2021 Terro Valley Earthquake

The 2021 Terro Valley Earthquake was a 9.2 moment magnitude earthquake that struck in the Terro Valley on June 24, 2021. The earthquake caused Terro Valley's walls to collapse, causing debris to level Pine County towns except for Kyle City, which is the county seat of Pine County, and Mount Charcoal, which started its first eruption phase two days after this earthquake.

Pre-earthquake
Until 7 months prior to the earthquake, the area was quiet. 5 months prior to the earthquake, a tremor, a magnitude 4.2, impacted around 9 miles south of the main earthquake's epicenter. Much speculation went into this tremor as it was thought to have been a foreshock of an earthquake. This was the case. 12 days later, another, slightly larger, tremor impacted the same area, with a magnitude of 5.3. Even more speculation went into this, as foreshocks, on average, increased in size and seismologists prayed this will be the main earthquake.

Pine County issued an extra precaution warning for Terro Valley. Tremors ranging between 4.5 and 5.5 struck in the same area 24 days before the main earthquake. The Roblox Geological Survey ( RGS ) put the area surrounding Terro Valley in "High" risk of a major earthquake for 5 months. 18 days before the earthquake, a non-significant magnitude 5.3 earthquake struck Storm Valley, injuring 1. 12 days before the earthquake, a 6.3 magnitude earthquake impacted. 6 days before the earthquake, the area was quiet for the third time until 2 days before the earthquake, when a magnitude 7.2 earthquake impacted.

During earthquake
At June 24, 2021, the 9.2 magnitude earthquake struck violently. Shaking was strong enough that the walls of Terro Valley collapsed, causing debris to level Pine County towns except for Kyle City, which is the county seat of Pine County, and Mount Charcoal.

Post-earthquake
This tremor was followed by almost 44,000 aftershocks, with the second strongest, a 7.9 magnitude tremor occurring 5 hours after the main shock. 28% were over magnitude 5, 48% were over magnitude 4, and the rest below 4. This earthquake, due to the extensive nature of it, also caused other, more local earthquakes, such as a 5.5 on Site-14, a 5.7 in Pine County, and a 5.0 west of Pine County. Medium-sized fires broke out near Pine County and fire fighters were about to put out the massive fires when the first strongest, a 8.3 magnitude tremor occurred. Most of the aftershocks over magnitude 4.3 were between 6.8 to 8.8.

Eruption
2021 Mount Charcoal Eruption