Jurassic to Eocene plate tectonic reconstructions in the Kerguelen Plateau region

We present a series of preliminary reconstructions for the Kerguelen Plateau region from the Late Jurassic to the Eocene that summarize and review the outstanding questions about its plate tectonic evolution. The development of the Indian and adjacent Southern oceans began in Middle to Late Jurassic time with the breakup of Gondwana. Marine magnetic anomalies and limited Deep Sea Drilling Project and Ocean Drilling Program core samples have been used to date the oceanic crust. Fracture zone trends interpreted from satellite (SEASAT and GEOSAT) altimetry, and marine seismic, gravity, and magnetic data have been combined with crustal dates to produce kinematic models of the plates through time. Between the Jurassic and the Late Cretaceous, time controls on the plate tectonic evolution of the region are few. Mesozoic marine magnetic anomalies off the shore of East Africa, Antarctica, and Western Australia document plate motions during the interval; however, extensive areas of oceanic crust from which no anomalies have been identified, including that created during the Cretaceous Long Normal Polarity Interval, and a dearth of fracture zones prevent detailed links with the much better defined plate kinematic synthesis for the past 84 m.y. The Kerguelen Plateau/Broken Ridge complex was emplaced at ~ 110 Ma in a region flanked by Greater India, Australia, and Antarctica. Between then and —43 Ma, when seafloor spreading between the Kerguelen Plateau and Broken Ridge began, our model includes transform motions between the northern and southern sectors of the Kerguelen Plateau.