Got this just now (during the event, naturally) - mining minigame graphics behave like the Romulan radiation scan - i.e. the triangle graphic just floats down the screen to disappear and reappear from the top, but won't rotate or resize. I'd been doing radiation scans (and picked up the new daily) on New Romulus just prior, so don't know if it was "stuck" somehow on that system.
Logging out and back in doesn't clear it, but a complete restart of the game does. However, I'd wasted multiple mining attempts by then (having dropped the rollover daily and re-picked the mission to see if that cured it).