Development to the Pearl River Delta of Southern China and the Influence of Chemical Weathering on Atmospheric CO2

This project is designed to reconstruct the chemical weathering history of Southern China and the evolution in erosion patterns driven by changes in monsoon intensity spanning the last 2 million years. The project is based around sampling sediment collected in a scientific borehole on the continental shelf of southern China in collaboration with colleagues at the China Geological Survey. Combination of radiogenic isotopes, major element chemistry and detrital zircon geochronology will be used to determine the changing erosion patterns within the Pearl River basin which is supplying the sediment to the continental shelf offshore the modern Pearl River Delta. These low latitude tropical continental shelves are increasingly understood to exert a major influence on global chemical weathering because large amounts of sediment are exposed to the atmosphere when orbitally driven climate change causes glaciation and sea level fall. Enhanced chemical weathering may remove further CO2 from the atmosphere driving further cooling. Conversely the opposite processes operate when the Earth warms and sea level rises. This important feedback needs to be better understood if we are to understand what controls the frequency and amplitude of climatic cycles as well as understanding how future sea level rise may impact the global climate.