BONNIFIELD AND KANTISHNA REGIONS. 225 
LIGNITE CREEK. 
In the valley of Lignite Creek, where the space between the hard- 
rock ridges is wider than in Healy Valley, these deposits extend from 
ithe schist ridge that limits the valley on the south to the base of 
Jumbo Dome, a distance of about 3 miles, and eastward till limited by 
Ithe schist ridge at the head of the creek. They have been cut to 
depths of 1,000 feet or more by the many tributaries of Lignite Creek, 
which have steep grades and form where crossing the resistant coal 
beds waterfalls up to about 30 feet in height. These narrow cuts are 
clogged with masses of material from the sandy beds that break 
away in great blocks from the steep bluff above to form sand heaps 
at the bottom, and contain blocks. of coal 20 feet or more in diameter. 
The following sections were observed. The first is at a point about 
6 miles above the mouth; the other section is about 3 miles farther 
upstream, near the headwaters and near the eastern limit of the 
occurrence. 
Section on Lignite Creek 6 miles above mouth. 
Overlying gravel. Feet. 
Thin beds coal alternating with sands and clays 250 
Coal * 18 
Sand 10 
Coal 1 
Clayey sand 10 
Sand, cross-bedded 100 
Coal 15 
Sands. 100 
Coal 8 
Sand 75 
Coal * 32 
[ Sandy clay 40 
1 Coal." 10 
! Sand 12 
Coal 20 
Sand, clay, and small amount of fine subangular quartz gravel 25 
Coal (only the top of a bed exposed). 
Total coal, 129 feet. 
Section near head of Lignite Creek. 
Overlying gravel. Feet. 
Coal (shaly) 8 
Sandy clays 50 
Coal 6 
Clay 10 
Coal 12 
Sands. 
Coal 1 
Gray sand and gravel, clayey toward top 40 
Coal 1J 
Friable clays - - 10 
Bull. 314—07 15 
