We know that the smartest geologist in the world was not there to observe how all those big rocks and cobbles got mixed in with the sediment? But let's see what Discovery Channel says about it?

The location of the glory hole  a name given to deposits at the base of ancient waterfalls...
Did you read the caption under the picture? A classic example of media indoctrination. It is completely wrong, and geologists know it. But is to lead the common man to believe everything happens s-l-o-w-l-y. The sediment rock mix was the result of waterfalls! Really? You mean like the waterfalls I used to swim under in North Carolina or currently hike through in Louisiana? I didn't see any cobbles or boulders coming over the falls. A flood? Oh yeah, a flood could bring those boulders...

...Do you sse mud slurries under falls or in moving current after a flood? You see rocks but sediments are washed away by the flood and the current after the flood. But you say "well, the cobbles were laid then the water slowed down and slowly covered them with mud." Okay, then what happens at the next flash flood? The sediment washes away. The water forms a current. If it reaches even medium regime speed, it washes loose sediments, and leaves rocks.
Here's an example...Scour from the interstitial spaces in cobble-bed riversV Jonker1* and A Rooseboom2
Abstract
The periodic removal of sand from the interstitial spaces between cobbles is extremely important for ecosystem functioning
in cobble-bed rivers. In order to flush fine sediments from the interstitial spaces between cobbles in river reaches downstream
of dams, specific dam releases known as flushing flows or sediment maintenance flows are utilised. This paper describes the
development and calibration of a mathematical model to predict the equilibrium depth of scour of fine sands from between
cobbles in terms of applied stream power principles. The model was developed with the aid of physical model experiments
and is founded on a stream power model which defines the condition of dynamic equilibrium in a deformed sand-bed river.
Calibration was done in the laboratory under clear water conditions and with uniform cobble sizes. The scouring of fine sands
in cobble-bed rivers is associated with an increase in absolute bed roughness and an associated decrease in the unit stream
power applied along the bed as the cobbles become exposed. When scour ceases, the sand particles on the bed are at the movement
threshold and critical conditions exist. In order to establish the relationship between equilibrium scour depth and bed
particle characteristics, the power which is required to suspend sand particles under laminar boundary conditions is equated ith the turbulent power being applied along the bed.
http://www.wrc.org.z...008_03_2068.pdf

Here's Bennington Vermont--Where's the mud?
Also, if all these rocks were from waterfalls, we would find evidence of deep erosion holes (like the falls I swimmed in), or a channel following the falls. As I said, I also go hiking in Louisiana. I go by several waterfalls. Do I see anything like the pictures above? NO. I see where the erosion has caused big soft "mud" boulders. But they are in a very limited area in SOME of the canyons, and they follow a narrow path. They aren't dispersed all over the place. But the rocks up in Alaska are mixed all through the sediment. I say this is a mud slurry that had enough force to carry all these rocks to one final depostion. The result of a huge and powerful catastrophe.
Geode "already knows" this stuff in Alaska is from catastrophe...or will he hold with DC--waterfalls? There seems to be a pardigm war in geology. Someone told DC the rocks are from "ancient waterfalls." But then you have papers like the following that acknowledge catastrophe.
Sedimentology, paleoflow dynamics and flood history of jokulhlaup deposits; paleohydrology of Holocene sediment sequences in southern Iceland sandur deposits
This paper examines the sedimentology of a series of deposits associated with catastrophic floods caused by subglacial volcanic eruptions in southern Iceland. A simple model is proposed for the interpretation of the sediments in terms of changes in flow characteristics of the fluid-sediment mix....These flood deposits alternate with, or are channeled into, more 'normal' sandur deposits, comprising heterogeneous, poorly sorted, clast-supported, imbricated, rounded cobble and pebble gravels (Type G). The dominant sediment sequences are interpreted as representing hyperconcentrated fluid-sediment mixtures, with dispersive stresses acting to create massive, poorly sorted, nongraded or inversely graded sediments, the latter characterized by large surface boulders.
I am often amazed at the language of these papers. They're using alot of jargon to tell us these "Holocene" floods caused a mud slurry. The same thing most thoughtful people with common sense can observe. By the way the Holocene is a more recent epoch, characterized by an ice age.