Overflows of the Cache River in this broad, lowland area were probably more frequent before drainage accelerated channel erosion, evidenced by downcutting
, and lowering of the level of the river.
The exposed glaciomarine sediments show relict deformation structures likely related to fluvial downcutting
of exposed sediments shortly after a drop in sea-level that exposed the sediments.
by upper Mud Brook is limited by a sandstone knickpoint near the intersection of State Route 8 and Graham Road in the southwestern part of the study area (Fig.
and erosion of the rift flanks - first by rivers and then, about 34 million years ago, by the first glaciers of the East Antarctic Ice Sheet - further unloaded the crust, which buoyed the range higher, the authors suggested.
Urbanization lowers base flow, and creates downcutting
due to lack of space to meander (Bernhardt and Palme, 2007).
Although timing of this event is poorly constrained, the initial spillover most likely occurred between 2 and 4 Ma with subsequent slow downcutting
of the divide (Wood and Clemens, 2002).
on creek walls was also observed.
of fine-grained lake bed substrates may accelerate formation of deeper water offshore and result in increased wave energy to the near shore.
In this case the process included: 1) deep incision of a valley meander into bedrock, 2) partial alluvial backfilling of that valley, mostly by outwash of one of the pre-Wisconsinan glaciers, 3) opportunistic relocation of the channel across the bedrock neck of the meander at a low spot, and 4) downcutting
of the new channel as base level was lowered (Bajza 1944).
The northward advance of the Pennsylvanian sea across the area caused the streams that had been actively downcutting
to begin aggrading and filling their valleys with the Caseyville alluvial sediments.
Its geomorphological history over the last 20,000 years has been reconstructed from studies of repeated sequences (or cyclothems) of deposits in the delta, in lower and mid valley, and swamps of the Sudan which suggest a series of downcutting
, aggradation and channel avulsion events.
He concluded that the suburban development caused expansion of the stream floodplains and subsequent downcutting
of the stream channels.