1. Spreading finely ground basalt rock on farmlands extensively
2. Increasing the alkalinity of oceans by adding lime
3. Capturing carbon dioxide released by various industries and pumping it into abandoned subterranean mines in the form of carbonated waters

How many of the above activities are often considered and discussed for carbon capture and sequestration?

a. Only one
b. Only two
c. All three
d. None

Question from UPSC Prelims 2023 GS Paper

Explanation :

Correct Answer -> c. All three

Carbon capture and sequestration

1. Spreading finely ground basalt rock on farmlands extensively: This process, known as enhanced weathering, involves spreading crushed rocks that are rich in minerals like basalt on farmlands. The minerals in the rocks react with carbon dioxide in the air and form stable compounds, thereby capturing and storing the carbon dioxide.
See this -> Enhanced Weathering: crushed rocks spread on farmland can capture billions of tons of CO2/year – Energy Post

2. Increasing the alkalinity of oceans by adding lime: This method involves adding alkaline materials, such as lime, to the ocean to increase its capacity to absorb and store carbon dioxide. This process can help counteract ocean acidification and promote the formation of stable carbonate minerals, which can store carbon dioxide for long periods.

3. Capturing carbon dioxide released by various industries and pumping it into abandoned subterranean mines in the form of carbonated waters: This process, known as carbon capture and storage (CCS), involves capturing carbon dioxide emissions from industrial sources, such as power plants, and injecting the captured gas into underground geological formations, such as abandoned mines or saline aquifers, for long-term storage.