TRENTON/BLACK RIVER DOLOMITE
In the past decade, over twenty new natural gas fields have been discovered in isolated dolomite bodies located in south-central New York. These bodies occur as long, linear features in the Upper Ordovician Black River Limestone. They appear as structural lows, or sags, on seismic profiles and are associated with deep rooted fault systems. These dolomite bodies form when hot, magnesium-rich fluids travel upward along faults to shallower depths where they dissolve the surrounding limestone and precipitate dolomite. This process can create void spaces, known as vugs, which may later become filled with oil or gas.