story identification - Trying to recall a sci-fi book I read in the '70s

When I was a teen, in the '70s, I recall reading a sci-fi book about an arctic discovery. I seem to recall that explorers had found the remnants of an ancient civilization, and I think had found one of the ancient people frozen. I think there may have been a sort of pyramid on the cover of the book. Also I recall that the ancient civilization had advanced technology, and there was a gloved weapon that I seem to remember you fired by raising one of your fingers. I have become nostalgic and would love to reread this and other books I read during my youth.

Thanks.