This image shows a model of the rock cycle. At point R, rocks melt underground to form magma.
Which is another process that contributes to the
formation of rock at point R?
Point R
compacting of sediments on the mountain
cooling as the lava runs down the mountain
weathering of the mountain from the environment
eroding of different rocks at the base of the
mountain

Why is the huronian supergroup rock formation particularly interesting to scientists? because it looks like a cross-section of a giant, stone encyclopedia because it formed during the period when oxygen began to accumulate in the atmosphere because it contains unusually large amounts of oxygen and sulfur because it dramatically altered the planet's development when it first formed