It’s open to interpretation.
There are some good arguments that it is supposed to not describe a literal physical event, ie in the The Resurrection of Jesus: A New Historiographical Approach by Mike Licona (or so I hear, I personally haven’t read it).
However, what is interesting is that geological investigation shows that it is very likely there was an earthquake around the time of 30s AD, and there is a possible excerpt to the ‘darkness’ described in the text.
However, there is a mistake in thinking that because it seems important to us, there’d be others writing about it. That’s not how it works. First, there’s thousands of years of difference and works may be lost. Second, it was in a different society wherein most were not literate. Many events were not written down until much later, or at least until when those who were witnesses began to die off.
For isntance, a MAJOR volcanic eruption, Mt Vesuvius, caused major losses in Roman officials and much disaster.
You know how many writings we have about it? One. And that is in passing reference in a letter.
