Lol. Here I am worried I came off as too defensive, but now that I've slept on it, I feel it was reasonable. They strike me as the person that thinks they are an expert on every subject because they read an article after taking some photos. Probably cans his farts to smell them later.

>I think you are remembering that part of geology class somewhat incompletely. That's fine, geology is a huge subject.

I was just making a quick response as noted in my original comment. Hours before you replied I even said it was explained in more depth by comments further down. I was at work, I didn't have time to go into detail.

As far as remembering that part of geology class incompletely, which class are you talking about? Stratification and Sedimentation, Hydrogeology, structural geology, Geophysics, Sedimentology...? Because as I said in my original comment, I have a degree in geology.

Was your entire objective to post your photos, toot your own horn, and act smugly smarter than someone with a degree in the topic at hand? Because it's not a good look.

Jagged coastlines near the poles are caused by glaciation cutting through the landmass and isostatic rebound.

Smooth coastlines in the tropics and as you near the equator are due to heavier weathering from rain and liquid water.

Ice cuts, water erodes.

This is just the simple explanation from what I remember. Credentials- B Sc. Geology.

Edit: Additionally, I'd also like to point out that there are exceptions to this. Abundance of "jagged" toward the poles and "smooth" near the equator is just describing prevalence. Citing a smooth coast near a pole or a jagged pole near the equator doesn't discredit prevalence. For example, Hawaii, being relatively recently created by magma plumes it will take lots of time due to the mineral composition and youth of the islands for them to either smooth out or erode away. Another example is the tectonic uplift along the US west coast.

Edit 2: There are some top level comments that are more descriptive than mine with some good additional information. Don't just read mine because its higher and forget to scroll down for the more in depth comments.