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For registration and further information go to: http://www.link.springer.com. Due to the electronic nature of the procedure, the manuscript and the original figures will only be returned to you on special request. When you return your corrections, please inform us if you would like to have these documents returned. Metadata of the article that will be visualized in OnlineFirst ArticleTitle Combined Gravimetric–Seismic Crustal Model for Antarctica Article Sub-Title Article CopyRight Springer Science+Business Media B.V. (This will be the copyright line in the final PDF) Journal Name Surveys in Geophysics Corresponding Author Family Name Tenzer Particle Given Name Robert Suffix Division Department of Land Surveying and Geo-Informatics Organization Hong Kong Polytechnic University Address Kowloon, Hong Kong Phone Fax Email [email protected] URL ORCID Author Family Name Baranov Particle Given Name Alexey Suffix Division Schmidt Institute of Physics of the Earth Organization Russian Academy of Sciences Address Moscow, Russian Federation Division Institute of Earthquake Prediction Theory and Mathematical Geophysics Organization Russian Academy of Sciences Address Moscow, Russian Federation Phone Fax Email URL ORCID Author Family Name Bagherbandi Particle Given Name Mohammad Suffix Division Division of Geodesy and Geoinformatics Organization Royal Institute of Technology (KTH) Address Stockholm, Sweden Division Department of Industrial Development, IT and Land Management Organization University of Gävle Address Gävle, Sweden Phone Fax Email URL ORCID Received 11 May 2017 Schedule Revised Accepted 8 August 2017 Abstract The latest seismic data and improved information about the subglacial bedrock relief are used in this study to estimate the sediment and crustal thickness under the Antarctic continent. Since large parts of Antarctica are not yet covered by seismic surveys, the gravity and crustal structure models are used to interpolate the Moho information where seismic data are missing. The gravity information is also extended offshore to detect the Moho under continental margins and neighboring oceanic crust. The processing strategy involves the solution to the Vening Meinesz-Moritz’s inverse problem of isostasy constrained on seismic data. A comparison of our new results with existing studies indicates a substantial improvement in the sediment and crustal models. The seismic data analysis shows significant sediment accumulations in Antarctica, with broad sedimentary basins. According to our result, the maximum sediment thickness in Antarctica is about 15 km under Filchner-Ronne Ice Shelf. The Moho relief closely resembles major geological and tectonic features. A rather thick continental crust of East Antarctic Craton is separated from a complex geological/tectonic structure of West Antarctica by the Transantarctic Mountains. The average Moho depth of 34.1 km under the Antarctic continent slightly differs from previous estimates. A maximum Moho deepening of 58.2 km under the Gamburtsev Subglacial Mountains in East Antarctica confirmed the presence of deep and compact orogenic roots. Another large Moho depth in East Antarctica is detected under Dronning Maud Land with two orogenic roots under Wohlthat Massif (48–50 km) and the Kottas Mountains (48–50 km) that are separated by a relatively thin crust along Jutulstraumen Rift. The Moho depth under central parts of the Transantarctic Mountains reaches 46 km. The maximum Moho deepening (34–38 km) in West Antarctica is under the Antarctic Peninsula. The Moho depth minima in East Antarctica are found under the Lambert Trench (24–28 km), while in West Antarctica the Moho depth minima are along the West Antarctic Rift System under the Bentley depression (20–22 km) and Ross Sea Ice Shelf (16–24 km). The gravimetric result confirmed a maximum extension of the Antarctic continental margins under the Ross Sea Embayment and the Weddell Sea Embayment with an extremely thin continental crust (10–20 km). Keywords (separated by '-') Antarctica - Crust - Gravity - Ice - Isostasy - Moho - Sediments - Seismic data Footnote Information Journal : Small 10712 Dispatch : 11-8-2017 Pages : 34 Article No. : 9423 h LE h TYPESET MS Code : GEOP-D-17-00046 h44CP h DISK Surv Geophys DOI 10.1007/s10712-017-9423-5 12 3 Combined Gravimetric–Seismic Crustal Model 4 for Antarctica 5 Alexey Baranov1,2 • Robert Tenzer3 • Mohammad Bagherbandi4,5 Author Proof 6 Received: 11 May 2017 / Accepted: 8 August 2017 7 Ó Springer Science+Business Media B.V. 2017 8 Abstract The latest seismic data and improved information about the subglacial bedrock 9AQ1 relief are used in this study to estimate the sediment and crustalPROOF thickness under the 10 Antarctic continent. Since large parts of Antarctica are not yet covered by seismic surveys, 11 the gravity and crustal structure models are used to interpolate the Moho information 12 where seismic data are missing. The gravity information is also extended offshore to detect 13 the Moho under continental margins and neighboring oceanic crust. The processing 14 strategy involves the solution to the Vening Meinesz-Moritz’s inverse problem of isostasy 15AQ2 constrained on seismic data. A comparison of our new results with existing studies indi- 16 cates a substantial improvement in the sediment and crustal models. The seismic data 17 analysis shows significant sediment accumulations in Antarctica, with broad sedimentary 18 basins. According to our result, the maximum sediment thickness in Antarctica is about 19 15 km under Filchner-Ronne Ice Shelf. The Moho relief closely resembles major geo- 20 logical and tectonic features. A rather thick continental crust of East Antarctic Craton is 21AQ3 separated from a complex geological/tectonicECTED structure of West Antarctica by the 22 Transantarctic Mountains. The average Moho depth of 34.1 km under the Antarctic con- 23 tinent slightly differs from previous estimates. A maximum Moho deepening of 58.2 km 24 under the Gamburtsev Subglacial Mountains in East Antarctica confirmed the presence of A1 & Robert Tenzer A2 [email protected] A3 1 Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, Moscow, Russian A4 Federation A5 2 Institute of Earthquake Prediction Theory and Mathematical Geophysics, Russian Academy of A6 Sciences, Moscow, Russian Federation A7 3 Department of Land Surveying and Geo-Informatics, Hong Kong Polytechnic University, A8 Kowloon, Hong Kong A9 4 Division ofUNCORR Geodesy and Geoinformatics, Royal Institute of Technology (KTH), Stockholm, A10 Sweden A11 5 Department of Industrial Development, IT and Land Management, University of Ga¨vle, Ga¨vle, Sweden 123 Journal : Small 10712 Dispatch : 11-8-2017 Pages : 34 Article No. : 9423 h LE h TYPESET MS Code : GEOP-D-17-00046 h44CP h DISK Surv Geophys 25 deep and compact orogenic roots. Another large Moho depth in East Antarctica is detected 26 under Dronning Maud Land with two orogenic roots under Wohlthat Massif (48–50 km) 27 and the Kottas Mountains (48–50 km) that are separated by a relatively thin crust along 28 Jutulstraumen Rift. The Moho depth under central parts of the Transantarctic Mountains 29 reaches 46 km. The maximum Moho deepening
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