On 5 October 2024, a 4.5-magnitude seismic event occurred in Iran’s Semnan province, sparking speculation that Iran has tested a nuclear weapon for the first time.
Such a seismic event is typically the result of an earthquake, but speculation has arisen on social media suggesting the event was instead an underground nuclear test carried out by the Islamic Republic in response to Israeli threats to bomb Tehran’s nuclear energy and oil facilities.
According to Iranian sources speaking with The Cradle, the possibility that a nuclear test was indeed conducted is being discussed at high levels in Iran.
The speculation that Iran carried out a nuclear test comes just days after the Heritage Foundation, a right-wing think tank in the US, published a report stating that “Iran can produce nuclear weapons far more rapidly than expected.”
Published on 1 October, the report noted that in late April 2024, a senior Iranian lawmaker stated that there is only a “one-week gap from the issuance of the order to the first test” of a nuclear bomb.
From the comments, it seems likely this was not a nuclear test.
https://www.usgs.gov/faqs/why-do-so-many-earthquakes-occur-a-depth-10km
Don't know if it was a nuke or not, but the 10km bit isn't info one way or another.
TIL, thank you!