Predicting the behavior of volcanic systems has historically been a challenge of indirect observation. While surface monitoring-such as seismology and gas emissions-provides clues, the internal chemical evolution of a magma chamber remains largely opaque. This gap in data creates significant risks for the nearly 10% of the global population living within 100 km of active volcanoes, and it complicates decisions for civil protection agencies and local governments tasked with evacuation planning and land-use regulation.
Teresa Ubide, a volcanologist at the University of Queensland, is bridging this gap by utilizing high-resolution spectroscopy to treat minerals as chronological records. “Even if Jules Verne envisioned it, accessing the inner guts of the volcano physically is impossible so far,” Ubide says. By analyzing the micro-structures of crystals, she is developing a method to forecast eruptions and locate the critical minerals essential for the global energy transition-work that feeds directly into how authorities implement national critical minerals strategies and long-term climate targets.
Decoding the Magmatic Plumbing System
The focus of this research is clinopyroxene, a variety of crystal that acts as a geochemical archive. These crystals grow in concentric layers, capturing the chemical state of the magma at different points in time. “They grow sequentially, like tree rings, and you see changes in the magmatic environment. The rim of the crystal-the last growth ring-is going to record what happens just before the eruption,” Ubide says.
The scale of this analysis is infinitesimal. “These crystals are the size of a chickpea if you’re very lucky-more often a lentil or grain of salt. The growth zones are microscopic. And you can analyze them with lasers, like we use for eye surgery. So we build this idea of how the plumbing system inside the volcano works, as if opening a doll’s house.”
A critical discovery involves chromium concentration. When 2D maps of clinopyroxene show a sharp increase in chromium in the outermost rims, it signals the arrival of primitive magma from the mantle. This injection often serves as the catalyst that tips a volcanic system toward an eruption. That kind of signal can, in principle, be integrated into operational volcano observatories to refine alert levels and the timing of protective measures under frameworks such as the Sendai Framework for Disaster Risk Reduction. The same technique was applied during the 2021 La Palma eruption, where real-time analysis of magmatic liquid showed chromium oxide concentrations leveling off roughly two weeks before the event ended, indicating a slowing of new magma influx.
High-Resolution Chemical Mapping
The precision of this work relies on laser ablation inductively coupled plasma quadrupole mass spectrometry (LA-ICP-MS). Unlike traditional mass spectrometry, which requires the total destruction of a sample, LA-ICP-MS allows for spatial resolution across a single crystal, turning each grain into a small but information-rich map of a volcano’s interior history.
| Feature | Traditional Mass Spectrometry (MS) | LA-ICP-MS |
|---|---|---|
| Sample Preparation | Rock crushed to powder and dissolved in solution | Intact crystal analysis via laser desorption |
| Resolution | Bulk average of the entire sample | Microsampling down to a few micrometers |
| Data Output | Single chemical snapshot | 2D chemical timeline/elemental distribution |
| Preservation | Sample is consumed/destroyed | Sample remains largely intact for further study |
“The laser allows you to microsample: very tiny parcels, down to a few micrometers,” Ubide says. This capability allows researchers to create visual timelines of geologic events that occurred over millennia, providing a level of temporal detail that conventional monitoring networks cannot easily match.
A map of a clinopyroxene crystal, collected from Mount Etna, shows an intense accumulation of chromium (orange) in its outer layer just prior to eruption.
Credit: Teresa Ubide
Critical Minerals and the Energy Transition
Beyond hazard mitigation, this spectroscopic approach has significant implications for the critical minerals market. Copper is central to the decarbonization of the global economy, acting as the primary conductor for electrification. However, supply is expected to lag behind the exponential growth of green infrastructure, a gap that is already shaping national resource policies and industrial strategies.
- Electric Vehicles (EVs): Require upwards of 50 kg of copper per unit.
- Wind Energy: A single wind turbine requires nearly 5 metric tons.
- Grid Infrastructure: Massive upgrades to electrical grids for renewable integration demand unprecedented volumes of copper.
“[Copper]’s such a good conductor of electricity and heat, it’s the number 1 thing we need,” Ubide says. “One electric car needs more than 50 kg of copper; one wind turbine needs almost 5 metric tons.”
Copper deposits often form in hydrothermal systems associated with volcanoes that did not erupt. “All magmas have a little bit of copper, but it’s very, very rare” for it to accumulate. If the magma reaches a point where it can release volatile gases without erupting, it can heat groundwater and precipitate metals into fractured rocks. “You want the volcano not to erupt because you lose the copper to the atmosphere,” Ubide says. For governments under pressure to secure domestic supplies of critical raw materials while tightening environmental regulation, knowing where such deposits are most likely to form is not just a scientific challenge but a strategic one.
Mobile Exploration and Geological Intelligence
While clinopyroxene is a marker for eruptions, plagioclase (a type of feldspar) is more common in the silica-rich regions where copper typically accumulates. By analyzing plagioclase, researchers can identify high-probability drilling sites without the need for invasive, wide-scale exploratory mining, giving regulators and communities more leverage to demand targeted, lower-impact projects.
This has led to the conceptualization of mobile geological intelligence. “[If] we get to the point where we can analyze the plagioclase, and if the plagioclase gives you reliable information, you could, in the future, envision a van where you go around the region, get the sample with your hammer, zap the plagioclase, and say, green light, let’s drill here! Or red light, let’s move on,” Ubide says. In practice, that kind of field-deployable analytics could sit alongside permitting rules and community consultation, offering real-time evidence on whether a proposed site is worth the regulatory and social cost.
This shift toward precision mineral exploration reduces the environmental footprint of mining and increases the efficiency of resource recovery. This scientific progress is often supported by ground-level collaboration. Ubide highlights the importance of indigenous and local knowledge, such as a guide in Indonesia who led her to a lahar deposit. “The samples we got there-stunning,” she says.
Reflecting on the collaborative nature of the field, she notes, “Oh, if you’re interested in crystals, this lahar deposit has lots.” By combining advanced LA-ICP-MS technology with multidisciplinary partnerships that span local communities, academia and government agencies, the research transforms raw geological data into actionable intelligence for both public safety and industrial sustainability. “We made long-lasting human connections.”
