Yellowstone: Big Volcano Ready to Erupt | How the Earth Was Made (S1, E8) | Full Episode | History

This paragraph introduces Yellowstone National Park as one of the world's most geologically active places, located in Wyoming. It experiences up to 5,000 earthquakes annually and is home to more geysers and hot springs than the rest of the world combined. The narrator poses questions about the park's formation and its high level of activity, hinting at a violent past shaped by water, glaciers, and massive volcanic eruptions. The park's unique geology, stunning scenery, and wildlife attract millions of tourists each year. The paragraph sets the stage for a journey into the park's geological history and the mysteries beneath its surface.

This paragraph delves into the mechanics of Old Faithful, Yellowstone's most famous geyser, and how it serves as a key to understanding the geothermal activity beneath the park's surface. It explains the process of how rainwater seeps into the ground, gets heated by hot rocks, and creates pressure leading to an eruption. The paragraph also discusses the discovery of a solid boulder formed from sand grains cemented together by chemicals and pressure, which was ejected 3,000 years ago by a geyser explosion. Additionally, it describes the findings of a much larger geyser crater at Mary Bay in Yellowstone Lake, dating back 13,000 years, and the ongoing research into the gases emitted from underwater vents, which are similar to those found in volcanic eruptions.

This paragraph focuses on the evidence of volcanic activity beneath Yellowstone, including quartz crystals that suggest the presence of a volcano. It explains that the park's hot water features indicate the heat from a volcanic source is responsible for the geysers. The paragraph discusses the mystery of the volcano's location, given the park's gentle landscape, and the importance of monitoring the volcanic system due to its potential danger. It also touches on the history of scientific investigation into Yellowstone, from Native American legends to early explorers and modern geologists, who eventually discovered the park is situated within a massive volcanic crater.

This paragraph discusses the presence of rhyolite lava in Yellowstone, which is associated with extremely violent volcanic eruptions. The Lodge Pole Pines, which thrive on poor soil derived from rhyolite, and the abundance of mosquitoes, which breed in stagnant waters created by the non-permeable rhyolite, both serve as indicators of the lava's presence. The paragraph explains that rhyolite lava is much thicker and more viscous than other types, leading to explosive eruptions when gas is trapped within it.

This paragraph reveals the mystery of Yellowstone's super eruptions, which were so massive they blew the volcano to pieces. Evidence such as the swarms of mosquitoes indicating rhyolite lava, obsidian glass 60 miles away showing the spread of ash flows, and thick layers of debris confirming the size of the explosion, all point to a colossal volcanic event. The paragraph describes how the super eruption helped solve the mystery of the missing volcano and how the park is located inside one of the largest volcanic craters on Earth. It also discusses the discovery of the park's position within the crater and the realization that a deadly danger still lurks beneath the ground.

This paragraph explains the aftermath of the super eruption, detailing how the landscape was buried by subsequent lava flows and ice, shaping Yellowstone's current appearance. It describes how the initial explosive lava was followed by less explosive, runnier lava that smoothed the volcanic landscape. The paragraph also discusses the discovery of the earthquake patterns and the realization that they are signs of an underground magma chamber, which still exists beneath the park and is responsible for the fault lines and earthquakes. Additionally, it highlights the discovery of another, even larger structure under the park, which is a colossal volcanic pipe or hotspot that extends hundreds of miles into the Earth.

This paragraph explores the role of plate tectonics in the formation of the Yellowstone hotspot and the chain of ancient volcanic craters found on the Snake River Plain. It explains how the American continent's movement over the stationary hotspot created a series of super eruptions, with each crater being progressively older as one moves away from Yellowstone. The paragraph clarifies the misconception that the hotspot is moving, instead revealing that it is the North American plate that is shifting, continually pushing new land over the hotspot and forming the Snake River Plain. The pattern of earthquakes around Yellowstone also supports this theory, as they trace out a giant V shape on the Earth's surface, indicative of the plate's movement and the hotspot's stationary nature.

This paragraph discusses the current signs of geological unrest in Yellowstone, indicating that the super volcano may be active. It highlights the increase in the frequency of small earthquakes, the rising of the park's land due to the expansion of the magma chamber, and the resurfacing of a sunken boat from Yellowstone Lake as evidence of the land's uplift. The paragraph emphasizes that while the park's geological forces are revealing the presence of a slumbering monster beneath, the exact timing of a potential future eruption remains unknown. However, the frequency of past eruptions suggests that another super eruption could be imminent on a geological timescale.

The final paragraph addresses the critical question of when Yellowstone's super volcano will erupt again. It acknowledges the evidence of increasing geological activity, such as the rise in the number of earthquakes and the uplift of the land, as potential warning signs of an impending eruption. The paragraph reflects on the historical pattern of super eruptions and the potential catastrophic consequences if such an event were to occur again. It concludes with a sobering reminder that while the possibility of future eruptions is certain, the timing remains unpredictable, leaving the question of the next super eruption's timing open and the potential threat very real.