# Subduction-zone rock erosion linked to the Cambrian Explosion 540 million years ago

- Published: 2026-11-07 22:24 UTC
- Section: Planet › Earth sciences
- Tags: Cambrian Explosion, continental arcs, subduction weathering, phosphorus flux, marine oxygenation, isotope analysis, Guangzhou Institute of Geochemistry
- URL: https://realtech.media/news/rt-b308061cafee10488c2258bc_subduction_zone_rock/

**Geochemical records show intense weathering of juvenile volcanic arcs boosted marine nutrients and oxygen during animal diversification.**

![Subduction-zone rock erosion linked to the Cambrian Explosion 540 million years ago](https://realtech.media/media/2026/11/a732eb933bc58c8d.webp)
*scinexx*

Geochemists from the Guangzhou Institute of Geochemistry analyzed sedimentary cores from the South China Yangtze Block to determine how tectonic shifts influenced the early Cambrian biosphere [1]. In their findings published on nature.com, the authors integrated lithium and osmium isotope records with existing strontium data, revealing that fast-eroding continental volcanic arcs delivered a massive flux of nutrients into early oceans between 540 and 515 million years ago [1].

## Shifts in weathering regimes

The isotope measurements documented a distinct transition in weathering dynamics during the Ediacaran–Cambrian transition [1]. Between roughly 540 and 525 million years ago, seawater chemistry captured signatures of intense erosion dominated by juvenile, mantle-derived rocks from continental volcanic arcs along the active margins of Gondwana [1]. After 525 million years ago, this shifted toward clay-forming incongruent weathering of ancient continental crust [1]. The researchers noted that subduction zones thickened the crust, triggered regional uplift, and generated elevated volcanic carbon dioxide emissions that sustained a warm greenhouse climate [1].

## Nutrient influx and oxygen buildup

According to the authors, juvenile arc rocks typically contain 1.5 to 2 times more phosphorus than average continental crust and are prone to rapid denudation [1]. The enhanced erosion of these phosphorus-rich volcanic materials substantially increased oceanic nutrient levels, which stimulated primary marine productivity [1]. The resulting acceleration in organic carbon burial prevented oxygen from being consumed in back-reactions, fostering the prolonged atmospheric and oceanic oxygenation required for early animal diversification [1].

## Sources

1. [nature.com](https://www.nature.com/articles/s41467-025-64253-w)
2. [scinexx](https://www.scinexx.de/news/geowissen/hat-verwitterndes-vulkangestein-vor-540-millionen-jahren-einen-artenboom-ausgeloest)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-b308061cafee10488c2258bc_subduction_zone_rock/