...' of some 300 g u amplitude which is 30 km wide and elongated ENE–WSW, centred on Tunugdliarfik and axially along one of the main zones of Gardar intrusives. This gravity anomaly is similar to that of other ancient rift systems and appears to be a residual of the axial anomaly to be found in modern active...

... Province may also be related to this magmatic activity. The geochemical data lend support to the idea that the Gardar–Abitibi system was a major intracontinental rift zone similar to the present-day East African Rift. The recurrent activity for some 200 million years is consistent with models of a long...

...Alexander Bartels; Troels F. D. Nielsen; Seung Ryeol Lee; Brian G. J. Upton Abstract The Mesoproterozoic Gardar Province in South Greenland developed in a continental rift-related environment. Several alkaline intrusions and associated dyke swarms were emplaced in Archaean and Ketilidian basement...

... Maitre , R.W. , 1989 . A Classification of Igneous Rocks and Glossary of Terms . Blackwell Scientific , Oxford . Macdonald , R. & Upton , B.G.J. 1993 . The Proterozoic Gardar rift zone, south Greenland: comparisons with the East African Rift System . In : Prichard , H.M...

...Sara Ladenburger; Michael A.W. Marks; Brian Upton; Peter Hill; Thomas Wenzel; Gregor Markl Abstract Textural and compositional variations of apatite from rift-related gabbros, syenogabbros, syenites, quartz-syenites, and nepheline syenites of the Mid-Proterozoic Gardar Province (South Greenland...

...Ian M. Coulson; Andrews D. Chambers Abstract The North Qoroq nepheline syenites form part of the rift-related Gardar Province of south Greenland. In situ fractionation of the syenitic magmas resulted in a peralkaline residual magma of lujavritic composition, with concentration of rare-earth...

... the Gardar – Voisey’s Bay fault zone), extending west from the Gardar rift of southern Greenland, orthogonally intersected an older north–south-trending continental suture marked by the Torngat orogen in Labrador. We suggest that the Nain batholith is a mid-crustal equivalent of the subvolcanic alkaline...

... Volcanologique , 38 , 498 – 516 . Macdonald R. Saunders ( 1973 ) Chemical variation in minerals of the astrophyllite group . Mineralogical Magazine , 39 , 97 – 111 . Macdonald R. Upton B.G.J. ( 1993 ) The Proterozoic Gardar rift zone, south Greenland: comparisons...

... of the amphiboles: report of the sub-committee on amphiboles of the International Mineralogical Association, Commission on New Minerals and Mineral Names . Mineralogical Magazine , 61 , 295 – 321 . MacDonald , R. and Upton , B.G.J. ( 1993 ) The Proterozoic Gardar rift zone, south Greenland...

... that have been recycled and re-deposited within the rift. Erosional remnants of pre-Gardar cover sequences that may have acted as intermediate repositories occur in the border zone between the Archaean and Ketilidian provinces of southern Greenland (Allaart, 1976 ). Trace elements...

... of Motzfeldt magmatism. We suggest that rocks previously believed to comprise the Motzfeldt centre represent the products of multiple phases of magmatism from Early- to Mid-Gardar times. The ‘Gardar Province’ is the name given to the products of alkaline magmatism associated with continental rifting...

... the asthenospheric mantle and being ‘frozen in’ as metasomites, which were then rapidly remobilized during Gardar rifting. These findings agree with the conclusions of Goodenough et al. (2002) that the lithospheric boundary between the Border Zone of Archaean craton and Proterozoic Ketilidian mobile belt played...

... and geophysics of the East African rift system in Kenya. Professor King summarized the geology in and around the non-volcanic Baikal rift. Dr Upton presented the fascinating story of the intense faulting and associated magmatism of the late Precambrian Gardar province of South Greenland whereas Dr Howell Francis...

... rift margin of western Laurentia: Implications for mineral deposit settings : Geosphere , v. 4 , p. 429 – 444 , doi: 10.1130/GES00121.1 . Macdonald , R. , and Upton , B.G.J. , 1993 , The Proterozoic Gardar rift zone, South Greenland: Comparisons with the East African rift system...

...Tom Andersen Abstract The Mesoproterozoic Qassiarsuk complex in the Gardar Rift in southwestern Greenland comprises lavas, pyroclastic rocks and subvolcanic intrusions of alkaline silicate rocks and carbonatites. The volcanic rocks are interlayered with sandstones and basalts belonging to the lower...

... rift zones ( Wilson 1989 ). There is evidence of zonation within this bed. The lower margin shows definite flow textures with chaotic assemblages of granoblastic quartz clasts, whereas the main body is crumbly and altered and contains relict amygdales, with blocks of remnant unaltered rock...

...R. Halama; T. Wenzel; B. G. J. Upton; W. Siebel; G. Markl Abstract Basalts from the volcano-sedimentary Eriksfjord Formation (Gardar Province, South Greenland) were erupted at around 1.2 Ga into rift-related graben structures. The basalts have compositions transitional between tholeiite...

... & GARDAR RIFTS 377 DSDP 552A 0 m 15 16 17 18 19 20 40 96 6,O 80 1 BRUNHES 100 total CaC03 % coarse CaC03% fine CaC03% DSDP 611 8? BRUN' MAT JARAMILLO EVENT 31 0 Fig. 3. Variations of total carbonate, coarse and fine carbonate fraction at sites 552A and 611. Total carbonate percentages were determined...

..., 2017 ). Rifting at 1.3 Ga formed the Gardar Province (ca. 1.32–1.14 Ga; Upton, 2013 ), which began by deposition of a 3–3.5-km-thick interbedded sequence of rift-related sedimentary-volcanic rocks (the Eriksfjord Group) onto the basement (1.3 Ga; Piper et al., 1999 ). Regional northeast-southwest...

... deposited in the rift valleys and large volumes of alkaline magmas were emplaced in the rifted zones, where they formed dyke swarms and large intrusive complexes ( Emeleus & Upton 1976 ; Upton & Emeleus 1987 ). The Gardar dykes are alkali basaltic to trachytic and phonolitic and also include...