The east african rift system comprises a series of connected fault bounded depressions separating the main african nubian plate from the somali plate. All of these tectonic movements have been involved in the formation of the appalachian mountains and the east coast of north america. Holmes, 1951 and the eastwest trending zambeziirumide belts. Relics of the mozambique ocean in the central east african. This epidsode is referred to as the kuunga orogeny following the suggestion of meert et al. A synopsis of events related to the assembly of eastern gondwana pdf.
Pdf the geology and geochemistry of the east african. African orogeny, separate small cratons convergent to form a supercontinent. Pdf the geology and geochemistry of the east african orogen. A comparison within the east african antarctic orogen 3 granulites of northern mozambique northern mozambique is dominated by mesoproterozoic gneisses reworked during the pan african event pinna et al. A first phase of ocean closure and accretion of terranes defines the east african orogeny. The mozambique ocean began closing between madagascarindia and the congotanzania craton between 700 and 580 million years ago, with closure between 600 and 500 million years. Granitic magmatism and granuliteamphibolitegrade metamorphism in the footwall are all associated with formation of the betsileo shear.
Thermochronological history of an orogenpassive margin. Isobaric cooling textures indicate that the meltinfiltrated lower crust cooled slowly and resisted significant exhumation. The book is ideal for any reader interested in unraveling the intricate history of this east africa, and especially for students. The east african orogen eao is a neoproterozoic to early cambrian mobile belt that reflects the collision between india and the african continents. Northern mozambique lies in the core of this major n. First direct evidence of panafrican orogeny associated with. The east african orogeny eao stern, 1994 resulted in formation of hpht granulites in southern kenya, tanzania and northern mozambique meert, 2002, sommer et al. That tectonic evolution was the one that eventually formed the arabian platform. The mozambique belt, extending from east antarctica through east africa up to the arabiannubian shield, formed as a suture between plates during the panafrican orogeny.
Orogens develop while a continental plate is crumpled and thickened to form mountain ranges, and involve a great range of geological processes collectively called orogenesis. African east african orogeny during which several crustal blocks were amalgamated to form the gondwana supercontinent e. The east african orogen stern, 1994 resulted from the amalgamation of arc terranes in the northern arabiannubian shield and continental collision between east african fragments in the south, saharacongotanzaniabangweulu cratons, parts of the azania terrane comprising of madagascar somaliaethiopiaarabia, india, sri lanka. Pan african events culminated in the formation of the late neoproterozoic supercontinent gondwana figure 1. Pan african orogeny an overview sciencedirect topics. This limits the extent to which gravitydriven extensional collapse. The older east african orogeny, manifested in the egcd and the vohibory complex, may be classified as a hot to ultrahot orogen reaching syntectonic temperatures up to c. Opening of the mozambique ocean and formation of rift basins in zambia, malawi, mozambique and sw madagascar was accompanied by emplacement of anorthosite melt in extending crust.
Pdf the east african orogen, extending from southern israel, sinai and jordan in the north to mozambique and madagascar in the south. Pdf the tectonic architecture of central madagascar. Condensed timetable of major geologic events in the east african orogen. Pan african orogeny5 was a complete orogenic cycle and not merely a. It lies at a critical junction between the northsouth trending mozambique belt e. Other articles where panafrican orogeny is discussed. Every orogeny has its own orogenic cycle, but composite orogenesis is common at convergent plate margins. A comparison within the eastafricanantarctic orogen 3 granulites of northern mozambique northern mozambique is dominated by mesoproterozoic gneisses reworked during the panafrican event pinna et al.
Engvik et al pan african granulites of central dronning maud land and mozambique. Now there is an opportunity for anyone to download and read a digest of east african orogenic processes compiled by researchers from several countries along the belt and their colleagues from north america, europe and australia who have been privileged to work in this vast area fritz, h and others 20. One of the structural features left following the panafrican orogeny was an elongate arch extending senw from the tibisti mountains to the vicinity of tripoli, and evidence of this arch is to be found in the separation of the kufrah and murzuq basins, in the brakbin ghanimah uplift. Orogeny simple english wikipedia, the free encyclopedia. For the east african orogen, subdivision of juvenile, cratonic, and reworked. Stern, 1994 is a neoproterozoicearly cambrian mobile belt that today extends south along eastern africa and western arabia. Pan african orogeny in the coastal region of ghana nature. The east african orogeny is the main stage in the neoproterozoic assembly of east and west gondwana along the mozambique belt. The isotopic evolution of the northern east african orogen. We suggest that this highgrade metamorphic event was caused by the collision of fragments of east and west gondwana during the pan african orogeny, associated with ocean closure and the formation. East african and kuunga orogenies in tanzania south. New discoveries in rift basin could reverse the general flow. Engvik et al panafrican granulites of central dronning maud land and mozambique. Evidence from the bulbul shear zone, south ethiopia.
Panafrican events culminated in the formation of the. The east african orogen, extending from southern israel, sinai and jordan in the north to mozambique and madagascar in the south, is the worl d. Shield in the north and the mozambique belt in the south fig. The east african orogeny eao is the main stage in the neoproterozoic assembly of east and west gondwana australiaindiaantarctica and africasouth america along the mozambique belt.
Tectonic evolution and hydrocarbon distribution of basins. East african and kuunga orogenies in tanzania south kenya. East african rift, fault kinematics, stress field, since the late stages of the panafrican orogeny, the evolution of east africa was dominated by the progressive dismembering of the gondwana continent, in a dominantly extensional setting but sometimes interrupted by. Influence of rift superposition on lithospheric response to. For the core of the eastafrican orogeny johnson 2002 presented a foreland basin system in west saudi arabia during the late second cycle. Following the emergence of the ocean, a variety of island arcs. Sep 19, 20 orogen styles in the east african orogen. The east african rift system ears is the foremost modern example of a continental rift zone on earth and has beenpivotal in developing our understanding of the early stages of rifting and continental breakup.
Arc assembly and continental collision in the neoproterozoic. Kenya is a vital hub for product imports and distribution to inland markets. The east african orogen, extending from southern israel, sinai and jordan in the north to mozambique and madagascar in the south, is the world. East africa is a productshort region, requiring imports from indian ocean. The metabasic rocks are interpreted as representing components of an island arc with an associated back. The african continent essentially consists of five ancient precambrian cratonskaapvaal, zimbabwe, tanzania, congo, and west africanthat were formed between about 3. Pdf terrane rotation during the east african orogeny.
Paleomagnetic data are currently too few to provide a rigorous test of this proposal, but the extant data do not conflict. Structure of the eastern margin of the east african orogen. Whereas the southern continuation of the eao into the dronning maud land, east antarctica, was proposed by jacobs et al. It takes place when two tectonic plates come together. The east african orogeny eao is the main stage in the neoproterozoic assembly of east and. Smnd and upb isotopic constraints for crustal evolution. Apr, 2016 granulitefacies metamorphism of the palaeoproterozoic early palaeozoic gneiss domains of ne mozambique, east african orogen a. Jelsma encyclopedia of life support systems eolss the worldwide 1.
Panafrican granulites of central dronning maud land and. Arabia and north east africa figure 2, the damara kaokogariep belt and lufilian arc of southcentral and southwestern africa, the west congo belt of angola and congo republic, the transsahara belt of west africa, and the rokelide and mauretanian belts along the western part of the west african craton figure 1. Phanerozoic orogenicgold deposits are estimated at just over one billion. Influence of rift superposition on lithospheric response. An orogeny is an event that leads to both structural deformation and compositional differentiation of the earths lithosphere crust and uppermost mantle at convergent plate margins. Read structure of the eastern margin of the east african orogen in central madagascar, precambrian research on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. An introductory history documents the transformation of east africa from the stone age to the first decade of the twentyfirst century. The mozambique belt, extending from east antarctica through east africa up to the arabiannubian shield, formed as a suture between plates during the pan african orogeny.
A synopsis of events related to the assembly of eastern. Following the pan african orogeny the kufrah basin shows evidence of extensional tectonics during the infracambrian to early cambrian with the development of pullapart basins formed as a result of shearing along the pannotian suture figure 2. Implication on the evolution of the east african orogeny. Oceans persisted after 620 ma between east antarctica, india, southern parts of the congotanzaniabangweulu cratons and the zimbabwekalahari craton. Rodinia, grenville orogeny, and taconic orogeny a brief geologic history of the appalachians begins with the convergence of protocontinents called cratons into an early supercontinent named rodinia.
Tectonic evolution and hydrocarbon distribution of basins in. Completion of the nappe assembly around 620 ma is defined as the east african orogeny and was related to closure of the mozambique ocean. The regional geology of northeastern brazil and western nigeria primarily consists of igneous and metamorphic rocks related to the brasilianopan african orogeny that occurred 650 to 480 ma. Several authors14 have advocated that in west africa the 500600 m.
A keystone in a changing worldonline proceedings of the 10th isaes, edited by a. Mozambique ocean in the central east african orogen is not known. Figure 1, from its palaeoproterozoic basement along the shore of lake niassa to the indian ocean coastal plain. Don hallett, daniel clarklowes, in petroleum geology of libya second edition, 2016. The main compressional accretionary phase was followed by episodes of extensional. Postamalgamation basins of the ne arabian shield and. The east african rift system comprises a series of individual graben rift valleys that linkup to form the western and eastern branch. It extends for over 3000 km from the afar triple plate junction, through east africa and into mozambique. A laterally extensive, neoproterozoic extensional detachment the betsileo shear zone is recognized in central madagascar separating the itremo sheet consisting of palaeoprotero. Orogens develop while a continental plate is crumpled and thickened to form mountain ranges.
The authors present superb simplified geological maps of each major part of the orogen, a vast array. The tectonic architecture of the east african orogen in central madagascar. Extending3,500 kmfromthe redsea coastof northernethiopia tomozambique,the earsis consideredto. The geological evolution of africa encyclopedia of life. The book is ideal for any reader interested in unraveling the intricate history of this east africa, and especially for students coming to the study of this region for the first time. Pan african orogeny5 was a complete orogenic cycle and not merely a thermal event that caused isotopic changes. East african rift, fault kinematics, stress field, since the late stages of the pan african orogeny, the evolution of east africa was dominated by the progressive dismembering of the gondwana continent, in a dominantly extensional setting but sometimes interrupted by compressional tectonic inversion. We suggest that this highgrade metamorphic event was caused by the collision of fragments of east and west gondwana during the panafrican orogeny, associated with ocean closure and the formation. Late neoproterozoic granulite facies metamorphism in the.
Brazil and eastern antarctica has been interpreted as a network surrounding older cratons figure 1 and es. In summary, an orogeny is an episode of deformation, metamorphism and magmatism at convergent plate margins, during which many geological processes play a role at convergent plate margins. The laramide orogeny is the process that is responsible for the creation of the rocky. Granulitefacies metamorphism of the palaeoproterozoic early palaeozoic gneiss domains of ne mozambique, east african orogen a. Evolution of the east african and related orogens, and the assembly.
The betsileo shear zone facilitated crustalscale extensional collapse of the east african orogeny, and thus represents a previously poorly recognized structural phase in the story of gondwanan amalgamation. Kola peninsula arcs are about 400 ma emplaced during continental collision in norwegian caledonides 300 km away darcs yellow have yielded 2. Africaipanafrican orogeny 7 30 t east africa and madagascar all ages, n 695 figure 7 histogram of radiometric ages for the mozambique belt of east africa and madagascar. An orogen or orogenic belt develops when a continental plate crumples and is pushed upwards to form one or more mountain ranges. Metamorphic events during the formation of the east african orogen. First direct evidence of panafrican orogeny associated. The oldest basins, dating from 650ma, include as much as 8000m sandstone. Middlelater jurassicpresent, breakup of gondwana, african plate separate from other plates. Neoproterozoic extensional detachment in central madagascar. The geopolitics of east africa 10 products hub system longterm potential to reverse current downstream flows. Granulitefacies metamorphism of the palaeoproterozoic. It comprises a collage of individual oceanic domains and continental fragments between the archean saharacongokalahari cratons in the west and neoproterozoic india in the east. Panafrican orogeny the university of texas at dallas.