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15

The effects of Earth's past climate variations on the landscape, especially glaciation, cannot be underestimated. The multiple glacial advances and retreats over the last 4 million years or so have been a major (and sometimes the principal) force that shaped the current landscape. We're actually living in one of the temporary glacial minima - there will be ...


7

The transformation of sand into sandstone per se cannot be directly witnessed, as it's happening deep in the earth. However, there are types of cementation that happen quickly and in plain view: A ScienceDirect article on Cementation says: Cementation is the precipitation of a binding material around grains, thereby filling the pores of a sediment. Berner (...


4

By far most naturally occurring hydrates are methane hydrates. However, Dillon[1] documents hydration of other gases including carbon dioxide in some places such as the Gulf of Mexico: Many gas hydrates are stable in the deep ocean conditions, but methane hydrate is by far the dominant type, making up >99% of gas hydrate in the ocean floor. The methane ...


4

As I understand it, the current explanation for these deposits' existence is the carboniferous period when plants basically evolved woody structures that allowed them to grow trunks and grow tall. This is a minor point, but you're writing about coal rather than petroleum. Most geologists think petroleum is also of biogenic origin, but resulted from sea-...


4

You could mention the fact that the solid Earth (i.e., not the atmosphere) is slowly cooling down, as the two main sources of heat, primordial and radioactive, are slowly decaying. Because of this, the planet may become tectonically dead at some point. Gradual change over long periods of time is known as uniformitarianism, and has been opposed to ...


2

What you are asking about is the formation of sandstone. There is more to the process than just applying pressure; chemical changes, pressure, water and heat are all involved in the process. When sand deposits accumulate they undergo a process called diagenesis, which involves, physical and chemical changes in sediments first caused by water-rock ...


1

Carbon cycling through the mantle is a hugely important geologic process. Carbon gets into the mantle when subducted continental arc materials bearing rich, organic runoff are carried to depth, then exuded through volcanism at plate boundaries. That rich organic runoff is created by rain which is deeply influenced by... Oceanic currents which largely ...


1

Major geologic changes occur during natural events. Events like wildfire, floods, earthquakes, drought, volcanic eruptions, tsunamis, etc. can severely alter the landscape and allow new geologic processes to take place. For instance, after a landscape is hit by wildfire, it is easily subject to flash flooding and you get soil loss. This was not really &...


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