Before Pangaea (the supercontinent that existed 300-100 million years ago), there was another supercontinent called Rodinia (which means The Motherland in Russian). Rodinia existed 1,100-750 million years ago in a geologic eon referred to as the Precambrian, which classes all geologic time periods from the formation of the Earth 4.55 billion years ago until 543 million years ago, when the Paleozoic era began.
Like all great supercontinents, Rodinia eventually succumbed to the forces of continental weakening and eventual break-up as hot magma formed under the supercontinent, ultimately resulting in thinning and extension of the mantle and rifting of the continental crust above. In the predecessor land mass of Laurentia (which is present day North America), these same forces eventually caused a series of failed and successful rifts to form roughly parallel to the present-day Appalachian Mountains.
The successful rifts formed to the southeast of the Appalachians, closer to the present-day Atlantic coastline. The failed rifts formed further to the west and northwest and have, in recent times, taken on names like the Rome Trough or the Rough Creek Graben, an illustration for which is shown below (courtesy of the Kentucky Geological Society).
These rift structures filled in many places with nearly 20,000 feet of clastic sediment, with basin-fan complexes believed to be fairly prominent depositional sources. While these Precambrian rift basins were subject to significant and complex erosional, tectonic and thermal regimes since their deposition, some explorationists believe that the basins could be prospective for both oil & gas and minerals.
Conoco was one of the E&P operators that was attracted by the region’s potential in the early 1990’s. More recently, a consortium of oil & gas companies – including Chesapeake Energy – engaged with the Kentucky Geological Society to undertake a study of the area’s hydrocarbon potential, with special interest in deep gas and black shale development.
NEOS was recently asked to undertake a study of a 360,000 sqmi area spanning multiple states in the Eastern U.S. where these rift structures were known or believed to be present. There was a particular interest in an area having several contiguous rift blocks with a combined areal extent of 50,000 sqmi.
A topography map (top) and a Total Magnetic Intensity map (bottom) from the study area are shown below. The general area of the Rough Creek Graben is highlighted in both images (white polygon).
Precambrian Rift neoSCAN Study Area (~360,000 sqmi)
Topography map (middle), Total Magnetic Intensity (bottom)
According to Chris Friedemann, Chief Commercial Officer for NEOS,
In roughly 90 days, we were able to identify some of the key structural features that affect hydrocarbon prospectivity in the study area, including sediment thickness and burial depths, basement topography and faulting, and the location of major lineaments and intrusive complexes.
To learn more about the neoSCAN, click here to visit the relevant page on the NEOS web site (including a narrated slideshow describing the offering). To learn more about this project, click here (to read the press release) or send an email to the business developer responsible for the project (Paul Casey) using the function below.