The Lance/Hell Creek As a Flood Deposit

Okay, new term.You said:"Splay deposits (which occur when channel waters break the levee at the edge of the channel and deposit (usually sand) out over the floodplain) tend to be localized."So that would be like these deposits?And later you said:"you'll notice that the flood plain of the active channel is a mess of abandoned channels and oxbows."which would be something like what is shown in this image and this image where each of the swirls is some earlier fossil riverbed?

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Immigration has been a problem Since 1607!

Okday, well the really cool meandering river image that I was wondering if it had been named for a star cluster.

Yeah, sorry...it's hard not to keep doing that... Yes! Exactly. Indeed, I've used that image before. Yes! Exactly. Those are good examples.

Okay, so I think I have it. When we take a slice through the area we see mostly mud but then places where there is sand. The sand spots are either old riverbeds or deposits from bank overflow and in those cases we see sand where the water was moving faster and mud or silt where it was moving slower or sitting steady.BUT ...the important point is it is not one event but rather a whole series of events that have left us evidence at different levels.Is that correct?

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Immigration has been a problem Since 1607!

Yeah.
I'm gonna email you some more photos.

Yes...precisely. And this is critical...any given outcrop (surface exposure of bedrock, bedrock being the material that underlies the current soil profiles in an area) of meandering river deposits has a time component to it...and you can almost think of it as three time components. t1 would be deposits that are contemporaneous with the active channel (e.g., a crevasse splay sand deposit formed during a flood event on that channel), t0 would be those deposits formed by earlier channels (geologically older) and t2 would be those deposits formed by later channels (geologically younger). Any given outcrop can display features formed at t0, t1, or2, or a combination of the three--so it isn't like we can usually trace a sand or mud from single active channel very far across the landscape, EVEN IF we find a continuous bed.