The Tarim Geopuzzle in the Neoproterozoic Rodinia Supercontinent: A Synthesis Review

The Neoproterozoic era marks a turning point in Earth history when the formation and breakup of supercontinent Rodinia drastically changed the configuration of plates and life environments. While most large cratons have been well placed within the Rodinia reconstructions through geological and paleomagnetic constraints, the former positions of many smaller micro-continents, such as those across the Asia region, remain poorly understood. Although the Tarim Craton played a vital role in linking the assembly and dispersal of the Rodinia supercontinent, a long-lasting controversy remains regarding the tectonic configuration of the Tarim Craton in the Rodinia mosaic. In this paper we synthesize the Meso- to Neoproterozoic stratigraphy and magmatism of the Tarim Craton and evaluate the current tectonic and paleogeographic models addressing the “Tarim geopuzzle” within Rodinia configuration. The Central Tianshan and Yili blocks are considered part of a Wilson Cycle evolution of the Tarim Craton during this time interval. Key geological features common to both the “ Great Tarim ” and western Laurentia include: 780–760 Ma mafic dike swarms along the northern edge of the Tarim Craton and the 780 Ma Gunbarrel Large Igneous Province; plume-driven continental rifting episode and synchronous basin initiation along conjugate margins; a Mesoproterozoic granitoid belt in Central Tianshan that is comparable to the ∼1.4 Ga Granite–Rhyolite Belt in southern Laurentia; compatible source-to-sink systems in Mesoproterozoic basins; and, coeval ∼650–615 Ma magmatism with rift-to-drift tectonics leading to passive margin development. Several key issues warrant focused investigation in future studies. These include the need to re-evaluate the ambiguous latest Mesoproterozoic Grenville-age orogeny in light of newly available zircon datasets; the nature and geodynamic significance of an Early Neoproterozoic intracontinental rifting event in southern Tarim that may record a two-stage rifting-amalgamation history within the core of Rodinia, involving initial separation from Australia followed by amalgamation with Laurentia; and, the significance of the apparent time lag (several tens of millions of years) between rift-to-drift tectonics and the paleomagnetically inferred Australia–Laurentia breakup. Addressing these issues will be critical for testing alternative paleogeographic reconstructions and for evaluating the viability of placing Tarim or other continental blocks in a core position within the Rodinia supercontinent.