|Morphology and tectonics of the Galapagos Triple Junction|
Searle, R. C.; Francheteau, J. (1986). Morphology and tectonics of the Galapagos Triple Junction. Mar. Geophys. Res. 8(2): 95-129
In: Marine Geophysical Researches. Reidel: Dordrecht. ISSN 0025-3235; e-ISSN 1573-0581
Earth sciences > Geology > Geomorphology
Earth sciences > Geology > Tectonics
Exploration > Geophysical exploration
Topography > Topography (geology) > Bottom topography
|Auteurs|| || Top |
- Searle, R. C.
- Francheteau, J.
The authors describe the results of GLORIA and Sea Beam surveys, supplemented by other marine geophysical data, of the Galapagos Triple Junction where the Pacific, Cocos and Nazca plates meet. The data allowed detailed topographic and tectonic maps of the area to be produced. They located each spreading axis with a precision of about 1 km. All 3 plate boundaries change character as the triple junction is approached to take on morphologies typical of slower spreading axes. The axis of the East Pacific Rise was found to be completely continuous throughout the survey area, where it runs along the 102 degree 05' W meridian. The Cocos-Nazca axis, however, fails to meet it, leaving a 20-km-wide band of apparently normal East Pacific Rise crust between its tip and the East Pacific Rise axis. As a consequence there must be considerable intra-plate deformation within the Cocos and Nazca plates. A further 40 km of the Cocos-Nazca axis is characterised by oblique faulting that they interpret to be a sign of rifting of pre-existing East Pacific Rise crust.