TECTONIC WINDOWS INTO THE OCEANIC LITHOSPHERE

tectonic windows

Locations of tectonic windows and deep drill holes in oceanic crust formed at intermediate to fast rates.

Alvin going in water

HOV Alvin has been used extensively to study the geology of oceanic crust exposed in tectonic windows.

ROV Jason

ROV Jason II permits extended surveys of oceanic crust in tectonic windows.

geocompass

The Geocompass is a simple tool for measuring the orientation (strike and dip) of structures on the deep sea floor.

sheeted dikes on seafloor

Comparison of sheeted dikes formed by seafloor spreading exposed in the Oman Ophiolite (left) and at the Pito Deep Rift (right).

sheeted dikes Hess Deep Rift

Digital mosaic of sheeted dikes exposed on a cliff face at the Hess Deep Rift. Image is about 20 m high.

columnar section faults

Columnar sections summarizing Alvin and Nautile dive data from the N wall of the Blanco Transform Fault (below). Dives were made in the area outlined in the bathymetric map (above).

oceanic crustal structure

Summary of oceanic crustal structure at the Hess Deep Rift (right) based on near-bottom geological investigations in the outlined area in the bathymetric map (above).

crustal structures Pito DeepSummary of oceanic crustal structure at the Pito Deep Rift (right) based on near-bottom geological investigations in the outlined area in the bathymetric map (above).