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Fission track (FT) dating of detrital titanites, zircons and apatites combined with sandstone petrography from rocks of the Rovuma Basin was used to constrain the basin's provenance and its post depositional thermal history. A comparison of metamorphic basement and sedimentary titanite and zircon FT data indicates that erosion was localized along a zone which followed the margin of the Rovuma Basin and was the source for the late Jurassic to Cretaceous sandstones. Time–temperature models of apatite FT data show, that after the deposition, the sandstones were heated up to temperatures of ca. 60–110 °C most likely due to a combination of intensified regional heat flux and burial heating caused by fast sedimentation in a transtensional pull-apart setting and intensified by regionally elevated heat flux. The utter western part of the basin was inverted between ca. 60 and 40 Ma, concordant with the drop in the global eustatic sea level which led to a rearrangement of the source-to-sink system. Some reworked zircons were deposited in the Cenozoic strata in the eastern part of the basin.

The postcollisional tectonic development of northeast Mozambique and subsequent cooling from high-temperature metamorphism is delineated with an extensive new set of U-Pb titanite, 40Ar/39Ar hornblende, and 40Ar/39Ar mica analyses. The complex data suggest a polyphase metamorphic history from the late Neoproterozoic to the Ordovician within the East African–Antarctic Orogen (EAAO), with marked differences between the major constituent blocks. In all the data sets, samples from the basement south of the Lu´ rio Belt show generally younger ages than those from the north, resulting from a late metamorphic event and slow cooling between ca. 520 and 440 Ma. The ages north and south of the Lu´ rio Belt are consistently offset by ca. 30–70 Ma, a difference that is maintained and even appears to increase during cooling from very high temperatures to ca. 350C. Based on the first-order assumption that all the ages are cooling ages, cooling rates in the south are estimated at ca. 7–8C/Ma, while those north of the Lu´ rio Belt are faster at ca. 16C/Ma. The data are consistent with previous geochronological, petrographic, and field data and suggest a late high-temperature/low-pressure metamorphic event that affected only the basement rocks south of the Lu´ rio Belt and portions of the latter. This late metamorphism and subsequent delayed, slower cooling agree well with a model of elevated heat flow following lithosphere delamination in the southern part of the orogen, which also explains the observed widespread granitoid magmatism, migmatization, and renewed deformation in the southern basement.

Despite the tremendous advances in laser cooling of neutral atoms and positive ions, no negatively charged ion has been directly laser cooled. The negative ion of lanthanum, ${\mathrm{La}}^{--}$, has been proposed as the best candidate for laser cooling of any atomic anion [ and , Phys. Rev. A 81, 032503 (2010)]. Tunable infrared laser photodetachment spectroscopy is used to measure the bound-state structure of ${\mathrm{La}}^{--}$, revealing a spectrum of unprecedented richness with multiple bound-bound electric dipole transitions. The potential laser-cooling transition ($^{3}{F}_{2}^{e}\ensuremath{\rightarrow}^{3}{D}_{1}^{o}$) is identified and its excitation energy is measured. The results confirm that ${\mathrm{La}}^{--}$ is a very promising negative ion for laser-cooling applications.

Lithospheric thickening during protracted Ediacaran supercontinent assembly was dissipated in various ways along the “Pan-African” East African–Antarctic Orogen. In NE Mozambique, late-tectonic extension and plutonism south of the Lurio Belt has been modelled in terms of lithosphere delamination, although rigorous testing of the hypothesis by structural analysis has not yet been undertaken. This study presents the first analyses of late-tectonic structures in both the Mesoproterozoic basement and the Cambrian cover sequences in the Nampula Complex, NE Mozambique, supported by, and integrated with, new geochronological data. Both late compressional and extensional fabrics overprint the main Pan-African collisional structures to a variable degree in identified structural domains. The long-lived northern boundary of the Nampula Complex, the Lurio Belt high-strain zone, initiated in the Ediacaran, was reactivated and segmented during these later phases, with boundary-parallel shortening. U–Pb SIMS ages from selected latest-tectonic units in the Nampula Complex and the Lurio Belt give consistent ages between 518 ± 2 and 514 ± 5 Ma. They are coeval with migmatisation and granitoid plutonism in the Nampula Complex. U–Pb titanite (471 ± 9 Ma) and 40 Ar/ 39 Ar biotite (431 ± 3 Ma) data suggest subsequent slow cooling rates in the Nampula Complex, consistent with basal heating by asthenosphere uprise following lithosphere delamination. Consequently, we believe the new data suggest that the observed intense late polyphase deformation has preferentially occurred where the delaminated lithosphere was doubly weakened by loss of the mantle root and the resulting long-lived elevated temperature regime.

[1] In this paper, we present a conceptual model to describe the post-Pan-African (