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The spatiotemporal interaction of large‐ and regional‐scale upper mantle forces can prevail in collisional settings. To better understand the role of these forces on post‐subduction tectonics, we focus on mantle dynamics in the East Anatolian Plateau, a well‐documented segment of the Arabian‐Eurasian continental collision zone. Specifically, we analyze multiple forces in the upper mantle, which have not been considered in previous studies in this region. To this end, we use a state‐of‐the‐art 3D instantaneous geodynamic model to quantify the dynamics of thermally defined upper mantle structures derived from seismic tomography data. Results reveal a prominent SW‐NE‐oriented mantle flow from the Arabian foreland to the Greater Caucasus–a plumelet–through a lithospheric channel under the East Anatolian Plateau. This plumelet induces localized dynamic topography (∼500 m) around the extensional Lake Van province, favoring NE‐directed compression and westward escape of the Anatolian plate. We suggest that the Lake Van region is an active magma‐rich intraplate rift in the Africa‐Arabia‐Anatolian plume‐rift system. The rift zone was probably initiated by Neotethyan subduction‐related forces and has been reactivated and/or sustained by the plumelet‐induced convective support. Our findings are consistent with numerous observations, including the recent low‐ultralow seismic velocities with a SW‐NE splitting anisotropy pattern, geochemical and petrological studies, and local kinematics showing upper mantle‐induced extensional tectonics in the collisional region. Plain Language Summary: Our goal is to better understand the active deformations of post‐subduction tectonics. To this end, we ran a 3D thermomechanical model of the East Anatolian Plateau, one of the most intriguing segments of the Arabian‐Eurasian continental collision zone. The model integrates seismically defined upper mantle structures and uses an open‐source code (ASPECT). Results reveal the significant role of large‐ and regional‐scale upper mantle forces in the study region. At long wavelengths, we find SW‐NE‐oriented mantle flow and associated dynamic topography. We interpret that such flow—a plumelet (regional upper‐mantle plume migration with neither a significant tail extending to the lower mantle nor a mushroom head reaching the hot spots on the surface)—is linked to the large‐scale mantle flow from the Arabian plate to the Greater Caucasus. At short wavelengths, we find localized dynamic topography and high stress and strain anomalies in the Lake Van zone. We argue that the plumelet, which became more forceful after the removal of the subducted Neotethyan slab, may have generated mantle tractions that contribute to magma‐rich‐intraplate rifting in the Lake Van region. Our results are in good agreement with local kinematics, low‐speed seismic velocities with SW‐NE anisotropy patterns, and geochemical‐petrological studies. Key Points: We present the 3D numerical model and observations related to the Africa‐Arabia‐Anatolian plume‐rift systemOur thermomechanical model provides new insight into the magma‐rich intraplate active rifting in collisional settingsIntegrated analyses from the 3D geodynamic model and observations reveal a SW‐NE‐oriented plumelet and its regional implications [ABSTRACT FROM AUTHOR]

The tectonic configuration of the Caribbean plate is defined by inward‐dipping double subduction at its boundaries with the North American and Cocos plates. This geometry resulted from a Paleogene plate reorganization, which involved the abandonment of an older subduction system, the Great Arc of the Caribbean (GAC), and conversion into a transform margin during Lesser Antilles (LA) arc formation. Previous models suggest that a collision between the GAC and the Bahamas platform along the North American passive margin caused this event. However, geological and geophysical constraints from the Greater Antilles do not show a large‐scale compressional episode that should correspond to such a collision. We propose an alternative model for the evolution of the region where lower mantle penetration of the Farallon slab promotes the onset of subduction at the LA. We integrate tectonic constraints with seismic tomography to analyze the timing and dynamics of the reorganization, showing that the onset of LA subduction corresponds to the timing of Farallon/Cocos slab penetration. With numerical subduction models, we explore whether slab penetration constitutes a dynamically feasible set of mechanisms to initiate subduction in the overriding plate. In our models, when the first slab (Farallon/Cocos) enters the lower mantle, compressive stresses increase at the eastern margin of the upper plate, and a second subduction zone (LA) is initiated. The resulting first‐order slab geometries, timings, and kinematics compare well with plate reconstructions. More generally, similar slab dynamics may provide a mechanism not only for the Caribbean reorganization but also for other tectonic episodes throughout the Americas. Plain Language Summary: The Caribbean tectonic plate is bounded by subduction to the east and west. However, it is unclear how this plate configuration was achieved. Previous models suggest that the North American continental margin entered an ancient Caribbean subduction zone between 66 and 34 Mya, converting the margin to strike‐slip and initiating subduction to the east at the Lesser Antilles. However, the deformation expected for this event is absent at the site of the supposed collision. Considering geological and geophysical constraints across the Caribbean, we instead suggest that mantle processes drove the reorganization. Combining tomographic images of the mantle with plate modeling, we reconstruct subduction below the Caribbean. Then, through numerical mantle convection modeling, we simulate the Caribbean subduction setting at the time of the reorganization. Our results show that when a subducting plate enters the lower, higher viscosity part of the mantle, it affects mantle flow, causing compression in the overriding plate and the potential initiation of a second subduction zone. The timing when the first slab enters the lower mantle and subduction initiates aligns well with our reconstructions and geological constraints in the Caribbean. We hypothesize that a similar process may explain other major deformation episodes throughout the Americas. Key Points: Tectonic constraints conflict with previously proposed collision and escape models for Paleogene Caribbean reorganizationSlab reconstructions and geodynamic models suggest Farallon slab anchoring induced tectonic reorganizationIn this model, lower mantle slab penetration triggers mantle flow, lithospheric compression, and subduction initiation [ABSTRACT FROM AUTHOR]

Geochemistry, Geophysics, Geosystems (G‐Cubed) is a respected Earth science journal that publishes research papers, methods, and coding applications. In 2023, the journal received 485 manuscripts and published 244 of them. The journal credits its success to the voluntary contributions of over 764 reviewers who provided more than 937 reviews. The journal expresses gratitude to the reviewers for their time and expertise, as their efforts ensure that the published papers meet the high standards expected by the research community. The journal welcomes feedback on its peer review process and anticipates exciting advancements in the field. Additionally, the document is a list of names of individuals who have contributed to a report or study, organized alphabetically. The purpose of the document is to acknowledge the participation of these individuals, who come from diverse fields, in the research or study. [Extracted from the article]

Key Points: The editors thank the 2022 peer reviewers [ABSTRACT FROM AUTHOR]

Key Point: The editors thank the 2021 peer reviewers [ABSTRACT FROM AUTHOR]

Key Points: The editors thank the 2020 peer reviewers [ABSTRACT FROM AUTHOR]

The publishing process relies on the work of volunteer reviewers, and evaluating the interdisciplinary papers published in G‐Cubed can be challenging. As Editors and Associate Editors, we would like to give our appreciation to all reviewers and would like to acknowledge them in this editorial. G‐Cubed published 326 manuscripts out of 650 submissions in 2019, thanks on the efforts of 860 dedicated reviewers. Their names are listed below, and in italics are those who provided three or more reviews. A big thank you from the G‐Cubed team! Key Point: The editors thank the 2019 peer reviewers [ABSTRACT FROM AUTHOR]

The editorial and scientific publishing process relies on the sustained work of volunteer reviewers, and evaluating the inter‐disciplinary and broad interest papers published in Geochemistry, Geophysics, Geosystems can be a particular challenge. As editors and associated editors, we are therefore hugely appreciative of the efforts of our reviewers, and would like to thank and acknowledge them in this editorial. G‐Cubed published 271 manuscripts in 2018, and for this we were able to rely on the efforts of 873 dedicated reviewers. A big thank you from the G‐Cubed team! Key Points: The editors thank the 2018 peer reviewers [ABSTRACT FROM AUTHOR]

Abstract: Slab‐slab interaction is a characteristic feature of tectonically complex areas. Outward dipping double‐sided subduction is one of these complex cases, which has several examples on Earth, most notably the Molucca Sea and Adriatic Sea. This study focuses on developing a framework for linking plate kinematics and slab interactions in an outward dipping subduction geometry. We used analog and numerical models to better understand the underlying subduction dynamics. Compared to a single subduction model, double‐sided subduction exhibits more time‐dependent and vigorous toroidal flow cells that are elongated (i.e., not circular). Because both the Molucca and Adriatic Sea exhibit an asymmetric subduction configuration, we also examine the role that asymmetry plays in the dynamics of outward dipping double‐sided subduction. We introduce asymmetry in two ways; with variable initial depths for the two slabs (“geometric” asymmetry), and with variable buoyancy within the subducting plate (“mechanical” asymmetry). Relative to the symmetric case, we probe how asymmetry affects the overall slab kinematics, whether asymmetric behavior intensifies or equilibrates as subduction proceeds. While initial geometric asymmetry disappears once the slabs are anchored to the 660 km discontinuity, the mechanical asymmetry can cause more permanent differences between the two subduction zones. In the most extreme case, the partly continental slab stops subducting due to the unequal slab pull force. The results show that the slab‐slab interaction is most effective when the two trenches are closer than 10–8 cm in the laboratory, which is 600–480 km when scaled to the Earth. [ABSTRACT FROM AUTHOR]