New Scotland Formation
Andrew Leslie & Julie Hanlon

 
New Scotland Localities

Route 9, Coxsackie

Route 23, west of Catskill 

Route 199, Kingston

 Stratigraphy

The New Scotland facies was once the outer shelf of the Helderberg Sea during the Lower Devonian (400 million years ago).  The formation ranges from 60 - 60 feet thick in the Scoharie Valley to a maximum of 140 feet thick in northwest New Jersey.  The bedding occurs in cycles:  mudstone capped with thin chert and pebbles fading upward into a shell bed capped with a mud layer then a massive limestone layer followed by a cherty bed.   The cycle is then repeated.  Large nodules and massive beds with calcareous and argillaceous strata are also characteristic.  In addition, New Scotland contains over 300 species of invertebrates.  These fossils, especially brachiopods, occur in concentrated beds.  

Amalgam of bryozoans with Rhipodemella brachiopod lower left. 

 
Fossils of New Scotland:
Strophonella
Leptaena
Crynoid cross section
young Strophonella

 
The fossils of the New Scotland formation are characteristic of a Devonian shallow sea.  Brachiopods, crinoids, rugose corals, and trilobites are all found throughout the formation.  The most common fossils I found were large strophomenid brachiopods such as Leptaena and Strophonella.  These organisms lived in quiet waters with a broad flat concavo-convex shell with fine linear and arcuate markings.  Strophomenids are commonly used as index fossils for the Devonian period.  Other orders of brachiopods present include smaller orthid brachiopods such as Isorthis, and spiriferid brachiopods like Eospirifer and Atrypa.  Corals are also common, and I found a large rugose coral that had been cracked open to expose the septa.  I also found a number of crinoid stem fragments and bryozoans.  Overall the fauna of the New Scotland formation are essentially filter-feeding invertebrates typical of quiet, offshore waters.

Links:

Silurian:  http://www.ucmp.berkeley.edu/silurian/silurian.html

Devonian:  http://www.ucmp.berkeley.edu/devonian/devonian.html

Contemporary of New Scotland:  http://www.fallsoftheohio.org/virtualtour/start.html

Pictures of Devonian fauna:  http://seaborg.nmu.edu/earth/Devonian.html

Stratigraphy of New York:  http://www.hartwick.edu/geology/work/VFT-so-far/stop4/strat2.html

Devonian maps:  http://vishnu.glg.nau.edu/rcb/Devonian.html

Devonian life:  http://www.gpc.peachnet.edu/~pgore/geology/geo102/devonian.htm

Trilobites:  http://www.aloha.net/~smgon/ordersofttrilobites.htm


 

 
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