million years or so of plate tectonics, the history of sea-floor spreading recorded by the magnetic stripes that parallel and extend away from the Earth’s ocean ridges is a key source of information. Each … Continue reading

Categories: geology, geophysics, palaeomagic, tectonics

Antarctica field log: Penguin Island? Surely you mean Volcano Island!

But yes, there were penguins too. Continue reading

Categories: Antarctica, outcrops, photos, tectonics, volcanoes

Scenic Saturday: our stripy oceans, explained 50 years ago today!

A slightly different Scenic Saturday this weekend, as we celebrate an important milestone in geological science: a look at the South Pacific through a geophysical lens. The colours on this map show fluctuations in the Earth’s magnetic field produced by … Continue reading

Categories: geology, palaeomagic, tectonics

In large earthquakes, the Earth moves for almost everyone

The Global Positioning System has completely revolutionised how geologists study the deformation of the Earth. If you leave a GPS receiver in a fixed location for days, months and years, it is precise enough to measure motions on the millimetre … Continue reading

Categories: earthquakes, paper reviews, tectonics