The 2021 Crash Town earthquake registered 5.5 on the moment magnitude scale and struck near Crash Town on December 4, 2021, at 06:36:18 Telamon Sea Time at a depth of 0.127 mi (730 studs). It was the largest earthquake ever recorded in the state in which Crash Town is located, easily surpassing an 1879 earthquake, and both the most powerful and most devastating in the region since 1811-12. It was a strike-slip shock, producing catastrophic damage across much of the southwestern region of the state and into southeast regions of bordering states. Significant shaking and widespread mild damage were reported. Despite shaking in the area, it led to no "sense of panic", despite damage in the area.
| UTC time | 14:36:18 |
|---|---|
| Roblox Seismological Centre event | Unknown |
| Local date | December 4, 2021 |
| Local time | 06:36:18 |
| Depth | 0.127 miles |
| Epicenter | Crash Town |
| Fault | Unknown |
| Areas affected | Crash Town |
| Tsunami | False |
| Casualties | Unknown confirmed dead, Unknown injured |
| Required Information | |
| Downdip rupture width in miles | 3.889 |
| Rupture area in square miles | 12.18 |
| Surface rupture length in miles | 2.377 |
| Subsurface rupture length in miles | 3.75 |
| Average displacement in feet | 0.327 |
| Fault slip rate in inches per year | 0.001703 |
| Chikorita Magnitude | 5.5 Mchikorita (Moderate) |
The earthquake's damage worsened impacts from a tornado outbreak that had struck much of the same areas on the same day, and the impacts from said earthquake were exacerbated by the relative lack of preparedness for an earthquake of such an intensity, including lack of building codes to allow buildings to withstand prolonged shaking at such a level. The state government was criticized for its lack of forethought into such a scenario unfolding, especially given days of warning from seismologists of the increasing risk of a significant earthquake in the region. The region's infrastructure was also not built to withstand such a strong earthquake occurring, and over 0.3 miles (1.72 kilo-studs) of Interblox highway in the southwestern region of the state was closed in the immediate aftermath of the earthquake due to safety concerns.
Earthquake
When the earthquake struck at 06:36 on December 4, 2021, and ended 18 seconds later, it was initially reported by the Robloxian Geological Survey to have a magnitude of 5.7 M, which would have made it 31 times weaker than the 1992 Great Bloxington Island Earthquake. It was later upgraded to 5.8 M before being downgraded to 5.5 M on the same day. The earthquake occurred in a seismic zone adjacent to another seismic zone, which had been monitored by seismologists for the potential of increased earthquake activity for tens of days prior to the 2021 earthquake. This seismic zone was also responsible for causing two earthquakes that struck five months ago and three months ago, respectively.
Areas Felt
The earthquake was felt across a wide area. This earthquake was quite similar to an earthquake five months ago in the way that it could be felt across much wider areas compared to typical earthquakes in other regions, as the presence of bedrock under many areas in the region allows seismic waves to propagate further.
Aftershocks
There were four aftershocks recorded, all epicentered at or near Crash Town. The first, being a 4.6 M earthquake, struck just 18 seconds after the mainshock ended, significantly worsening damage. The other stand-out shocks included a M2.9 on 08:31:30, M3.1 on 09:43:30, and a M1.9 (only detected by seismological instruments) on 13:19:30.