Tectonics and surface effects of the supercontinent Columbia |
| |
Authors: | John JW Rogers M Santosh |
| |
Institution: | aDepartment of Geological Sciences, University of North Carolina at Chapel Hill, NC 27599-3315, USA;bDepartment of Natural Environmental Science, Faculty of Science, Kochi University, Kochi 780-8520, Japan |
| |
Abstract: | Assembly of the supercontinent Columbia at about 1.85–1.90 Ga coincided with several events that affected the entire earth. The oldest worldwide network of orogenic belts formed at the same time. Although some granite–granodiorite (GG) suites had formed earlier, the GG suites became common in the 1.8–1.9 Ga orogenic belts. These suites succeeded the older tonalite–trondhjemite–granodiorite (TTG) suites, which were not produced after 1.8 Ga. Changes on the earth's surface at 1.8–1.9 Ga include rapid increase in the concentration of oxygen in the atmosphere and oceans and probably the evolution of eukaryotes. All of these surface changes occurred as Columbia accreted, and the assembly of Columbia may have contributed to the drastic changes in the earth's surface environment as well as to the evolution of primitive life forms. |
| |
Keywords: | Supercontinent Tectonics Life evolution Surface processes Columbia |
本文献已被 ScienceDirect 等数据库收录! |
|