The seamount lies in the southern Rockall Trough,[2] at the foot of the Scottish continental slope and 166 kilometres (103 mi) west-southwest of Barra Head, Hebrides.

[12] Rocks dredged from Hebrides Terrace Seamount have a tholeiitic[13] basaltic composition and define two separate suites, one aluminium-rich and the other aluminium-poor.

[14] The seamount is the location of a positive gravity anomaly that is thought to indicate the presence of a 17 kilometres (11 mi) thick igneous body.

[2] On 13 April 1980 a ML 3.5 earthquake[21] occurred just west of Hebrides Terrace Seamount;[22] it was probably not an underwater explosion and may have been instead caused by movements along a local fault.

[26] The faunal communities vary depending on the depth, the substrate (bedrock, cobbles, corals, gravel and sand), the nature of the watermass surrounding them[27] and internal tides which modulate the nutrient supply.

[29] The complicated oceanographic regime may facilitate the concentration of nutrients at the seamount, enabling the development of rich biological communities.

[2] Fish species encountered at Hebrides Terrace Seamount include Atlantic codling, false boarfish and roundnose grenadier.