CENTRALIA COAL
FIRE
Rt. 61 in eastern
Pennsylvania runs through some hilly coal country. In the Western Middle
Anthracite Field, east of Shamokin and Mount Carmel, the road goes through the
ghost town of Centralia - one of the stranger sights in eastern America.
Just south of Centralia, Rt. 61 takes a sharp turn at a mound of debris (see
below). The modern road bypasses what used to be a newly paved road out
of Centralia. Kinda strange.
At the other end of the
blocked stretch of road, the following sign has been posted by the Pennsylvania
highway department. Really kinda strange!
One can walk along the
abandoned stretch of road. The asphalt is buckled, bowed, cracked,
fissured, and smoking. Centralia, Pennsylvania is a famous place for
observing the effects of an underground coal fire. The fire
started in late May 1962. Several stories are around that purport to
explain the start of the fire. The most plausible is that the fire was
accidentally set by firemen hired by town officials - they were burning garbage
in the town dump to increase space (or to diminish foul odors), in preparation
for an upcoming holiday (Memorial Day). An exposed coal bed was ignited,
and it's been burning ever since. It'll burn forever (as long as the coal
seam exists).
Centralia Underground Coal
Fire
- subsidence has destroyed former Rt. 61. The photo above & below are
what the road looked like in fall 2000 (Kent State University geology majors
for scale).
Centralia Underground Coal
Fire
- this is what the same stretch of road looked like in summer 2006 (above &
below). The main fissure down the center of the road has noticeably
widened (Ohio State University at Newark geologist & biologist for
scale). Looking ~SW.
A major, expensive operation
was undertaken to extinguish the coal fire. A huge trench was dug just
south of town. Officials hoped to intercept & dig out the offending
coal seam before the fire spread too far. The interception trench project
failed to put out the fire.
Centralia Interception
Trench
as it looked in fall 2000. Looking WSW.
Centralia Interception
Trench
as it looked in summer 2006. Looking NE.
The coal bed that's on fire
is the Buck Mountain Coal (aka No. 5 Coal), at the base of the Llewellyn
Formation. The bed defines the stratigraphic contact between the
Llewellyn Fm. and the underlying Pottsville Formation. Anthracite and
sub-anthracite coal beds of the Llewellyn Formation have tremendous economic
significance in eastern Pennsylvania. The most important coal interval in
the Llewellyn is the Mammoth Coal Zone (aka No. 8 Coal, No. 8˝ Coal, and
No. 9 Coal).
Age of Buck Mountain Coal: mid-Desmoinesian Stage,
upper Middle Pennsylvanian.
Centralia Underground Coal
Fire
- heat from the burning coal bed has killed these trees along the failed
interception trench. Some have been scorched black.
Centralia Underground Coal
Fire
- smoking vents have been and still are common along the walls of the
interception trench. Unusual minerals litter the ground in the vicinity
of the vents.
Centralia Underground Coal
Fire
- another vent area.
Several minerals occur in
the Centralia Interception Trench. Some are unidentified.
Identified minerals include native sulfur (S), tschermigite ((NH4)Al(SO4)2·12H2O)
& apjohnite (MnAl2(SO4)4·22H2O);
the latter two minerals are very rare. The above photo shows several
rocks & burned wood with encrusting sulfur crystals (yellow). The
white specimens may be tschermigite and/or apjohnite. I don't know what
the red stuff is. Many of these specimens were quite hot when
collected. My students laughed at me for wearing oven mitts at this
locality, but they soon realized why.
Unidentified red
sulfur-bearing mineral from coal fire vent at Centralia Interception Trench.
Burned wood with encrusting
sulfur crystals, from the Centralia Interception Trench. How does the
sulfur form? The coal bed has a minor component of sulfur (in the form of
sulfide minerals, sulfate minerals, or S-bearing organic matter). The
rod-shaped, flagellated, hydrogen-scavenging proteobacterium Desulfovibrio
desulfuricans (Beijerinck, 1895) can convert sulfate minerals into
hydrogen sulfide gas (H2S). When released at the surface, the
hydrogen sulfide gas oxidizes, and sulfur crystals form.
Seeing the ground on fire is
something one doesn't quickly forget.
Some mineral info. provided
by Matt Livingood, Jason Winicaties, and Jared Stein.
CENTRALIA GHOST
TOWN
The underground coal fire at
Centralia started in 1962. For many years, smoke & fumes have risen
from yards, streets, and people's basements. Folks started moving out in
the late 1960s. Attempts to put out the fire failed.
In early 1981, a smoking
sinkhole formed underneath a young boy, and he sank down to his waist. He
tried wriggling out, but a larger, deeper hole formed around him. He hung
on to plant roots at about 3' down to keep from falling further. His cousin
was yards away, and came to his rescue. The smoke was so dense that the
cousin could barely see the kid's red cap only three feet down. He
grabbed blindly into the hole & dragged the boy out.
Most Centralia families left
after this incident, which made national headlines. Centralia is now a
ghost town - the last Centralia residents left in early 2010. Before
then, an occasional standing house could still be seen in “town”.
Centralia now consists of
abandoned, overgrown streets and alleyways, with sidewalks and front steps
leading nowhere.
