26 research outputs found
Crustal architecture in Northern Mozambique : results from a regional bedrock mapping project [abstract]
Monazite response to ultrahigh-pressure subduction from U–Pb dating by laser ablation split stream
Gahnite composition as a means to fingerprint metamorphosed massive sulfide and non-sulfide zinc deposits
The geology and geochemistry of the East African Orogen in Northeastern Mozambique
The geology of northeastern Mozambique has been remapped at 1:250 000 scale. Proterozoic rocks, which make up the bulk of
the area, form a number of gneiss complexes defined on the basis of their lithologies, metamorphic grade, structures, tectonic
relationships and ages. The gneiss complexes, which contain both ortho- and paragneisses, range from Palaeo- to Neoproterozoic
in age, and were juxtaposed along tectonic contacts during the late Neoproterozoic to Cambrian Pan-African Orogeny. In this paper
we describe the geological evolution of the terranes north of the Lurio Belt, a major tectonic boundary which separates the
complexes described in this paper from the Nampula Complex to the south. The Marrupa, Nairoto and Meluco Complexes are
dominated by orthogneisses of felsic to intermediate compositions. Granulitic rocks, including charnockites, are present in the
Unango, M’Sawize, Xixano and Ocua Complexes (the last forms the centre of the Lurio Belt). The Neoproterozoic Geci and
Txitonga Groups are dominated by metasupracrustal rocks at low metamorphic grades and have been tectonically juxtaposed with
the Unango Complex. Geochemical data integrate and support a model of terrain assembly in northeast Mozambique, which is
largely published and mainly derived from our new geochronological, lithostratigraphic and structural work. This model shows
the contrast between the mainly felsic lower tectonostratigraphic levels (Unango, Marrupa, Nairoto and Meluco Complexes) and
the significantly more juvenile overlying complexes (Xixano, Muaquia, M’Sawize, Lalamo and Montepuez Complexes), which were
all assembled during the Cambrian Pan-African orogeny. The juxtaposed terranes were stitched by several suites of Cambrian
late- to post-tectonic granitoids
Neoproterozoic evolution of Western Ethiopia: igneous geochemistry, isotope systematics and U–Pb ages
The geology of Niassa and Cabo Delgado Provinces with parts of Zambesia and Nampula Provinces, Mozambique. Map Explanations for sheets 1039 Muidine, 1040 Palma, 1134 Ponte Messuli, 1135 Lupilichi, 1136 Milepa, 1137 Macalange, 1138, Negomano, 1139 Mueda, 1140 Moçimboa da Praia, 1234 Metangula, 1235 Macaloge-Chiconono, 1236 Mavago, 1237 Mecula, 1238 Xixano, 1239 Meluco, 1240 Quissinga-Pemba, 1334 Meponda, 1335 Lichinga, 1336 Majune, 1337 Marrupa, 1338 Namuno, 1339 Montepuez, 1340 Mecufi, 1435 Mandimba, 1436 Cuamba, 1437 Malama, 1438 Ribaue-Mecuburi, 1535 Insaca, 1536 Gurué, 1635 Milange, 1636 Lugela-Mocuba.
Understanding object motion: Recognition, learning, and spatiotemporal reasoning
TIB: RN 3437(145) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman
Crustal architecture of the Mozambique belt in Northeastern Mozambique : perspective from U-Pb geochronology and Lu-Hf isotopes in zircon
Mesoproterozoic geology of the Nampula Sub-province, northern Mozambique
The Nampula Subprovince (NSP) of the Mozambique Metamorphic Province covers over 100 000 km2, making it the largest Mesoproterozoic crustal block in northern Mozambique and an important
component of the Neoproterozoic to Cambrian (Pan-African) East African Orogen. It is bounded in the
north by the WSW–ENE trending Lúrio Belt. The oldest rocks (Mocuba Suite) are a polydeformed
sequence of upper amphibolite grade layered grey gneisses and migmatites associated with intrusive
TTG and granitic orthogneisses. A sample of banded gneiss, interpreted as a meta-volcanic rock,
yielded a U-Pb SHRIMP zircon date of 1127 ± 9 Ma. Metamorphic rims, dated at ca. 1090 Ma,
probably grew during the emplacement of a later magmatic phase, represented by the tonalitic Rapale
orthogneiss, two samples of which were dated at 1095 ± 19 and 1091 ± 14 Ma respectively. The
earliest (D1) deformation and associated amphibolite-grade metamorphism and migmatisation
recognised, took place at approximately this time. The geochemistry of these rocks suggests that they
were generated in a juvenile, island-arc setting. The Mocuba Suite is interlayered with extensive belts
of meta-pelitic/psammitic, calc-silicate and felsic to mafic meta-volcanic supracrustal gneisses termed
the Molòcué Group. U-Pb data from detrital zircons from a calc-silicate paragneiss gave a bimodal age
distribution at ca. 1100 and 1800 Ma, showing derivation from rocks of the same age as the Mocuba
Suite and a Palaeoproterozoic source region. The age of the Molòcué Group has been directly
determined by dates of 1092 ± 13 and 1090 ± 22 Ma, obtained from two samples of the leucocratic
(meta-acid volcanic?) Mamala gneiss, one of its major constituent formations. The final phase of
Mesoproterozoic activity is represented by voluminous plutons and sheet-like bodies of foliated
megacrystic granite, augen gneiss and granitic orthogneiss (Culicui Suite) which have A-type granite
geochemical characteristics, and were interpreted to have been generated in a late tectonic,
extensional setting. Three samples from the suite gave identical ages of ca. 1075 Ma. The NSP was
extensively re-worked during the major (D2: Pan-African) collision orogen in Late Neoproterozoic to
Cambrian times, when the major regional fabrics were imposed upon the Mesoproterozoic rocks under
amphibolite grade metamorphic conditions. In the dated samples, this major orogenic event is
represented by metamorphic zircon rims and lower intercept ages of ca 550 to 500 Ma.
The Nampula Subprovince probably made up the NE part of a major Mesoproterozoic mobile belt
which was accreted to the old cratonic nucleus of the Kalahari craton (combined Archaean Kaapvaal-
Zimbabwe-Grunehogna cratons and various Palaeoproterozoic blocks). This mobile belt, fragmented
by Gondwana break-up, consisted of (from west to east) the Namaqua-Natal belt (South Africa), the
Falkland microplate, the Haag Nunatak block (West Antarctica) and the Maudheim (East
Antarctica)(Jacobs et al., 2008). The belt, with a restored length of over 3000 km is a major part of a
worldwide in a system of “Grenvillian” orogens associated with the amalgamation of the
supercontinent of Rodinia (e.g. Li et al., 2008)