Search > BIRPS GRID Survey > Filtered GRID 4 and 17, perspective view Regional Project


Click here for high resolution image [jpeg, 3.2 MB]

Filtered GRID 4 and 17, perspective view interpreted Interpretation

VSA Author: Taija Torvela
Date Created: 2010-11-15

The image shows the interpreted Moho (green), the upper limit of the Flannan reflector (purple; e.g. Brewer & Smythe, 1984) and of the Outer Isles Thrust (blue; e.g. Brewer & Smythe, 1984). In the area of the profiles, the OIT terminates before reaching the sea floor, being offset by and/or reactivated as normal faults during rifting. Note how the OIT becomes steeper toward the south and reaches closer to the seafloor; this geometry is probably also due to normal faulting combined with block rotation. The normal fault interpretations are not shown in this image. The convex-upward "antiform" geometry of the Flannan reflector (sometimes called Flannan Thrust of Flannan Fault) is clearly imaged. The FR is a wide shear zone reaching down into the mantle (e.g. Brewer & Smythe, 1984; Warner & McGeary 2007). It has been mostly interpreted a compressional feature, a Caledonian Thrust (e.g. Brewer & Smythe, 1984), although it has been suggested to be a mantle extensional feature (Reston, 1990). The Moine Thrust zone in the eastern part of the GRID 17 is not interpreted here. See the Survey docs & links for a location map.





Details:

  • Interpretation Administrator:
    • Taija Torvela
  • VSA Author:
    • Taija Torvela

Geological Interpretation

Deformation Structures
Linked Contraction-Extension, Thrusts, Negative

Basement
Moho, Continental Crust

Geological Context

Plate Settings and Margins
Orogenic belts

Tectonics
Orogenic Belt

Basin Setting
Passive Margin

Geographic Context

Physical Geography
Shelves

Political Geography
United Kingdom of Great Britain & Northern Ireland

Geophysics

Survey Information
Marine, Multichannel 2D, >10s

Data Presentation
Vertical Scale - Time, Amplitude

Image Type
Vertical Profile