Carbon mineralization is a natural CO2 sequestration process that converts CO2 gas into solid carbonate minerals at the Earth’s surface. Through the CarMA (Carbon Mineralization Analogues) research program, we look at sites where these reactions occur naturally to learn as much as we can about real-world carbonate formation processes, CO2 storage security, fluid-mineral reactions, weathering rates, and other natural phenomena that can be used to inform our research and development of accelerated carbon mineralization technologies. These analogue sites can also be great places to test monitoring and verification equipment that will eventually be used at mines or other sites that can employ carbon mineralization to sequester CO2.
Primarily, natural analogues are places that contain various ultramafic rocks. Ultramafic rocks are formed in the mantle and have reached the earth’s surface through uplift or intrusion, and contain high abundances of magnesium and iron. We focus on these rocks because they have a high potential to react with CO2 to form carbonate minerals and reduce greenhouse gases.
Every CarMA site is unique and there are different reasons why our team may be drawn to study them. Some may be better for studying hydrothermal alterations of ultramafic rock, and how this affects reactions with CO2. Some display microbially-mediated dissolution and precipitation processes. Some are more suitable for analyzing the long-term stability of CO2 as carbonate minerals. All of these allow us to observe natural systems to enhance our understanding of carbon mineralization as a strategy to capture and safely store CO2.
CarMA is composed of various research projects, both in Canada and around the world.
Atlin carbonate playas (BC, Canada)
The town of Atlin, BC hosts several unique geologic features called carbonate playas. The playas are formed when CO2-rich groundwater flows through the underlying ultramafic bedrock and emerges at the surface. Reactions between aqueous CO2 and the ultramafic bedrock produces hydromagnesite and magnesite at the surface, which are types of carbonate minerals. This site offers insights into naturalcarbon mineralization, microbially driven dissolution of the ultramafic bedrock and subsequent carbonate precipitation, and conditions similar to mine tailings on which to test monitoring techniques and protocols for measuring real-time CO2 fluxes in passive and active carbon mineralization settings.
Oman Drilling Project (Oman)
The Oman Drilling Project is a large collaborative research initiative involving scientists and organizations from all over the world, whose goal is to investigate the Samail Ophiolite. An ophiolite is a piece of oceanic crust and upper mantle that was uplifted and exposed at the Earth’s surface, and this particular ophiolite is one of most studied examples in the world due to its size and exposure. CarbMin’s interest lies in understanding the geological processes leading to the formation of fully carbonated mantle rock, found at the base of the Samail Ophiolite, a natural example of carbon mineralization in ultramafic material.
To learn more about the Oman Drilling Project, click here.
Swift Creek Landslide (WA, USA)
The Swift Creek landslide in northern Washington is a naturally occurring landslide that is made up of serpentinite rock and soil that is moving downhill and weathers rapidly. This sustained movement continually exposes new, reactive material to the atmosphere. These ultramafic sediments take up as much as 2 kg CO2/m2 each year and are mineralogically and texturally analogous to mine tailings from serpentinite hosted ore deposits. Thus, this landslide is an excellent, easily accessible natural analogue that we use to test equipment to accurately measure rates of CO2 sequestration into ultramafic materials.