I can show you "bone" (fossils aren't bones - the tissues and cells have been replaced with minerals) that has lasted dozens of millions of years. Can you show me one thing from our current civilization that will definitely last that long? The pyramids of Giza have lasted about 5000 years, but will be ground to dust over millions of years. Their location isn't going to remain desert indefinitely, and the preservation effects of desert will be quickly undone by different kinds of weather. The roads we built will be buried under sediment and compressed to a thin black line in the stratigraphic record. Our worked metal structures will rust and decay to nothing. We've built nothing that can withstand truly deep time.
Sorry to burst your bubble.
In 50 million years, some alien is going to investigate it and know something involving happened there.