https://vital.seals.ac.za/vital/access/manager/Index en-us 5 Supplying lava eruptions in the Karoo Province, South Africa: a geochemical comparison of the volcanic sequence with intrusions in the main Karoo basin https://vital.seals.ac.za/vital/access/manager/Repository/vital:36901 Mon 13 May 2024 13:14:09 SAST ]]> The Klinghardt phonolites, South West Africa: Tertiary volcanism in western southern Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:29627 Mon 13 May 2024 12:53:26 SAST ]]> The timing and duration of the Karoo igneous event, southern Gondwana https://vital.seals.ac.za/vital/access/manager/Repository/vital:38857 Mon 13 May 2024 12:53:23 SAST ]]> The Luderitz Alkaline Province, South West Africa II: metasomatism and assimilation in the contact aureole of the Granitberg Foyaite Complex https://vital.seals.ac.za/vital/access/manager/Repository/vital:36913 Mon 13 May 2024 12:50:33 SAST ]]> The Luderitz Alkaline Province, South West Africa I: descriptive petrology of the Granitberg Foyaite Complex https://vital.seals.ac.za/vital/access/manager/Repository/vital:36912 Mon 13 May 2024 12:50:14 SAST ]]> The Lüderitz alkaline province, South West Africa, III: the Pomona and Drachenberg Syenite Complexes https://vital.seals.ac.za/vital/access/manager/Repository/vital:36915 Mon 13 May 2024 12:48:03 SAST ]]> New chemical analyses of the Suurberg volcanic rocks and their significance in relation to Mesozoic volcanism in Southern Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:36951 Mon 13 May 2024 12:47:23 SAST ]]> Tertiary phonolite volcanism in the Klinghardt Mountains of South West Africa/Namibia https://vital.seals.ac.za/vital/access/manager/Repository/vital:36953 Mon 13 May 2024 12:46:55 SAST ]]> Petrogenesis of Karoo magmas from Namibia and the nature of their source areas https://vital.seals.ac.za/vital/access/manager/Repository/vital:29831 Mon 13 May 2024 12:46:10 SAST ]]> The geochemistry of basic volcanics of the Dordabis Formation northeast of Dordabis and their significance for correlations within, and evolution of, the Rehoboth Magmatic Arc https://vital.seals.ac.za/vital/access/manager/Repository/vital:29577 Mon 13 May 2024 12:46:09 SAST ]]> Evolution of the continental lithosphere: evidence from volcanics and xenoliths in southern Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:36989 Mon 13 May 2024 12:44:43 SAST ]]> The role of continental lithosphere in the generation of the Karoo volcanic rocks: evidence from combined Nd-and Sr-isotope studies https://vital.seals.ac.za/vital/access/manager/Repository/vital:37080 Mon 13 May 2024 12:44:13 SAST ]]> Strontium isotope characterization of Karoo volcanic rocks https://vital.seals.ac.za/vital/access/manager/Repository/vital:37081 Mon 13 May 2024 12:43:32 SAST ]]> Regional geochemistry of the Karoo igneous province https://vital.seals.ac.za/vital/access/manager/Repository/vital:37079 Mon 13 May 2024 12:43:09 SAST ]]> Karoo basalts of the Springbok Flats: geochemistry and correlation https://vital.seals.ac.za/vital/access/manager/Repository/vital:36706 Mon 13 May 2024 12:42:45 SAST ]]> Geochemistry of Karoo basalts and dolerites in the northeastern Orange Free State: Recognition and origin of the new Karoo basalt magma types. https://vital.seals.ac.za/vital/access/manager/Repository/vital:29830 Mon 13 May 2024 12:42:20 SAST ]]> Geochemistry and petrogenesis of the Etendeka volcanic rocks from SWA Namibia https://vital.seals.ac.za/vital/access/manager/Repository/vital:37041 Mon 13 May 2024 12:41:13 SAST ]]> The late Archaean Dominion Group, South Africa: petrogenesis of flood-type basalts and their mantle sources https://vital.seals.ac.za/vital/access/manager/Repository/vital:36721 Mon 13 May 2024 12:38:37 SAST ]]> Distribution and petrogenesis of the basic rocks of the Etendeka Formation of northwestern Namibia https://vital.seals.ac.za/vital/access/manager/Repository/vital:36709 Mon 13 May 2024 12:37:55 SAST ]]> A laterally extensive geochemical discontinuity in the subcontinental Gondwana Lithosphere https://vital.seals.ac.za/vital/access/manager/Repository/vital:36710 Mon 13 May 2024 12:37:22 SAST ]]> Tying up the continents https://vital.seals.ac.za/vital/access/manager/Repository/vital:38220 Mon 13 May 2024 12:36:57 SAST ]]> MORB-related dolerites associated with the final phases of Karoo flood basalt volcanism in southern Africa. https://vital.seals.ac.za/vital/access/manager/Repository/vital:38222 Mon 13 May 2024 12:35:03 SAST ]]> Preliminary geochemical data for dolerite dykes and sills of the southern part of the Etendeka Igneous Province https://vital.seals.ac.za/vital/access/manager/Repository/vital:36803 Mon 13 May 2024 12:34:17 SAST ]]> Promotion of the Etendeka Formation to Group status: a new integrated stratigraphy https://vital.seals.ac.za/vital/access/manager/Repository/vital:38442 Mon 13 May 2024 12:33:38 SAST ]]> Karoo and Etendeks flood basalt provinces, southern Africa and the tectonic development of their adjacent margins: https://vital.seals.ac.za/vital/access/manager/Repository/vital:38386 Mon 13 May 2024 12:33:13 SAST ]]> Geology Field Trip Guide: Natural Sciences and Geography Educators visit https://vital.seals.ac.za/vital/access/manager/Repository/vital:38387 Mon 13 May 2024 12:32:49 SAST ]]> Geochemical stratigraphy of the Mohale Dame-Katse Dam areas, Lesotho. Report on contract LHDA, Mohale Tunnel: Sampling and Testing of Cores. Lesotho Highlands Tunnel Partnership (Mohale) https://vital.seals.ac.za/vital/access/manager/Repository/vital:38385 Mon 13 May 2024 12:32:30 SAST ]]> Alkaline rocks in the Kuboos-Bremen Igneous Province, southern Namibia: the Grootpenseiland and Marinkas Kwela Complexes https://vital.seals.ac.za/vital/access/manager/Repository/vital:38471 Mon 13 May 2024 12:32:01 SAST ]]> The petrology and significance of a stratiform mafic segregation pegmatite in a Karoo-aged dolerite sheet https://vital.seals.ac.za/vital/access/manager/Repository/vital:38858 Mon 13 May 2024 12:31:15 SAST ]]> Geochemical variations in a long Karoo dyke, Eastern Cape https://vital.seals.ac.za/vital/access/manager/Repository/vital:38877 Mon 13 May 2024 12:30:04 SAST ]]> Excursion to Granitberg and the Klinghardt Mountains, southern Namibia https://vital.seals.ac.za/vital/access/manager/Repository/vital:36801 Mon 13 May 2024 12:29:36 SAST ]]> Field Trip A1: Karoo dykes, sills and volcanics in the Eastern Cape https://vital.seals.ac.za/vital/access/manager/Repository/vital:38383 Mon 13 May 2024 12:28:46 SAST ]]> New views on the Jurassic Clarens Formation: volcano-sedimentary interaction https://vital.seals.ac.za/vital/access/manager/Repository/vital:36874 Mon 13 May 2024 12:28:06 SAST ]]> Magma flow inferred from AMS fabrics in a layered mafic sill, Insizwa, South Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:6733 1000-m-thick layered mafic intrusion, part of the Karoo Igneous Province in South Africa. The peridotitic and gabbronoritic rocks are undeformed and mineral fabrics demonstrably result from magma flow. A horizontal, centimeter-scale model layering is visible in numerous outcrops. Plagioclase crystals are both tabular and elongated. Their preferred orientation, parallel to the layering, forms a foliation and a NW–SE lineation, respectively interpreted as the magma flow plane and flow direction. Throughout the 78 stations of this study (699 specimens), magnetic susceptibilities (K[subscript m]) range from 750 to 10,000×10[superscript (−6)] SI. The magnetic anisotropy (P[subscript j]) ranges from 1.03 to 1.08. Magnetic ellipsoids are both prolate and oblate (average T[subscript j]≈0). Anisotropy of magnetic susceptibility (AMS) fabrics are dominated by multidomain to pseudo-single domain magnetite. High-field magnetic experiments indicate that the paramagnetic contribution from the mafic silicates is less than 50 percentage for low susceptibility rock types. The anisotropy results from magnetite grain shape solely as shown by no significant increase in P[subscript j] with increasing K[subscript m]. The magnetic lineation (305°, 05°) is consistent throughout the sill at various scales and coincides with the mineral lineation in average. In contrast, the magnetic foliation (125° NE 10°) is generally perpendicular to the mineral foliation and to the layering. Several explanations for this odd configuration are discussed. The variations of magnetic parameters across the layering and field observations point to a multiple injection. The magnetic lineation is consistent with the presence of a single feeder dike situated to the SE of the sill.]]> Mon 13 May 2024 12:16:05 SAST ]]> Review of South African research on volcanic and related rocks and mantle-derived materials : 1999-2002 https://vital.seals.ac.za/vital/access/manager/Repository/vital:6737 Mon 13 May 2024 12:13:17 SAST ]]> Rare earth element geochemistry of the Insizwa lobe of the Mount Ayliff Complex, Eastern Cape, South Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:6736 Mon 13 May 2024 12:11:26 SAST ]]> The Karoo igneous province: https://vital.seals.ac.za/vital/access/manager/Repository/vital:38413 Mon 13 May 2024 12:09:43 SAST ]]> The emplacement of class 1 kimberlites: part 2, petrographic evidence https://vital.seals.ac.za/vital/access/manager/Repository/vital:36878 Mon 13 May 2024 12:09:20 SAST ]]> The emplacement of class 1 kimberlites: part 1, evidence of geological features https://vital.seals.ac.za/vital/access/manager/Repository/vital:36877 Mon 13 May 2024 12:08:56 SAST ]]> The Dominion Group: https://vital.seals.ac.za/vital/access/manager/Repository/vital:38412 Mon 13 May 2024 12:08:34 SAST ]]> Dyke swarms and associated lava formations in the northern Lebombo monocline, Karoo Large Igneous Province, South Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:36880 Mon 13 May 2024 12:07:44 SAST ]]> Rock magnetic stratigraphy of a mafic layered sill: a key to the Karoo volcanics plumbing system https://vital.seals.ac.za/vital/access/manager/Repository/vital:38389 Mon 13 May 2024 12:06:59 SAST ]]> Compositionally diverse magmas erupted close together in space and time within a Karoo flood basalt crater complex: https://vital.seals.ac.za/vital/access/manager/Repository/vital:38396 40 km2 filled by 9–18 km3 of volcaniclastic debris.]]> Mon 13 May 2024 12:06:37 SAST ]]> The geochemistry and evolution of Palaeogene phonolites, central Namibia: https://vital.seals.ac.za/vital/access/manager/Repository/vital:38399 Mon 13 May 2024 12:05:37 SAST ]]> Cretaceous volcanic rocks of the Namibe Basin, southern Angola: report on a reconnaissance field and geochemical investigation https://vital.seals.ac.za/vital/access/manager/Repository/vital:29070 Mon 13 May 2024 12:05:14 SAST ]]> Report on the Mesozoic volcanic and intrusive rocks on the Namibe Basin, Southwest Angola: https://vital.seals.ac.za/vital/access/manager/Repository/vital:38384 Mon 13 May 2024 12:04:49 SAST ]]> An attempt to constrain the age, duration, and eruptive history of the Karoo flood basalt: Naude's Nek section (South Africa) https://vital.seals.ac.za/vital/access/manager/Repository/vital:38401 Mon 13 May 2024 12:04:31 SAST ]]> Karoo volcanic and intrusive rocks: Lesotho and Eastern Cape https://vital.seals.ac.za/vital/access/manager/Repository/vital:38388 Mon 13 May 2024 12:03:37 SAST ]]> The oxygen isotope composition of Karoo and Etendeka picrites: High δ18O mantle or crustal contamination? https://vital.seals.ac.za/vital/access/manager/Repository/vital:27829 Mon 13 May 2024 12:03:12 SAST ]]> The Bero Volcanic Complex: extension of the Paraná-Etendeka Igneous Province into SW Angola https://vital.seals.ac.za/vital/access/manager/Repository/vital:27827 Mon 13 May 2024 12:02:51 SAST ]]> Karoo dolerite intrusions: shaping the landscapes of the Great Karoo https://vital.seals.ac.za/vital/access/manager/Repository/vital:38409 Mon 13 May 2024 12:02:09 SAST ]]> Eruptive history of the Karoo lava flows and their impact on early Jurassic environmental change: https://vital.seals.ac.za/vital/access/manager/Repository/vital:38408 Mon 13 May 2024 12:01:18 SAST ]]> Sub-volcanic intrusions and the link to global climatic and environmental changes: https://vital.seals.ac.za/vital/access/manager/Repository/vital:38414 Mon 13 May 2024 12:00:57 SAST ]]> Emplacement of inflated Pāhoehoe flows in the Naude’s Nek Pass, Lesotho remnant, Karoo continental flood basalt province: use of flow-lobe tumuli in understanding flood basalt emplacement https://vital.seals.ac.za/vital/access/manager/Repository/vital:27826 Mon 13 May 2024 12:00:27 SAST ]]> Base-metal mineralization in alkaline pyroclastics: the Regenstein Vent, South West Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:36950 Mon 13 May 2024 11:49:02 SAST ]]> High-Mg tholeiitic rocks and their significance in the Karroo Central Province https://vital.seals.ac.za/vital/access/manager/Repository/vital:36916 Mon 13 May 2024 11:45:59 SAST ]]> Karoo basalts, South Africa: Petrogenesis and the nature of their mantle rocks https://vital.seals.ac.za/vital/access/manager/Repository/vital:29625 Mon 13 May 2024 11:45:40 SAST ]]> The Karoo igneous province: an introduction https://vital.seals.ac.za/vital/access/manager/Repository/vital:37043 Mon 13 May 2024 11:44:47 SAST ]]> The chemistry and petrogenesis of igneous rocks of the Karoo central area, southern Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:37042 Mon 13 May 2024 11:44:21 SAST ]]> Some geochemical constraints upon models for the crystallization of the upper critical zone-main zone interval, northwestern Bushveld complex https://vital.seals.ac.za/vital/access/manager/Repository/vital:37331 Mon 13 May 2024 11:43:53 SAST ]]> Re-estimation of erosion levels in Group I and II kimberlites between Lesotho, Kimberley and Victoria West, South Africa https://vital.seals.ac.za/vital/access/manager/Repository/vital:36804 Mon 13 May 2024 11:41:24 SAST ]]> Cretaceous erosion in central South Africa: evidence from upper-crustal xenoliths in kimberlite diatremes https://vital.seals.ac.za/vital/access/manager/Repository/vital:38397 Mon 13 May 2024 11:39:08 SAST ]]>