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Mechthild Doll

Doktorand_innen

Gruppe: 

Allgemeine Geologie - Marine Geologie

Telefon: 

+49 421 218-65055

E-Mail:

Raum: 

GEO 1130

Mechthild Doll

Research interests

  • Marine geology
  • Mud volcanism
  • Fluid seepage
  • Gas hydrates
  • Hydrothermal systems

PhD Project

Calabrian Arc Mud Volcanoes - Deep Origin, internal Structure and Activity

Mud vol­ca­noes (MVs) may be found in ma­ri­ne and ter­restri­al geo­lo­gi­cal set­tings but are pre­do­mi­nant­ly known from com­pres­sio­nal tec­to­nic re­gimes (e.g. ac­cre­tio­na­ry wed­ges). In ge­ne­ral, mud vol­ca­nism is dri­ven by the up­ward mi­gra­ti­on of over­pres­su­red fluids in­du­cing a se­di­ment mo­bi­liza­t­i­on and the ex­tru­si­on of fluids and solids, as mud breccia, onto the sur­face. The re­pea­ting ex­tru­si­on of mud brec­cia leads to a build-up of an edi­fice from which in­di­vi­du­al mud­flows may pro­gres­s down­s­lo­pe.  MVs are ty­pi­cal­ly lin­ked to hy­dro­c­ar­bon sys­tems and, un­der cer­tain tem­pe­ra­tu­re and pres­su­re con­di­ti­ons, able to host gas hy­dra­tes wi­t­hin the se­di­ment.

The Ca­la­bri­an Arc is si­tua­ted in the Eas­tern Me­di­ter­ra­ne­an Sea east of Si­ci­ly. About 54 dis­tinct MVs have been iden­ti­fied in this re­gi­on. The ge­ne­ral role of the Ca­la­bri­an Arc MVs is re­la­tive­ly po­or­ly un­ders­tood but its pre­sence can be ea­si­ly re­la­ted to an ac­cre­tio­na­ry com­plex ex­ten­ding over 1500 km from Ca­la­bria to Cy­prus.

The PhD Pro­ject is fo­cu­sing on a bet­ter un­der­stan­ding of the deep ori­gin, in­ter­nal struc­tu­re, tem­po­ral evo­lu­ti­on and ac­tivi­ty of the Ca­la­bri­an Arc MVs using se­di­men­to­lo­gi­cal and geo­phy­si­cal data of three ex­pe­di­ti­ons (M112, POS499, POS515). High re­so­lu­ti­on ba­thy­me­try data are used to cha­rac­te­ri­ze mud­flows and dis­tin­gu­ish in­di­vi­du­al seaf­loor ex­pres­si­ons of the MVs. In ad­di­ti­on, back­scat­ter data are used to iden­ti­fy mud­flows in the shal­low se­abed. Mo­re­o­ver, the in­ter­pre­ta­ti­on of 2D and 3D seis­mic data is used to de­scri­be the de­eper struc­tu­re of the MVs in the Ca­la­bri­an Arc in more de­tail. Fi­nal­ly, se­di­ment co­res are ex­ami­ned to de­scri­be the ac­tivi­ty and in­di­vi­du­al mud ex­tru­si­on events of the in­di­vi­du­al MVs over the past. On sediment cores, further analyses as e.g. tephrochronology and 14C dating methods are used to get a better understanding of the individual MV history.

The re­sults cont­ri­bu­te to a bet­ter un­der­stan­ding of the for­ma­ti­on and evo­lu­ti­on of Ca­la­bri­an Arc MVs as well as the tec­to­nic ac­tivi­ty behaviour in the Eas­tern Me­di­ter­ra­ne­an Sea. Mo­re­o­ver, the re­sults will im­pro­ve the know­ledge about MVs in terms of on­go­ing chan­ges and to re­con­struct its evo­lu­ti­on over the past.

CV

03/2019 - present

PhD student in the working group General Geology - Marine Geology, Marum/University of Bremen, Germany

PhD Thesis: Calabrian Arc Mud Volcanoes - Deep Origin, internal Structure and Activity

10/2015 - 02/2018

Master of Sciences in Marine Geosciences at the University of Bremen, Germany

Master Thesis: Disturbed temperature-depth profiles in gas hydrate-bearing sediments - Effects of phase transformation

02/2016 - 07/2016 Semester abroad, Master of Sciences Earth Sciences at the University of Waikato, Hamilton, New Zealand
10/2011 - 07/2015

Bachelor of Sciences in Geosciences at the University of Bremen, Germany

Bachelor Thesis: High resolution multi-channel seismic and acoustic investigations of the Helgoland Mud Area in the Southern German Bight, North Sea

 

Research cruises

09/2016 - 10/2016 RV Polarstern Cruise PS101, Karasik Seamount expedition, Alfred-Wegener-Institute Bremerhaven. Cruise Report PS101
06/2015 - 07/2015 RV Sonne Cruise SO241, MAKS expedition Guaymas Basin, Geomar Helmholtz Centre for Ocean Research Kiel. Cruise Report SO241
07/2014 - 08/2014 RV Polarstern Cruise PS86, Aurora vent field expedition, Alfred-Wegener-Institute Bremerhaven. Cruise Report PS86

 

Publications

Dziadek, R., Doll, M., Warnke, F., Schlindwein, V. (2021) Towards Closing the Polar Gap: New Marine Heat Flow Observations in Antarctica and the Arctic Ocean. Geosciences, 11 (11). https://doi.org/10.3390/geosciences11010011

Geilert, S., Hensen, C., Schmidt, M., Liebetrau, V., Scholz, F., Doll, M., Deng, L., Fiskal, A., Lever, M. A., Su, C.-C., Schloemer, S., Sarkar, S., Thiel, V., Berndt, C. (2018) On the formation of hydrothermal vents and cold seeps in the Guaymas Basin, Gulf of California. Biogeosciences, 15: 1-17. https://doi.org/10.5194/bg-15-5715-2018

Møller, M. H., Glombitza, C., Lever, M. A., Deng, L. Morono, Y., Ignaki, F., Doll, M, Su, C.-C., Lomstein, B.A. (2018) D:L-Amino Acid Modeling Reveals Fast Microbial Turnover of Days to Months in the Subsurface Hydrothermal Sediment of Guaymas Basin. Frontiers in Microbiology 9 (967). https://doi.org/10.3389/fmicb.2018.00967

Berndt, C., Hensen, C., Mortera-Gutierrez, C., Sarkar, S., Geilert, S., Schmidt, M., Liebetrau, V., Kipfer, R., Scholz, F., Doll, M., Muff, S., Karstens, J., Planke, S., Petersen, S., Böttner, C., Chi, W.-C., Moser, M., Behrendt, R., Fiskal, A., Lever, M. A., Su, C.-C., Deng, L., Brennwald, M. S., Lizzeralde, D. (2016) Rifting under steam – how rift magmatism triggers methane venting from sedimentary basins, Geology, Vol. 44 (9):767-770. https://doi.org/10.1130/G38049.1

 

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