Calling this muddle a first draft seems inaccurate; the first draft is the thing I get after I rewrite the starting draft, really. Plus I rewrite so much--and in such a nonlinear way--that I eventually lose track of how many drafts I've been through anyway. Rough draft is better. I'm also fond of the term zeroth draft, which I hear used more and more often.
But I've been thinking lately that exploratory draft would be better still. I'm sending out my advance party; I'm checking out the terrain. I'm learning the landscape and weather; I'm seeing who lives in this place and what they do when I poke at them. It often (usually? but every book is different) takes me a whole draft to even begin to learn these things. Along the way I'll mutter that it shouldn't take me so long, but it does.
Then--once the advance party has brought back its report--then I can get down to the business of figuring out how to tell a real story in this new place I've discovered.