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How did supercontinent formation affect volcanic activity and Precambrian climate?

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A detailed geologic time scale chart displaying Earth's history from the Hadean Eon over 4.5 billion years ago to the present, organized by eons, eras, periods, epochs, and ages with color-coded columns and corresponding dates in millions of years. — Precambrian The stratigraphic chart of geologic time.

During the Precambrian, the formation of supercontinents significantly influenced both volcanic activity and global climate patterns.1

Impact on Volcanic Activity

When supercontinents formed—notably at 2.5 billion, 2.1 to 1.8 billion, and 1.0 billion to 900 million years ago—the total number of volcanoes on Earth was limited. During these periods, there were fewer island arcs and the total length of oceanic spreading ridges was relatively short. This reduction in tectonic activity resulted in lower emissions of carbon dioxide, a potent greenhouse gas.1

Impact on Climate

The decrease in volcanic CO₂ emissions during supercontinent assembly weakened the greenhouse effect, which contributed to lower global surface temperatures and facilitated extensive glaciations. Conversely, during times of continental breakup, increased rates of seafloor spreading and subduction led to higher volcanic CO₂ output, which warmed the Earth and prevented glaciation.1