This thing is really quite huge, and from the mound looks like it must have once been a geyser or at least flowed over the side. I read somewhere on the web (so it must be true) that an early European settler reported that the water level fluctuated a lot. The same person also reported flames erupting from it on occasion, so that may or may not be an entirely reliable source. I'll add a picture with human for scale soon.
Since I don't have a wider lens for my dSLR, I used my analog SLR (film camera) with a 24mm lens for all my wide shots on this trip. I worked on this slide for a while, processing it various ways to try and bring out the full dynamic range. The rock is nearly white and in full mid-day sunlight, and the water at the bottom is quite dark. I originally posted the best I had after an evening of work, 4 different exposure scans of the slide fed into enfuse with some PS post processing. But a slight red color cast in the shortest exposure (which had all the rock detail) was really throwing everything off. So I've replaced this with a second try, I added a 5th even longer exposure slide scan to the mix so that you can see more of the pool, and set VueScan to "landscape" color mode which took out the color cast in the shortest exposure.