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The paper "A dynamic 2000—540 Ma Earth history: From cratonic amalgamation to the age of supercontinent cycle" that was recently published in Earth-Science Reviews by Li et al. (2023) is an impressive piece of work, putting together data for the Proterozoic supercontinent cycle into a coherent model including both maps and animations. Nevertheless, as they write themselves, there will no doubt be room for improvements of their model, some of which I hope to contribute with in this comment from my Baltica perspective, in particular when it comes to the relations between Baltica, Amazonia and West Africa. [ABSTRACT FROM AUTHOR]

Abstract: Sediment provenance analysis remains a powerful method for testing hypotheses on the temporal and spatial evolution of uplifted source regions, but issues such as recycling, nonunique sources, and pre- and post-depositional modifications may complicate interpretation of results from individual provenance techniques. Convergent retroarc systems commonly contain sediment sources that are sufficiently diverse (continental magmatic arc, fold–thrust belt, and stable craton) to enable explicit provenance assessments. In this paper, we combine detrital zircon U–Pb geochronology, heavy mineral identification, Nd isotopic analyses, conventional sandstone petrography, and paleocurrent measurements to reconstruct the clastic provenance history of a long-lived sedimentary basin now exposed in an intermontane zone of the northern Andean hinterland of Colombia. The Middle Magdalena Valley basin, situated between the Central Cordillera and Eastern Cordillera, contains a 5–10km-thick succession of Upper Cretaceous to Quaternary fill. The integrated techniques show a pronounced change in provenance during the Paleocene transition from the lower to upper Lisama Formation. We interpret this as a shift from an eastern cratonic source to a western Andean source composed of magmatic-arc rocks uplifted during initial shortening of the Central Cordillera. The appearance of detrital chloritoid and a shift to more negative εNd(t=0) values in middle Eocene strata of the middle La Paz Formation are attributed to shortening-related exhumation of a continental basement block (La Cira–Infantas paleohigh), now buried, along the axis of the Magdalena Valley. The diverse provenance proxies also show distinct changes during middle to late Eocene deposition of the Esmeraldas Formation that likely reflect initial rock uplift and exhumation of the fold–thrust belt defining the Eastern Cordillera. Upsection, detrital zircon U–Pb ages and heavy mineral assemblages for Oligocene and younger clastic deposits indicate that the Mesozoic sedimentary cover of the Eastern Cordillera was recycled during continued Cenozoic shortening. Our multidisciplinary provenance study refines the tectonic history of the Colombian Andes and demonstrates that uncertainties related to sediment recycling, nonunique sources, source heterogeneity, and climate in interpreting provenance data can be minimized via an integrated approach. [Copyright &y& Elsevier]

The Meso-Neoproterozoic period, sometimes referred to as the 'boring billion' or 'Earth's middle age', spans the interval between the formation of the Columbia and Rodina supercontinents. It is regarded as a stable era of the Earth. However, from a global perspective, there are many intensive events of mafic volcanism, dyke intrusions and formation of rift basins recorded in different cratons during this period. This paper focuses on rift basins that developed in three cratons in China (North China, South China and Tarim cratons), because large-scale primary gasfields, as one of the deep resources, have been discovered recently in rocks of Meso-Neoproterozoic age. The formation mechanisms and tectonic settings of these rift basins as the targets of Deep Earth are discussed, based on the restoration of global positions of the three cratons by pre-existing paleomagnetic data and plate reconstruction. We recognise that the rift basins of the North China Craton are related to extrusion tectonics in the southwest Ordos Block or are pull-apart basins along the northern and southern sides of the Ordos Block. The rift basins of the South China Craton are derived from mantle lithospheric delamination of the Jiangnan Orogen in the eastern South China Craton or subduction retreat and backarc opening in the western South China Craton, respectively. The rift basins of the Tarim Craton originated from the backarc opening along the margin of the Supercontinent Rodinia. [ABSTRACT FROM AUTHOR]