Day 4 Oct 13, 2021 Wednesday:

We entered the park thru the west entrance as usual,

Again, the Madison river had another facet. There was no river breath this time, but the banks were all piled with snow, and the river appeared calm and mirror like.

MAMMOTH HOT SPRINGS

We went to see Mammoth hot springs, but noticed cars were stopped ahead of us. The ranger came by and told us that the roads up ahead were very icy & slippery, and that only all-wheel drive vehicles were been allow to pass at that time. He said that the park trucks were in the process of dumping sand / gravel on the roads to increase traction, and that we could wait around for a few minutes till they were done, before being allowed to proceed.

After a few minutes of waiting, the Ranger escorted us in his park vehicle and we reached Mammoth.

We saw the Travertine terraces.

Minerals along with heat, a natural “plumbing” system, water, and limestone contribute to the beautiful terrace structures, Small earthquakes may keep the plumbing open.

Limestone, deposited here millions of years ago when a vast sea covered this area, provides the final ingredient. Hot water with dissolved carbon dioxide makes a solution of weak carbonic acid. As the solution rises through rock, it dissolves calcium carbonate, the primary compound in limestone. At the surface, the calcium carbonate is deposited in the form of travertine, the rock that forms the terraces of Mammoth Hot Springs.