PLACERS OF THE RAMPART REGION. 71 
cut creeks cutting the bench and have rolled down into the present 
stream beds where the great number of large quartzite bowlders make 
considerable trouble for the miner. 
The origin of these gravels has been puzzling to the miners and 
prospectors. Their great width and depth, their position so far 
above the present gravels of Minook Creek, and the presence of the 
great quantity of heavy quartzite bowlders, where the bed rock would 
afford no such material, have made it seem to many miners necessary 
to assume that some larger stream, possibly the Yukon itself, once 
flowed across the country. This view received some support from the 
apparent course of an old channel either toward or from the north- 
east, while the present stream flows somewhat west of north from the 
mouth of Hunter Creek. 
The data at hand suggest that Minook Creek while flowing toward 
the Yukon to the northeast of its present course, wdien the land stood 
at a lower altitude, had formed a flood plain of approximately the 
dimensions of the present high bench. With the elevation of the land 
along the Yukon, the effects of which are to be seen over hundreds 
of miles, the mouth of Minook Creek may have been raised through 
local variations, its grade may have been lessened, and the former 
flood plain may have had the gravels under discussion deposited over 
it. As the elevation went on, the creek was forced to the west and 
finally found a new outlet to the Yukon. The elevation continued, 
and Minook Creek cut downward, leaving its gravels on a bench 
above it. The elevation did not, perhaps, proceed steadily but peri- 
odically, and thus intermediate benches were formed. 
The smaller creeks, Hunter, Little Minook, and Hoosier, all give 
some support to this hypothesis. By reference to the map (PL II, 
p. GO) it will be noticed that each of them, upon reaching the 
edge of the bench gravels, sharply changes its course and flows west- 
ward through the high bench. In the case of Hunter Creek and 
Little Minook Creek the change in direction amounts to about a 
right angle, while with Hoosier Creek the angle is less acute but still 
noticeable. The eastern limit of the bench gravels probably marks 
the mouths of the various streams when this line represented the 
course of Minook Creek. As the course of Minook Creek w T as shifted 
to the w r est the tributary creeks followed under the influence of the 
same force that shifted the larger stream. The age of the bench is 
probably Pleistocene, as is shown by vertebrate fossils found in the 
gravels of Little Minook Junior Creek, which seem to be the oldest 
gravels of the streams cutting the bench. 
Gold has been found in the bench at many places, and betw T een 
Little Minook Creek and Hunter Creek a large amount of prospecting 
has been done. This portion of the bench is known as " Idaho Bar." 
