Organic carbon cycling and black shale deposition: an Earth System Science perspective

Abstract

Earth has a prolonged history characterized by substantial cycling of matter and energy between multiple spheres. The production of organic carbon can be traced back to as early as ∼4.0 Ga, but the frequency and scale of organic-rich shales have varied markedly over geological time. In this paper, we discuss the organic carbon cycle and the development of black shale from the perspective of Earth System Science. We propose that black shale depositions are the results of interactions among lithospheric evolution, orbital forcing, weathering, photosynthesis, and degradation. Black shales can record Earth's oxygenation process, provide petroleum and metallic mineral resources, and reveal information about the driver, direction, and magnitude of climate change. Future research on black shales should be expanded to encompass a more extensive and more multi-dimensional perspective.

Deep carbon recycling viewed from global plate tectonics

“…The integrated mountain building-related processes are fundamental to nutrient cycling from continents to oceans and thus the evolution of life [e.g. 22 , 23 ]. Overall, convergent plate margins link up the deep and surface Earth systems, dominate the long-term recycling of volatile elements (especially carbon), and are central to the stabilization of the physico-chemical basis that supports Earth's habitability.…”