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Sie sind hier: Startseite Arbeitsgruppen Geochemie Mitarbeiter Dr. Frank Tomaschek

Dr. Frank Tomaschek

wiss. Mitarbeiter

Frank Tomaschek

 

 

 

 

 

Kontakt

Poppelsdorfer Schloss
Raum 2.105

Telefon: +49 228 73-2938
E-Mail:  ftom [at] uni-bonn.de

 

Research

After undergraduate studies on poly-metamorphic rocks of the Alpine crystalline basement, I enjoyed the blending of petrological and geochronological approaches to address geological problems for high-pressure metamorphic rocks of the Cycladic Islands. I have particularly grown interest in questions relating to factors controlling the relative stability and transformation mechanisms of zircon solid solutions in natural and experimental systems. More recently, I have been studying the U-Pb system of silica, fossil biogenic apatite and silicified wood, aiming to unravel the history of low temperature, hydrous alteration, or the long-term diagenetic evolution. I’m presently part of the DFG research unit FOR 2685 on fossilization processes.

Teaching

From 2015 to 2018, I was teaching introductory courses on igneous and metamorphic petrology (“Endogene Prozesse”), introduction to geochemistry on the BSc level, gave individual lectures on the U-Pb system, and participated in the teaching of mineralogy and Raman spectroscopy on the BSc and MSc level. Since 2018, I’m responsible for teaching the optical mineralogy courses. I have been leading and co-leading various field excursions to the Eifel, Siebengebirge, and Kaiserstuhl volcanism, the Evje-Iveland pegmatite field (Norway), and high-pressure metamorphism of the Cyclades (Syros, Greece).

I’m always interested to work with motivated students to go after interesting geochemical and petrological questions. Supervised BSc and MSc theses include:

  • Deniz Öz: Titanite and uraninite geochronology of the Evje-Iveland Pegmatite Field, South-Norway (MSc 09/2018).
  • Felix Mihm: Mineralogische und geochemische Untersuchungen an „Skolezitachat“ aus Rheinhessen (BSc 09/2018).
  • Michael Scheil: U-Pb systematics of fossil biogenic apatite from the Morrison Formation (USA) and the Langenberg Quarry (Germany) (MSc 08/2018).
  • Alicia Krick: Petrographische und geochemische Untersuchungen von verkieseltem Holz aus dem Escalante Petrified Forest State Park in Utah (USA) (BSc 08/2018).
  • Florencia Egger: Petrographische und geochemische Untersuchungen fossiler Knochen aus Tendaguru (Tansania) (BSc 08/2018).
  • Felix Graeber: Laser ablation U-Pb analysis of fossil bone apatite (BSc 09/2017).
  • Anika Braun: Petrographische Untersuchungen und Uran-Blei-Datierung von Hydrothermaliten aus dem Erzgebirge (BSc 09/2017).
  • Leoniedas Reschke: Uran-Blei-Datierung des Siebengebirgs-Vulkanismus‘ (BSc 03/2017).

Reviewed Articles

  • Pohl, F., Froitzheim, N., Obermüller, G., Tomaschek, F., Schröder, O., Nagel, T., Sciunnach, D. & Heuser, A. (2018). Kinematics and age of syn-intrusive detachment faulting in the Southern Alps: evidence for Early Permian crustal extension and implications for the Pangea A vs. B controversy. Tectonics 37. doi: 10.1029/2018TC004974.
  • Baldwin, L.C., Tomaschek, F., Ballhaus, C., Gerdes, A., Fonseca, R.O.C., Wirth, R., Geisler, T. & Nagel, T. (2017). Petrogenesis of alkaline basalt-hosted sapphire megacrysts. Petrological and geochemical investigations of in-situ sapphire occurrences from the Siebengebirge Volcanic Field, Germany. Contributions to Mineralogy and Petrology 172, 43. doi:10.1007/s00410-017-1362-0.
  • Nilius, N.-P., Froitzheim, N., Nagel, T.J., Tomaschek, F. & Heuser, A. (2016). The Schwarzhorn Amphibolite (Eastern Rätikon, Austria): an Early Cambrian intrusion in the Lower Austroalpine basement. Geologica Carpathica 67, 121-132.
  • Hellawell, J., Ballhaus, C., Gee, C.T., Mustoe, G.E., Nagel, T.J., Wirth, R., Rethemeyer, J., Tomaschek, F., Geisler, T., Greef, K. & Mansfeldt, T. (2015). Incipient silicification of recent conifer wood at a Yellowstone hot spring. Geochimica et Cosmochimica Acta 149, 79-87.
  • Keiter, M., Ballhaus, C. & Tomaschek, F. (2011). A new geological map of the Island of Syros (Aegean Sea, Greece): Implications for lithostratigraphy and structural history of the Cycladic Blueschist Unit. GSA Special Papers 481, 1-43.
  • Soman, A., Geisler, T., Tomaschek, F., Grange, M. & Berndt, J. (2010). Alteration of crystalline zircon solid solutions: a case study on zircon from an alkaline pegmatite from Zomba-Malosa, Malawi. Contributions to Mineralogy and Petrology 160, 909-930.
  • Tomaschek, F., Keiter, M., Kennedy, A.K. & Ballhaus, C. (2008). Pre-Alpine basement within the northern Cycladic Blueschist Unit on Syros Island, Greece. In: Xypolias, P. & Zulauf, G. (eds.): Eastern Mediterranean. Zeitschrift der Deutschen Gesellschaft für Geowissenschaften 159, 521-532.
  • Keiter, M., Tomaschek, F. & Ballhaus, C. (2008). The structural inventory of Kythnos Island (Cyclades, Greece) – a reconnaissance. In: Xypolias, P. & Zulauf, G. (eds.): Eastern Mediterranean. Zeitschrift der Deutschen Gesellschaft für Geowissenschaften 159, 513-520.
  • Lagos, M., Scherer, E.E., Tomaschek, F., Münker, C., Keiter, M., Berndt, J. & Ballhaus, C. (2007). High precision Lu-Hf geochronology of Eocene eclogite facies rocks from Syros, Cyclades, Greece. Chemical Geology 243, 16-35.
  • Geisler, T., Schaltegger, U. & Tomaschek, F. (2007). Re-equilibration of zircon in aqueous fluids and melts. In: Harley, S.L. & Kelly, N.M. (eds.): Zircon: Tiny but Timely. Elements 3, 43-50.
  • Tomaschek, F., Kennedy, A.K., Villa, I.M., Lagos, M. & Ballhaus, C. (2003). Zircons from Syros, Cyclades, Greece - Recrystallization and mobilization of zircon during high-pressure metamorphism. Journal of Petrology 44, 1977-2002.
  • Geisler, T., Rashwan, A.E.A, Rahn, M.K.W., Poller, U., Zwingmann, H., Pidgeon, R.T., Schleicher, H. & Tomaschek, F. (2003). Low-temperature alteration of natural metamict zircons from the Eastern Desert, Egypt. Mineralogical Magazine 67, 485-507.

Conference Abstracts

  • Braun, A., Tomaschek, F., Lagos, M. & Geisler, T. (2018). U-Pb dating of hydrothermal vein agate using LA-ICP-MS. GeoBonn 2018, Book of Abstracts, 138.
  • Graeber, F., Tomaschek, F., Lagos, M., Sander, P.M. & Geisler T. (2018). U-Pb analyses of fossil bone apatite from the Upper Jurassic Morrison Formation (USA). GeoBonn 2018, Book of Abstracts, 256.
  • Klug, L., Froitzheim, N., Tomaschek, F. & Lagos M. (2018). Pre-Variscan U-Pb zircon ages of the Texel Complex and the Schneeberg Complex (Austroalpine, Italy). GeoBonn 2018, Book of Abstracts, 43.
  • Scheil, M., Tomaschek, F., Sander, P.M., Lagos, M. & Geisler, T. (2018). Age determation of fossil teeth and bones using the U-Pb decay system. GeoBonn 2018, Book of Abstracts, 259.
  • Öz, D., Tomaschek, F., Lagos, M., Werner, R. & Geisler, T. (2018). Titanite U-Pb geochronology of the Evje-Iveland Pegmatite Field, Norway. GeoBonn 2018, Book of Abstracts, 142.
  • Klug, L., Schmidtke, M.J., Tomaschek, F., Lagos, M. & Froitzheim, N. (2018). Deformation and geochronology of metamorphic rocks in the Saltauser Tal, Italy. TSK 17 Jena 2018 Abstracts Volume, 66.
  • Tomaschek, F., Ballhaus, C., Geisler, T., Gee, C.T. & Heuser, A. (2016). U-Pb tracing of aqueous alteration events in silicified wood from Lesvos, Greece. 25th International Workshop on Plant Taphonomy, Bonn.
  • Nilius, N.-P., Froitzheim, N., Nagel, T.J., Tomaschek, F. & Heuser, A. (2016). From early Cambrian arc magmatism to Jurassic rifting: Tectonic evolution of the Lower Austroalpine Schwarzhorn Amphibolite (Eastern Rätikon, Austria). Abstract Volume of GeoTirol2016 - Annual Meeting of DGGV and PANGEO Austria, Innsbruck, 237.
  • Obermüller, G., Pohl, F., Tomaschek, F., Heuser, A., Froitzheim, N., Sciunnach, D. & Schröder, O. (2016). Permian detachment faulting and syntectonic magmatism constrained by U-Pb LA-ICP-MS on zircon in the Orobic Anticline, Italy. Abstract Volume of GeoTirol2016 - Annual Meeting of DGGV and PANGEO Austria, Innsbruck, 238.
  • Tomaschek, F., Ballhaus, C., Heuser, A. & Geisler, T. (2016). Vein opal from Lesvos (Greece): U-Pb dating of extensional tectonics? TSK 16 Bonn 2016 Scientific Program, 55.
  • Obermüller, G., Pohl, F., Tomaschek, F., Heuser, A., Froitzheim, N., Sciunnach, D. & Schröder, O. (2016). Permian detachment faulting, syntectonic magmatism and Alpine thrusting in the Orobic Alps, Southern Alps, Italy. TSK 16 Bonn 2016 Scientific Program, 39.
  • Tomaschek, F., Heuser, A., Nemchin, A. & Geisler, T. (2015). Replacement of uraniferous opal by chalcedony and disturbance of the U-Pb system. GeoBerlin2015 - Abstracts, 371-372.
  • Tomaschek, F., Heuser, A., Nemchin, A. & Geisler, T. (2015). Replacement of wood opal by chalcedony: Implications for U-Pb geochronology. Goldschmidt 2015 Abstracts, 3145.
  • Baldwin, L.C., Tomaschek, F., Gerdes, A., Fonseca, R.O.C. & Ballhaus, C. (2015). Implications for a carbonated peridotite source for intra-continental alkaline mafic lavas from the Siebengebirge volcanic field (Germany). Goldschmidt2015 Abstracts, 183.
  • Tomaschek, F., Nemchin, A., Geisler, T., Heuser, A. & Merle, R. (2015). U-Pb geochronology of hydrous silica (Siebengebirge, Germany). Geophysical Research Abstracts 17, EGU2015-12377.
  • Pohl, F., Froitzheim, N., Tomaschek, F., Heuser, A., Nagel, T. & Schröder O. (2014). Permian detachment faulting, syntectonic magmatism and Alpine thrusting in the Orobic Alps, southern Alps, Italy. GeoFrankfurt 2014, B05_B06, 107.
  • Tomaschek, F., Nemchin, A., Geisler, T., Heuser, A. & Merle, R. (2014). U-Pb dating of opaline silica (Siebengebirge, Rhenish Massif). DMG 92nd Annual Meeting Jena 2014 Programme, 353.
  • Nilius, N.-P., Froitzheim, N., Nagel, T. & Tomaschek, F. (2014). The Schwarzhorn Amphibolite (Eastern Rätikon, Austria): an Early Cambrian intrusion in the Lower Austroalpine basement. TSK 15 Potsdam 2014 Program & Abstracts, 38.
  • Pohl, F., Froitzheim, N., Tomaschek, F., Nagel, T. & Schröder, O. (2014). Permian detachment faulting, syntectonic magmatism and the relation to Alpine thrusting in the Orobic Anticline, southern Alps, Italy. TSK 15 Potsdam 2014 Program & Abstracts, 39.
  • Tomaschek, F., Nemchin, A., Merle, R. & Geisler, T. (2013). U-Pb dating of silcretes in the Siebengebirge (Rhenish Massif, Germany). DMG-GV Tübingen 2013 Conference Abstracts, 312.
  • Merle, R., Nemchin, A., Simons, S., Tomaschek, F. & Geisler, T. (2013). Rates of natural silica precipitation through time. Mineralogical Magazine 77(5), 1742.
  • Tomaschek, F. & Schmid-Beurmann, P. (2012). In situ HT-XRD Study of Zircon - Tackling Inconsistencies in Thermal Expansion Data. European Mineralogical Conference 1, EMC2012-606.
  • Tomaschek, F. & Schmid-Beurmann, P. (2010). In situ HT-XRD study probing for an alleged displacive phase transition in zircon. 88th Annual Meeting of the German Mineralogical Society DMG, 19th - 22th September 2010 in Münster, Abstracts, P8-11.
  • Soman, A., Geisler, T., Tomaschek, F., Berndt, J. & Putnis, A. (2008). Hydrothermal alteration of an alkali pegmatite from Zomba-Malosa (Malawi). 86th Annual Meeting of the German Mineralogical Society DMG, 14th - 17th September 2008 in Berlin, Abs. No. 363.
  • Tomaschek, F., Keiter, M., Kennedy, A.K. & Ballhaus, C. (2008). Indication of pre-Alpine basement gneisses within the northern Cycladic Blueschist Unit on Syros Island, Greece. Geotectonic Research 95, Special Issue 1, 171-173.
  • Keiter, M., Tomaschek, F., Schmidt-Beurmann, P., Ballhaus, C. & Löns, J. (2008). Calcite needles in marbles on Syros (Cyclades, Greece) - Indicators for an obscured aragonite foliation and static exhumation. Geotectonic Research 95, Special Issue 1, 81-82.
  • Soman, A., Geisler, T., Tomaschek, F., Berndt, J. & Putnis, A. (2008). Multi-stage hydrothermal alteration of accessory minerals from an alkali pegmatite from Zomba-Malosa (Malawi). Conference Supplement to Geochimica et Cosmochimica Acta 72, A882.
  • Godelitsas, A., Astilleros, J.M., Hallam, K., Wright, K., Tomaschek, F. & Putnis, A. (2007). Interaction of calcite with Cr(III) and evidence for direct inorganic formation of vaterite. Conference Supplement to Geochimica et Cosmochimica Acta 71, A333.
  • Soman, A., Geisler, T., Tomaschek, F. & Putnis, A. (2007). Re-equilibration of natural pyrochlore from Malawi in aqueous fluids. Frontiers in Mineral Sciences 2007, Programme and Abstracts, 199-200.
  • Geisler, T. & Tomaschek, F. (2006). Re-equilibration textures in zircon: what are we actually dating? Berichte der Deutschen Mineralogischen Gesellschaft, Beihefte zum European Journal of Mineralogy 17 (1), 44.
  • Soman, A., Tomaschek, F., Berndt, J., Geisler, T. & Scherer, E.E. (2006). Hydrothermal re-equilibration of zircon from an alkali pegmatite of Malawi. Berichte der Deutschen Mineralogischen Gesellschaft, Beihefte zum European Journal of Mineralogy 17 (1), 132.
  • Tomaschek, F., Lagos, M., Keiter, M. & Ballhaus, C. (2005). The tectonic units from Syros (Greece) and correlations in the Cyclades. Berichte der Deutschen Mineralogischen Gesellschaft, Beihefte zum European Journal of Mineralogy 17 (1), 138.
  • Lagos, M., Scherer, E.E., Münker, C., Tomaschek, F. & Ballhaus, C. (2005). The age of peak metamorphism on Syros (Cyclades, Greece) constrained by high precision Lu-Hf geochronology. Berichte der Deutschen Mineralogischen Gesellschaft, Beihefte zum European Journal of Mineralogy 17 (1), 80.
  • Tomaschek, F., Lagos, M., Keiter, M., Kennedy, A.K. & Ballhaus, C. (2005). Cretaceous and Eocene metamorphic events from Syros (Cyclades, Greece). International Symposium on the Geodynamics of Eastern Mediterranean: Active Tectonics of the Aegean, Kadir Has University, Istanbul, Turkey, Abstracts Volume, 68.
  • Keiter, M., Tomaschek, F. & Ballhaus, C. (2005). Lithostratigraphic and structural news on the history of Syros. International Symposium on the Geodynamics of Eastern Mediterranean: Active Tectonics of the Aegean, Kadir Has University, Istanbul, Turkey, Abstracts Volume, 43.
  • Tomaschek, F. (2004). Zircon reequilibration by dissolution-reprecipitation: reaction textures from flux-grown solid solutions. Berichte der Deutschen Mineralogischen Gesellschaft, Beihefte zum European Journal of Mineralogy 16 (1), 147.
  • Godelitsas, A., Tomaschek, F. & Putnis, A. (2004). Direct nanoscale observations of mixed REE phosphate crystal growth on the dissolved surface of REE fluorocarbonate minerals. Conference Supplement to Geochimica et Cosmochimica Acta 68, A135.
  • Tomaschek, F. (2004). Transient porosity at reaction fronts: Replacement textures from flux-grown zircon. Conference Supplement to Geochimica et Cosmochimica Acta 68, A184.
  • Tomaschek, F., Löns, J. & Ballhaus, C. (2003). Reconnaissance experimental study and thermobarometric implications of zircon-xenotime solid-solutions. Berichte der Deutschen Mineralogischen Gesellschaft, Beihefte zum European Journal of Mineralogy 15 (1), 206.
  • Lagos, M., Münker, C., Tomaschek, F., Ballhaus, C. & Scherer, E.E. (2003). Formation age of oceanic crust and timing of HP/LT-metamorphism on Syros (Cyclades, Greece) based on Lu-Hf geochronology. Berichte der Deutschen Mineralogischen Gesellschaft, Beihefte zum European Journal of Mineralogy 15 (1), 114.
  • Tomaschek, F. & Ballhaus, C. (2003). Zircon-xenotime solid-solubility: an experimental study. Geophysical Research Abstracts 5, 13283.
  • Lagos, M., Münker, C., Tomaschek, F., Ballhaus, C. & Scherer, E.E. (2003). The age of oceanic crust and HP/LT-metamorphism on Syros (Cyclades, Greece) based on Lu-Hf geochronology and geochemistry. Geophysical Research Abstracts 5, 12851.
  • Tomaschek, F. & Löns, J. (2002). Crystal properties of turbid microporous zircon – a single crystal XRD study. Berichte der Deutschen Mineralogischen Gesellschaft, Beihefte zum European Journal of Mineralogy 14 (1), 166.
  • Lagos, M., Münker, C., Tomaschek, F. & Ballhaus, C. (2002). Geochemistry and Lu-Hf-geochronology of the metavolcanic Grizzas sequence in northern Syros (Cyclades, Greece). Beiheft zum European Journal of Mineralogy 14 (1), 97.
  • Tomaschek, F., Kennedy, A., Keay, S. & Ballhaus, C. (2001). Geochronological constraints on Carboniferous and Triassic magmatism in the Cyclades: SHRIMP U-Pb ages of zircons from Syros, Greece. Journal of Conference Abstracts 6 (1), 315.
  • Ballhaus, C., Tomaschek, F., Keiter, M., Bode, M., Lagos, M., Piepjohn, C. & Münker, C. (2001). Magmatic, metamorphic and exhumation history of Syros, Greece. Journal of Conference Abstracts 6 (1), 345.
  • Tomaschek, F., Kennedy, A., Villa, I.M. & Ballhaus, C. (2001). Case study of metamorphic zircons from Alpine HP/LT metamorphic rocks of Syros, Cyclades, Greece. Journal of Conference Abstracts 6 (1), 678.
  • Lagos, M., Münker, C., Tomaschek, F. & Ballhaus, C. (2001). The mobility of Zr-Hf, REE, Th and U in metavolcanic rocks under eclogite facies conditions. Journal of Conference Abstracts 6 (1), 434.
  • Tomaschek, F., Baumann, A., Villa, I.M., Kennedy, A. & Ballhaus, C. (2000). Geochronological constraints on a Cretaceous metamorphic event from the Vari Unit (Syros, Cyclades, Greece). Berichte der Deutschen Mineralogischen Gesellschaft, Beihefte zum European Journal of Mineralogy 12 (1), 214.
  • Tomaschek, F., Kennedy, A., Villa, I.M. & Ballhaus, C. (2000). Zircon pseudomorphs in Alpine HP/LT metamorphic rocks from Syros, Cyclades. Berichte der Deutschen Mineralogischen Gesellschaft, Beihefte zum European Journal of Mineralogy 12 (1), 214.
  • Tomaschek, F., Kennedy, A., Keay, S. & Ballhaus, C. (2000). U/Pb-SHRIMP results for zircons from Syros, Greece: geochronological constraints on Carboniferous and Triassic magmatic episodes in the Cyclades. Terra Nostra 2000/5, 58.
  • Scheuvens, D., Tomaschek, F., Krass, T. & Blümel, P. (2000). Petrostructural evolution in the western part of the Austroalpine Campo crystalline complex (northern Italy): Variscan and Alpine Imprints. Terra Nostra 2000/5, 49.
  • Tomaschek, F., Kennedy, A., Villa, I.M. & Ballhaus, C. (2000). Correlation of Ar-Ar paragonite and U-Pb zircon ages from HP/LT metamorphic units of Syros (Cyclades, Greece). Terra Nostra 2000/1, 124.
  • Münker, C., Weyer, S., Rehkämper, M., Metzger, K., Tomaschek, F. & Krogstadt, E. (1999). The 92Nb-92Zr short-lived nuclide system: high precision Zr isotope measurements by MC-ICPMS. EOS Transactions, Supplement 80 (46), 1077.
  • Tomaschek, F. & Ballhaus, C. (1999). Subduction-related Cretaceous metamorphism in the Attic Cycladic Crystalline Complex on the Island of Syros. Tübinger Geowissenschaftliche Arbeiten Series A 52, 61-62.
  • Ballhaus, C., Tomaschek, F. & Keay, S. (1999). Stratigraphy and age relations on the Island of Syros, Greece. Journal of Conference Abstracts 4 (1), 71-72.
  • Tomaschek, F. & Ballhaus, C. (1999). The Vari Unit on Syros (Aegean Sea) and its relation to the Attic-Cycladic Crystalline Complex. Journal of Conference Abstracts 4 (1), 72.
  • Tomaschek, F. & Blümel, P. (1998). Eoalpine medium-grade metamorphism in the Austroalpine Campo Basement at Passo di Gávia (Northern Italian Alps). Terra Nostra 98/1, 78.
  • Tomaschek, F., Ballhaus, C., Schumacher, J.C. & Frost, B.R. (1997). Die Vari-Einheit auf Syros: Tektonometamorphe Entwicklung und Position. Berichte der Deutschen Mineralogischen Gesellschaft, Beihefte zum European Journal of Mineralogy 9 (1), 356.
  • Tomaschek, F. & Blümel, P. (1997). Polymetamorphic evolution of the Austroalpine Basement at Passo di Gávia (Southern Ortler Cevedale Group, Italian Alps). Terra Abstracts 9 (1), 680.
  • Tomaschek, F. (1996). Das Oberostalpine Grundgebirge im Raum Passo di Gavia (Campo Basement; Südliche Ortler-Cevedale Gruppe, Italienische Alpen). In: Amman, G. (Hrsg.): Erweiterte Kurzfassungen, Symposium TSK 6, Facultas-Universitätsverlag, Wien, S. 427-430.
     

 

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