 | Stoppa, F., Woolley, A. R., Lloyd, F. E., Eby, N. (2000) Carbonatite lapilli-bearing tuff and a dolomite carbonatite bomb from Murumuli crater, Katwe volcanic field, Uganda. Mineralogical Magazine, 64 (4) 641-650 doi:10.1180/002646100549661 | Journal (article/letter/editorial) | | dolomite carbonatite bomb from Murumuli crater, Katwe volcanic field, Uganda F. STOPPA1,*, A. R. WOOLLEY2...are described from the Murumuli crater, Katwe-Kikorongo volcanic field, SW Uganda which contain abundant...lapilli contain microphenocrysts of Ti-magnetite, perovskite, apatite, clinopyroxene, sanidine and altered...Carbonatite clearly played an important role in the Katwe-Kikorongo magmatism and it is suggested that carbonatite...carbonatebearing melilitite. K EY WORDS : Katwe-Kikorongo, Uganda, carbonatite lapilli, carbonatite bomb |  | | Journal (article/letter/editorial) | | K-ma®c-carbonatite effusive magmatic association of Katwe-Kikorongo, SW Uganda F. E. Lloyd1;2 , A. R. Woolley3, F. Stoppa4...mica in clinopyroxenite xenoliths and mica in Katwe-Kikorongo mixed melilitite-carbonatite tephra. Higher...high Cr. It is suggested that the genesis of Katwe-Kikorongo olivine melilitite and Fort Portal carbonatite...carbonatite magmatism (Bailey, 1993). The Katwe-Kikorongo volcanic ®eld forms part of the Quaternary to Recent...kamafugite-carbonatite province of south west Uganda in the western branch of the East African Rift (Fig. 1) |  | | Journal (article/letter/editorial) | | composition and carbonate–silicate equilibria in the volcanic rocks of kamafugitic affinity in the Toro-Ankole...from ugandite and mafurite of the Bunyaruguru volcanic field. The initial compositions of melt inclusions...high-Mg ultrapotassic and carbonatite rocks in the western branch of the East African Rift Zone suggests the...area is expressed in the extreme enrichment of volcanic rocks in incompatible elements and mineral composition...crystalline inclusions. In the Fort Portal volcanic field with separate carbonatite volcanoes, carbonatite |  | Bailey, Ken, Lloyd, Felicity, Kearns, Stuart, Stoppa, Francesco, Eby, Nelson, Woolley, Alan (2005) Melilitite at Fort Portal, Uganda: Another dimension to the carbonate volcanism. Lithos, 85 (1) 15-25 doi:10.1016/j.lithos.2005.03.019 | Journal (article/letter/editorial) | | elsevier.com/locate/lithos Melilitite at Fort Portal, Uganda: Another dimension to the carbonate volcanism Ken...ultramafic-carbonate volcanism to the south, in Uganda, and parallels with that in Italy. D 2005 Elsevier...Quaternary volcanic field at the northern end of the Western Rift igneous province in Uganda (Holmes and...tuffs (the major deposit, defining the Fort Portal field); and the lava flows (the smallest eruptive unit)...cones. Although during the 1980Vs, the Fort Portal volcanic rocks were mooted as being calcified natrocarbonatite |  | | Journal (article/letter/editorial) | | Geochemistry and petrogenesis of the Fort Portal, Uganda, extrusive carbonatite G. Nelson Eby a,⁎, Felicity...Quaternary Fort Portal volcanic field occurs at the northern end of the Western Rift in Uganda. The eruptive phases...Portal volcanic field, is the subject of this paper. The Quaternary Fort Portal and Kasekere volcanic fields...fields of southwest Uganda (Fig. 1) were first mapped and described by von Knorring and Du Bois (1961). The...west and north by rift faults associated with the western branch of the East African rift system. Fort Portal |  | | Journal (article/letter/editorial) | | Accepted Manuscript Xenoliths from Bunyaruguru volcanic field: some insights into lithology of East African...Muravyeva, V.G. Senin , Xenoliths from Bunyaruguru volcanic field: some insights into lithology of East African... ACCEPTED MANUSCRIPT Xenoliths from Bunyaruguru volcanic field: some insights into lithology of East African...xenoliths from kamafugites of the Bunyaruguru volcanic field has been determined. The major and some trace...clinopyroxene, phlogopite, Crspinel, titanomagnetite, perovskite and carbonates of xenoliths and their host lavas |  | | Journal (article/letter/editorial) | | are seen. Checks on similar rocks from Germany, Uganda and Tanzania reveal magnetites with comparable...from alkaline and alkaline ultramafic silicate volcanic rocks cover only parts of this array. Magnetite...in the literature, fall in the same composition field, suggesting that this form of carbonatite may be...magnetite did not figure in the cognate assemblage. Volcanic calciocarbonatites were known to contain magnetite...(Keller, 1989) but the only analysed example, from Uganda (Barker and Nixon, 1989), although high in Ti, |  | | Journal (article/letter/editorial) | | accessory perovskite and ‘plumbopyrochlore’; nyerereite is present as inclusions in the perovskite. At least... 1972; King et al., 1972; Woolley, 2001). The volcanic rocks from Tinderet range from 19.9 to 5.5 Ma...Roberts (1984) who identified both plutonic and volcanic carbonatites in the Koru, Songhor and Kipsesin-Ngeron...areas. Deans and Roberts (1984) suggested that the volcanic calcite carbonatites at Tinderet were originally...mineralogical and isotopic data on the Tinderet volcanic carbonatites are presented herein and compared |  | Rosenthal, A., Foley, S.F., Pearson, D.G., Nowell, G.M., Tappe, S. (2009) Petrogenesis of strongly alkaline primitive volcanic rocks at the propagating tip of the western branch of the East African Rift. Earth and Planetary Science Letters, 284 (1) 236-248 doi:10.1016/j.epsl.2009.04.036 | Journal (article/letter/editorial) | | strongly alkaline primitive volcanic rocks at the propagating tip of the western branch of the East African...characteristic of the Toro-Ankole volcanic field in southwestern Uganda, forming the youngest and most northward...northward volcanics of the western branch of the East African Rift. Lavas contain exceptionally low SiO2...Particularly in low magma volume rifts such as the western branch of the East African Rift, silicaundersaturated...a continental rift: it consists of eastern and western branches that have contrasting alkaline chemistry |  | | Journal (article/letter/editorial) | | Stoppa et al. / Lithos 85 (2005) 26–47 27 and field observation. Another, is that the two thirds of...genesis. They are young, fresh, have well-exposed field relationships and are now well-studied. Direct ascent...42° 13° Pleistocene HK-volcanics of the Roman Region Plio-Pleistocene grabens 14° Normal faults ...Ultra-alkaline Province (IUP) outcrops and the Roman Region (RR). 28 F. Stoppa et al. / Lithos 85 (2005)...with standardised multi-method techniques. 3. Field occurrence and lithology The Italian carbonatites |
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