Not all supercontinents are created equal: Gondwana-Rodinia case study

Laurentia-Baltica-Amazonia relations during Rodinia assembly

“…This process of Rodinia assembly has important implications for understanding the rock record Spencer et al, 2013) (Cawood and Hawkesworth, 2014;Cawood et al, 2013). In contrast Gondwana, which is inferred to have been assembled largely by one sided subduction (Collins and Pisarevsky, 2005) resulting in thickening, reworking and erosion of ancient cratonic lithosphere and resulted in a positive seawater Sr excursion and a shift of Hf values to more negative values Spencer et al, 2013). The paucity of preserved ancient passive margins associated with Rodinia assembly but their relative abundance in association with Gondwana (Bradley, 2008) is also consistent with two-sided subduction during Rodinia assembly.…”

The zircon archive of continent formation through time

“…This was noted by Roberts (2012), and ascribed by Roberts (2013) to continuous continental growth on the margin of the Columbia supercontinental 'lid'. Another significant feature is the large negative 1Hf trend at 550 Ma that correlates with Gondwana formation and reworking of much older crust (see section on 'Regional isotopic trends'; Spencer et al 2013b). The ability to pick out such evolution trends in the Archaean is hindered partly by data coverage, that is, does the drop in U-Pb crystallization ages around 2.3 Ga reflect tectonic shutdown (Condie et al 2009), an under-representation in the data of actual events (Partin et al 2014) or an artefact of preservation (see section 'Preservation of the geological record')?…”

“…convergent systems surrounding the Pacific Ocean) shift to more primitive compositions after the onset of orogenesis, which is interpreted as the result of formation at the boundary of two large mantle convection cells, and thus enhancing the removal of the subcontinental lithospheric mantle. Spencer et al (2013b) explored these differences in ancient orogenic systems that were associated with supercontinent amalgamation, namely the c. 1.0 Ga Grenville orogeny associated with the formation of Rodinia, and the c. 0.6 Ga Pan-African orogeny involved in Gondwana formation. These authors showed that zircons derived from the Pan African orogenies reveal similar isotopic characteristics to the modern internal orogenic systems (Fig.…”

Four-dimensional context of Earth's supercontinents

“…These data suggest that relatively juvenile crust was preferentially recycled during Rodinia amalgamation (Spencer et al 2013). Such contrasting signatures are interpreted to reflect ocean closure by way of single-sided (Gondwana) v. twosided (Rodinia) subduction zones.…”