Lithosphere, thermal evolution

Schildgen TF, Hodges KV, Whipple KX, Reiners PW, Pringle MS (2007) Uplift of the Altiplano and Western Cordillera revealed through canyon incision history, Southern Peru. Geology 35 523-537 Schmitz MD, Bowring SA (2003) Constraints on the thermal evolution of continental lithosphere from U-Pb accessory mineral thermochronometry of lower crustal xenoliths, southern Africa. Contrib Mineral Petrol... 

Direct evidence for the compositional effects of partial melt extraction is preserved in samples of upper-mantle lithosphere with a range of ages, including Archean cratonic mantle, Proterozoic subcontinental mantle, and modern oceanic mantle. Samples of upper mantle are collected as xenoliths, peridotites dredged from oceanic fracture zones, and slices of upper mantle tectonically exposed at the surface, and extensive samples exist from both oceanic and continental settings (see Chapters 2.04 and 2.05). Here, data sets are assembled for oceanic and subcontinental mantle lithosphere, and compositional trends are compared to those predicted for partial melt extraction from fertile peridotite in order to deduce the role that melt extraction has played in producing compositional variability in upper-mantle lithosphere, and to place constraints on the thermal evolution of the mantle. 

Figure 23 Mantle potential temperature (°C) versus age (Ga) showing thermal evolution models for the upper mantle. The dashed line is a model for whole-mantle convection, and the solid line shows the trace of maximum upper-mantle temperatures in a model of transient layered convection with periodic mantle overturn (Davies, 1995, 1998). The large circles show estimates for average mantle lithosphere. Lithosphere labels are as in Figure 21.

Stein C. A. and Stein S. (1994a) Comparison of plate and asthenospheric flow models for the thermal evolution of oceanic lithosphere. Geophys. Res. Lett. 21, IIB-IVI. 

Morgan P. (1984) The thermal structure and thermal evolution of the continental lithosphere. Pkys. Chem. Earth 15, 107-193. 

Fig. 5. Thermal evolution of the lithosphere along a cross-section of Africa through 34°E. Arrow shows the location of the plume relative to the northward-moving African plate since 45 Ma. It should be noted that lithosphere cools as y/t south of plume, as we have placed no restriction on maximum thickness of the continental lithosphere. The long-term effect of the plume heating can be crudely estimated, if we assume that a 40 km equivalent thickness of material that is 200 K hotter than normal mantle, and with specific heat 4 x 106 JK m", ponds beneath a craton every 300 Ma. The mantle heat flow is increased by 3.4 mWm, or 20-25% of typical mantle heat flow from cratonal areas (e.g. Jaupart et al. 1998). (b) Thickness of plume material ponded beneath lithosphere 45 Ma after plume onset.

Zhong, S., RitzwoUer, M., Shapiro, N., Landuyt, W., Huang, J., and Wessel, P. (2007) Bathymetry of the Pacific plate and its implications for the thermal evolution of lithosphere and mantle dynamics. Journal of Geophysical Research, 112 B06412, 18 PP doi 10.1029/2006JB004628. 

As discussed in the seminal paper by England and Molnar (1990) paleoelevation reflects the combined chemical and physical state of the lithosphere, including thicknesses, thermal structure and bulk chemistry. Tectonic processes such as lithospheric delamination and growth of mountain ranges through either collisional orogenesis or arc evolution may gradually or abruptly... 

Artemieva I. M. and Mooney W. D. (2001) Thermal thickness and evolution of Precambrian lithosphere a global study. J. Geophys. Res. 106, 16387-16414. 

The biological influence on sulfur in the lithosphere may be more fully appreciated by briefly reviewing geological evolution with reference to sulfide mineralisations as summarised by various authors (Watson, 1973 Lacy, 1975). The postulated early events in the sequence are accretion and separation into core, mantle and crust, accompanied by a decline in the thermal gradient with loss of radioactive heating sources. The early crust was very thin and mantle sulfide readily surfaced to be preserved as the volcanogenic... 

The co-ordinated Kaapvaal Project geochron-ological studies of crustal and mantle xenoliths reveal that both crust and mantle have experienced a multi-stage history, and that a simple view of cratonization as a discrete event is not a viable model for craton formation (Schmitz et al. 1998 Schmitz Bowring 2000 Moser et al. 2001). The lower crust in particular retains a comprehensive record of the tectonothermal evolution of the lithosphere. The study of lower-crustal samples has shown that much of the deep craton experienced a dynamic and protracted history of tectonothermal activity that is temporally associated with events seen in the surface record, including late Archaean magmatism (Ventersdorp) and even Proterozoic deformation (Namaqua-Natal) (Schmitz et al. 1998). Thermal events are... 

Temporal evolution of thermal lithosphere above plume... 

Galushkin YI, Dubinin EP (1991) Evolution of ocean floor relief and thermal field of the lithosphere due to ridge axis jumping. Tichooceanskaya Geologiya 6 123-138, (in Russian)... 

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