Undercrusting by serpentinite beneath rifted margins

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doi: 10.1038/341523a0
Author(s): Boillot, Gilbert; Féraud, Gilbert; Recq, Maurice; Girardeau, Jacques
Author Affiliation(s): Primary:
Lab. Géodynamique Sous-Mar., Obs. Océanol., Villefranche-sur-Mer, France
Other:
Univ. Nice, France
Univ. Pierre et Marie Curie, France
Univ. Paris, France
Volume Title: Nature (London)
Source: Nature (London), 341(6242), p.523-525. Publisher: Macmillan Journals, London, United Kingdom. ISSN: 0028-0836 CODEN: NATUAS
Note: In English. 24 refs.; illus. incl. sketch map
Summary: Petrological analyses of sampled serpentinized peridotite from the belt which bounds the W Galicia passive margin, Spain, are discussed. 40 Ar/ 39 Ar dating results of high-T ductile shearing of a diorite dyke traversing the peridotite are presented, with the regional seismic stratigraphy. The results show that uplift, ductile shearing and pervasive serpentinization of mantle rocks occurred during early Cretaceous rifting of the margin. The seismic crust beneath the rifted margin here may include mantle material changed into serpentinite by syn-rift hydrothermal activity.
Year of Publication: 1989
Research Program: ODP Ocean Drilling Program
Key Words: 03 Geochronology; 05 Petrology, Igneous and Metamorphic; 18 Geophysics, Solid-Earth; Absolute age; Amphibole group; Ar/Ar; Atlantic Ocean; Chain silicates; Continental margin; Cretaceous; Crust; Dates; Dikes; Diorites; Distribution; Europe; European Atlantic; Feldspar group; Framework silicates; Galicia Spain; Geochronology; Geophysical methods; Geophysical surveys; Iberian Peninsula; Igneous rocks; Intrusions; Leg 103; Lower Cretaceous; Mesozoic; Metaigneous rocks; Metamorphic rocks; Metasomatic rocks; Metasomatism; North Atlantic; ODP Site 637; Ocean Drilling Program; Oceanography; Passive margins; Peridotites; Plagioclase; Plutonic rocks; Processes; Rifting; Seismic methods; Serpentinite; Serpentinization; Shear zones; Silicates; Southern Europe; Spain; Surveys; Ultramafics
Coordinates: N410000 N440000 W0100000 W0133000
Record ID: 1989079353
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from Mineralogical Abstracts, United Kingdom, Twickenham, United Kingdom