Showing papers by "Pascal Gente published in 1996"

Volcanic growth faults and the origin of Pacific abyssal hills

Abstract: The topographic features known as abyssal hills characterize >30% of the ocean floor, and yet their origin has been the subject of vigorous debate for over 40 years. Submersible-based investigations show that Pacific abyssal hills are created on the flanks of the East Pacific Rise as horsts and grabens which lengthen with time. Hills are bounded on one side by ridge-facing scarps produced by normal faulting, and on the other by more gentle slopes produced by volcanic growth faulting.

Oceanic transverse ridges: A flexural response to fracture-zone–normal extension

Abstract: One of the most puzzling characteristics of sea-floor morphology is the occurrence of anomalously shallow, fracture-zone–parallel, oceanic transverse ridges. A model is proposed for the formation of transverse ridges near lat 21° and 24°N on the Mid-Atlantic Ridge in which the differential responses of large-offset and small-offset fracture zones to recent changes in spreading direction result in the generation of normal faults that coincide with the off-axis traces of fracture zones. Numerical models of the flexural response of the lithosphere to normal faulting suggest that modest amounts of extension (<5 km) along low-angle faults (<45°) are responsible for the transverse ridges.