Project Vesta

Turning the tide on climate change via the
accelerated weathering of olivine on beaches.

Project Vesta

Project Vesta is a project to sequester carbon dioxide (CO2) by accelerating the weathering of a type of rock called olivine. When olivine interacts with water and the CO2 dissolved in it, it creates a bicarbonate solution that marine animals like corals use in their shells. The CO2 remains locked in that form and eventually settles as sediment or turns to limestone rock on the sea floor.

Olivine is a volcanic rock and one of the most abundant minerals on earth, making up over 50% of the upper mantle. It is also cheap, at less than $25 per ton, and each 1 ton of olivine that breaks down from weathering, sequesters 1.25 tons of CO2.

The issue is that the vast reserves of it are all underground. So our plan is to mine olivine and accelerate its weathering by using wave motion to tumble the rock. We imagine a global network of green sand beaches to turn the tide on carbon dioxide induced climate change.

Sequestration Math

1 ton of olivine weathered = 1.25 tons of CO2 sequestered.

Rock Volume

7km^3 of olivine yearly

Beach Area Needed

2% of the world's shelf seas

Price Per Ton Of CO2 Sequestered

< $25 per ton including mining, milling and transport costs.

Weathering Science

Step 1: Olivine (Mg2SiO4) + Water (4 H2O) →
2 (Mg)² + H4SiO4 + 4 OH-

CO2 Consumed

Step 2: 4 OH- + Carbon Dioxide (4 CO2) → Bicarbonate (+4 HCO3-)

"Spreading of olivine in the world’s 2% most energetic shelf seas can compensate a year’s global CO2 emissions and counteract ocean acidification against a price well below that of carbon credits...Olivine and other (ultra)mafic minerals in high-energy shallow-marine environments weather fast. Their application can make a significant contribution in the fight against climate change. The counteracting effect on ocean acidification is immediate. Large-scale spreading of olivine in shelf seas with adequate tidal currents and wave action can be started any moment."

Olaf Schuiling & P. L. de Boer
Professors of Geoscience, Utrecht University
Rolling Stones; Fast Weathering of Olivine in Shallow Seas For Cost-Evffective CO2 Capture And Mitigation of Global Warming and Ocean Acidification (2011)

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THREE MAJOR BENEFITS

The weathering of olivine in oceans offers 3 major benefits to the planet, simultaneously: (1) sequestering carbon, (2) deacidifying ocean water, and (3) fertilizing the ocean ecosystem.

01. Sequester

The earth permanently holds a majority of its CO2 deposits in rock, such as the limestone created by corals and other organisms through the use of calcium carbonate in their shells.

02. Deacidify

The resulting solution from the reaction of olivine, water and CO2 is alkaline and therefore works to combat ocean acidification by raising the pH level of water in the surrounding area.

03. Fertilize

A product of the olivine weathering reaction is silicate, which is the limiting factor for diatom populations. They are a type of plankton threated by climate change and which make up the base of many marine food chain ecosystems.

EARTH HISTORICALLY USES ROCK TO BALANCE & STORE CO2

Natural Cycle

For billions of years, the CO2 released from volcanic activity was kept in balance by the weathering of volcanic rock. However, when we add new sources of CO2, Earth’s natural process of exposing rock to weathering on geological timescales is too slow to counteract the increased CO2.
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Unnatural Cycle

The release of CO2 is now 40 times faster than Earth’s natural rate of CO2 sequestration from rock weathering. Fortunately, by increasing the amount of weatherable rock exposed to the environment, we can increase the rate of CO2 uptake.

WHERE IS THE EARTH'S CARBON?

99.9% of Carbon is in rock already!

Rock Is The Earth's Carbon Store

99.9% of carbon on Earth is currently in solid form as rock in Limestones, Dolomites and Sediments. Rock is the Earth’s natural and preferred location to store carbon. Our warming problems come from the gas form of carbon in the atmosphere as carbon dioxide (CO2). The CO2 in the atmosphere makes up only .004% of the total carbon on Earth though, and the extra CO2 added since the 1750s is only about a third of that. It only makes sense that we return this small fraction of excess carbon back into the same form that the overwhelming majority the planet’s carbon is stored in: rock.
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Removing Parts Per Million

The fraction of the world’s carbon as CO2 in the atmosphere is itself only at a level of about 400 parts per every 1,000,000 particles of the atmosphere. As visualized in the above image, with each of the 25,488 white dots representing a part of air, the blue circles represent the proportion of CO2 molecules as they were in the year 1750 (at 280 PPM), and the red circles are the extra CO2 molecules added from 1750 through 2008 (totaling 385 PPM) in the atmosphere. We are proposing to accelerate Earth’s own rock weathering reaction to pull those red circles out of the atmosphere and put them back underground with the rest of the carbon. When we look at it from this perspective, it suddenly appears to be a surmountable quantity of CO2 for us to remove.
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REBALANCING THE CARBON CYCLE

1. Carbon Release

Humans are already intervening in the carbon cycle by releasing higher volumes of CO2 than the natural carbon cycle can handle.

2. CO2 Interacts With Water

CO2 interacts with water to form carbonic acid. CO2 concentrations in the ocean also increase as atmospheric concentrations increase.

3. Converting CO2 to Bicarbonate

This is where we can intervene by increasing the amount of silicate rock exposed to water and CO2 to help balance and restore the carbon cycle. The weathering of this rock moves the carbon in CO2 out of the air/water and into the type of carbon used for animal shells. From there it eventually turns to sediment and rock.

OLIVINE IS THE IDEAL ROCK FOR REMOVING CO2 FROM THE ATMOSPHERE

Among Earth's Most Abundant Minerals

Olivine makes up more than 50% of the upper mantle. It forms from volcanic activity and is one of the most common minerals by volume. There are vast reserves close to the surface, all over the world, and it is inexpensive to acquire.

Commonly Known as Peridot

Most non-geologists will be more familiar with the gemstone quality version of olivine, known as peridot. It is typically green, but its color can vary depending on the exact chemical makeup of the rock.

Forsterite: The Magnesium Rich Olivine

With the chemical makeup of Mg2SiO4, this type of olivine is most suitable for weathering in the ocean. Even if all human CO2 emissions for 100 years were offset in the ocean by olivine, the magnesium content of the ocean would only rise from 1296 to 1296.6 ppm and the bicarbonate content from 42 to 45 ppm, which is within normal global ocean water concentration ranges.

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Rapidly Weatherable

Olivine is the most easily weatherable of the silicates and rapidly forms bicarbonate when it comes in contact with CO2 water and the molecules dissolved in it, binding the CO2 in solution.

Extremely Cheap

Olivine rock can be acquired on the market today for less than $25 per ton. As demand increases and new and larger olivine mines open, the price will go down significantly. Basic models on similar open pit rock mines demonstrate a price below $10.
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Highly Abundant

Olivine is found all over the world, with huge reserves in vast formations typically occurring near the surface. Significant quantities are sitting as waste piles on the property of old mines.
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1 TON OF OLIVINE WEATHERED = 1.25 TONS OF CO2 SEQUESTERED

1 Ton Olivine

1.25 Tons of CO2

OLIVINE WEATHERING REACTION

Weathering is the breakdown of rocks from contact with CO2, water, and organisms. When olivine interacts with ocean water and the CO2 dissolved in it, it undergoes a reaction that binds the carbon dioxide in bicarbonate, which is then used by animals, including corals, in their shells.

Those shells go on to settle in the sediment and eventually turn into limestone rock. Small and safe amounts of magnesium and silicate are left over from the reaction. The silicate is desperately needed by a crucial species of plankton known as diatoms, which themselves, further sink carbon.

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SPEEDING UP THE WEATHERING REACTION WITH MOTION

When olivine is stationary it can take a long time to weather because of a silica (H4SiO2) coating that builds up during the weathering reaction. However, when olivine is tumbled and kept in motion, it not only removes the coating but rapidly accelerates the weathering process by breaking the rock into smaller pieces, that themselves weather much more rapidly.

Stationary Olivine

The weathering reaction creates a silica (H4SiO4) coating around the remaining olivine material, represented here with solid yellow lines. When stationary, this coating dramatically slows down further weathering. Most calculations of olivine weathering rates assume the rock is stationary. But our plan is to remove that coating with motion. Notice how much smoother the rocks in the next picture look after just 3 days of motion in a tabletop shaker.

Mechanically Activated Olivine

When olivine is mechanically activated, such as when it is tumbled by waves on a beach or dragged along the seafloor by strong bed shear forces, the coating is continually destroyed, which allows the weathering reaction to proceed rapidly. This is shown above by the dashed yellow lines, but also notice the smoothness of the rocks after just 3 days of motion. The tumbling chips off small pieces of olivine that themselves then rapidly weather.

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Olivine Sand Beaches

In order to mechanically activate the olivine and prevent a buildup of silica, it has been suggested to utilize the constant tumbling motion of waves and the power of tidal forces.

The constant refreshing of water and high oceanic CO2 concentrations, combined with the wave motion, make beaches the ideal place to accelerate olivine weathering on a large scale.

Olivine sand beaches occur naturally near volcanoes, like this one in Hawaii. They are safe for humans and wildlife and our plan is to intentionally create more of them.

The "Seasaw"

This field study will show the real-world dissolution rate of olivine at the proposed beach deployment site.

Impact Beach

A beach deployment as a trial to demonstrate the concept and further test for safety before scaling up

Country Scale

Olivine beaches can scale so that individual countries with coastlines can offset their total CO2 output.

Regional Scale

Entire regions could collaborate to more efficiently scale up mining and distribution.

Global Scale

Olivine is located all over the world and a global effort would unite countries with varying resources, labor skills, and coastlines.

Phase I: The "Seasaw"

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1. Raise Funds for the "Seasaw" Tumble Tank

The rate of olivine dissolution is well established in surface rocks, in rivers, from mining piles and in lab conditions simulating ocean tumbling, but to calculate the exact rate in real-world conditions before we scale up, we will create a pilot project.
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Deploy "Seasaw"

The "Seasaw" will be deployed to a warm beach with tidal forces that mimic our projected beach deployment. One end of the tank faces the waves and the other rests on the shore. The tube is able to tilt back and forth like a seesaw. As waves arrive, they force the tank to tilt forward and as the tide recedes, it causes the tank to tilt back the opposite way.
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Monitor Dissolution Rate

The ends of the tube are open at the tops to block the rocks from leaving, but to allow the water to pass. Devices at both ends of the tube monitor the contents of the water and allow us to demonstrate the real-world rate of olivine dissolution.

Phase II: Impact Beach

The world's first intentional green sand beach. With each 1 ton of olivine added, sequestering 1.25 tons of carbon dioxide. Individuals and organizations would be able to sponsor the placing of olivine to offset their carbon footprint. This beach and its sister projects will prove our concept and become ecotourism destinations.

PHASE III: COUNTRY SCALE

The race to become the first carbon-neutral country is on and accelerated weathering of olivine is the only technique in existence that is scalable, financially viable, and can be started today.

Neutralize Emissions

As an example, Costa Rica has pledged to be carbon neutral by 2021, but each each citizen is responsible for approx. 1.6 tons of CO2 per year mostly from transportation. This equates to less than $30 per person of olivine. By lining the coasts of Costa Rica with 11.68m tons of olivine, they could be carbon neutral on schedule.

Opportunities Abound

Any country with warm waters and continental shelf seas has an opportunity for accelerated weathering. Costa Rica has a shoreline of 1,016 km on the Pacific side, most of which would be suitable for olivine weathering. Inland countries or those with non-optimal beaches could partner to provide olivine.

PHASE IV: REGIONAL SCALE

Working Together

Countries and specific regions with opportune, high-energetic marine environments could partner to offset their CO2. Part of the continental shelf between the Shetland Isles and France, known as the Southern Bight of the North Sea, has an ideal area of over 35,000 km^2.

Negative Emissions Initiative

A volume of just 0.35 km^3 of olivine grains, applied at 1 cm thickness to the accessible coastlines of countries adjacent to the Southern Bight (UK, France, The Netherlands, Belgium and Ireland), would offset about 5% of humanity’s yearly CO2 output. Yet these countries only contribute about 4% of the worlds CO2 emissions, so they would effectively all be carbon negative.

Unique Location

The Southern Bight is an exceptional project location, as the seafloor itself has strong enough bed shear stresses and currents to tumble olivine. In this region, beaches would not even be necessary. Ships could simply dump the 1.2 Gt of olivine directly in the water.

Borders are human created constructs that do not represent our interconnected planet and environment. Regions of the world could partner together to utilize the optimal geography where present, working on massive projects taking advantage of those countries with adequate coastlines and others with adequate olivine deposits.

PHASE V: GLOBAL SCALE

In order to offset all of humanity's yearly CO2 output, the world would need to distribute a volume of 7 km^3 of olivine across the 2% most tidally active shelf seas and beaches. Each of these red dots represents one or more olivine deposits. Neighboring countries would be encouraged to work together to efficiently allocate low-cost labor, olivine resources and shorelines. With a global effort this is possible, there are known mines for other minerals with excavated volumes of 25 km^3 and each year we mine about 10 km^3 of oil equivalents.

Global Workforce

A labor force of 1-1.5 million people is all that would need to be employed worldwide to mine enough olivine to offset all yearly anthropogenic CO2. That equates to 0.2% of mankind and is considerably less people than those involved in the coal mining and oil industry.

Economy of Scale

Today, crushed olivine can be purchased at the port of Rotterdam for about $25/ton. The costs of mining and milling olivine is only about $3-4 per ton (year 2000 prices). With transport and spreading, it is calculated that the cost per ton of CO2 captured by olivine could end up being less than $10.

Global Costs

Climate change is going to cost the world trillions of dollars in damage and lost economic value. For about $250 billion per year, however, the entire world can offset their CO2 output with olivine. This is meant to buy time for countries while they work to cease their CO2 release. Once countries are fully neutral, olivine can continue to be dumped in order to restore the climate back to pre-industrial CO2 levels.

  1. Rolling Stones; Fast Weathering of Olivine in Shallow Seas for Cost-Effective CO2 Capture and Mitigation of Global Warming and Ocean Acidification
  2. Mitigation of CO2 Emissions by stimulated natural Rock Weathering
  3. A geological perspective on global warming and the possibility of carbon dioxide removal as calcium carbonate mineral
  4. “This picture represents carbon dioxide in the atmosphere. Air is a mixture of gases. In this picture, air molecules are represented as white dots – 25, 488 of them. Their separation corresponds to the average separation of air molecules at sea level (about 11 molecule diameters). Carbon Visual’s Flickr
  5. Mitigation of CO2 Emissions by Stimulated Natural Rock Weathering
  6. Olivine against climate change and ocean acidification
  7. Cost Model for a 5,000 ton/day Open Pit Mine
  8. Carbon Dioxide Fixation within Mine Wastes of Ultramafic-Hosted Ore Deposits: Examples from the Clinton Creek and Cassiar Chrysotile Deposits, Canada
  9. Rolling Stones; Fast Weathering of Olivine in Shallow Seas for Cost-Effective CO2 Capture and Mitigation of Global Warming and Ocean Acidification
  10. Rolling Stones; Fast Weathering of Olivine in Shallow Seas for Cost-Effective CO2 Capture and Mitigation of Global Warming and Ocean Acidification