KIT | KIT-Bibliothek | Impressum | Datenschutz

An AMS study of magma transport and emplacement mechanisms in mafic dykes from the Etendeka Province, Namibia

Wiegand, Miriam 1; Trumbull, Robert B.; Kontny, Agnes 1; Greiling, Reinhard O. 1
1 Institut für Angewandte Geowissenschaften (AGW), Karlsruher Institut für Technologie (KIT)

Abstract:

The Henties Bay Outjo dyke swarm (HOD) in NW Namibia is part of the early Cretaceous Paraná-Etendeka Large Igneous Province. The dykes are dominantly doleritic, compositionally equivalent to the erupted lava series and thus the HOD provides a look at the feeder systems of a flood basalt province. The subvertical dykes mostly strike NE-SW and minor NW-SE, parallel or perpendicular to the Damara Belt in which they intruded. We present a magnetic fabric study using the anisotropies of low-field magnetic susceptibility (AMS) and of anhysteretic remanent magnetization (AARM) with the aim to derive magma flow directions and better constrain emplacement mechanisms within the dyke swarm.

Magnetic susceptibility and its anisotropy in the dykes is mainly controlled by distribution anisotropy of titanomagnetite that mimics the flow-oriented silicate fabric. The anisotropy is low in most samples, supporting a magmatic origin. In 66 of 110 investigated samples the AMS fabric is “normal”, with the κmax axis (inferred flow orientation) within the dyke plane. Most samples yielded vertical to subvertical flow orientations regardless of location near or distant from the former rifted margin. ... mehr


Originalveröffentlichung
DOI: 10.1016/j.tecto.2016.08.016
Scopus
Zitationen: 12
Web of Science
Zitationen: 10
Dimensions
Zitationen: 9
Zugehörige Institution(en) am KIT Institut für Angewandte Geowissenschaften (AGW)
KIT-Zentrum Klima und Umwelt (ZKU)
Publikationstyp Zeitschriftenaufsatz
Publikationsjahr 2016
Sprache Englisch
Identifikator ISSN: 0040-1951, 1879-3266
KITopen-ID: 1000067906
Erschienen in Tectonophysics
Verlag Elsevier
Band 716
Seiten 149-167
Nachgewiesen in Dimensions
Web of Science
Scopus
KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft
KITopen Landing Page