MagNetZ With Joe Meert (2022/11/02) - How well do we know the Makeup of Proterozoic Supercontinents?
Channel: MagNetZ
Date: 2022-11-10

How well do we really know the Makeup of Proterozoic Supercontinents?

The video is also available for download at: https://earthref.org/ERDA/2541/
and can be referenced with the doi: 10.7288/V4/ERDA/2541

Title: How well do we really know the Makeup of Proterozoic Supercontinents?
Author: Joe Meert from the University of Florida, USA

At least two large continental agglomerations were proposed in the Proterozoic. The younger Rodinia supercontinent began its accretional phase perhaps as early as 1.3 Ga, is thought to have reached maximum packing around 0.85 - 0.9 Ga and dispersed between 0.8 - 0.6 Ga. Rodinia was preceded by the Paleo-Mesoproterozoic supercontinent called Columbia or Nuna. Our knowledge of Columbia assembly is complicated by the fact that many of its constituent elements were themselves undergoing multi-phase assembly during the Paleoproterozoic. Columbia assembly therefore was a protracted process beginning as early as 2.1 Ga and likely not reaching maximum packing until sometime after 1.6 Ga with breakup ~1.4 - 1.3 Ga. These two supercontinents are associated with unique intervals of Earth history. The so-called ‘boring billion’ from 1.8 - 0.8 Ga appears to be an inappropriate label if two large landmasses assembled and dispersed during that interval. The Cryogenian Snowball Earth intervals coincide with the breakup of Rodinia and perhaps the early rise of metazoan life. In this talk I will concentrate on the paleomagnetic data (or lack thereof) constraining the geometry of these two supercontinents.

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00:00 - Intro
00:46 - Presentation
35:05 - Questions
46:27 - Announcements