The Catamaran Fault cuts pre-Carboniferous rocks of the Miramichi Geanticline in north-central New Brunswick. It has been examined for about 60 miles (100 km) across the intrusive and metamorphic core of the geanticline and into the Siluro-Devonian flank rocks. The fault strikes easterly in the core and northeasterly in the flanks.Where displacement could be determined movement on the fault is mainly right lateral strike-slip. There is no evidence for major dip-slip. Fracture analysis indicates that faulting was in response to a northwest-southeast trending principal compressive stress similar to that deduced for other faults in the Maritime Provinces. Latest movement along the fault was post-Middle Devonian (i.e. post-dates the emplacement of the Acadian granite) and pre-Pennsylvanian.The Catamaran Fault may extend eastward along a fault possibly underlying Miramichi Bay and continuing under the Gulf of St. Lawrence, and westward along a southwesterly trending fault in western New Brunswick. As such the Catamaran Fault may exceed 250 miles (400 km) in length.