EXTREME VARIATIONS IN SEAFLOOR SPREADING ON THE MID-ATLANTIC RIDGE
Columnar sections of the geology of major escarpments (tectonic windows) in slow-spread oceanic crust (below) from the Central Atlantic and other regions.
Similar style of segmentation and range of extensional tectonic and magmatic structures in the MARK Area (MAR 23°N) and the Turkana (E African) Rift (after Mutter & Karson, 1992).
Columnar section and cross section of the E rift valley wall of the MAR at 22° N (above) and images of (left to right): striated fault surface, photomicrograph of undeformed and cataclastic dike rock.
Cross section of the Atlantis Massif Oceanic Core Complex at 30°N on the MAR.
Serpentinite dredged from the MAR.
Sheared serpentinite from the detachment shear zone atop the Atlantis Massif Oceanic Core Complex.
Gently dipping, coarse debris-slide breccia layer unconformably overlies sheared serpentinite on the top of the Atlantis Oceanic Core Complex.
Carbonate spires >10 m high from the Lost City Hydrothermal Vent Field on the summit of the Atlantis Massif Oceanic Core Complex.
3D bathymetric image of the Atlantis Massif Oceanic Core Complex (Cheadle & Grimes, 2010)
3D bathymetric image of the Atlantis Massif Oceanic Core Complex (Cheadle & Grimes, 2010)