Tectonophysics 846 (2023) 229656 Available online 25 November 2022 0040-1951/© 2022 Elsevier B.V. All rights reserved. New insights of the crustal structure across Estonia using satellite potential felds derived from WGM-2012 gravity data and EMAG2v3 magnetic data Juan David Solano-Acosta * , Alvar Soesoo , Rutt Hints Department of Geology, Tallinn University of Technology, Ehitajate tee 5, Tallinn, Estonia A R T I C L E INFO Keywords: Estonian basement Gravity and magnetic potential felds Moho and Conrad discontinuities Curie depth point (CPD) Heat fow Structural lineaments ABSTRACT Global WGM-12 gravity and EMAG2v3 magnetic models were used to present new information of the Estonian crust. The Estonian Precambrian crystalline basement, composed of Paleo-Meso Proterozoic metamorphic and igneous rocks, is covered by a Paleozoic sedimentary rock deposit 100–800 m thick. The present work aims to map structural patterns and recognise physical layers of the crust over Estonia using global potential models. The gravimetric data was used to identify the depth of the Moho and Conrad discontinuities. The magnetic data has been processed to calculate the Curie point depth (CPD), which was then used to estimate heat fow (HF) values in the study area. The depth of the Moho indicates an average value of 60 km, while the average depth of the Conrad discontinuity is around 18 Km. The depth of the CPD reveals an average value of 15 km. Different de- rivative techniques were applied over the residual part of both potential models, to delineate and map geophysical lineaments. The subsurface of Estonia has been divided into six petrological-structural zones: Tal- linn, Alutaguse, J˜ ohvi, West-Estonian, Tapa and South-Estonian. Geophysical lineaments in each zone subsurface division delineates a NW-SE trend, perpendicular to the NE-SW oriented Fenno-Sarmatian collision. To visualise the anomalous crustal variations over Estonia, different profles showing varying values of potential felds, CPD and heat fow are presented, especially around the Precambrian Rapakivi granitic plutons and in the Paldiski- Pskov deformation zone, due to the high contrast observed by mapping the different results over these areas. 1. Introduction Gravity and magnetic potential methods are useful geophysical techniques for identifying and mapping subsurface geological struc- tures, and are commonly used to delineate lineaments and deep crustal layers (Forsberg and Olesen (2010); Hu et al. (2015); Altino˘ glu et al. (2015); Essa et al. (2018); Khazri and Gabtni (2018); Bba et al. (2019); Dilalos et al. (2019); Osagie et al. (2021); Peredo et al. (2021); Omietimi et al. (2021); Dumais et al. (2021)). In Estonia previous geophysical researches has been carried out (Ankudinov et al. (1994); All et al. (2004); Oja et al. (2019); Soesoo et al. (2020); Plado et al. (2020)), however some of the gravity and magnetic data corresponds to data of the last century (Maasik (1959); All et al. (2004)), and there are no recent publications of potential feld trends, or crust structure, not to mention the lack of geophysical analysis derived from global models based on satellite data (i.e., WGM 2012 gravity model (Bonvalot et al. (2012)) and EMAG2v3 magnetic model (Meyer et al. (2017))). The gravity and magnetic surveys are a non-destructive remote sensing geophysical methods to determine rock physical changes in the subsurface geology (i.e. density and remanent magnetisation of mate- rials). As a result, they are a sum of regional and residual potential anomalies (Petit et al. (2002)). The Bouguer anomaly (BA) represents the response of any density change below the surface (Karcol et al. (2017)), and has been widely used to understand subsurface structures and trends, as well as depth-to-basement and its structures, and sedi- mentary basin inflls (Olesen et al. (2010); Nasuti et al. (2012); Fairhead (2012); Karcol et al. (2017); Khazri and Gabtni (2018); Bba et al. (2019); Dilalos et al. (2019); Omietimi et al. (2021)). Induced and remnant magnetisation of the crust and upper mantle are the primary sources of crustal magnetic felds. The difference in magnetic mineral concentration is a good indicator of the structure and composition of the crust (Hope and Eaton (2002); Aitken and Betts (2008)). Magnetic anomaly maps provide insight into the subsurface structure and composition of the Earth's crust (Nakanishi et al. (1992); Golynsky et al. (2002); Purucker and Whaler (2007); Quintero et al. (2019)). Over continental areas, magnetic anomalies illuminate geologic, tectonic, and geothermal evolution of crust and lithosphere (Milligan et al. (2003); Hemant and Maus (2005); Aitken and Betts * Corresponding author. E-mail addresses: jusola@ttu.ee (J.D. Solano-Acosta), alvar.soesoo@taltech.ee (A. Soesoo), rutt.hints@taltech.ee (R. Hints). Contents lists available at ScienceDirect Tectonophysics journal homepage: www.elsevier.com/locate/tecto https://doi.org/10.1016/j.tecto.2022.229656 Received 20 April 2022; Received in revised form 14 November 2022; Accepted 19 November 2022