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More than 90% of Earth's continental crust is made up of silica-rich minerals, such as feldspar and quartz. But where did this silica-enriched material come from? And could it provide a clue in the search for life on other planets? Conventional theory holds that all of the early Earth's crustal ingredients were formed by volcanic activity. Now, however, McGill University earth scientists Don Baker and Kassandra Sofonio have published a theory with a novel twist: some of the chemical components of this material settled onto Earth's early surface from the steamy atmosphere that prevailed at the time. First, a bit...

A tiny 4.4-billion-year-old crystal has been confirmed as the oldest fragment of Earth's crust. The zircon was found in sandstone in the Jack Hills region of Western Australia. Scientists dated the crystal by studying its uranium and lead atoms. The former decays into the latter very slowly over time and can be used like a clock. The finding has been reported in the journal Nature Geoscience. Its implication is that Earth had formed a solid crust much sooner after its formation 4.6 billion years ago than was previously thought, and very quickly following the great collision with a Mars-sized body...

Scientists are to sail to the mid-Atlantic to examine a massive "open wound" on the Earth's surface. Dr Chris MacLeod, from Cardiff University, said the Earth's crust appeared to be missing across an area of several thousand square kilometres. The hole in the crust is midway between the Cape Verde Islands and the Caribbean, on the Mid-Atlantic Ridge. The team will survey the area, up to 5km (3 miles) under the surface, from ocean research vessel RRS James Cook. The ship is on its inaugural voyage after being named in February. Dr MacLeod said the hole in the Earth's crust...