You're going about this wrong. When you write a piece of fiction (such as an SCP document), you're trying to elicit an emotional reaction. If your first thought on how to write for a site like this is, "how can i make it about a vibraphone," then you're not going to get anywhere. What you want to do is, try to come up with a sequence of events in your head, a narrative. Then decide how you'll want the audience to feel once they've read this sequence of events. Then you'll try to create an image that presents that narrative in a context that evokes that emotion.
I'll give you an example that I wrote. Imagine trying to elicit a combination of shock, laughter, and revulsion in your target audience (in this case, the SCP wiki). What's something potentially repulsive, shocking, and humorous? Well, my answer was several hundred Nazis falling to their deaths in a way that'd evoke both humor at their plight and horror at the plight of the poor sods on the ground below them. How do we get there? Well, why not a time machine that's been sabotaged? From there it was a matter of hammering out the more fine details.
Don't focus on the anomaly. Don't focus on the image. Focus on the emotion and work from there.