# Mantle Helium in Zambian Springs Confirms Active Lithospheric Rifting

- Published: 2026-11-10 09:40 UTC
- Section: Planet › Earth sciences
- Tags: Kafue Rift, mantle helium, lithospheric rifting, geothermal resources, helium exploration, African Rift System
- URL: https://realtech.media/news/rt-d3ecfb2a57c978b7262e6c6a_mantle_helium_in/

**Researchers measured mantle helium and carbon signatures in the Kafue Rift, indicating active lithospheric extension and gas potential.**

![Mantle Helium in Zambian Springs Confirms Active Lithospheric Rifting](https://realtech.media/media/2026/11/14b86fbbe46b15cf.webp)
*science-et-vie.com*

Geochemical analysis of hydrothermal springs in Zambia has provided the first chemical evidence of an active lithospheric rift zone connecting the East African Rift System to Namibia, according to a study published in Frontiers in Earth Science. The research team sampled spring gases across the Kafue Rift, identifying mantle-derived fluids rising to the surface along crustal-scale fault networks [1].

Hydrothermal gases sampled within the boundary faults showed helium isotope ratios of 3He/4He = 0.14–0.17 R/Ra and carbon isotope values of δ13C(CO2) = −3.9‰ [1]. These values reveal a clear mantle signature accompanied by mobilized crustal nitrogen ranging from 84.4% to 97.6% and elevated 4He concentrations between 0.4% and 2.3% [1]. Control samples taken from active hydrothermal groundwaters outside the rift boundary faults contained no isotopic evidence of mantle-derived helium or carbon dioxide [1].

## Tectonic Implications

The observed isotopic compositions and spatial patterns closely resemble early-stage rifts within the more thermally mature East African Rift System [1]. Together with low-level seismicity and previous geophysical observations, these geochemical data confirm the presence of early-stage lithospheric rifting across the region [1]. The findings demonstrate that deep fault systems cut through the continental lithosphere, channeling deep advective fluid flow to the surface [1].

## Resource Potential

The authors highlighted significant economic potential along these active central African fault systems [1]. The combination of mantle heat flow, advective transport along crustal faults, and groundwater trapping mantle CO2 without substantial fluid dilution suggests favorable conditions for geothermal energy development [1]. Furthermore, the elevated concentrations of crustal 4He, along with prospects for hydrogen exploration, point to commercially viable gas deposits within the region [1].

## Sources

1. [Frontiers in Earth Science](https://doi.org/10.3389/feart.2026.1799564)
2. [science-et-vie.com](https://www.science-et-vie.com/nature-et-environnement/en-zambie-des-bulles-de-gaz-dans-des-sources-chaudes-trahissent-la-naissance-probable-dune-nouvelle-limite-de-plaque-tectonique-240328.html)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-d3ecfb2a57c978b7262e6c6a_mantle_helium_in/