Boundary between the East European Craton and the orogens of South-Western Europe
The Trans-European Suture Zone (TESZ), also known as the Tornquist Zone, is the crustal boundary between the Precambrian East European Craton and the Phanerozoicorogens of South-Western Europe. The zone runs from the North Sea to the Black Sea. The north-western part of the zone was created by the collision of Avalonia and Baltica/East European Craton in the Late Ordovician. The south-eastern part of the zone, now largely concealed by deep sedimentary basins, developed through Variscan and Alpine orogenic events.
Various branches of the TESZ go under different names:
The Teisseyre-Tornquist Zone (TTZ) in Ukraine and Poland.
The Trans-European Fault (TEF), Thor-Tornquist Suture or Thor Suture through southern Denmark.
The latter two branches (STZ and TEF) span a triangular area of numerous faults, called the Tornquist Fan.[1][2][3][4]
Discovery
In 1893 the Polish geologist Wawrzyniec Teisseyre suggested the existence of a buried tectonic line close to the Carpathian Mountains. As part of his work on a Geological Atlas of Galicia he mapped the line from Galicia in Ukraine to south-eastern Poland. In 1908 the German geologist Alexander Tornquist mapped the continuation of the zone from Poland to Scania in Sweden.[5]
Tornquist Fan
Whereas the south-eastern part of the TESZ (Teisseyre-Tornquist Zone) is relatively well-confined, the north-western part divides into numerous sutures and faults, which fan out towards the North Sea and the Iapetus Suture which runs between the Scandinavian and Scottish Caledonides. It includes the following linear features (sorted from the north-east):
The Fennoscandian Border Zone (FBZ) in Skagen and Kattegat
The Moho under the Tornquist Fan has a strong topography with depths varying between 26 and 48 km. It started forming during the Caledonian orogeny as a microcontinent or a series of terranes of Avalonian origin amalgamated with Baltica. Faults are believed to have continued forming until late Paleozoic.[7]
Teisseyre-Tornquist Zone
The Teisseyre-Tornquist Zone (TTZ), extending from Pomerania at the Baltic Sea to the Dobruja at the Black Sea, is primarily known from geophysical studies. Seismic data and gravity models suggest a strong contrast in crustal thickness, with 28–35 km down to the Moho to the west of the suture and 42–47 km to the east of it. The suture is believed to be buried under thick upper Paleozoic and Mesozoic sediments, and located further west than indicated by historical surface observations.[8][9][10]
See also
Tornquist Sea – Sea between the palaeocontinents Avalonia and Baltica about 600 to 450 million years ago
^Thybo, H. (1997). "Geophysical characteristics of the Tornquist Fan area, northwest Trans-European Suture Zone: Indication of late Carboniferous to early Permian dextral transtension". Geological Magazine. 134 (5): 597–606. doi:10.1017/s0016756897007267. S2CID129418419.
^Hans Thybo, Crustal structure and tectonic evolution of the Tornquist Fan region as revealed by geophysical methods, Bulletin of the Geological Society of Denmark, Vol. 46, pp. 145-160, http://2dgf.dk/xpdf/bull46-2-145-160.pdf
^Mazur, S., M. Mikolajczak, P. Krzywiec, M. Malinowski, V. Buffenmyer, and M. Lewandowski (2015), Is the Teisseyre-Tornquist Zone an ancient plate boundary of Baltica?, Tectonics, 34, doi:10.1002/2015TC003934, http://onlinelibrary.wiley.com/doi/10.1002/2015TC003934/full