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Journal articles on the topic 'Tanzania Craton'

Author: Grafiati

Published: 6 September 2023

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1

Dawson, J. B. "Neogene–Recent rifting and volcanism in northern Tanzania: relevance for comparisons between the Gardar province and the East African Rift valley." Mineralogical Magazine 61, no. 407 (August 1997): 543–48. http://dx.doi.org/10.1180/minmag.1997.061.407.06.

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AbstractThe tectonic position of the intraplate, alkaline volcanic province of N. Tanzania in a broad rift-controlled area astride the boundary between the Tanzania Craton and the circum-cratonic Mozambique Fold Belt, strongly resembles that of the Gardar province of S. Greenland. Earlier-identified petrological analogies between Gardar magmatism and that in the Kenya sector of the East African Rift Valley can be extended to volcanism in N. Tanzania, and analogies specifically with the Gardar agpaitic suite are strengthened by the occurrence of eudialyte and aenigmatite in some Tanzanian peralkaline, silicic volcanics.

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2

Dawson, J. B. "Quaternary kimberlitic volcanism on the Tanzania Craton." Contributions to Mineralogy and Petrology 116, no. 4 (May 1994): 473–85. http://dx.doi.org/10.1007/bf00310913.

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3

Nyblade, Andrew A., Charles A. Langston, Robert J. Last, Christopher Birt, and Thomas J. Owens. "Seismic experiment reveals rifting of craton in Tanzania." Eos, Transactions American Geophysical Union 77, no. 51 (1996): 517. http://dx.doi.org/10.1029/96eo00339.

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4

Doucet, Luc S., Yongjiang Xu, Delphine Klaessens, Hejiu Hui, Dmitri A. Ionov, and Nadine Mattielli. "Decoupled water and iron enrichments in the cratonic mantle: A study on peridotite xenoliths from Tok, SE Siberian Craton." American Mineralogist 105, no. 6 (June 1, 2020): 803–19. http://dx.doi.org/10.2138/am-2020-7316.

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Abstract Water and iron are believed to be key constituents controlling the strength and density of the lithosphere and, therefore, play a crucial role in the long-term stability of cratons. On the other hand, metasomatism can modify the water and iron abundances in the mantle and possibly triggers thermo-mechanical erosion of cratonic keels. Whether local or large scale processes control water distribution in cratonic mantle remains unclear, calling for further investigation. Spinel peridotite xenoliths in alkali basalts of the Cenozoic Tok volcanic field sampled the lithospheric mantle beneath the southeastern margin of the Siberian Craton. The absence of garnet-bearing peridotite among the xenoliths, together with voluminous eruptions of basaltic magma, suggests that the craton margin, in contrast to the central part, lost its deep keel. The Tok peridotites experienced extensive and complex metasomatic reworking by evolved, Ca-Fe-rich liquids that transformed refractory harzburgite to lherzolite and wehrlite. We used polarized Fourier transform infrared spectroscopy (FTIR) to obtain water content in olivine, orthopyroxene (Opx), and clinopyroxene (Cpx) of 14 Tok xenoliths. Olivine, with a water content of 0–3 ppm H2O, was severely degassed, probably during emplacement and cooling of the host lava flow. Orthopyroxene (49–106 ppm H2O) and clinopyroxene (97–300 ppm H2O) are in equilibrium. The cores of the pyroxene grains, unlike olivine, experienced no water loss due to dehydration or addition attributable to interaction with the host magma. The water contents of Opx and Cpx are similar to those from the Kaapvaal, Tanzania, and North China cratons, but the Tok Opx has less water than previously studied Opx from the central Siberian craton (Udachnaya, 28–301 ppm; average 138 ppm). Melting models suggest that the water contents of Tok peridotites are higher than in melting residues, and argue for a post-melting (metasomatic) origin. Moreover, the water contents in Opx and Cpx of Tok peridotites are decoupled from iron enrichments or other indicators of melt metasomatism (e.g., CaO and P2O5). Such decoupling is not seen in the Udachnaya and Kaapvaal peridotites but is similar to observations on Tanzanian peridotites. Our data suggest that iron enrichments in the southeastern Siberian craton mantle preceded water enrichment. Pervasive and large-scale, iron enrichment in the lithospheric mantle may strongly increase its density and initiate a thermo-magmatic erosion. By contrast, the distribution of water in xenoliths is relatively “recent” and was controlled by local metasomatic processes that operate shortly before the volcanic eruption. Hence, water abundances in minerals of Tok mantle xenoliths appear to represent a snapshot of water in the vicinity of the xenolith source regions.

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5

Sanislav, I. V., P. H. G. M. Dirks, T. Blenkinsop, and S. L. Kolling. "The tectonic history of a crustal-scale shear zone in the Tanzania Craton from the Geita Greenstone Belt, NW-Tanzania Craton." Precambrian Research 310 (June 2018): 1–16. http://dx.doi.org/10.1016/j.precamres.2018.02.025.

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6

Asefa, Jima, and Atalay Ayele. "Complex tectonic deformation in Circum-Tanzania Craton: East African Rift System." Journal of African Earth Sciences 170 (October 2020): 103893. http://dx.doi.org/10.1016/j.jafrearsci.2020.103893.

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7

Manya, S., and M. A. H. Maboko. "Dating basaltic volcanism in the Neoarchaean Sukumaland Greenstone Belt of the Tanzania Craton using the Sm–Nd method: implications for the geological evolution of the Tanzania Craton." Precambrian Research 121, no. 1-2 (February 2003): 35–45. http://dx.doi.org/10.1016/s0301-9268(02)00195-x.

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8

RING, UWE, HILDE L. SCHWARTZ, TIMOTHY G. BROMAGE, and CHARLES SANAANE. "Kinematic and sedimentological evolution of the Manyara Rift in northern Tanzania, East Africa." Geological Magazine 142, no. 4 (July 2005): 355–68. http://dx.doi.org/10.1017/s0016756805000841.

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We describe the stratigraphical/sedimentological and structural evolution of the Manyara Rift in the Tanzania Divergence Zone, East Africa. The rift-related Manyara Beds on the shoaling side of the Manyara Rift were deposited between <1.7 and 0.4 Ma and can be separated into a lacustrine lower member and a fluvial upper member. The transition from lacustrine to fluvial sedimentation at ∼ 0.7 Ma appears to be related to a southward shift of major rift faulting. Fault geometry and the kinematics of the faults are consistent with major faulting during NE/E-directed extension. There is also evidence for other extensional directions including radial extension, which might be caused by magmatic activity and/or might reflect oblate strain symmetry where the East African Rift propagated into the Archaean Tanzania Craton and associated termination of rifting caused an increase in the strained area.

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9

Sun, Kai, Lin-lin Zhang, Zhi-dan Zhao, Fu-qing He, Sheng-fei He, Xing-yuan Wu, Lei Qiu, and Xiao-dong Ren. "Episodic crustal growth in the Tanzania Craton: evidence from Nd isotope compositions." China Geology 1, no. 2 (2018): 210–24. http://dx.doi.org/10.31035/cg2018025.

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10

Lawley, Christopher J. M., David Selby, Daniel J. Condon, Matthew Horstwood, Ian Millar, Quentin Crowley, and Jonathan Imber. "Lithogeochemistry, geochronology and geodynamic setting of the Lupa Terrane, Tanzania: Implications for the extent of the Archean Tanzanian Craton." Precambrian Research 231 (July 2013): 174–93. http://dx.doi.org/10.1016/j.precamres.2013.02.012.

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11

Thomas, Robert J., Christopher Spencer, Alphonce M. Bushi, Nick Baglow, Nelson Boniface, Gerrit de Kock, Matthew S. A. Horstwood, et al. "Geochronology of the central Tanzania Craton and its southern and eastern orogenic margins." Precambrian Research 277 (May 2016): 47–67. http://dx.doi.org/10.1016/j.precamres.2016.02.008.

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12

Cook, Y. A., I. V. Sanislav, J. Hammerli, T. G. Blenkinsop, and P. H. G. M. Dirks. "A primitive mantle source for the Neoarchean mafic rocks from the Tanzania Craton." Geoscience Frontiers 7, no. 6 (November 2016): 911–26. http://dx.doi.org/10.1016/j.gsf.2015.11.008.

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13

Manya, Shukrani. "Nd-isotopic mapping of the Archaean–Proterozoic boundary in southwestern Tanzania: Implication for the size of the Archaean Tanzania Craton." Gondwana Research 20, no. 2-3 (September 2011): 325–34. http://dx.doi.org/10.1016/j.gr.2011.01.002.

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14

Macdonald, Ray. "Magmatism of the Kenya Rift Valley: a review." Transactions of the Royal Society of Edinburgh: Earth Sciences 93, no. 3 (September 2002): 239–53. http://dx.doi.org/10.1017/s0263593300000420.

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ABSTRACTTertiary–Recent magmatism in the Kenya Rift Valley was initiated c. 35 Ma, in the northern part of Kenya. Initiation of magmatism then migrated southwards, reaching northern Tanzania by 5–8 Ma. This progression was accompanied by a change in the nature of the lithosphere, from rocks of the Panafrican Mozambique mobile belt through reworked craton margin to rigid, Archaean craton. Magma volumes and the geochemistry of mafic volcanic rocks indicate that magmatism has resulted from the interaction with the lithosphere of melts and/or fluids from one or more mantle plumes. Whilst the plume(s) may have been characterised by an ocean island basalt-type component, the chemical signature of this component has everywhere been heavily overprinted by heterogeneous lithospheric mantle. Primary mafic melts have fractionated over a wide range of crustal pressures to generate suites resulting in trachytic (silica-saturated and-undersaturated) and phonolitic residua. Various Neogene trachytic and phonolitic flood sequences may alternatively have resulted from volatile-induced partial melting of underplated mafic rocks. High-level partial melting has generated peralkaline rhyolites in the south–central rift. Kenyan magmatism may, at some future stage, show an increasing plume signature, perhaps associated ultimately with continental break-up.

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15

Thomas, Robert J., Nick M. W. Roberts, Joachim Jacobs, Alphonce M. Bushi, Matthew S. A. Horstwood, and Abdul Mruma. "Structural and geochronological constraints on the evolution of the eastern margin of the Tanzania Craton in the Mpwapwa area, central Tanzania." Precambrian Research 224 (January 2013): 671–89. http://dx.doi.org/10.1016/j.precamres.2012.11.010.

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16

Brazier, Richard A., Andrew A. Nyblade, Charles A. Langston, and Thomas J. Owens. "Pn wave velocities beneath the Tanzania Craton and adjacent rifted mobile belts, east Africa." Geophysical Research Letters 27, no. 16 (August 15, 2000): 2365–68. http://dx.doi.org/10.1029/2000gl011586.

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17

Sommer, Holger. "“Wet” low angle subduction: a possible mechanism below the Tanzania craton 2 Ga ago." Mineralogy and Petrology 96, no. 1-2 (March 3, 2009): 113–20. http://dx.doi.org/10.1007/s00710-009-0048-3.

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18

Kasanzu, Charles H. "Apatite fission track and (U-Th)/He thermochronology from the Archean Tanzania Craton: Contributions to cooling histories of Tanzanian basement rocks." Geoscience Frontiers 8, no. 5 (September 2017): 999–1007. http://dx.doi.org/10.1016/j.gsf.2016.09.007.

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19

Lemenkova, P. "Tanzania Craton, Serengeti Plain and Eastern Rift Valley: mapping of geospatial data by scripting techniques." Estonian Journal of Earth Sciences 71, no. 2 (2022): 61. http://dx.doi.org/10.3176/earth.2022.05.

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20

Dunn, Stephan C., and Bjorn P. von der Heyden. "Proterozoic – Paleozoic orogenic gold mineralization along the southwestern margin of the Tanzania Craton: A review." Journal of African Earth Sciences 185 (January 2022): 104400. http://dx.doi.org/10.1016/j.jafrearsci.2021.104400.

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21

Boniface, Nelson, and Volker Schenk. "Neoproterozoic eclogites in the Paleoproterozoic Ubendian Belt of Tanzania: Evidence for a Pan-African suture between the Bangweulu Block and the Tanzania Craton." Precambrian Research 208-211 (July 2012): 72–89. http://dx.doi.org/10.1016/j.precamres.2012.03.014.

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22

Tiberi, C., S. Gautier, C. Ebinger, S. Roecker, M. Plasman, J. Albaric, J. Déverchère, et al. "Lithospheric modification by extension and magmatism at the craton-orogenic boundary: North Tanzania Divergence, East Africa." Geophysical Journal International 216, no. 3 (December 10, 2018): 1693–710. http://dx.doi.org/10.1093/gji/ggy521.

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23

Caracciolo, L., S. Andò, P. Vermeesch, E. Garzanti, R. McCabe, M. Barbarano, C. Paleari, M. Rittner, and T. Pearce. "A multidisciplinary approach for the quantitative provenance analysis of siltstone: Mesozoic Mandawa Basin, southeastern Tanzania." Geological Society, London, Special Publications 484, no. 1 (February 27, 2019): 275–93. http://dx.doi.org/10.1144/sp484-2018-136.

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AbstractThis paper shows how heavy minerals and single-grain varietal studies can be conducted on silt (representing c. 50% of world's sediments) sediments to obtain quantitative data as efficiently as for sand-sized sediments. The analytical workflows include heavy mineral separation using a wide grain-size window (15–355 μ) analysed through integrated optical analysis, Raman spectroscopy, QEMSCAN microscopy and U–Pb dating of detrital zircon. Upper Jurassic–Cretaceous silt-sized sediments from the Mandawa Basin of central-southern Tanzania have been selected for the scope of this research. Raman-aided heavy mineral analysis reveals garnet and apatite to be the most common minerals together with durable zircon, tourmaline and subordinate rutile. Accessory but diagnostic phases are titanite, staurolite, epidote and monazite. Etch pits on garnet and cockscomb features on staurolite document the significant effect of diagenesis on the pristine heavy mineral assemblage. Multivariate statistical analysis highlights a close association among durable minerals (zircon, tourmaline and rutile, ZTR) while garnet and apatite plot alone reflecting independence between the three groups of variables with garnet increasing in Jurassic samples. Raman data for garnet end-member analysis document different associations between Jurassic (richer in A, Bi and Bii types) and Cretaceous (dominant A, Ci and Cii types) samples. U–Pb dating of detrital zircon and their statistical integration with the above-mentioned datasets provide further insights into changes in provenance and/or drainage systems. Metamorphic rocks of the early and late Pan-African orogeny terranes of the Mozambique Belt and those of the Irumide Belt acted as main source of sediment during the Jurassic. Cretaceous sediments record a broadening of the drainage system reaching as far as the Usagran–Ubendian Belt and the Tanzanian Archean Craton.

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24

Bonavia, F. F., and J. Chorowicz. "Northward expulsion of the Pan-African of northeast Africa guided by a reentrant zone of the Tanzania craton." Geology 20, no. 11 (1992): 1023. http://dx.doi.org/10.1130/0091-7613(1992)020<1023:neotpa>2.3.co;2.

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25

Sanislav, Ioan V., Thomas G. Blenkinsop, and Paul H. G. M. Dirks. "Archaean crustal growth through successive partial melting events in an oceanic plateau-like setting in the Tanzania Craton." Terra Nova 30, no. 3 (February 11, 2018): 169–78. http://dx.doi.org/10.1111/ter.12323.

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26

Kabete, J. M., N. J. McNaughton, D. I. Groves, and A. H. Mruma. "Reconnaissance SHRIMP U–Pb zircon geochronology of the Tanzania Craton: Evidence for Neoarchean granitoid–greenstone belts in the Central Tanzania Region and the Southern East African Orogen." Precambrian Research 216-219 (October 2012): 232–66. http://dx.doi.org/10.1016/j.precamres.2012.06.020.

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27

Wölbern, Ingo, Georg Rümpker, Klemens Link, and Forough Sodoudi. "Melt infiltration of the lower lithosphere beneath the Tanzania craton and the Albertine rift inferred from S receiver functions." Geochemistry, Geophysics, Geosystems 13, no. 8 (August 2012): n/a. http://dx.doi.org/10.1029/2012gc004167.

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28

Parisi, Laura, Ian Stanistreet, Jackson Njau, Kathy Schick, Nicholas Toth, and Paul Martin Mai. "Seismological Investigations in the Olduvai Basin and Ngorongoro Volcanic Highlands (Western Flank of the North Tanzanian Divergence)." Seismological Research Letters 91, no. 6 (September 16, 2020): 3286–303. http://dx.doi.org/10.1785/0220200111.

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Abstract We present data and results of a passive seismic experiment that we operated between June 2016 and May 2018 in the Ngorongoro Conservation Area (northern Tanzania), located on the western side of the eastern branch of the Eastern African Rift (EAR) system. The motivation for this experiment is twofold: (1) investigating the extension of the Olduvai basin, referred to also as the “Cradle of Human Mankind,” as it hosted a variety of paleoenvironments exploited by hominins during their evolution; and (2) studying the link between the fault system in the main EAR and in its western flank. We conduct detailed data-quality analysis of the seismic recordings based upon ambient noise characterization and numerical waveform simulations. Our data set is of good quality, and we observe that local magnitude can be overestimated up to at least 0.23, due to wave-amplifications effects occurring at sites with loose sedimentary material. Based on a new but simple approach using power spectral density measurements, we calculate the thickness of sedimentary basins. This allows us to map the bottom of the Olduvai paleolake confirming that its sedimentary record may be at least 200 m deeper than previously inferred from core drilling. We also map the bottom of the Olbalbal depression for the first time. In addition, we present a seismicity map of the Ngorongoro Conservation Area with unprecedented detail. The seismicity depicts the suture zone between the Tanzanian craton and the Mozambique belt and reveals that the fault system in the western flank of the rift merges at depth into a single detachment that joins the Manyara fault on the western side of the main rift valley.

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29

Manya, Shukrani, Katsura Kobayashi, Makenya A. H. Maboko, and Eizo Nakamura. "Ion microprobe zircon U–Pb dating of the late Archaean metavolcanics and associated granites of the Musoma-Mara Greenstone Belt, Northeast Tanzania: Implications for the geological evolution of the Tanzania Craton." Journal of African Earth Sciences 45, no. 3 (July 2006): 355–66. http://dx.doi.org/10.1016/j.jafrearsci.2006.03.004.

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30

Dawson, J. B. "Chapter 4 Geophysical evidence for the structure of the crust and upper mantle of the Tanzania Craton and the Gregory Rift Valley." Geological Society, London, Memoirs 33, no. 1 (2008): 13–20. http://dx.doi.org/10.1144/m33.4.

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31

Clutier, A., S. Gautier, and C. Tiberi. "Hybrid local and teleseismic P-wave tomography in North Tanzania: role of inherited structures and magmatism on continental rifting." Geophysical Journal International 224, no. 3 (November 11, 2020): 1588–606. http://dx.doi.org/10.1093/gji/ggaa538.

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SUMMARY While local earthquake tomography is typically used to image the crust, this technique has restricted depth penetration due to short receiver-source distances. Regional tomography however aims to image the upper mantle from teleseismic events but suffers from poor resolution from 0 down to 40 km depth. We present here a hybrid method that combines the two approaches taking advantage of the short-wavelength resolution within the crust to better constrain the ray path at depth, and thus to improve the lithospheric imaging. Using this new method enhances the continuity or disruption of mantle anomalies towards the surface. Such hybrid tomographic images of crust-to-upper mantle structures are then critical to understand the relation and interplay between the thermal and mechanical lithospheric processes and the role in the localization of the deformation at the surface. We apply our approach to the North Tanzanian Divergence (NTD), where those processes interact with a cold cratonic lithosphere. Our new tomographic images clearly demonstrate the impact of deep-seated processes on surface features. First, strong lateral velocity anomalies and clustered seismicity in the crust are consistent with the surface geology of the NTD (rifted basins, volcanoes and border faults). Then, at a lithospheric scale, the velocity distribution highlights the major role of inherited structures in guiding the rift opening. In particular, our study suggests a strong influence of the Masai cratonic block, south of the NTD, in the rift evolution. The transition from the north–south axial valley into three diverging rift arms (Eyasi, Natron-Manyara and Pangani) is likely due to the change in rheology and to the presence of magma along inherited sutures between the craton and the mobile belts.

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32

Boniface, Nelson. "An overview of the Ediacaran-Cambrian orogenic events at the southern margins of the Tanzania Craton: Implication for the final assembly of Gondwana." Journal of African Earth Sciences 150 (February 2019): 123–30. http://dx.doi.org/10.1016/j.jafrearsci.2018.10.015.

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33

Sanislav, I. V., R. J. Wormald, P. H. G. M. Dirks, T. G. Blenkinsop, L. Salamba, and D. Joseph. "Zircon U–Pb ages and Lu–Hf isotope systematics from late-tectonic granites, Geita Greenstone Belt: Implications for crustal growth of the Tanzania Craton." Precambrian Research 242 (March 2014): 187–204. http://dx.doi.org/10.1016/j.precamres.2013.12.026.

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34

Boniface, Nelson, and Peter Appel. "Neoproterozoic reworking of the Ubendian Belt crust: Implication for an orogenic cycle between the Tanzania Craton and Bangweulu Block during the assembly of Gondwana." Precambrian Research 305 (February 2018): 358–85. http://dx.doi.org/10.1016/j.precamres.2017.12.011.

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35

Mshiu, Elisante Elisaimon, and Makenya A. H. Maboko. "Geochemistry and petrogenesis of the late Archaean high-K granites in the southern Musoma-Mara Greenstone Belt: Their influence in evolution of Archaean Tanzania Craton." Journal of African Earth Sciences 66-67 (May 2012): 1–12. http://dx.doi.org/10.1016/j.jafrearsci.2012.03.002.

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36

Gouedji, Franck, Christian Picard, Yacouba Coulibaly, Marc-Antoine Audet, Thierry Auge, Philippe Goncalves, Jean-Louis Paquette, and Naomi Ouattara. "The Samapleu mafic-ultramafic intrusion and its Ni-Cu-PGE mineralization: an Eburnean (2.09 Ga) feeder dyke to the Yacouba layered complex (Man Archean craton, western Ivory Coast)." Bulletin de la Société Géologique de France 185, no. 6 (June 1, 2014): 393–411. http://dx.doi.org/10.2113/gssgfbull.185.6.393.

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Abstract The Yacouba layered complex intrudes the Archean (3.5–2.7 Ga) Kenema-Man craton in the Samapleu-Yorodougou area, western Ivory Coast. In Samapleu area, the complex was recognized in drill holes at three locations: Samapleu Main (SM); Samapleu Extension 1 (E1) and Yorodougou (Yo). It comprises websterites, peridotites and gabbro-norites arranged symmetrically with mafic layers at the center and ultramafic layers at both margins. The complex is inclined at 70–80° to the SE. The thickness of individual layers varies from 2 to 60 m and the total thickness is 120 to 200 m. At the E1 site, the complex extends to depths > 500 m. Contacts with the country rock gneiss are characterized by a hybrid zone that is a few meters thick and composed of plagioclase-orthopyroxene bearing metabasites, and locally (E1 site) a metamorphic assemblage of sapphirine-cordierite-sillimanite-spinel ± rutile. This assemblage is attributed to contact metamorphism during intrusion of the complex in the lower crust at a depth of about 25 km. Zircons in country rock gneisses and granulites, as well as in the hybrid facies, yield Archean ages of ~ 2.78 Ga, similar to ages reported in the Man craton. Rutiles in the hybrid zone give a U-Pb age of 2.09 Ga, which is interpreted as the age of contact metamorphism and emplacement of the intrusion. The Samapleu Main and Samapleu Extension 1 sites contain Ni and Cu sulfide deposit with reserves estimated as more than 40 million tons grading 0.25% Ni and 0.22% Cu (Sama Nickel-CI, August 2013). The Ni-Cu mineralization is composed of pentlandite, chalcopyrite, pyrrhotite and rare pyrite, which is disseminated mainly in pyroxenite or occurs as subvertical and semi-massive to massive sulfide veins. The sulfide textures range from matrix ore, net-textured, droplets or breccia textures. Zones enriched in PGM, particularly Pd, are associated with the sulfides and several chromite bands are also present. These observations suggest that an immiscible sulfide liquid formed from a parental silicate liquid and percolated through the crystal pile. The parental melt composition, determined using the Chai and Naldrett [1992] method, has a SiO2-rich mafic composition with 53% SiO2 and 10% MgO. This result, the presence of the hybrid zone, and the trace-element signature determined using the Bedard [1994] method, suggest a mantle-derived basaltic parental magma that had assimilated abundant continental crust. These observations indicate that Samapleu intrusion corresponds to a magmatic conduit of the Yacouba complex as at Jinchuan (China), Voisey’s bay (Canada), Kabanga (Tanzania) or Nkomati (South Africa).

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37

Kwelwa, S. D., I. V. Sanislav, P. H. G. M. Dirks, T. Blenkinsop, and S. L. Kolling. "Zircon U-Pb ages and Hf isotope data from the Kukuluma Terrain of the Geita Greenstone Belt, Tanzania Craton: Implications for stratigraphy, crustal growth and timing of gold mineralization." Journal of African Earth Sciences 139 (March 2018): 38–54. http://dx.doi.org/10.1016/j.jafrearsci.2017.11.027.

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38

Koegelenberg, C., A. F. M. Kisters, J. D. Kramers, and D. Frei. "U–Pb detrital zircon and 39Ar–40Ar muscovite ages from the eastern parts of the Karagwe-Ankole Belt: Tracking Paleoproterozoic basin formation and Mesoproterozoic crustal amalgamation along the western margin of the Tanzania Craton." Precambrian Research 269 (October 2015): 147–61. http://dx.doi.org/10.1016/j.precamres.2015.08.014.

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39

Fullea, J., S. Lebedev, Z. Martinec, and N. L. Celli. "WINTERC-G: mapping the upper mantle thermochemical heterogeneity from coupled geophysical–petrological inversion of seismic waveforms, heat flow, surface elevation and gravity satellite data." Geophysical Journal International 226, no. 1 (March 10, 2021): 146–91. http://dx.doi.org/10.1093/gji/ggab094.

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SUMMARY We present a new global thermochemical model of the lithosphere and underlying upper mantle constrained by state of the art seismic waveform inversion, satellite gravity (geoid and gravity anomalies and gradiometric measurements from ESA's GOCE mission), surface elevation and heat flow data: WINTERC-G. The model is based upon an integrated geophysical–petrological approach where seismic velocities and density in the mantle are computed within a thermodynamically self-consistent framework, allowing for a direct parametrization in terms of the temperature and composition variables. The complementary sensitivities of the data sets allow us to constrain the geometry of the lithosphere–asthenosphere boundary, to separate thermal and compositional anomalies in the mantle, and to obtain a proxy for dynamic surface topography. At long spatial wavelengths, our model is generally consistent with previous seismic (or seismically derived) global models and earlier integrated studies incorporating surface wave data at lower lateral resolution. At finer scales, the temperature, composition and density distributions in WINTERC-G offer a new state of the art image at a high resolution globally (225 km average interknot spacing). Our model shows that the deepest lithosphere–asthenosphere boundary is associated with cratons and, also, some tectonically active areas (Andes, Persian Gulf). Among cratons we identify considerable differences in temperature and composition. The North American and Siberian Cratons are thick (>260 km) and compositionally refractory, whereas the Sino-Korean, Aldan and Tanzanian Cratons have a thinner, fertile lithosphere, similar to younger continental lithosphere elsewhere. WINTERC-G shows progressive thickening of oceanic lithosphere with age, but with significant regional differences: the lithospheric mantle beneath the Atlantic and Indian Oceans is, on average, colder, more fertile and denser than that beneath the Pacific Ocean. Our results suggest that the composition, temperature and density of the oceanic mantle lithosphere are related to the spreading rate for the rates up to 50–60 mm yr–1: the lower spreading rate, the higher the mantle fertility and density, and the lower the temperature. At greater spreading rates, the relationship disappears. The 1-D radial average of WINTERC-G displays a mantle geothermal gradient of 0.55–0.6 K km–1 and a potential temperature of 1300–1320 °C for depths >200 km. At the top of the mantle transition zone the amplitude of the maximum lateral temperature variations (cratons versus hotspots) is about 120 K. The isostatic residual topography values, a proxy for dynamic topography, are large (>1 km) mostly in active subduction settings. The residual isostatic bathymetry from WINTERC-G is remarkably similar to the pattern independently determined based on oceanic crustal data compilations. The amplitude of the continental residual topography is relatively large and positive (>600 m) in the East European Craton, Greenland, and the Andes and Himalayas. By contrast, central Asia, most of Antarctica, southern South America and, to a lesser extent, central Africa are characterized by negative residual topography values (>–400 m). Our results show that a substantial part of the topography signal previously identified as residual (or dynamic) is accounted for, isostatically, by lithospheric density variations.

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Foley, S. F., K. Link, J. V. Tiberindwa, and E. Barifaijo. "Patterns and origin of igneous activity around the Tanzanian craton." Journal of African Earth Sciences 62, no. 1 (January 2012): 1–18. http://dx.doi.org/10.1016/j.jafrearsci.2011.10.001.

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CLOUTIER, J., R. STEVENSON, and M. BARDOUX. "Nd isotopic, petrologic and geochemical investigation of the Tulawaka East gold deposit, Tanzanian Craton." Precambrian Research 139, no. 3-4 (September 9, 2005): 147–63. http://dx.doi.org/10.1016/j.precamres.2005.06.002.

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Gibson, S. A., S. C. McMahon, J. A. Day, and J. B. Dawson. "Highly Refractory Lithospheric Mantle beneath the Tanzanian Craton: Evidence from Lashaine Pre-metasomatic Garnet-bearing Peridotites." Journal of Petrology 54, no. 8 (May 15, 2013): 1503–46. http://dx.doi.org/10.1093/petrology/egt020.

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Wang, Zhensheng, Timothy M. Kusky, Jianmin Fu, Yuefeng Yuan, and Peimin Zhu. "Review of Lithospheric Destruction in the North China, North Atlantic, and Tanzanian Cratons." Journal of Geology 124, no. 6 (November 2016): 699–721. http://dx.doi.org/10.1086/688608.

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Plasman, Matthieu, Sophie Hautot, Pascal Tarits, Stéphanie Gautier, Christel Tiberi, Bernard Le Gall, Khalfan Mtelela, and Remigius Gama. "Lithospheric Structure of a Transitional Magmatic to Amagmatic Continental Rift System—Insights from Magnetotelluric and Local Tomography Studies in the North Tanzanian Divergence, East African Rift." Geosciences 9, no. 11 (October 29, 2019): 462. http://dx.doi.org/10.3390/geosciences9110462.

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Continental break-up is controlled by several parameters and processes (rheology, inherited structures, magmatism, etc). Their impact, chronology and interactions are still poorly known and debated, particularly when rifting interacts with cratons. In order to better understand the rifting initiation in a cratonic lithosphere, we analysed 22 magnetotelluric (MT) soundings collected along two East-West profiles in two different rift segments of the North Tanzanian Divergence. The North Tanzanian Divergence, where the East African Rift is at its earliest stage, is a remarkable example of the transition between magmatic to amagmatic rifting with two clearly identified segments. Only separated by a hundred kilometers, these segments, Natron (North) and Manyara (South), display contrasted morphological (wide versus narrow), volcanic (many versus a few edifices) and seismic (shallow versus deep activity) signatures. Magnetotelluric profiles across the two segments were inverted with a three-dimensional approach and supplied the resistive structure of the upper lithosphere (down to about 70 km). The Natron segment has a rather conductive lithosphere containing several resistive features (Proterozoic Belt), whereas the Manyara segment displays highly resistive blocks probably of cratonic nature encompassing a conductive structure under the axial valley. The joint interpretation of these models with recent local and regional seismological studies highlights totally different structures and processes involved in the two segments of the North Tanzanian Divergence. We identified contrasted CO2 content, magma upwelling or trapping, in depth regarding the Manyara or the Natron branch and the influence of inherited cratonic structures in the rifting dynamics.

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Bellucci, Jeremy J., William F. McDonough, and Roberta L. Rudnick. "Thermal history and origin of the Tanzanian Craton from Pb isotope thermochronology of feldspars from lower crustal xenoliths." Earth and Planetary Science Letters 301, no. 3-4 (January 2011): 493–501. http://dx.doi.org/10.1016/j.epsl.2010.11.031.

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Gabert, G. "Lithostratigraphic and tectonic setting of gold mineralization in the Archean cratons of Tanzania and Uganda, East Africa." Precambrian Research 46, no. 1-2 (January 1990): 59–69. http://dx.doi.org/10.1016/0301-9268(90)90066-y.

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Chesley, John T., Roberta L. Rudnick, and Cin-Ty Lee. "Re-Os systematics of mantle xenoliths from the East African Rift: age, structure, and history of the Tanzanian craton." Geochimica et Cosmochimica Acta 63, no. 7-8 (April 1999): 1203–17. http://dx.doi.org/10.1016/s0016-7037(99)00004-6.

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Clément, Jean-Philippe, Martial Caroff, Christophe Hémond, Jean-Jacques Tiercelin, Claire Bollinger, Hervé Guillou, and Joseph Cotten. "Pleistocene magmatism in a lithospheric transition area: petrogenesis of alkaline and peralkaline lavas from the BaringoBogoria Basin, central Kenya Rift." Canadian Journal of Earth Sciences 40, no. 9 (September 1, 2003): 1239–57. http://dx.doi.org/10.1139/e03-046.

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New petrological, geochronological, and geochemical data on basalts, mugearites, peralkaline trachytes, and phonolites from the BaringoBogoria Basin, central Kenya Rift, are presented. KAr dating indicates that the volcanic rocks were emplaced between 894 ± 13 and 92 ± 5 ka. 87Sr/86Sr ranges from 0.70304 to 0.70692, 143Nd/144Nd from 0.51237 to 0.51295, 206Pb/204Pb from 18.4 to 19.8, 207Pb/204Pb from 15.46 to 15.70, and 208Pb/204Pb from 38.2 to 40.5. Despite a rather restricted sampling area and a relatively short time span ([Formula: see text]820 ka), the mineralogical and geochemical variations are not consistent with a simple cogenetic link between the lavas. The studied area is located in a transition zone between two different lithospheric domains (Tanzanian Craton and Panafrican Mobile Belt). We propose that the petrological and geochemical variations of the studied lavas are essentially linked to the nature of the underlying lithosphere. Some basaltic products underwent carbonate contamination, possibly within the crust. Trachytes and phonolites are derived from different basaltic parents through crustal assimilation coupled with fractional crystallization. One phonolite sample contains primary calcite-rich veinlets. Textural relations and geochemical evidence suggest that there is a direct cogenetic link between these carbonate and phonolite melts. The veinlets are the modal expression of a carbonate component included in all the phonolites from the BaringoBogoria Basin.

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Fletcher, Andrew W., Mohamed G. Abdelsalam, Luelseged Emishaw, Estella A. Atekwana, Daniel A. Laó‐Dávila, and Ahmed Ismail. "Lithospheric Controls on the Rifting of the Tanzanian Craton at the Eyasi Basin, Eastern Branch of the East African Rift System." Tectonics 37, no. 9 (September 2018): 2818–32. http://dx.doi.org/10.1029/2018tc005065.

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Aulbach, Sonja, Roberta L. Rudnick, and William F. McDonough. "Li-Sr-Nd isotope signatures of the plume and cratonic lithospheric mantle beneath the margin of the rifted Tanzanian craton (Labait)." Contributions to Mineralogy and Petrology 155, no. 1 (July 17, 2007): 79–92. http://dx.doi.org/10.1007/s00410-007-0226-4.

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