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Showing 1 to 20 of 35 for “"East African Rift"”.
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Thermal and mechanical development of the East African Rift System
… flanks, and volcanoes of the Western and Kenya rift systems have developed along the western and eastern margins of the 1300 km-wide East African plateau. Structural patterns deduced from field, Landsat, and geophysical studies in the Western rift reveal a series of asymmetric basins bounded by …
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Thermal and mechanical development of the East African Rift System
… flanks, and volcanoes of the Western and Kenya rift systems have developed along the western and eastern margins of the 1300 km-wide East African plateau. Structural patterns deduced from field, Landsat, and geophysical studies in the Western rift reveal a series of asymmetric basins bounded by …
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Investigating volcano tectonic interactions in the Natron Rift of the East African Rift System
Continental rifting, like other plate tectonic processes, plays a large role in shaping the Earth's crust. Active rift zones evolve from repeated tectonic and magmatic events including volcanic activity. Through investigations of currently and previously active rifts, scientists have discovered …
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The geochemistry of fluid processes in the eastern branch of the East African Rift System
The East African Rift System is the world's major continental rift. While much geophysical and petrological attention has been paid to it, at least in the eastern branch ("Eastern Rift"), comparatively little research has been carried out into the geochemistry of rift fluids, despite the potential …
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Tracing mantle degassing along the East African Rift using He and C isotopes: a geospatial approach
… as tracers to detect mantle-degassing across the East African Rift. From the literature, a database of R/Ra and δ13C-CO2 values was produced with accompanying isotopic and geochemical data. The data was filtered, removing samples of ambiguous origin, and samples heavily altered by secondary …
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A Geodynamic Investigation of Continental Rifting and Mantle Rheology: Madagascar and East African Rift case studies
Continental rifting is an important geodynamic process during which the Earth's outer-most rigid shell undergoes continuous stretching resulting in continental break-up and theformation of new oceanic basins. The East African Rift System, which has two continentalsegments comprising largely of the …
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EVOLUTION OF FRESHWATER CRABS IN LAKE MALAWI AND THE LAKE MALAWI BASIN IN THE EAST AFRICAN RIFT VALLEY
<p>Lake Malawi is the southernmost lake in the East African Rift Valley and is home to a single species of freshwater crab, the Malawi Blue Crab. Little is known about species diversity and the phylogenetic relationships of the freshwater crabs of Lake Malawi, in contrast to the lake’s …
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Assessing the dynamics of soil erosion and sediment transport under increasing land use pressures in East African Rift Catchments
… change, soil erosion and sediment transport in East African Rift Catchments. This contribution forms a blueprint for future studies using sediment tracing, radionuclide dating, Bayesian Mixing Models and soil erosion mapping, and their reciprocal integration in this challenging environment. An …
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Investigating the Kinematics and Dynamics of Strain Localization in the Northern Western Branch of the East African Rift System
Continental rifts are thought to be formed by repeated episodes of magmatism, reactivation of pre-existing structures, or a combination of both. Continental rifts are evidence of a divergent plate boundary, where tectonic plates are breaking apart. The northern Western Branch of the East African …
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Seismic Studies of the East African Rift System and the Tibetan Plateau: Implications for the Rheology of Lithosphere and the Evolution of Rifts in Continents
Additional evidence for this conclusion comes from my study of eleven intracontinental earthquakes, with magnitudes ranging from 4.9 to 6, which occurred in the mantle beneath the western Himalayan syntaxis, the western Kunlun Mountains, and southern Tibet (near Xigaze). High-resolution seismic …
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Exhumation, rift-flank uplift, and the thermal evolution of the Rwenzori Mountains determined by combined (U-Th)/He and U-Pb thermochronometry
… represent an extreme example of basement rift-flank uplift in the western branch of the East African Rift, a phenomenon common throughout the East African Rift System and characteristic of continental rift systems in general. A thermochronologic study combining (U-Th)/He and U-Pb analysis …
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Lake Magadi and the Soda Lake cycle: a study of the modern sodium carbonates and of Late Pleistocene and Holocene lacustrine core sediments
<p>The Magadi Basin, Kenya, within the East African Rift Valley, contains two closed-basin alkaline lakes, Lake Magadi and Nasikie Engida that now precipitate trona (Na2CO3.NaHCO3.2H2O) and nahcolite (NaHCO3). Observations of the conditions of modern trona and nahcolite deposition in the Magadi …
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East African climate variability on different time scales : the Suguta Valley in the African-Asian Monsoon Domain
Motivation | Societal and economic needs of East Africa rely entirely on the availability of water, which is governed by the regular onset and retreat of the rainy seasons. Fluctuations in the amounts of rainfall has tremendous impact causing widespread famine, disease outbreaks and human …
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Magma genesis beneath active continental rifts
<p>The East African Rift System (EARS) and the West Antarctic Rift System (WARS) are two of the largest continental rift systems on Earth, but the processes governing rift dynamics remain controversial. The large volume and distinct chemistry of Cenozoic rift-related lavas, combined with …
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Layered crustal and mantle structure and anisotropy beneath the Afar Depression and Malawi Rift Zone
… been acquired within the vicinity of continental rift zones, the mechanisms responsible for the breakup of stable continental lithosphere are ambiguous. Eastern Africa is host to the largest contemporary rift zone on Earth, and is thus the most prominent site with which to investigate the …
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Genetic variation in fast-evolving East African cichlid fishes: an evolutionary perspective
Cichlid fishes from the East African Rift lakes Victoria, Tanganyika and Malawi represent a preeminent example of replicated and rapid evolutionary radiation. In this single natural system, numerous morphological (eg. jaw and tooth shape, color patterns, visual sensitivity), behavioral (eg. …
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Petrology and alteration in the core of the Bear Lodge Tertiary intrusive complex, Bear Lodge Mountains, Crook County, Wyoming
… Compared with other Tertiary rocks in northeast Wyoming) the alkali trachyte has anomalously low Na2O/K2O ratios. Chemical changes resulting from alteration of the trachyte include increased K2O and FeO + Fe2O3 , and decreased Na2O, CaO, and MgO. Variation in SiO2 is a reflection of the …
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Etude des risques naturels liés aux interactions entre les mouvements de masse et le réseau hydrographique dans la région des lacs Kivu et Tanganyika
… regions’). The study area belongs to the East African Rift Valley. It is also located in a typically tropical climatic environment. Thus, it is regularly affected by landslides and recurring floods. Flood and landslide issues are often analysed separately while there are many cases of …
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Towards a Pangenome Perspective on the Lake Malawi Cichlid Radiation
The cichlid fishes in the East African Rift lakes are one of nature’s most spectacular vertebrate radiations and form an excellent system to study the evolutionary process of speciation. Lake Victoria, Malawi and Tanganyika are each home to hundreds of species with a wide spectrum of sizes, …
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