Not quite. There are quite a few different rock strata in Canada. I was talking about 4.1 by old gneiss which is granitic or continental in origin. But your greenstone belt is older than the gneiss that I linked so you did fin an older rock and it looks like it would be oceanic crust.<quoted text> The Canadian find is oceanic rock.
It is literally the basaltic and some has other properties, but is the first crust that formed as the Earth cooled and water condensed creating the shallow seas. And greenstone
The deformed volcanic sequences that form greenstone belts in the Canadian Shield contain hyaloclastite and pillow lavas, indicating these areas were once below sea level and the lava was rapidly cooled underwater. Pillow lavas more than two billion years old indicate large submarine volcanoes existed during the early stages of the Earth's formation.
The pillow lava pushed up the older oceanic crust in this case, the part we thought was gone forever from subduction.
The oldest rocks on Earth are 4.28 billion years old - the Nuvvuagittuq Greenstone Belt, exposed on the eastern shore of Hudson Bay, northern Quebec, Canada. With an age of about 4.28 billion years, it is the only portion of the Earth's crust known to have formed during the Hadean eon. In this greenstone belt the oldest dates came from rocks called "faux amphibolite," which are thought to be ancient volcanic deposits. These beat the previously oldest known rocks, which are about 4.03 billion years old and come from the Acasta Gneiss formation in Canada's Northwest Territories. The only older crustal material is from isolated mineral grains called zircons, which are highly resistant to weathering and geologic processes. The Nuvvuagittuq Greenstone Belt gives researchers a fresh perspective on the early separation of Earth's mantle from the crust. It is thought that a shallow ocean had already existed 300 million years after the Earth's formation. It raises puzzling questions as to ancient bacteria, as they are thought to be needed to precipitate iron availability for the formation of this type of rock. It might very well be that this rock may also contain traces of the oldest form of life in some way.
Interesting that they think life maybe found in it too.
Actually that makes more sense since the most common way to make continental crust is to take some older oceanic crust and partially remelt it. The lighter more easily melted minerals form granite and rhyolite the heavier remaining rock sinks into the mantle.