Mechthild Doll

University of Bremen, Geo - Mechthild Doll

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

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.

Sarkar, S., Moser, M., Berndt, C., Doll, M., Böttner, C., Chi, W.-C., Klaeschen, D., Galerne, C., Karstens, J., Geilert, S., Mortera-Gutierrez, C., Hensen, C. (2022) Thermal state of the Guaymas Basin derived from gas hydrate bottom simulating reflections and heat flow measurements. Journal of Geophysical Research: Solid Earth (accepted, in production). https://doi.org/10.1029/2021JB023909

Lagostina, L., Frandsen, S., MacGregor, B., Glombitza, C., Deng, L., Fiskal, A., Li, J., Doll, M., Geilert, S., Schmidt, M., Scholz, F., Bernasconi, S. M., Jorgensen, B. B., Hensen, C., Teske, A., Lever, M. A. (2021) Interactions between temperature and energy supply drive microbial communities in hydrothermal sediment. Communications biology, 4 (1006). https://doi.org/10.1038/s42003-021-02507-1

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