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As the Earth's primary mode of planetary cooling, the oceanic plate is created at mid-ocean ridges, transported across the planet's surface, and destroyed at subduction zones. The evolution of its buoyancy and rheology during its lifespan maintains the coherence of the plate as a distinct geological entity and controls the localised deformation and vertical material exchange at plate boundaries, which enables the horizontal ocean-plate movements. These motions intimately link the oceanic plate to the overarching overturn of Earth's mantle: The plate forms out of rising mantle material at spreading ridges; it cools the Earth's interior as the cold thermal boundary layer to mantle convection; and its sinking portions drive not only the plate itself but also dominate global flow in the mantle. We scrutinise here the entire life cycle of the oceanic plate, starting with its birth at the mid-ocean ridge, including the thermal, rheological, and chemical conditions of initiation, followed by plate maturation as it ages and cools while crossing the seafloor, and finishing with the dynamics of plate destruction as it retires at the subduction zone to become a deeper part of Earth's convective system. We find that the full range of dynamic behaviour of the oceanic plate, including its forcing and overall framework within Earth's convecting system, is not fully captured by the existing concept of Plate Tectonics, which describes solely the horizontal surface kinematics of all plates. Therefore, we introduce a more specific and at the same time more integral concept named “Ocean-Plate Tectonics” that more specifically describes the dynamic life of the oceanic plate and accounts for the knowledge gained during the past 50 years. This “Ocean-Plate Tectonics” must have emerged on Earth at least 1 Billion years ago, and dominates Earth's dynamics today.

In JGR‐Planets, the peer review process is critical to ensuring that the published articles are based on sound scientific principles, follow state‐of‐the‐art techniques while acknowledging relevant prior results, and present exciting discoveries or novel understanding of the fundamental processes that affect solar system objects. JGR‐Planets covers a broad range of topics addressing every aspect of geoscience with the only requirement that the work addresses planetary processes. The wide breadth of topics published is reflected by our editorial team composed in 2023 of associate editors Adrian Brown, Jun Cui, Joel Davis, Leigh Fletcher, Matthias Grott, Ananya Mallik, Germán Martínez, Molly McCanta, Katarina Miljkovic, Naomi Murdoch, Ryan Park, Arianna Piccialli, Andrew Poppe, Beatrix Sánchez‐Cano, Laura Schaefer, Mariek Schmidt, Yasuhito Sekine, Kelsi Singer, Michael Sori, Norihiko Sugimoto, Sonia Tikoo, David Trang, and Zhiyong Xiao in addition to the editors who authored this note. We rely on the expertise of the community to vet the articles submitted to the journal. In 2023, JGR‐Planets benefited from 1,184 reviews provided by 731 unique volunteer referees. We also received help from 19 guest editors working on four active special collections. To these volunteers: We are truly grateful that you chose to dedicate your time and energy to evaluate manuscripts and to advise us on the suitability of each manuscript for JGR‐Planets, often suggesting ways to improve the papers. We know that all our volunteers juggle many duties, both professional and personal. On behalf of the entire editorial board of JGR‐Planets, we express our heartfelt gratitude to the many scientists who support this journal. Thank you! You are performing a valued service to this journal and to the community. Plain Language Summary: The peer review process is the key to ensuring that the articles published in JGR‐Planets are carefully vetted and present thoroughly considered, exciting discoveries or novel understandings of the fundamental processes that affect solar system objects. In 2023, JGR‐Planets benefitted from 1,184 reviews provided by 731 unique reviewers and from the help of 19 guest editors working on four active special collections. We are grateful that so many scientists chose to dedicate their time and energy to evaluating and suggesting ways to improve each submitted manuscript. We also wish to acknowledge our outstanding corps of 23 volunteer associate editors. Scientific publishing is truly a community effort. The entire editorial board of JGR‐Planets wishes to express our heartfelt gratitude to the many scientists who support this journal. Thank you! Key Points: 731 referees provided 1,184 peer reviews of manuscripts in 2023The JGR‐Planets Editorial Board includes 23 volunteer associate editors who provide a crucial serviceThe peer review process is critical to the integrity of JGR‐Planets; the Editorial Board is appreciative of the efforts of these individuals [ABSTRACT FROM AUTHOR]

Gravity inversions have contributed greatly to our knowledge of the interior of planetary bodies and the processes that shaped them. However, previous global gravity inversion methods neglect the inference of mantle density anomalies when using techniques to decrease the non‐uniqueness of the inversion. In this work, we present a novel global gravity inversion algorithm, named THeBOOGIe, suited to inferring global‐scale density anomalies within the crust and mantle of planetary bodies. The algorithm embraces the nonuniqueness inherent in gravity inversions by not prescribing at the outset a density interface or depth range of interest. Instead, the method combines a Bayesian approach with a flexible incorporation of prior geological or geophysical information to infer density anomalies at any depth. A validation test using synthetic lunar‐like gravity data shows that THeBOOGIe can constrain the lateral location of crustal density anomalies but tends to overestimate their thicknesses. Importantly, THeBOOGIe can detect deep mantle density anomalies and quantify the level of confidence in the inferred density models. Our results show that THeBOOGIe can provide complementary information to one‐dimensional seismic models of the interior of the terrestrial planets and the Moon by constraining density anomalies that are not spherically symmetric. Additionally, THeBOOGIe is specially suited to constraining the interior of partially differentiated bodies where these large‐scale density anomalies are more likely to exist. Finally, thanks to the flexible use of priors, THeBOOGIe is an essential tool to understand the interior of planetary bodies lacking additional constraints. Plain Language Summary: Gravity data is often the main constraint on the structure of planetary interiors. However, inferring the density structure of a body from gravity data is inherently non‐unique, due to the tradeoff between density anomaly and distance in the definition of gravity anomalies. Traditional methods circumvent this problem by specifying a priori the source of gravity anomalies to crustal thickness variations while neglecting deeper anomalies. We present here an alternative approach where density anomalies are defined over finite‐size objects and the inversion is conducted within a Bayesian framework. Our algorithm, named THeBOOGIe, is able to recover the location of density anomalies in the mantle of the Moon, although the inferred shallow crustal anomalies are spread over a larger depth range than the actual object producing the gravity anomaly. Our approach provides important complementary information about the interior of planetary bodies than the one provided by traditional inversion methods. Key Points: A novel Bayesian gravity inversion method constrains 3‐D global‐scale density anomalies and provides uncertainty on the resulting modelOur algorithm recovers deep mantle anomalies adequately but dilutes shallow crustal density anomalies over a larger depth rangeOur Bayesian framework is especially suited for inverting the gravity field of planetary bodies that lack additional geophysical constraints [ABSTRACT FROM AUTHOR]

Inversions of planetary gravity are aimed at constraining the mass distribution within a planet or moon. In many cases, constraints on the interior structure of the planet, such as the depth of density anomalies, must be assumed a priori , to reduce the non-uniqueness inherent in gravity inversions. Here, we propose an alternative approach that embraces the non-uniqueness of gravity inversions and provides a more complete view of related uncertainties. We developed a Transdimensional Hierarchical Bayesian (THB) inversion algorithm that provides an ensemble of mass distribution models compatible with the gravitational field of the body. Using this ensemble of models instead of only one, it is possible to quantify the range of interior parameters that produce a good fit to the gravity acceleration data. To represent the interior structure of the planet or moon, we parametrize mass excess or deficits with point masses. We test this method with synthetic data and, in each test, the algorithm is able to find models that fit the gravity data of the body very well. Three of the target or test models used contain only point mass anomalies. When all the point mass anomalies in the target model produce gravity anomalies of similar magnitudes and the signals from each anomaly are well separated, the algorithm recovers the correct location, number and magnitude of the point mass anomalies. When the gravity acceleration data of a model is produced mostly by a subset of the point mass anomalies in the target model, the algorithm only recovers the dominant anomalies. The fourth target model is composed of spherical caps representing lunar mass concentration (mascons) under major impact basins. The algorithm finds the correct location of the centre of the mascons but fails to find their correct outline or shape. Although the inversion results appear less sharp than the ones obtained by classical inversion methods, our THB algorithm provides an objective way to analyse the interior of planetary bodies that includes epistemic uncertainty. [ABSTRACT FROM AUTHOR]