DC pole | Wartość | Język |
dc.contributor.author | Gumsley, Ashley | - |
dc.contributor.author | Stamsnijder, Joaen | - |
dc.contributor.author | Larsson, Emilie | - |
dc.contributor.author | Söderlund, Ulf | - |
dc.contributor.author | Naeraa, Tomas | - |
dc.contributor.author | de Kock, Michiel | - |
dc.contributor.author | Sałacińska, Anna | - |
dc.contributor.author | Gawęda, Aleksandra | - |
dc.contributor.author | Humbert, Fabien | - |
dc.contributor.author | Ernst, Richard | - |
dc.date.accessioned | 2020-04-24T08:19:48Z | - |
dc.date.available | 2020-04-24T08:19:48Z | - |
dc.date.issued | 2020 | - |
dc.identifier.citation | "Geological Society of America Bulletin" (2020) | pl_PL |
dc.identifier.issn | 1943-2674 | - |
dc.identifier.uri | http://hdl.handle.net/20.500.12128/13648 | - |
dc.description.abstract | U-Pb geochronology on baddeleyite is a
powerful technique that can be applied effectively
to chronostratigraphy. In southern
Africa, the Kaapvaal Craton hosts a wellpreserved
Mesoarchean to Paleoproterozoic
geological record, including the Neoarchean
Ventersdorp Supergroup. It overlies the Witwatersrand
Supergroup and its world-class
gold deposits. The Ventersdorp Supergroup
comprises the Klipriviersberg Group, Platberg
Group, and Pniel Group. However, the
exact timing of formation of the Ventersdorp
Supergroup is controversial. Here we present
2789 ± 4 Ma and 2787 ± 2 Ma U-Pb isotope dilution-
thermal ionization mass spectrometry
(ID-TIMS) baddeleyite ages and geochemistry
on mafic sills intruding the Witwatersrand Supergroup,
and we interpret these sills as feeders
to the overlying Klipriviersberg Group
flood basalts. This constrains the age of the
Witwatersrand Supergroup and gold mineralization
to at least ca. 2.79 Ga. We also report
2729 ± 5 Ma and 2724 ± 7 Ma U-Pb ID-TIMS
baddeleyite ages and geochemistry from a
mafic sill intruding the Pongola Supergroup
and on an east-northeast–trending mafic dike,
respectively. These new ages distinguish two
of the Ventersdorp Supergroup magmatic
events: the Klipriviersberg and Platberg. The
Ventersdorp Supergroup can now be shown
to initiate and terminate with two large igneous
provinces (LIPs), the Klipriviersberg
and Allanridge, which are separated by Platberg
volcanism and sedimentation. The age
of the Klipriviersberg LIP is 2791–2779 Ma,
and Platberg volcanism occurred at 2754–
2709 Ma. The Allanridge LIP occurred between
2709–2683 Ma. Klipriviersberg, Platberg,
and Allanridge magmatism may be
genetically related to mantle plume(s). Higher
heat flow and crustal melting resulted as a
mantle plume impinged below the Kaapvaal
Craton lithosphere, and this was associated
with rifting and the formation of LIPs. | pl_PL |
dc.language.iso | en | pl_PL |
dc.rights | Uznanie autorstwa 3.0 Polska | * |
dc.rights.uri | http://creativecommons.org/licenses/by/3.0/pl/ | * |
dc.subject | neoarchen | pl_PL |
dc.subject | Kaapvaal Craton | pl_PL |
dc.subject | Africa | pl_PL |
dc.subject | Ventersdorp Supergroup | pl_PL |
dc.title | Neoarchean large igneous provinces on the Kaapvaal Craton in southern Africa re-define the formation of the Ventersdorp Supergroup and its temporal equivalents | pl_PL |
dc.type | info:eu-repo/semantics/article | pl_PL |
dc.identifier.doi | 10.1130/B35237.1 | - |
Pojawia się w kolekcji: | Artykuły (WNP)
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