Fossils in the Tunkhannock Creek Watershed
Although the Earth is
approximately 4.5 billion years old, rocks aged at approximately 3.7 billion
years found in Africa and Greenland show traces of life.
The oldest rocks in Pennsylvania are up to 1.6 billion years old; hence
all rocks in Pennsylvania were formed after life first appeared on the planet.
Unfortunately, our area of
Northeastern Pennsylvania is relatively poor in fossils compared to the coalbed
areas of Lackawanna and Luzerne Counties, where plant fossils are abundant.
Fossils associated with coal deposits include scale trees, scouring
rushes, rushes, ferns, and seed ferns. Excellent
examples of some of these can be seen at the Anthracite Museum in Scranton.
Marine fossils are rare in this
area because the Lock Haven Formation was deposited under presumed low salinity
of the water and and also because of the rapid influx of muds and silts being delivered from the
nearby Catskill delta.
The Lock Haven Formation is found
in only a few localities in the Tunkhannock Creek Watershed area. Below
are examples of fossilized organisms which might be found in rocks from this
formation. However, it does outcrop in several areas just outside the
watershed, notably in Great Bend along the Susquehanna River and in the Meshoppen Creek drainage.
Cyrtospirifer and Ptychomaletoechia
are brachiopods. Crinoid
stem fragments are common fossils.