Cratons are pieces of continents that have been stable for a over a billion years. As earth’s plates drift along, mountains periodically rise and fall, plate boundaries appear and disappear. But cratons are like great-grandmothers at family gatherings, while younger crust moves excitedly around them, they sit quietly, occasionally remarking on how different things were when… Continue reading Cratons – old and strong
Category: mountains
Erosion makes mountains beautiful
The thing that makes mountains so beautiful and fascinating,is not so much their height as their steepness. Climbers and trekkers flock to the High Himalaya, not to get altitude sickness but for the grandeur of the landscape, the experience of seeing views that require you to lift your head up. Mountains are created by deep-seated… Continue reading Erosion makes mountains beautiful
Mantle support of topography – a swell idea
Why are some bits of the earth higher than others? Finding mountains near plate boundaries is easy to explain – various forms of plate collision cause the crust to thicken and the surface to rise. What about Southern Africa? Reaching a high point of 3473m, most of Southern Africa is a high plateau. It is… Continue reading Mantle support of topography – a swell idea
Sherlock Holmes and the case of the detrital zircon
The October copy of the journal Geology contains a paper that made me think of Sherlock Holmes. That doesn’t happen very often. One of the fictional detective’s many skills was the ability to get important insights from the sediment found on shoes. The paper “Detrital zircon record and tectonic setting” looks at ancient sediments and proposes… Continue reading Sherlock Holmes and the case of the detrital zircon