Michael Poland

Michael Poland

Silver Gate was Mammoth before Mammoth Hot Springs

By: - September 8, 2021

Just south of Mammoth Hot Springs, near the north entrance of Yellowstone National Park, lies a jumble of white/gray rock known as the Hoodoos or, more formally, Silver Gate.  The origin of this deposit is a quintessential tale of the dynamic nature of Yellowstone. Imagine you have just arrived at the north entrance to Yellowstone […]

Meet Yellowstone National Park’s sibling, Taupō, New Zealand

By: - July 19, 2021

Yellowstone is not the only large caldera system in the world.  Caldera systems can be found all over the planet. In New Zealand, the Taupō caldera system shares many similarities with Yellowstone—a history of large eruptions, geysers and hot springs, and even earthquake swarms and ground deformation, some of which might be related to magmatic intrusions. […]

Where did that 60 million years go?

By: - June 14, 2021

Visitors to Mammoth Hot Springs in Yellowstone National Park might have noticed an odd geological feature near the top of Mount Everts—an unconformity! This juxtaposition of different rocks serves as a marker of missing history in the Yellowstone region. An unconformity at the top of Mount Everts is located where the Huckleberry Ridge Tuff, 2.1 million […]

The odd columns of Sheepeater Cliffs

By: - April 26, 2021

Visitors to Yellowstone might have noticed a small sign between Mammoth Hot Springs and Norris Junction that points down a side road to “Sheepeater Cliff.”  A short drive down this road reveals an exceptional example of a common feature of volcanic flows, columnar jointing. Sheepeater Cliffs is part of a basaltic lava flow that erupted north and […]