Dr. rer. nat. Benjamin Walter

Dr. rer. nat. Benjamin Walter

  • Adenauerring 20b
    76131 Karlsruhe

Current position

Assistant Professor/Research fellow

Present Projects

I am interested in all kind of fluids responsible for ore-formation in magmatic, metamorphic, sedimentary and hydrothermal settings. My major research focus is to decipher processes leading to ore formation in carbonatites, alkaline-rocks and hydrothermal vein-type deposits. My current projects are:

Alkaline silicate rocks and carbonatites

  • The influence of crustal contamination on a late-stage REE-mineralization in carbonatites (collaboration with Gregor Markl, Michael Marks, Johannes Giebel, Tübingen)
  • The role of late-stage fluids in carbonatite and alkaline silicate rocks (collaboration with Gregor Markl, Michael Marks, Johannes Giebel, Tübingen)
  • The mineralogical control of geophysical exploration signatures (HiTech AlkCarb project)
  • New geomodels for exploring carbonatites and alkaline silicate rocks (HiTech AlkCarb project)
  • The genesis of the South African and Namibian alkaline provinces province (collaboration with Gregor Markl, Michael Marks, Johannes Giebel, Tübingen)
  • Reconstruction of hydrothermal system in volcanoes of the East African rift (collaboration with Will Hutchinson, St Andrews, Scotland)
  • Petrology and age-constrains of the SW-German alkaline province (collaboration with Gregor Markl and Michael Marks, Tübingen; Jens Grimmer KIT)
  • Shallow plumbing systems in alkaline and carbonatite complexes (HiTech AlkCarb project)

Hydrothermal vein type deposits

  • Trace element systematics of hematite-hosted fluid inclusions (cooperation with Gregor Markl, Michel Marks, Tübingen and Matthew Steele-MacInnis, Edmonton, Canada)
  • Mineralogical changes within a single vein and the relation to superregional events
  • Deciphering fluid migration pathways (cooperation with Mathias Burisch, Freiberg)
  • The geochemistry of native arsenic and arsenides in hydrothermal vein-type deposits (cooperation with Gregor Markl and Manuel Scharrer, Tübingen)
  • The genesis of ore shoots in hydrothermal veins (cooperation with Gregor Markl and Manuel Scharrer, Tübingen)
  • Kinetics of ore precipitation in hydrothermal systems

Other projects I contribute:

  • Dolomitization in oil reservoirs (cooperation with Adrian Immenhauser and Anton Kolchugin, Kazan, Russia)
  • How to bring hydrocarbons into crystalline basement rocks? (cooperation with Graham Banks, GEUS Copenhagen)
  • Testing the resilience of ancient early diagenetic dolomites as archives of their palaeo-environment (cooperation with Adrian Immenhauser and Mathias Müller, Bochum)

Past projects

  • Petrology of the Kaiserstuhl
  • Fluid evolution of continental basement brines by microthermometry and crush leach analyses
  • Ore forming processes in hydrothermal vein-type deposits, Schwarzwald, Germany
  • Stable isotope chemistry of hydrothermal vein-type deposits
  • Mg-isotope systematics of hydrothermal carbonates (cooperation with A. Immenhauser, RUB Bochum, Germany)
  • Ore petrography and ore chemistry of hydrothermal vein-type deposits
  • Ore fluid evolution in the continental crystalline basement
  • Ore precipitation processes by LA-ICPMS analyses of single fluid inclusions (cooperation with C. Heinrich & M. Wälle ETH Zürich, Switzerland)
  • U-Pb age-dating of hydrothermal gangue and ore minerals (cooperation with A. Gerdes, Frankfurt, Germany)
  • Evolution of fluid pathways in crystalline basement (cooperation with C. Heinrich & M. Wälle ETH Zürich, Switzerland)
  • Multi-aquifer fluid mixing processes as first order processes for ore precipitation


Fluid Inclusion short course

This 1 SWS short course provides basic knowledge in microthermometrical analyses and data interpretation.

Field Trip: Hydrothermal ore forming processes, Schwarzwald

This 3 day field trip provides basic knowledge in mapping ore mineralizations in the field, relationship of host rock and hydrothermal veins and ore forming processes.

Field Trip: Isle of Mull, Scotland (2018)

Mapping Course Elba, Italy

Mapping Course Syros/Naxos, Greece



Personal information

Dipl. Mineraloge, Postdoc, supervisor of the microthermometry and cathodoluminescence microscopy labs

2006-2012 Diploma in Geoscience, Eberhard Karls University, Tuebingen

2012-2016 Ph.D in Mineralogy, Eberhard Karls University, Tübingen

Ph.D. thesis: Ore forming processes in hydrothermal vein-type deposits, Schwarzwald, Germany

5/2016 Postdoc, Eberhard Karls University, Tübingen (HiTech AlkCarb project)

The HiTech AlkCarb project is funded under the European Union's Horizon 2020 Research and Innovation programme, to develop new geomodels and sustainable exploration methods for alkaline igneous rocks and carbonatites (http://www.bgs.ac.uk/HiTechAlkCarb/). I was project partner in the EKUT team and we work in the Kaiserstuhl SW Germany on science question 1 in work package 2: „How can we predict what intrusive rocks are present at depth using volcanic carbonatites and alkaline rocks exposed at the surface?“


Journal Articles
New Insights on the formation of the Jingchong Cu-Co-Pb-Zn deposit, South China: Evidence from sphalerite mineralogy and muscovite 40Ar-39Ar dating
Peng, E.; Kolb, J.; Walter, B. F.; Frenzel, M.; Patten, C. G. C.; Xu, D.; Wang, Y.; Gan, J.; Beranoaguirre, A.; Wang, Z.
2023. Ore Geology Reviews, Article no: 105667. doi:10.1016/j.oregeorev.2023.105667
Gravitational collapse of a volcano edifice as a trigger for explosive carbonatite eruption?
Rapprich, V.; Walter, B. F.; Kopačková-Strnadová, V.; Kluge, T. M.; Čejková, B.; Pour, O.; Hora, J., M.; Kynický, J.; Magna, T.
2023. The Geological Society of America bulletin, (14 S.). doi:10.1130/B37013.1Full textFull text of the publication as PDF document
The raw material potential of SW-Germany – A brief overview
Walter, B. F.; Kolb, J.
2023. SGA news, 53, 1–4
The genesis of hydrothermal veins in the Aukam valley SW Namibia– A far field consequence of Pangean rifting?
Walter, B. F.; Giebel, R. J.; Siegfried, P.; Doggart, S.; Macey, P.; Schiebel, D.; Kolb, J.
2023. Journal of Geochemical Exploration, 250, Article no: 107229. doi:10.1016/j.gexplo.2023.107229
The eruption interface between carbonatitic dykes and diatremes – The Gross Brukkaros volcanic field Namibia
Walter, B. F.; Giebel, R. J.; Siegfried, P. R.; Gudelius, D.; Kolb, J.
2023. Chemical Geology, 621, Art.-Nr.: 121344. doi:10.1016/j.chemgeo.2023.121344
Orogenic Au deposits with atypical metal association (Cu, Co, Ni): insights from the Pohjanmaa Belt, western Finland
Hector, S.; G. C. Patten, C.; Kolb, J.; de Araujo Silva, A.; Walter, B. F.; Molnár, F.
2023. Ore Geology Reviews, Art.-Nr.: 105326. doi:10.1016/j.oregeorev.2023.105326Full textFull text of the publication as PDF document
Journal Articles
A tale of three fluids : fluid-inclusion and carbonate clumped-isotope paleothermometry reveals complex dolomitization and dedolomitization history of the latemare platform
Müller, M.; Walter, B. F.; Swart, P. K.; Jöns, N.; Jacquemyn, C.; Igbokwe, O. A.; Immenhauser, A.
2022. Memorabilia, 92 (12), 1141–1168. doi:10.2110/jsr.2022.047
Two distinct age groups of melilitites, foidites, and basanites from the southern Central European Volcanic Province reflect lithospheric heterogeneity
Binder, T.; Marks, M. A. W.; Gerdes, A.; Walter, B. F.; Grimmer, J.; Beranoaguirre, A.; Wenzel, T.; Markl, G.
2022. International Journal of Earth Sciences, 112 (3), 881–905. doi:10.1007/s00531-022-02278-yFull textFull text of the publication as PDF document
Alkaline-Silicate REE-HFSE Systems
Beard, C. D.; Goodenough, K. M.; Borst, A. M.; Wall, F.; Siegfried, P. R.; Deady, E. A.; Pohl, C.; Hutchison, W.; Finch, A. A.; Walter, B. F.; Elliott, H. A. L.; Brauch, K.
2022. Economic Geology, 118 (1), 177–208. doi:10.5382/econgeo.4956Full textFull text of the publication as PDF document
Tectonic setting, fluid inclusion and gold mineralization of the southwest Poli region (northern Cameroon Domain)
Ngounouno, F. Y.; Negue, E. N.; Kolb, J.; Walter, B.; Teda Soh, A. C.; Patten, C.; Ngounouno, I.
2022. Journal of African Earth Sciences, 194, Art.-Nr.: 104579. doi:10.1016/j.jafrearsci.2022.104579
The Kieshöhe carbonatites of southwestern Namibia – the post-magmatic role of silicate xenoliths on REE mobilisation [in press]
Walter, B. F.; Giebel, R. J.; Marlow, A. G.; Siegfried, P. R.; Marks, M.; Markl, G.; Palmer, M.; Kolb, J.
2022. Communications of the Geological Survey Namibia, 25, 1–31
The formation of (Ni-Co-Sb)-Ag-As ore shoots in hydrothermal galena-sphalerite-fluorite veins
Scharrer, M.; Epp, T.; Walter, B.; Pfaff, K.; Vennemann, T.; Markl, G.
2022. Mineralium deposita, 57, 853–885. doi:10.1007/s00126-021-01059-y
Constraints on the preservation of proxy data in carbonate archives – lessons from a marine limestone to marble transect, Latemar, Italy
Mueller, M.; Jacquemyn, C.; Walter, B. F.; Pederson, C. L.; Schurr, S. L.; Igbokwe, O. A.; Jöns, N.; Riechelmann, S.; Dietzel, M.; Strauss, H.; Immenhauser, A.
2022. Sedimentology, 69 (2), 423–460. doi:10.1111/sed.12939Full textFull text of the publication as PDF document
Journal Articles
Fluids associated with carbonatitic magmatism: A critical review and implications for carbonatite magma ascent
Walter, B. F.; Giebel, R. J.; Steele-MacInnis, M.; Marks, M. A. W.; Kolb, J.; Markl, G.
2021. Earth science reviews, 215, Art. Nr.: 103509. doi:10.1016/j.earscirev.2021.103509
Journal Articles
Combining Ion Chromatography and Total Reflection X-ray Fluorescence for Detection of Major, Minor and Trace Elements in Quartz-hosted Fluid Inclusions
Ladenburger, S.; Walter, B. F.; Marks, M. A. W.; Markl, G.
2020. Journal of analytical chemistry, 75 (11), 1477–1485. doi:10.1134/S106193482011009X
A comparative study of two Mississippian dolostone reservoirs in the Volga-Ural Basin, Russia
Kolchugin, A.; Immenhauser, A.; Morozov, V.; Walter, B.; Eskin, A.; Korolev, E.; Neuser, R.
2020. Journal of Asian earth sciences, 199, 104465. doi:10.1016/j.jseaes.2020.104465
Formation of native arsenic in hydrothermal base metal deposits and related supergene U6+ enrichment: The Michael vein near Lahr, SW Germany
Scharrer, M.; Sandritter, K.; Walter, B. F.; Neumann, U.; Markl, G.
2020. American mineralogist, 105 (5), 727–744. doi:10.2138/am-2020-7062
Complex carbonate-sulfate brines in fluid inclusions from carbonatites: Estimating compositions in the system H2O-Na-K-CO3-SO4-Cl
Walter, B.; Steele-MacInnis, M.; Giebel, R. J.; Marks, M. A. W.; Markl, G.
2020. Geochimica et cosmochimica acta, 277, 224–242. doi:10.1016/j.gca.2020.03.030
Formation of hydrothermal fluorite-hematite veins by mixing of continental basement brine and redbed-derived fluid: Schwarzwald mining district, SW-Germany
Walter, B. F.; Jensen, J. L.; Coutinho, P.; Laurent, O.; Markl, G.; Steele-MacInnis, M.
2020. Journal of geochemical exploration, 212, Article: 106512. doi:10.1016/j.gexplo.2020.106512
Testing the preservation potential of early diagenetic dolomites as geochemical archives
Mueller, M.; Igbokwe, O. A.; Walter, B.; Pederson, C. L.; Riechelmann, S.; Richter, D. K.; Albert, R.; Gerdes, A.; Buhl, D.; Neuser, R. D.; Bertotti, G.; Immenhauser, A.
2020. Sedimentology, 67 (2), 849–881. doi:10.1111/sed.12664Full textFull text of the publication as PDF document

Publications until 2018


Epp,T. , Walter, B.F., Scharrer, M., Lehmann, G., Henze, K., Heimgärtner, C., Bach, W. and Markl, G. (2018): Quartz with associated Sb-Pb-Ag±Au mineralization in the Schwarzwald, SW Germany: a record of metamorphic cooling, tectonic rifting and element remobilization processes in the Variscan belt. Mineralium Deposita. DOI: 10.1007/s00126-018-0855-8 

Braunger, S., Marks, M.A.W., Walter, B.F., Neubauer, R., Reich, R., Wenzel, T., Parsapoor Anis & Markl, G. (2018). The Petrology of the Kaiserstuhl Volcanic Complex, SW Germany: The Importance of Metasomatized and Oxidized Lithospheric Mantle for Carbonatite Generation. Journal of Petrology. Journal of Petrology 59 (9), 1731-1762.

Walter, B.F., Gerdes, A., Kleinhanns, I. C., Dunkl, I., von Eynatten, H., Kreissl, S., & Markl, G. (2018): The connection between hydrothermal fluids, mineralization, tectonics and magmatism in a continental rift setting: fluorite Sm-Nd and hematite and carbonates U-Pb geochronology from the Rhinegraben in SW Germany. Geochimica et Cosmochimica Acta 240, 11-42.

Walter B.F., Parsapoor A., Braunger S., Marks M.A.W., Wenzel T., Martin M., Markl G. (2018): Pyrochlore as a monitor for magmatic and hydrothermal processes in carbonatites from the Kaiserstuhl volcanic complex (SW Germany). Chemical Geology 498, 1-16.

Keim, M. F., Walter, B. F., Neumann, U., Kreissl, S., Bayerl, R. & Markl, G. (2018): Polyphase enrichment and redistribution processes in silver-rich mineral associations of the hydrothermal fluorite-barite-(Ag-Cu) Clara deposit, SW Germany. Mineralium Deposita 53, 1-20.

Kreissl, S., Gerdes, A., Walter, B.F., Neumann, U., Wenzel, T. and Markl, G. (2018): Reconstruction of a >200 Ma multi-stage “five element” Bi-Co-Ni-Fe-As-S system in the Penninic Alps, Switzerland. Ore Geology Reviews.

Walter, B.F., Burisch, M., Fusswinkel, T., Marks, M.A.W., Steele-MacInnis, M., Wälle, M., Apukhtina, O., Markl, G. (2018): Multi-reservoir fluid mixing processes in rift-related hydrothermal veins, Schwarzwald, SW-Germany. Journal of Geochemical Exploration 186, 158-186.

Burisch, M., Walter, B.F., Gerdes, A., Lanz, M. and Markl, G. (2018): Late-stage anhydrite-gypsum-siderite-dolomite-calcite assemblages record the transition from a deep to a shallow hydrothermal system in the Schwarzwald mining district, SW Germany. Geochimica and Cosmochimica Acta 223, 259-278.


Walter, B.F., Steele-MacInnis, M. and Markl, G. (2017): Sulfate brines in fluid inclusions of hydrothermal veins: Compositional determinations in the system H2O-Na-Ca-Cl-SO4. Geochimica et Cosmocimica Acta, 209, 184-203.

Burisch, M., Walter, B.F. and Markl, G. (2017): Silification of hydrothermal gangue minerals in Pb-Zn-Cu-fluorite-quartz-baryte veins. Canadian Mineralogist 55, 1-14.

Walter, B.F., Burisch, M., Marks, M.A.W. & Markl, G. (2017): Major element composition of fluid inclusions from hydrothermal vein-type deposits record eroded sedimentary Units in the Schwarzwald district, SW Germany. Mineralium Deposita 52(8), 1191-1204.


Burisch, M., Gerdes, A., Walter, B.F., Neumann, U., Fettel, M. and Markl, G. (2016): Methane and the origin of five-element veins: Mineralogy, age, fluid inclusion chemistry and ore forming processes in the Odenwald, SW Germany. Ore Geology Reviews. DOI:10.1016/j.oregeorev.2016.10.033

Walter, B.F., Burisch, M., Markl, G. (2016): Long-term chemical Evolution and modification of Continental Basement brines - a field study from the Schwarzwald, SW Germany. Geofluids. DOI: 10.1111/gfl.12167.

Burisch, M., Walter, B.F., Wälle, M. and Markl, G. (2016): Tracing fluid migration pathways in root zone below unconformity-related hydrothermal veins: Insights from trace element systematics of individual fluid inclusions. Chemical Geology 429, 44-50.

Kolchugin, A., Immenhauser, A., Walter, B., Morozov, V.P. (2016): Diagenesis of the palaeo-oil-water transition zone in a Lower Pennsylvanian carbonate reservoir: Constraints from cathodoluminescence microscopy, microthermometry, and isotope geochemistry. Marine and Petroleum Geology 72, 45-61.


Walter, B.F., Immenhauser, A., Geske, A. and Markl, G. (2015): Exploration of hydrothermal Carbonate Magnesium isotop signatures as Tracers for Continental fluid aquifers, Schwarzwald mining district, SW Germany. Chemical Geology 400, 87-105.

Bons, P.; Fusswinkel, T.; Gomez-Rivas, E; Markl, G.; Wagner, T.; Walter, B. (2014): Fluid mixing from below in unconformity-related hydrothermal ore deposits. Geology 42(12), 1035-1038.


Fieldwork Namibia Dez 2019


HiTech AlkCarb field trip Namibia 2018

HiTech AlkCarb field trip Greenland 2017

HiTech AlkCarb field trip Scotland 2017

HiTech AlkCarb field trip Malawi 2016