Rockall Helen's Reef (the latter was named in 1830). Notes Bibliography Rockall Rockall () is a British uninhabited granite islet located within the exclusive economic zone (EEZ) of the United Kingdom, situated in the North Atlantic Ocean. Its approximate distances from the closest large islands are: west of Scotland; northwest of Ireland; and 700 km (440 miles) south of Iceland. The nearest permanently inhabited place is North Uist, an island in the Outer Hebrides of Scotland, 370 km (230 miles) to the east. The United Kingdom claimed Rockall in 1955 and incorporated it as a part of Scotland in 1972. Ireland
Nankai Trough This was concluded by Kanda et al., 2004, through inversion analysis of seismic data. Historically, the most recent large-scale earthquake to occur in the Nankai Trough was in 1944 off the Kii Peninsula. Using recent ocean bottom seismograph studies, it has been determined that most of the seismicity occurs near the trough axis (Obana et al., 2006). Along the western area of the Nankai Trough, seismicity appears to be related to irregularities in crustal structure such as fractures generated from the subducted seafloor, including backarc basin crust of the Shikoku Basin, as well as due to serpentization of uppermost mantle