Category Archives: impacts

Scars, acne and others: circles on the ground

Looking is never just looking. When we gaze at something, we are not passive recipients of an image, instead our brain is constantly looking for patterns. If you are drifting over the earth, whether as an astronaut or via Google Maps then … Continue reading

Categories: Great Geology in Google earth, impacts

A world without subduction

The greatest achievement of the generation of Earth Scientists now retiring is the concept of plate tectonics. The insight that the earth’s surface is made up of rigid plates that move has shed light on all aspects of Earth Science, … Continue reading

Categories: eclogites, impacts, metamorphism, subduction, tectonics

Radioactivity and the earth (and moon?)

We tend to think of radioactivity as an artificial thing; some argue that the first nuclear explosions in 1945 should mark the start of a new human-dominated geological epoch called the Anthropocene. These man-made explosions have left distinctive radioactive traces … Continue reading

Categories: geochemistry, impacts

The Great Ordovician meteor shower

Between Mars and Jupiter, 470 million years ago, there was a massive collision between two 100km-sized chunks of rock – this solar system’s biggest bang of the last billion years. It created a massive cloud of smaller fragments. Some of … Continue reading

Categories: History, impacts, sediments