J
F
Last name: JOURDAN
First name: Fred
International audience
The Jurassic Karoo large igneous province consists of vast quantities of basaltic lava-flows, giant dike swarms and poorly dated silicic magmatism. The Karoo magmatism occurred over more than 3x106 km² and was associated with the opening of the Indian Ocean. We present new 40Ar/39Ar geochronological data concerning the easternmost part (i.e....
Continental flood basalts consist of vast quantities of lava, sills and giant dyke swarms that are associated with continental break-up. The commonly radiating geometry of dyke swarms in these provinces is generally interpreted as the result of the stress regime that affected the lithosphere during the initial stage of continental break-up or...
Continental flood basalts consist of vast quantities of lava, sills and giant dyke swarms that are associated with continental break-up. The commonly radiating geometry of dyke swarms in these provinces is generally interpreted as the result of the stress regime that affected the lithosphere during the initial stage of continental break-up or...
40Ar/39Ar geochronology is one of the most important techniques for constraining the timing of basaltic events due to the paucity of suitable minerals in basalts for other geochronological techniques such as U–Pb (e.g., zircon, baddeleyite). Among a variety of materials from basaltic rocks that have been used for 40Ar/39Ar dating, plagioclase...
The peak activities of continental flood basalts are currently considered as huge and brief (1 m.y.) magmatic events, with strong implications for geodynamics and biotic turnover. New 40Ar/39Ar dates on the Karoo flood basalts (southern Africa) show a longer duration of magmatism (8 m.y., with 6 m.y. for the main volume) with an apparent...
The structural organization of a giant mafic dyke swarm, the Okavango complex, in the northern Karoo Large Igneous Province (LIP) of NE Botswana is detailed. This N110°E-oriented dyke swarm extends for 1500 km with a maximum width of 100 km through Archaean basement terranes and Permo-Jurassic sedimentary sequences. The cornerstone of the study...
International audience
Bifacial tools discovered at about a hundred Lower Palaeolithic sites in the Bose Basin, southern China, have been previously dated to around 800,000 years ago. This age was obtained by dating four tektites directly associated with the tools at the Nalai site using the 40 Ar/ 39 Ar method (Michel et al., 2021). Similar ages on tektites from the...