# Deep-Sea Rocks Ignite in Lab

> Deep-sea rocks spontaneously combust when brought to surface, posing fire risks for ocean mining.
- Title: Deep-Sea Rocks Ignite in Lab · ScienceAlert | Shortify
- Summary: Deep-sea rocks spontaneously combust when brought to surface, posing fire risks for ocean mining. Deep-sea mineral samples can ignite upon exposure to air…
- Keywords: usgs, seafloor massive sulfide, spontaneous combustion, escanaba trough, deep-sea mining, hydrothermal deposits, marcasite, science, Deep-Sea, Rocks, Ignite, Lab
- Source: ScienceAlert — https://sciencealert.com/scientists-collected-deep-sea-rocks-they-spontaneously-caught-fire-in-the-lab
- Author: Carly Cassella
- Published: 2026-10-11T00:00:00+00:00
- Read time: 1 min
- Topics: usgs, seafloor massive sulfide, spontaneous combustion, escanaba trough, deep-sea mining, hydrothermal deposits, marcasite, science
## Deep-Sea Rocks Ignite
Scientists collected deep-sea mineral samples that spontaneously caught fire in lab tests.

> Scientists investigating the possibility of a 'gold rush' on the bottom of the ocean have hit upon an unforeseen 'landmine'.
## 2022 Lab Incident
Two metal-sulfide rock samples ignited at temperatures above 100 °c in 2022.

> In 2022, that happened to two samples of metal-sulfide rocks collected from the deep seafloor.
## USGS Warning
USGS warns deep-sea mining could trigger spontaneous fires due to rock oxidation.

> According to the USGS, this is a 'potential hazard that could merit special consideration if deep-sea mining of seafloor massive sulfide deposits moves forward'.
## Escanaba Trough
Researchers collected 57 samples from Escanaba Trough in Oregon, California EEZ.

> The Escanaba Trough sits in the US Exclusive Economic Zone (EEZ) off the Oregon, California border, where hydrothermal activity has created deep-sea deposits rich in metals.
## Combustible Minerals
Nanocrystalline marcasite causes rocks to self-heat and ignite when exposed to air.

> The self-combusting rocks were made mostly of nanocrystalline marcasite. This is a form of iron sulfide that appears to be especially unstable in the presence of oxygen.
## Mining Risks
Deep-sea mining could expose rocks to oxygen, causing fires on ships.

> If seafloor massive sulfide mining occurs, rocks brought to surface would experience conditions dramatically different from those on the seafloor, including exposure to oxygen and changes in temperature, pressure, and moisture.
## Key takeaway

Deep-sea mineral samples can ignite upon exposure to air, creating fire hazards for future ocean mining operations.