Towards a complete magmatic barcode for the Zimbabwe craton: Baddeleyite U–Pb dating of regional dolerite dyke swarms and sill complexes

The geochemistry and petrogenesis of the Paleoproterozoic du Chef dyke swarm, Québec, Canada

“…This evidence, along with consistent trace element geochemistry suggests that the du Chef dykes are be the product of mantle plume-driven magmatism as proposed by Buchan (2004) andSöderlund et al (2010). However, alternate models of the cooling of the mantle [e.g., Korenaga (2008) and Abbot et al (1994)] indicate that the du Chef dykes are not the product of an anomalously hot mantle plume.…”

“…Using overlapping U-Pb ages of mafic suites, Söderlund et al (2010) There is a general consensus that the mantle was significantly hotter during the Palaeoproterozoic than it is today (Fig. 10).…”

Baddeleyite U–Pb ages and gechemistry of the 1875–1835 Ma Black Hills Dyke Swarm across north-eastern South Africa: part of a trans-Kalahari Craton back-arc setting?

“…These publications suggested that the name Black Hills Dyke Swarm (BHDS) should be given to NE-trending, c. 1.9 Ga, tholeiitic dykes which cut across this part of the craton in great numbers. In the same special volume, Söderlund et al (2010) dated a pair of Mashonaland sills that were shown to be coeval to Hanson et al's (2004a) post-Waterberg sills, and thereby conclusively linked these two cratons at that time. More recently, Geng et al (2014) constrained a maximum age for more evolved pyroclastic rocks in the uppermost part of the Sibane Formation lavas within the Soutpansberg Group, which will be shown to possibly mark the termination of a c. 1.89-1.83 Ga trans-Kalahari Craton igneous province, initiated by the oldest Mashonaland and Post-Waterberg sills.…”

A new grand mean palaeomagnetic pole for the 1.11 Ga Umkondo large igneous province with implications for palaeogeography and the geomagnetic field

“…This assumption, while shown to be true in this study, is complicated by the spatial overlap of the Umkondo Province with other dolerite intrusions with a range in U-Pb isotopic ages. These include the 1.93 Ga Moshaneng dolerites in Botswana (Hanson et al, 2004b), the 1.88-1.87 Ga Mashonaland Igneous Province in Zimbabwe and coeval dolerites intruding the Waterberg Group in South Africa (Hanson et al, 2004bSöderlund et al, 2010), post-1.83 Ga dolerite sills in the Soutpansberg Group (Brandl, 1981(Brandl, , 1985Geng et al, 2014), and the widespread 0.18 Ga Karoo LIP (Sell et al, 2014). It is a testament to the mild post-2.0 Ga metamorphic history of the interior of the Kalahari Craton that dolerites dated at ca.…”

“…The thick translucent gray line on the inset map indicates the interpreted shape of the Kalahari Craton on the interior of the late Mesoproterozoic orogenic belts that is used in the paleogeographic reconstructions (Fig. 4) (Hanson et al, 2004bSöderlund et al, 2010), post-1.83 Ga dolerite sills in the Soutpansberg Group (Brandl, 1981(Brandl, , 1985Geng et al, 2014), and the widespread 0. basement correspond to the Umkondo event is a reasonable one, it is largely untested since there are precise age constraints for only a small fraction of the total exposed intrusions. If high-quality paleomagnetic data can be generated from a given sill, the distinct paleomagnetic poles from ca.…”