NNW-SSE
extensional fault systems expose the mineralization and tilted all the succession prior to the emplacement of a ~24 Ma ignimbrite package.
The Ainslie Detachment: a regional flat-lying
extensional fault in the Carboniferous evaporitic Maritimes Basin of Nova Scotia, Canada.
From tectonic point of view, the numerous fissures observed are parallel to the active
extensional fault responsible for the local seismicity.
According Lay, as the leading edge of the oceanic plate sinks into the mantle, it pulls on the rest of the plate, bending it downward and causing it to break along the
extensional fault.
McClay, "
Extensional fault segmentation and linkages, Bonaparte Basin, outer North West Shelf, Australia," AAPG Bulletin, vol.
Lynch and Tremblay (1994) and Lynch and Giles (1996) proposed the extensional Ainslie detachment, a large low-angle
extensional fault localized near the base of the Windsor Group in the western Cape Breton Highlands, detected by a layer of calc-mylonite and a stratigraphic gap within the Windsor Group.
Lima, "Structural and petrophysical evolution of
extensional fault zones in low-porosity, poorly lithified sandstones of the Barreiras Formation, NE Brazil," Journal of Structural Geology, vol.
(2008): The Baza Fault: a major active
extensional fault in the Central Betic Cordillera (South Spain).
Following Fyson (1967), Lynch and Tremblay (1994) further proposed that extensional deformation within the Maritimes Basin is not limited to the Margaree Shear Zone, but reoccurred during the late Namurian-early Westphalian with the development of a regional flat-lying
extensional fault (the Ainslie Detachment) that developed within the basin fill.
This anomalous oblique to transverse trend of the contractional structures could be attributed to the reactivation of transfer faults of the Mesozoic
extensional fault system.
It resulted in the formation of deep
extensional faults representing favorable conduits for thermal fluids migration from the deep basin.
In figure 3a we can observe the Riedel faults intersecting previous
extensional faults around the Lempa basin, generated by the transtensional strain regime.