What is the relationship between YEC and rapture theology?

I'm curious about the relationship between those who adhere to young-earth creationism, and those who adhere to Rapture theology (as expressed in the *Left Behind* series, for example, and similar related belief systems most commonly associated with fundamentalism and dispensationalism). Are these, generally, the same people? Or is there a large divergence between these two groups? I know a good many Christians who believe in both. I know a few who reject both. I don't know specifically of anyone who accepts one view, but rejects the other, although they may exist and I just don't know because the discussion topic hasn't come up. And at least superficially, they both appear to have their roots in fundamentalism. But I wonder how substantial this similarity is. To be a bit more specific, 1. Are there any theological foundations on which both views are built? Or does one view depend in any way on the other? (Does Rapture theology depend on an literal Adam, for instance.) 2. What is the cultural relationship between the two theologies? If we were to, for example, draw a Venn diagram of these two theologies, what would it look like? Have any polls or studies been done on this topic?