Continental crustal growth

Puchtel I. S., Hofmann A. W., Mezger K., Jochum K. P., Shchipansky A. A., and Samsonov A. V. (1998) Oceanic plateau model for continental crustal growth in the Archaean a case study from the Kostomuksha greenstone belt, NW Baltic Shield. Earth Planet. Sci. Lett. 155, 57-74. 

Puchtel I. S., Arndt N. T., Hofmann A. W., Haase K. M., Kroner A., Kulikov V. S., Kulikova V. V., Garbe Schonberg C. D., and Nemchin A. A (1998a) Petrology of mafic lavas within the Onega plateau, central Karelia evidence for 2.0 Ga plume-related continental crustal growth in the Baltic Shield. Contrib. Miner. Petrol. 130, 134-153. 

Holbrook W. S., Lizarralde D., McGeary S., Bangs N., and Diebold J. (1999) Structure and composition of the Aleutian island arc and implications for continental crustal growth. Geology 27, 31-34. 

Rino, S., Komiya, T., Windley, B.F., Katayama, I., Motoki, A., and Hirata, T., 2004. Major episodic increases of continental crustal growth determined from zircon ages of river sands implications for mantle overturns in the early Precambrian. Phys. Earth Planet. Interior, 146, 369-94. 

Common to all crustal growth models is that simple cmstal extraction using the known amount of Early Archean cmst cannot readily account for the degree of depletion evident in some interpretations of the initial and enr compositions of the Archean mantle (Section 2.13.2). In the next sections, the effects of processes other than progressive growth of the continental cmst from a depleting mantle are considered. 

Reymer A. and Schubert G. (1984) Phanerozoic addition rates to the continental crust and crustal growth. Tectonics 3, 63-77. 

Early in the evolution of isotopic studies of ancient crust, Moorbath (1975, 1978) developed the concepts of (i) major Precambrian crustal growth events in which juvenile crust was made, and (ii) the essential indestructibility of continental crust once consolidated by orogenic events. 

Patchett P. J. and Chase C. G. (2002) Role of transform continental margins in major crustal growth episodes. Geology 30, 39—42. 

Patchett P. J. and Gehrels G. E. (1998) Continental influence on Canadian Cordilleran terrains from Nd isotopic study, and significance for crustal growth processes. J. Geol. 106, 269-280. 

Isotopic studies have established that the continental crust is old, in that more than half of it was formed by the end of the Archean. The distinctive igneous components of Archean cratons, coupled with evidence that the crust at this time was overall less mafic, provide clues that crustal growth mechanisms during this period... 

Fig. 3. Some results of previous modelling, (a) Crustal growth scenarios used (curves give crust mass existing at times in the past relative to present-day continental crust mass of 2.1 x lO g (Taylor McLennan 1995). (b) V. Pb/ Pb plot showing modelling...

Sediment subducted to the mantle represents removal of continental crust (i.e., negative crustal growth), an important parameter in models of... 

LIPs associated with the process of continental break-up. What is not yet clear is whether the volcanism associated with continent separation is driving the break-up process or whether the separation process is focusing the volcanism. Nevertheless, the extensive volumes of magma concentrated along volcanic rifted margins cannot be ignored in models of crustal growth. 

An entirely different view of crustal growth, also current for more than 30 years, was espoused by Armstrong (1968) who took seriously the observation that continental crust can be destroyed, recycled, and recreated... 

The age distribution of crustal rocks An estimate of the relative volumes of continental crust of different ages is an obvious way to assess crustal growth models. However, making such an estimate is not straightforward for two reasons. First, it cannot be assumed that the age of the continents is the same at depth as it is at the surface (Corfu, 1987). Second, the reworking of older crust... 

This result could imply that there was an extensive volume of continental crust in existence at 3.5 Ga, strongly supporting the "nogrowth" crustal growth model of Armstrong (1968). However, there are problems with this interpretation. First, because Nb exchange between the crust and mantle is not a simple two-component system (see Section 4.5.1.2.3) and second, because U is mobile in an oxidizing... 

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