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Regularized Empirical Variance-Covariance-Matrices for stochastic gravity modeling of 8 major ocean tides

This data publication represents the main outcomes of WP1.200 of Individual Project IP1 and Deliverable D1.1 of the research unit NEROGRAV. The goal of WP1.200 was the realistic representation of modern ocean tide model uncertainties in the form of empirical Variance-Covariance Matrices (VCMs) for the utilization in satellite gravimetric dealiasing. In the following, we describe the data set generation and format. A more detailed description of the processing strategy of the data set can be found in Abrykosov et al. (2021).

Rift architecture of the Red Sea from four end-member scenarios

This data repository contains the IGMAS+ (Gotze and Lahmeyer, 1988; Schmidt et al., 2011, 2020) files of the four end-member structural and density models used to analyze the rift architecture of the Red Sea. The user can directly open the files in IGMAS+ (https://igmas.git-pages.gfz-potsdam.de/igmas-pages/, accessed 12.08.2022) to explore the gravity response of these configurations. The end-member scenarios include two end-type margin architectures following Huismans and Beaumont (2011): Type I - outlined by narrow regions (less than about 100 km wide) of thinned continental crust and exhumed (and serpentinized) continental lithospheric mantle along the continent-ocean transition, and Type II - outlined by (ultra)wide regions (up to 500 km) of thin continental crust and the removal of the lithospheric mantle. In addition, we include two options for distribution of oceanic crust in the Red Sea: limited - confined only to regions of magnetic stripes following Schettino et al. (2016), and extended - in which oceanic crust is available in vast areas within the basin, following Augustin et al. (2021).

Ferry Gravimetry Data from the EU FAMOS project

Within the European Union FAMOS project, GFZ performed two gravimetry campaigns on commercial ferries in the Baltic Sea in 2017 and 2018. The nature of such “non-dedicated” campaigns is different from “dedicated” campaigns which are performed on research vessels with tracks planned according to gravity measurement needs. The non-dedicated campaigns use non-survey vessels (e.g. ferries) or survey vessels running for other purposes (e.g. hydrographic measurements). Measurements conducted on such conditions may require additional corrections besides the typical marine gravimetry corrections. We investigated two additional corrections, namely the vertical accelerations due to the motion of the ferry in the vertical direction and the dynamical effect due to the cross-coupling between horizontal and vertical acceleration components. To assess the usefulness of non-dedicated campaigns, we analysed gravity measurements collected on two commercial ferries and demonstrated that the standard processing without the above mentioned two corrections, as used in dedicated campaigns, already delivers good quality end products that fulfil the requirements of a typical marine gravimetry survey with an uncertainty of about 1 mGal for a much lower cost. Therefore, the data published in this contribution is a product of the same algorithm we use for dedicated campaign measurements. Based on our findings, we suggest that gravimetry campaigns on commercial ferries can be used to complement dedicated marine gravimetry campaigns and contribute to geodetic purposes.

3D lithospheric structure of the Caribbean and north South American Plates and Rotation Files of Kinematic Reconstructions back to 90 Ma of the Caribbean Large Igneous Plateau

We are providing the geophysical data used to develop a gravity validated 3D lithospheric configuration of the Caribbean and north South American plates. The sources of these data are described in Section 4 of this README. Republication of subsets of these data are with permission of the authors or allowed by the licences of the input data. This data repository contains the lithospheric layers of the gravity validated 3D structural and density model of the Caribbean and north South American plates. In this model, the integration of different publicly available geophysical datasets was made, after an interpolation to a homogeneous spatial resolution of 25 km was performed. The data repository also contains the average density of the crystalline crust obtained after forward modelling the gravity anomalies. Additionally, the rotation files of the GPlates reconstructions of the Caribbean Large Igneous Plateau (CLIP) back to 90 Ma are included. This kinematic analysis was based on different reconstructions previously published by other authors. Further information and citations are given on the README file associated to this data repository.

Scripts to calculate the Vertical Gravity Gradients response of a 3D lithospheric model using spherical coordinates: the Caribbean oceanic domain as a case study

The scripts and workflow are supplementary material to "3D Modelling of Vertical Gravity Gradients and the delimitation of tectonic boundaries: The Caribbean oceanic domain as a case study" (Gómez-García et al., 2019).The codes include the calculation of the VGG response of a 3D lithospheric model, in spherical coordinates, using the software Tesseroids (Uieda, 2016). The "Readme_Workflow_2019_002.pdf" file provide very detail information about the structure of this repository, as well as the step-by-step for the scripts execution, and the list of the requiered software for the correct workflow performance.All the information provided here will allow the user to reproduce the results and figures of the main paper. Detailed information are also given in the associated README.

Average crustal densities and main terrain boundaries of the Caribbean oceanic domain inferred from the modelling of Vertical Gravity Gradients

These data are supplementary material to "3D Modelling of Vertical Gravity Gradients and the delimitation of tectonic boundaries: The Caribbean oceanic domain as a case study" (Gómez-García et al., 2019).This dataset contains information about the structure of the Caribbean oceanic crust, based on the modelling of the Vertical Gravity Gradients, which are gravity derivatives especially sensitive to density contrasts in the upper layers of the Earth.The files included are:1) The inferred densities of the Caribbean crystalline crust, in the file “CrustalDensities.txt”.2) The residuals of the Vertical Gravity Gradients (VGG), in the file “ResidualsVGG.txt”, which were used to define the terrain boundaries.3) A collection of shapefiles (2019GC008340_Gdb.gdb) with the main inferred tectonic/terrain boundaries and additional geologic features.4) A "Read me" file with the description of the different shapefiles available in the geodatabase.