There's an SF story I don't want to spoiler that includes a metal shipwreck getting buried in sediment and making it into sedimentary rock. Google suggests that over 20k ships were lost in WWII alone.
Even reduced to little more than rust and concretions, that will make for some bloody funny fossils in the future. Cars might only last 15 years, but scrapyards last a hell of a lot longer than that.
So for there to be no possibility of artifact survival, I think you need complete turnover of the rocks in the Earth's crust. The oldest rocks on Earth are found in the Acasta Gneiss in Canada, and are 3.58 to 4.031 billion years old.
For ruling out a prehuman civilization, the question of the maximum theoretical "resolution" that we can observe the Earth at might be more important than the survival of the artifacts. I reckon something always survives; the real question is can we find it? For example finding Ötzi was dumb luck... how many Ötzi's have we missed? How many peat bog bodies ended up as John Innes No3?
There was a study funded by NASA on the topic which made the rounds back in the day. Here is the Scientific American take: [1], here is PBS Space Time YouTube: [2]
The topic pops up now and again, most recently called the The Silurian Hypothesis. There are many articles in respectable sources on the subject, it goes beyond science fiction into literal science.
For example, you might wonder how long it would take for some large portion of the surface of the earth to subduct. I believe the answer to that question is in the paper discussed in that article.
No problem. From what I remember (thirty years ago!) at that stage in his career he was trying to stake out as many successful futurist predictions as possible, so the novels from around that time feel like excuses to shoehorn in lots of near-future "...and then there was a peaceful revolution in South Africa" stabs in the dark. Honestly, I found it tiresome. YMMV.
Even reduced to little more than rust and concretions, that will make for some bloody funny fossils in the future. Cars might only last 15 years, but scrapyards last a hell of a lot longer than that.
So for there to be no possibility of artifact survival, I think you need complete turnover of the rocks in the Earth's crust. The oldest rocks on Earth are found in the Acasta Gneiss in Canada, and are 3.58 to 4.031 billion years old.
For ruling out a prehuman civilization, the question of the maximum theoretical "resolution" that we can observe the Earth at might be more important than the survival of the artifacts. I reckon something always survives; the real question is can we find it? For example finding Ötzi was dumb luck... how many Ötzi's have we missed? How many peat bog bodies ended up as John Innes No3?