Sumatra - IODP map

Sediments tell a tsunami story.

Plate-boundary fault rupture during the 2004 Sumatra-Andaman subduction earthquake extended closer to the trench than expected, increasing earthquake and tsunami size. International Ocean Discovery Program Expedition 362 sampled incoming sediments offshore northern Sumatra, revealing recent release of fresh water within the deep sediments. Thermal modeling links this freshening to amorphous silica dehydration driven by rapid burial-induced temperature increases in the past 9 million years. Complete dehydration of silicates is expected before plate subduction, contrasting with prevailing models for subduction seismogenesis calling for fluid production during subduction. Shallow slip offshore Sumatra appears driven by diagenetic strengthening of deeply buried fault-forming sediments, contrasting with weakening proposed for the shallow Tohoku-Oki 2011 rupture, but our results are applicable to other thickly sedimented subduction zones including those with limited earthquake records. More...


Campi Flegrei (Italy) volcano eruption possibly closer than thought.

The Campi Flegrei volcano in southern Italy may be closer to an eruption than previously thought according to new research at UCL and the Vesuvius Observatory in Naples. The volcano has been restless for 67 years, with two-year periods of unrest in the 1950s, 1970s and 1980s causing small, local earthquakes and ground uplift. Similar unrest occurred over 500 years ago, when it took a century to build up to an eruption in 1538. More...

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Precambrian Research Group

The Precambrian is the informal name for the first 90% of Earth history during which life began its incredibly long journey towards biological complexity. 

This journey culminated in the appearance and diversification of animals between about 750 and 540 million years ago. Sedimentary rocks become increasingly scarce the further back in time one looks. For this reason, Precambrian studies are multidisciplinary by necessity, piecing together clues from a range of fields: geochemistry, palaeobiology, biochemistry, sedimentology, genetics and a range of earth system models (atmospheric, ocean circulation, climate and biogeochemical).

Our research group primarily uses the chemical, mineral and isotopic composition of sedimentary rocks to reconstruct earth system evolution during the two billion year interval from the end of the Archaean Eon (about 2500 million years ago) to the beginning of the Phanerozoic Eon (about 540 million years ago). During this Proterozoic Eon, extraordinary perturbations occurred to our planet’s surface environment. Some disturbances were extreme but transient, such as the ‘Snowball Earth’ intervals of global glaciation. Others caused irreversible changes that shaped the modern earth system, such as the ‘Great Oxidation Event’ and the ‘Neoproterozoic Oxygenation Event’ without which we would not be here today.