Located in the interior of the East European Craton (EEC), the Baltic Ordovician–Silurian Basin hosts an elongated tongue-like deep-marine depression, the Livonian Tongue (LT), which extends from Sweden across Latvia and separates the Estonian and Lithuanian shallow-marine shelves. The tectonic origin of the LT has been suggested already since its discovery in the early 1960s. However, the nature of tectonic forces and mechanisms behind the evolution of this narrow intracratonic subsidence zone in the Ordovician–Silurian of the Baltic Basin has remained poorly understood. The origin of the LT can be related to an extensive intracratonic dislocation zone known as the Leba Ridge–Riga–Pskov Fault Zone (LeRPFZ) that coincides largely with the axis of the LT. The LeRPFZ reveals some heavily uplifted basement blocks and has, therefore, been considered as an up-warped anticline-type structure. Recent studies show that the LT has developed in highly complex and changing stress field conditions during the Caledonian orogeny. The subsidence and widening phase of the LT in the Ordovician and early Silurian coincides with, and was possibly governed by, the Avalonia collision with Baltica from the SW when high shear stress forced LeRPFZ blocks to move obliquely towards the NE. As Laurentia was approaching Baltica and finally collided with it in the mid-Silurian, the shear stress became progressively mingled with compression from the NW and the subsidence of the LeRPFZ became reversed, triggering LT withdrawal to the SW. Thus, being once the deep-water centre of the Baltic Ordovician–Silurian Basin, the LT became the most uplifted and intensely eroded EEC interior zone by the Devonian.
Afanasev, B. & Volkolakov, F. 1972. The main tectonic structures of the pre-Devonian Baltic Syneclise sedimentary cover complex. In Regional Geology of the Baltic Countries and Belarus (Ulst, R., ed.), pp. 121–128. Zinatne, Riga [in Russian, with English summary].
Afanasev, B. L., Polivko, I. A., Yakovleva, V. I. & Volkolakov, F. K. 1973. On the problem of genesis of the local structures of the Baltic area. In Issues in the Regional Geology of the Baltic Countries and Belorussia (Kuršs, V. M., ed.), pp. 201–210. Zinatne, Riga [in Russian, with English summary].
Ainsaar, L. 1995. Terrigeenne materjal veetaseme muutuste kajastajana Lõuna-Eesti Ordoviitsiumis [Terrigenous material as an indicator of sea-level changes in the Ordovician of South Estonia]. In Geology of Livonia (Meidla, T., Jõeleht, A., Kalm, V. & Kirs, J., eds), pp. 51–58. Tartu Ülikooli Kirjastus, Tartu [in Estonian, with English summary].
Amantov, A., Hagenfeldt, S. & Söderberg, P. 1995. The Mesoproterozoic to Lower Paleozoic sedimentary bedrock sequence in the Northern Baltic Proper, Åland Sea, Gulf of Finland and Lake Ladoga. In Proceedings of the Third Marine Geological Conference “The Baltic” (Mojski, J. E., ed.), Prace Panstwowego Instytutu Geologicznego, 149, 19–25.
Ankudinov, S., Sadov, A. & Brio, H. 1994. Crustal structure of Baltic countries on the basis of deep seismic sounding data. Proceedings of the Estonian Academy of Sciences, Geology, 43, 129–136 [in Russian, with English summary].
Bassett, M. G., Kaljo, D. & Teller, L. 1989. The Baltic region. In A Global Standard for the Silurian System (Holland, C. H. & Bassett, M. G., eds), pp. 158–170. National Museum of Wales, Geological Series 9.
Bogdanova, S. V., Bingen, B., Gorbatschev, R., Kheraskova, T. N., Kozlov, V. I., Puchkov, V. N. & Volozh, Yu. A. 2008. The East European Craton (Baltica) before and during the assembly of Rodinia. Precambrian Research, 160, 23–45.
https://doi.org/10.1016/j.precamres.2007.04.024
Brangulis, A. 1985. Vend i Kembrij Latvii [The Vendian and Cambrian in Latvia]. Zinatne, Riga, 134 pp. [in Russian].
Brangulis, A. P. & Brio, H. S. 1981. Istoriya razvitiya osnovnykh lokal´nykh podnyatij Zapadnoj i Tsentral´noj Latvii [History of the development of the local uplifts in western and central Latvia]. In Usloviya obrazovaniya osadochnogo chekhla i struktur Pribaltiki [Conditions in the Formation of the Platform Cover and Its Structures in the Baltic Countries] (Afanasev, B. L., ed.), pp. 25–33. Zinatne, Riga [in Russian].
Brenchley, P. J., Carden, G. A., Hints, L., Kaljo, D., Marshall, J. D., Martma, T., Meidla, T. & Nõlvak, J. 2003. High-resolution stable isotope stratigraphy of Upper Ordovician sequences: Constraints on the timing of bioevents and environmental changes associated with mass extinction and glaciation. Geological Society of America Bulletin, 115, 89–104.
https://doi.org/10.1130/0016-7606(2003)115<0089:HRSISO>2.0.CO;2
Brio, H. S., Kucherenko, V. P. & Kursheva, V. F. 1981. Novye dannye o strukturnom plane kaledonskogo etazha v rajone Valmierskogo podnyatiya [New data on the structural setting of the Caledonian structural complex around the Valmiera Uplift]. In Usloviya obrazovaniya osadochnogo chekhla i struktur Pribaltiki [Conditions of the Formation of the Platform Cover and Its Structures in the Baltic Countries] (Afanasev, B. L., ed.), pp. 67–71. Zinatne, Riga [in Russian].
Einasto, R. 1986. Main stages of development and facies models of the East Baltic Silurian pericontinental basin. In Teoriya i opyt ékostratigrafii [Theory and Practice of Ecostratigraphy] (Kaljo, D. & Klaamann, E., eds), pp. 37–54. Valgus, Tallinn [in Russian].
Einasto, R. 1995. “Liivi keele” omapärast Baltika arenguloos [On the role of the Livonian Tongue in the evolution of the Baltic continent]. In Geology of Livonia (Meidla, T., Jõeleht, A., Kalm, V. & Kirs, J., eds), pp. 23–32. Tartu Ülikooli Kirjastus, Tartu [in Estonian, with English summary].
Elo, S. & Korja, A. 1993. Geophysical interpretation of the crustal and upper mantel structure in the Wiborg rapakivi granite area, southeastern Finland. Precambrian Research, 64, 273–288.
https://doi.org/10.1016/0301-9268(93)90081-C
Flodén, T. 1980. Seismic stratigraphy and bedrock geology of the central Baltic. Stockholm Contributions in Geology, 35, 1–240.
Gaál, G. & Gorbatschev, R. 1987. An Outline of the Precambrian evolution of the Baltic Shield. Precambrian Research, 35, 15–52.
https://doi.org/10.1016/0301-9268(87)90044-1
Garetski, R. G., Brangulis, A. P., Gorelik, Z. A., Puura, V. A. & Suveizdis, P. I. (eds). 1978. Tektonicheskaya terminologiya Belorussii i Pribaltiki [Tectonic Terminology of Belarus and Baltic Countries]. Nauka i Tekhnika, Minsk, 268 pp. [in Russian].
Gee, D. G. & Pease, V. (eds). 2004. Timanides – Neoproterozoic Orogeny along the eastern margin of Baltica. Geological Society, London, Memoirs, 30, 1–249.
https://doi.org/10.1144/GSL.MEM.2004.030.01.01
Gee, D. G., Fossen, H., Henriksen, N. & Higgins, A. K. 2008. From the Early Paleozoic Platforms of Baltica and Laurentia to the Caledonide Orogen of Scandinavia and Greenland. Episodes, 31, 44–51.
https://doi.org/10.18814/epiiugs/2008/v31i1/007
Gorbatschev, R. & Bogdanova, S. 1993. Frontiers in the Baltic Shield. Precambrian Research, 64, 3–22.
https://doi.org/10.1016/0301-9268(93)90066-B
Grahn, Y. 1982. Caradocian and Ashgillian Chitinozoa from the subsurface of Gotland. Sveriges Geologiska Undersökning, C788, 1–66.
Grahn, Y. 1995. Lower Silurian Chitinozoa and biostratigraphy of subsurface Gotland. Geologiska Föreningens i Stockholm Förhandlingar, 117, 57–65.
https://doi.org/10.1080/11035899509546199
Grahn, Y. & Nõlvak, J. 2010. Swedish Ordovician Chitinozoa and biostratigraphy: a review and new data. Palaeontographica Abteilung B: Palaeobotany – Palaeophytology, 283, 1–71.
https://doi.org/10.1127/palb/283/2010/5
Hagenfeldt, S. E. 1989. Lower and Middle Cambrian Acritarchs from the Baltic Depression and South-Central Sweden, Taxonomy, Stratigraphy, and Palaeogeographic Reconstruction. Ph.D. thesis, Department of Geology, University of Stockholm, Sweden, 32 pp.
Harris, M. T., Sheehan, P. M., Ainsaar, L., Hints, L., Männik, P., Nõlvak, J. & Rubel, M. 2004. Upper Ordovician sequences of western Estonia. Palaeogeography, Palaeoclimatology, Palaeoecology, 210, 135–148.
https://doi.org/10.1016/j.palaeo.2004.02.045
Jaanusson, V. 1973. Aspects of carbonate sedimentation in the Ordovician of Baltoscandia. Lethaia, 6, 11–34.
https://doi.org/10.1111/j.1502-3931.1973.tb00871.x
Jaanusson, V. 1976. Faunal dynamics in the Middle Ordovician (Viruan) of BaltoScandia. In The Ordovician System. Proceedings of a Paleontological Association, Symposium, Birmingham, September 1974 (Bassett, M. G., ed.), pp. 301–326. University of Wales Press and National Museum of Wales, Cardiff.
Janutyte, I., Majdanski, M., Voss, P. H. & Kozlovskaya, E. 2015. Upper mantle structure around the Trans-European Suture Zone obtained by teleseismic tomography. Solid Earth, 6, 73–91.
https://doi.org/10.5194/se-6-73-2015
Kaljo, D. (ed.). 1970. Silur Éstonii [The Silurian of Estonia]. Valgus, Tallinn, 343 pp. [in Russian, with English summary].
Kaljo, D. (ed.). 1977. Fatsii i fauna Silura Pribaltiki [Facies and Fauna of the Baltic Silurian]. Academy of Sciences of the Estonian SSR, Tallinn, 286 pp. [in Russian, with English summary].
Kaljo, D. & Jürgenson, E. 1977. Fatsial´naya zonal´nost´ Silura Pribaltiki [Sedimentary facies of the East Baltic Silurian]. In Fatsii i fauna Silura Pribaltiki [Facies and Fauna of the Baltic Silurian] (Kaljo, D., ed.), pp. 122–148. Academy of Sciences of the Estonian SSR, Tallinn [in Russian, with English abstract].
Kaljo, D. & Hints, L. 1996. Late Ordovician–Early Silurian succession of palaeoecosystems in Estonia. Paleontological Journal, 30, 693–700.
Kaljo, D., Nestor, H. & Põlma, L. 1988. East Baltic region. In A Global Analysis of the Ordovician–Silurian Boundary (Cocks, L. R. M. & Rickards, R. B., eds), Bulletin of the British Museum (Natural History), Geology, 43, 85–91.
Kaljo, D., Nestor, H., Põlma, L. & Einasto, R. 1991. Pozdneordovikskoe olednenie i ego otrazhenie v osadkonakoplenii Paleobaltijskogo bassejna [Late Ordovician glaciation and its reflection in sediment accumulation of the Paleobaltic basin]. In Vazhneishie bioticheskie sobytiya v istorii zemli [Major Biological Events in Earth History] (Kaljo, D., Modzalevskaya, T. & Bogdanova, T., eds), pp. 66–78. Tallinn [in Russian].
Kaljo, D., Hints, L., Martma, T., Nõlvak, J. & Oraspõld, A. 2004. Late Ordovician carbon isotope trend in Estonia, its significance in stratigraphy and environmental analysis. Palaeogeography, Palaeoclimatology, Palaeoecology, 210, 165–185.
https://doi.org/10.1016/j.palaeo.2004.02.044
Kaljo, D., Martma, T. & Saadre, T. 2007. Post-Hunnebergian Ordovician carbon isotope trend in Baltoscandia, its environmental implications and some similarities with that of Nevada. Palaeogeography, Palaeoclimatology, Palaeoecology, 245, 138–155.
https://doi.org/10.1016/j.palaeo.2006.02.020
Kaljo, D., Hints, L., Männik, P. & Nõlvak, J. 2008. The succession of Hirnantian events based on data from Baltica: brachiopods, chitinozoans, conodonts, and carbon isotopes. Estonian Journal of Earth Sciences, 57, 197–218.
https://doi.org/10.3176/earth.2008.4.01
Kirs, J., Puura, V., Soesoo, A., Klein, V., Konsa, M., Koppelmaa, H., Niin, M. & Urtson, K. 2009. The crystalline basement of Estonia: rock complexes of the Palaeoproterozoic Orosirian and Statherian and Mesoproterozoic Calymmian periods, and regional correlations. Estonian Journal of Earth Sciences, 58, 219–228.
https://doi.org/10.3176/earth.2009.4.01
Kleesment, A., Põlma, L. & Kajak, K. 1980. Contact between the Ordovician and Devonian in South-East Estonia. Proceedings of the Estonian Academy of Sciences, Geology, 1, 8–16 [in Russian, with English summary].
Laitakari, I., Rämö, T., Suominen, V., Niin, M., Stepanov, K. & Amantov, A. 1996. Subjotnian: Rapakivi granites and related rocks in the surroundings of the Gulf of Finland. Geological Survey of Finland, Special Paper, 21, 59–97.
Lazauskiene, J., Sliaupa, S., Brazauskas, A. & Musteikis, P. 2003. Sequence stratigraphy of the Baltic Silurian succession: tectonic control on the foreland infill. Geological Society, London, Special Publications, 208, 95–115.
https://doi.org/10.1144/GSL.SP.2003.208.01.05
Loydell, D. K., Kaljo, D. & Männik, P. 1998. Integrated biostratigraphy of the lower Silurian of the Ohesaare core, Saaremaa, Estonia. Geological Magazine, 135, 769–783.
https://doi.org/10.1017/S0016756898001423
Loydell, D. K., Männik, P. & Nestor, V. 2003. Integrated biostratigraphy of the lower Silurian of the Aizpute-41 core, Latvia. Geological Magazine, 140, 205–229.
https://doi.org/10.1017/S0016756802007264
Loydell, D. K., Nestor, V. & Männik, P. 2010. Integrated biostratigraphy of the lower Silurian of the Kolka-54 core, Latvia. Geological Magazine, 147, 253–280.
https://doi.org/10.1017/S0016756809990574
Lukševičs, E., Stinkulis, Ģ., Mūrnieks, A. & Popovs, K. 2012. Geological evolution of the Baltic Artesian Basin. In Highlights of Groundwater Research in the Baltic Artesian Basin (Dēliņa, A., Kalvāns, A., Saks, T., Bethers, U. & Vircavs, V., eds), pp. 7–52. University of Latvia, Riga.
Männik, P. 2014. The Silurian System in Estonia. In 4th Annual Meeting of IGCP 591, Estonia, 10–19 June 2014, Abstracts and Field Guide (Bauert, H., Hints, O., Meidla, T. & Männik, P., eds), pp.123−128. University of Tartu, Tartu.
Männil, R. 1966. Istoriya razvitiya Baltijskogo bassejna v ordovike [Evolution of the Baltic Basin During the Ordovician]. Valgus, Tallinn, 200 pp. [in Russian, with English summary].
Martinsson, A. 1968. The Ordovician–Silurian hiatus below Gotland. Geologiska Föreningens i Stockholm Förhandlingar, 90, 561–563.
https://doi.org/10.1080/11035896809454943
Meidla, T., Ainsaar, L. & Hints, O. 2014. The Ordovician System in Estonia. In 4th Annual Meeting of IGCP 591, The Early to Middle Paleozoic Revolution, Estonia, 10–19 June 2014, Abstracts and Field Guide (Bauert, H., Hints, O., Meidla, T. & Männik, P., eds), pp. 116−122. University of Tartu, Tartu.
Mens, K. & Pirrus, E. 1997. Vendian–Tremadoc clastogenic sedimentation basins. In Geology and Mineral Resources of Estonia (Raukas, A. & Teedumäe, A., eds), pp. 184–192. Estonian Academy Publishers, Tallinn.
Misans, J. P. & Brangulis, A. P. (eds). 1979. Geologicheskoe stroenie i poleznye iskopaemye Latvii [Geology and Mineral Resources of Latvia]. Zinatne, Riga, 538 pp. [in Russian].
Modliński, Z., Jacyna, J., Kanev, S., Khubldikov, A., Laskova, L., Laskovas, J., Lendzion, K., Mikazane, I. & Pomeranceva, R. 1999. Palaeotectonic evolution of the Baltic Syneclise during the Early Palaeozoic as documented by paleothickness maps. Geological Quarterly, 43, 285–296.
Nestor, H. & Einasto, R. 1977. Facies-sedimentary model of the Silurian Palaeobaltic Pericontinental Basin. In Fatsii i fauna Silura Pribaltiki [Facies and Fauna of the Baltic Silurian] (Kaljo, D., ed.), pp. 89–121. Academy of Sciences of the Estonian SSR, Tallinn [in Russian, with English abstract].
Nestor, H. & Einasto, R. 1997. Ordovician and Silurian carbonate sedimentary basin. In Geology and Mineral Resources of Estonia (Raukas, A. & Teedumäe, A., eds), pp. 192–195. Estonian Academy Publishers, Tallinn.
Nielsen, A. T. & Schovsbo, N. H. 2011. The Lower Cambrian of Scandinavia: Depositional environment, sequence stratigraphy and paleogeography. Earth-Science Reviews, 107, 207–310.
https://doi.org/10.1016/j.earscirev.2010.12.004
Nikishin, A. M., Ziegler, P. A., Stephenson, R. A., Cloetingh, S. A. P. L., Furne, A. V., Fokin, P. A., Ershov, A. V., Bolotov, S. N., Korotaev, M. V., Alekseev, A. S., Gorbachev, V. I., Shipilov, E. V., Lankreijer, A., Bembinova, E. Y. & Shalimov, I. V. 1996. Late Precambrian to Triassic history of the East European Craton: dynamics of sedimentary basin evolution. Tectonophysics, 268, 23–63.
https://doi.org/10.1016/S0040-1951(96)00228-4
Nironen, M. 1997. The Svecofennian Orogen: a tectonic model. Precambrian Research, 86, 21–44.
https://doi.org/10.1016/S0301-9268(97)00039-9
Nõlvak, J. 1987. Rakvere Stage. Nabala Stage. Vormsi Stage. Pirgu Stage. In Geology and Mineral Resources of the Rakvere Phosphorite-Bearing Area (Puura, V., ed.), pp. 63–69. Valgus, Tallinn [in Russian].
Paasikivi, L. B. 1966. Geologicheskoe stroenie i istoriya razvitiya Haanja-Loknovskogo i Mynisteskogo podnyatiya [Geology and development of the Haanja-Lokno and Mõniste uplifts]. Voprosy razvedochnoj geofiziki, 5, 86–97 [in Russian].
Paškevičius, J. 1997. The Geology of the Baltic Republics. Lietuvos Geologijos Tarnyba, Vilnius, 387 pp.
Pease, V., Daly, J. S., Elming, S.-Å., Kumpulainen, R., Moczydlowska, M., Puchkov, V., Roberts, D., Saintot, A. & Stephenson, R. 2008. Baltica in the Cryogenian, 850–630 Ma. Precambrian Research, 160, 46–65.
https://doi.org/10.1016/j.precamres.2007.04.015
Perens, E. 1995. Ülemordoviitsiumist Põltsamaa–Jõgeva–Ruskavere joonel [Upper Ordovician sequence on the Põltsamaa–Jõgeva–Ruskavere line]. In Geology of Livonia (Meidla, T., Jõeleht, A., Kalm, V. & Kirs, J., eds), pp. 45–50. Tartu Ülikooli Kirjastus, Tartu [in Estonian, with English summary].
Põldsaar, K. & Ainsaar, L. 2014. Extensive soft-sediment deformation structures in the early Darriwilian (Middle Ordovician) shallow marine siliciclastic sediments formed on the Baltoscandian carbonate ramp, northwestern Estonia. Marine Geology, 356, 111–127.
https://doi.org/10.1016/j.margeo.2013.08.012
Põldsaar, K., Ainsaar, L., Nemliher, R., Tinn, O. & Stinkulis, G. 2019. A siliciclastic shallow-marine turbidite on the carbonate shelf of the Ordovician Baltoscandian palaeobasin. Estonian Journal of Earth Sciences, 68, 1–14.
https://doi.org/10.3176/earth.2019.01
Polivko, I. A. 1981. Kaledonskaya struktura Pribaltiki [Caledonian structure of the Baltic countries]. In Usloviya obrazovaniya osadochnogo chekhla i struktur Pribaltiki [Conditions of the Formation of the Platform Cover and Its Structures in the Baltic Countries] (Afanasev, B.-L., ed.), pp. 34–45. Zinatne, Riga [in Russian].
Puura, V. & Flodén, T. 1999. Rapakivi-granite–anorthosite magmatism – a way of thinning and stabilisation of the Svecofennian crust, Baltic Sea Basin. Tectonophysics, 305, 75–92.
https://doi.org/10.1016/S0040-1951(99)00019-0
Puura, V. & Tuuling, I. 1988. Geology of the Early Ordovician clastic dikes of Osmussaar. Proceedings of the Academy of Sciences of the Estonian SSR, Geology, 37, 1–9 [in Russian, with English summary].
Puura, V., Amantov, A., Sviridov, N. & Kanev, S. 1991. Tektonika [Tectonics]. In Geologiya and Geomorfologiya Baltijskogo morya [Geology and Geomorphology of the Baltic Sea] (Grigelis, A. A., ed.), pp. 267–290. Nedra, Leningrad [in Russian].
Puura, V., Amantov, A., Tikhomirov, V. & Laitakari, I. 1996. Latest events affecting the Precambrian basement, Gulf of Finland and surrounding areas. Geological Survey of Finland, Special Paper, 21, 115–125.
Schmidt, F. 1891. Einige Bemerkungen über das Baltische Obersilur in Veranlassung der Arbeit des Prof. W. Dames über die Schichtenfolge der Silurbildung Gotlands. Mélanges géologiques et paléontologiques, Bulletin de l´Académie Impériale des Sciences de St. Pétersbourg, 1(1), 119–138.
Šliaupa, S. & Hoth, P. 2011. Geological evolution and resources of the Baltic Sea area from the Precambrian to the Quaternary. In The Baltic Sea Basin (Harff, J., Björck, S. & Hoth, P., eds), pp.13–53. Springer-Verlag, Berlin, Heidelberg.
https://doi.org/10.1007/978-3-642-17220-5_2
Šliaupa, S., Fokin, P., Lazauskienė, J. & Stephenson, R. 2006. The Vendian–Early Palaeozoic sedimentary basins of the East European Craton. In European Lithosphere Dynamics (Gee, D. G. & Stephenson, R. A., eds), Geological Society, London, Memoirs, 32, 449–462.
https://doi.org/10.1144/GSL.MEM.2006.032.01.28
Söderberg, P. 1993. Seismic stratigraphy, tectonics and gas migration in the Åland Sea, northern Baltic Proper. Stockholm Contributions in Geology, 43, 1–67.
Torsvik, T. H. & Cocks, L. R. M. 2013. New global palaeo-geographical reconstructions for the Early Palaeozoic and their generation. In Early Palaeozoic Biogeography and Palaeogeography (Harper, D. A. T. & Servais, T., eds), Geological Society, London, Memoirs, 38, 5–24.
https://doi.org/10.1144/M38.2
Tuuling, I. 2017. Paleozoic rocks structure versus Cenozoic cuesta relief along the Baltic Shield–East European Platform transect. Geological Quartely, 61, 396–412.
https://doi.org/10.7306/gq.1342
Tuuling, I. 2019. The Leba Ridge–Riga–Pskov Fault Zone – a major East European Craton interior dislocation zone and its role in the early Palaeozoic development of the platform cover. Estonian Journal of Earth Sciences, 68, 161–189.
https://doi.org/10.3176/earth.2019.12
Tuuling, I. & Flodén, T. 2000: Late Ordovician carbonate buildups and erosional features north-east of Gotland, northern Baltic Sea. Geologiska Föreningens i Stockholm Förhandlingar, 122, 237–249.
https://doi.org/10.1080/11035890001222237
Tuuling, I. & Flodén, T. 2007. The Ordovician–Silurian boundary beds between Saaremaa and Gotland, Baltic Sea, based on high resolution seismic data. Geological Quarterly, 51, 217–229.
Tuuling, I. & Flodén, T. 2009a. The Llandovery–lowermost Wenlock sequence in the Baltic Sea between Saaremaa and Gotland; subdivision, thicknesses and correlation, based on marine seismic studies. Marine Geology, 267, 55–70.
https://doi.org/10.1016/j.margeo.2009.09.004
Tuuling, I. & Flodén, T. 2009b. Seismic correlation of Palaeozoic rocks across the northern Baltic Proper – Swedish–Estonian project since 1990, a review. Estonian Journal of Earth Sciences, 58, 73–85.
https://doi.org/10.3176/earth.2009.4.06
Tuuling, I. & Flodén, T. 2011. Seismic stratigraphy, architecture and outcrop pattern of the Wenlock–Přidoli sequence offshore Saaremaa, Baltic Sea. Marine Geology, 281, 14–26.
https://doi.org/10.1016/j.margeo.2011.01.003
Tuuling, I. & Vaher, R. 2018. Structure and development of the Valmiera–Lokno Uplift – a highly elevated basement block with a strongly deformed and eroded platform cover in the East European Craton interior around the Estonian–Latvian–Russian borderland. Geological Quarterly, 62, 579–596.
Ulst, R., Gailite, L. & Yakovleva, V. 1982. Ordovik Latvii [The Ordovician of Latvia]. Zinatne, Riga, 294 pp. [in Russian].
Vejelyte, I., Bogdanova, S., Salnikova, E., Yakovleva, S. & Fedoseenko, A. 2010. Timing of ductile shearing within the Drūkšiai–Polotsk Deformation Zone, Lithuania: a U–Pb titanite age. Estonian Journal of Earth Sciences, 59, 256–262.
https://doi.org/10.3176/earth.2010.4.02
Viola, G., Henderson, I. H. C., Bingen, B. & Hendriks, B. W. H. 2011. The Grenvillian–Sveconorwegian orogeny in Fennoscandia: Back‐thrusting and extensional shearing along the “Mylonite Zone”. Precambrian Research, 189, 368–388.
https://doi.org/10.1016/j.precamres.2011.06.005
Volkolakov, F. K. 1974. Strukturnaya pozitsiya podnyatiya Liepaja-more v Baltijskoj Sineklize [Structural setting of the submarine uplift off Liepaja in the Baltic Syneclise]. In Regional´naya geologiya Pribaltiki [Regional Geology of the Baltic Countries] (Sorokin, V. S., ed.), pp. 145–148. Zinatne, Riga [in Russian].
Wannäs, K. O. 1989. Seismic stratigraphy and tectonic development of the Upper Proterozoic to Lower Paleozoic of the Bothnian Bay, Baltic Sea. Stockholm Contributions in Geology, 40, 83–168.
Winterhalter, B., Flodén, T., Ignatius, H. & Axberg, S. 1981. Geology of the Baltic Sea. In The Baltic Sea, Elsevier Oceanography Series (Voipio, A., ed.), pp. 1–117. Elsevier Scientific Company, Amsterdam.
https://doi.org/10.1016/S0422-9894(08)70138-7