About Nuvvuagittuq Greenstone Belt
- The Nuvvuagittuq Greenstone Belt is a region of ancient rock formations located on the eastern shore of Hudson Bay in Quebec, Canada.
- These rocks have been known for their exceptional age and unique geological features, making the region a critical site for studies of Earth’s early history.
- This makes them potentially the oldest known rocks on Earth, challenging earlier estimates and rivalling other ancient formations like the Acasta Gneiss Complex (∼4 billion years old).
Scientific Significance
- Researchers use radiometric dating, which tracks the decay of radioactive isotopes over time.
- Earth formed around 5 billion years ago, but most early rocks were destroyed or transformed due to tectonic activity and melting.
- Rocks older than 4 billion years are extremely rare and provide a window into the planet's earliest crust.
- The rock site lies on Inuit tribal land in Inukjuak, Nunavik.
- Due to environmental damage from earlier research and reports of rock samples being sold online, the local Inuit community has restricted further sampling.
- The community, led by the Pituvik Landholding Corporation, seeks to collaborate with scientists to create a provincial park to balance research and conservation.
What are Ultramafic Rocks?
- Ultramafic rocks are dark-colored igneous or meta-igneous rocks rich in Magnesium Oxide (MgO) and Iron Oxide (FeO), but low in Silica.
- They contain over 90% mafic minerals, and are poor in potassium.
- The Earth’s mantle is believed to be composed predominantly of ultramafic rock types.
- These rocks are commonly found in orogenic (mountain-forming) belts and can offer insights into mantle composition and deep Earth processes.
