It is a dome-shaped region approximately 10 miles (16 km) across and rising about 14,000 feet (4,267 m) from the sea floor.

It is located at approximately 30°8′N latitude 42°8′W longitude; just east of the intersection of the Mid-Atlantic Ridge with the Atlantis Transform Fault.

Geologic studies of the massif have indicated that it is not composed of the black basalt typical of the ocean floor but rather of dense green peridotite, which is usually found in the mantle.

The central dome is corrugated and striated in a way that is representative of an exposed ultramafic oceanic core complex.

It found that a steeply sloping detachment fault is associated with the oceanic core complex structure.