TL:DR Absolutely, not even an issue. There will undoubtedly be artifacts that are discernible from this alien civilization, after just a short period of time of only 60 million years. However, it depends on whether you want them to functionally survive, or just survive so that they are discernible.
In pure cosmological terms, 60 million years is just a drop in the bucket.
The oldest dated rocks formed on Earth, as an aggregate of minerals
that have not been subsequently broken down by erosion or melted, are
more than 4 billion years old, formed during the Hadean Eon of Earth's
geological history. Meteorites that were formed in other solar systems
can pre-date the Earth. Particles from the Murchison meteorite were
dated in January 2020 to be 7 billion years old.2
As another poster in another answer has stated, the fossil record on Earth goes back at least that far. See this, for instance.
Sixty-six million years ago, the asteroid that wiped out the dinosaurs
also ushered in the age of the mammals – an age that continues to this
Scientists have known little about the mammals that survived and
flourished in the years after the asteroid impact. Until now.
A study on a recent discovery of thousands of mammal fossils at a
nature preserve near Colorado Springs, Colorado, has shed light on the
So if archeologists on Earth can deduce what happened on Earth 60 million years ago, it is well within conjecture that remnants of a 60 million year old civilization could remain somewhere in the galaxy.
Based on the success of our archeologists today, here on Earth, we can say with some confidence:
If their function were purely decorative, they could still be discernible and their decorative nature appreciated.
If they were unmechanically functional (like a hammer, with no moving parts) their use would certainly still be discernible, and maybe even functional.
If they were mechanically functional (like a wheel and axle, a simple machine, or even gears and cogs) their function could be discernible, but they would probably not be functional.
If they depended on conducted energy, such as electricity, they would probably be a complete mess, undiscernible. Our electronics have a life much less than even 100 years, before the circuitry degenerates due to molecular and atomic drift. Passing electricity through a material causes all kinds of changes at the atomic level. However, advances in carbon nanotube technology suggests that with continued development, 'electronic' devices could be made from carbon nanotubes that might be discernible, but probably not functional, after that long. We simply do not know yet how stable we can make carbon nanotubes. After all, diamonds, that will last billions of years, are also made from carbon, in a matrix/lattice structure. If carbon nanotubes can be made even close to this stability, 60 million years is but a blink of the eye. It might depend on whether they are used, or dormant, for that length of time. Dormant devices may not degrade, as there is no conducted energy going through them. The problem with our electronics today, is that there is so much use of chemicals and substances that eventually dry out (insulation, heat transfer goo, and dielectrics in capacitors and transformers for instance). Our electronics will probably be discernible in a hundred years (if they are not recycled) but I doubt if they will be functional. Even electrical motors will be iffy after two hundred years of use.
Materials such as glass and diamonds will be around for billions of years. So if a diamond were engineered, for instance it was cut or engraved, it would be essentially intact. Decorative and functional objects and artifacts made from glass would also be intact and functional, after only such a short time.
A mathematical model shows it would take longer than the universe has
existed for room temperature cathedral glass to rearrange itself to
So yes, even after the demise of human civilization, after 60 million years there will still be evidence of our former existence from our artifacts that have survived. It will be much like archeologists sifting through the fossil record of Earth, going back some 60 million years ago, trying to decipher what we were all about, but our existence would certainly be evident.
However, functionality will be a completely different issue. But the question does not seem to require functionality, only discernibility.