The Earth's Deep Carbon Cycle. The climate change debate has focused scientific attention on Earth’s exogene carbon-cycle. However, Earth has another, much deeper carbon-cycle which is poorly understood. In addition to exerting a profound influence on atmospheric greenhouse gas concentrations over time scales from thousands to billions of years, it is critically important in many processes in the Earth’s deep mantle. The major means by which the deep carbon-cycle is replenished is via subduction ....The Earth's Deep Carbon Cycle. The climate change debate has focused scientific attention on Earth’s exogene carbon-cycle. However, Earth has another, much deeper carbon-cycle which is poorly understood. In addition to exerting a profound influence on atmospheric greenhouse gas concentrations over time scales from thousands to billions of years, it is critically important in many processes in the Earth’s deep mantle. The major means by which the deep carbon-cycle is replenished is via subduction of carbonate-bearing oceanic crust. The project proposes a high-pressure experimental and field-based program to understand the fate of this carbonate during its journey from the exosphere, through subduction zones and into the deep mantle.Read moreRead less