We use speleothems as archives to reconstruct past climate. Speleothems are secondary mineral deposits in caves. The most common forms are dripstones such as stalagmites, stalactites, and flowstones. Speleothems offer numerous advantages as climate archives:

  • They occur in almost all regions of the world.
  • They can be absolutely dated with unparalleled precision using the 230Th/U dating method over an age range of up to approx. 650,000 years.
  • Various indicators of past climate, known as climate proxies, such as stable oxygen and carbon isotopes and trace element concentrations, can be measured at very high resolution down to sub-annual scale.
  • They provide continuous time series extending far back in time.

In our laboratory, we use state-of-the-art mass spectrometric methods (MC-ICP-MS, LA-ICP-MS), which enable the highest possible accuracy in age determination as well as very high spatial and temporal resolution in the measurement of climate proxies.

The climate signals stored in speleothems are influenced by a wide range of factors. To interpret the signals with regard to past climate variability, a fundamental understanding of the processes influencing these signals is required. The work group therefore also focuses on investigating and modelling isotope fractionation processes. To this end, experiments are carried out both in caves and under controlled conditions in the laboratory.

  • A high-resolution quantitative reconstruction of mean annual temperature for Central Europe over the last 13,300 years using annually laminated speleothems from southern Germany (PI: Dana Riechelmann, Co-PI: Denis Scholz)

  • Quantitative estimation of prior calcite precipitation in speleothems using Ca isotopes (δ44/42Ca): application to precisely dated European multi-proxy time series between MIS 11 and the Holocene (PI: Michael Weber, Co-PI: Denis Scholz)

  • Paleoclimate time series from speleothems from Northeast India (Meghalaya) (PhD: Dildi, PI: Denis Scholz)

  • Junior Professorship for High-Resolution Sedimentology, Institute of Geosciences, JGU Mainz – Investigation of past climate at sub-annual to annual resolution using congruent imaging procedures (PIs: Igor Obreht, Denis Scholz, Philip Pogge von Strandmann)

Academic staff

Laboratory management

PhD Students

Depending on the analytical method, various devices are available for sample preparation and extraction:

  • Rock saws (Buehler Lapro Slap Saw, Buehler IsoMet low-speed cutter, Proxxon micro band saw)
  • Drilling equipment (Proxxon Micromot drilling and milling device, Hilti drill, Metabo drill, Proxxon micro mill)
  • New Wave Reserach MicroMill
  • ESI MicroMill 2
  • Ir Strip Heater
  • Microscopes (Leica DM750P, Leica S8 APO)

Contact persons: Prof. Dr. Denis Scholz, Susann Denndorf

In our cleanroom laboratory, we carry out sample preparation for mass spectrometric analysis. Using ion-exchange column chromatography, the elements to be analysed are separated from the sample matrix (carbonate, gypsum, phosphates, aqueous solutions).

Contact persons: Prof. Dr. Denis Scholz, Susann Denndorf

LA-ICP-MS (“Laser Ablation – Inductively Coupled Plasma – Mass Spectrometry”) is a sensitive analytical method for rapid multi-element determination in the trace and ultra-trace range in solid sample materials and technical products. The sample material to be analysed is ablated using a focused laser beam and transported with a carrier gas (argon or helium) into the inductively coupled plasma ion source of the ICP-MS. In the plasma, which is approx. 8000°C hot, the tiny sample particles are atomised and positively ionised, accelerated, and transported into the high vacuum of the mass spectrometer. There, they are separated according to their mass-to-charge ratio and energy-to-charge ratio and detected with time resolution. The resulting laser craters are only a few µm in size, which means this minimally invasive method is also well suited for valuable material (museum objects, gemstones). At the Geosciences laboratory of Mainz university, LA-ICP-MS has been used since 2004 in trace element analysis to characterise samples from the fields of geology, Mineralogy, climate research, materials science, gemstone research, archaeology, and isotope analysis, e.g. for U-Pb dating of zircons.

Contact persons: Dr. Regina Mertz, Prof. Dr. Denis Scholz

MC-ICP-MS (“Multi Collector – Inductively Coupled Plasma – Mass Spectrometry”) is a highly sensitive analytical method for the precise determination of isotope ratios in the trace and ultra-trace range in solid and liquid sample materials. The sample material to be analysed is transported either directly via laser ablation or, after prior wet-chemical preparation in the cleanroom laboratory, with a carrier gas into the inductively coupled plasma ion source of the ICP-MS. In the plasma, which is approx. 8000°C hot, the tiny sample particles are atomised and positively ionised, accelerated, and transported into the high vacuum of the mass spectrometer. There, they are separated according to their energy-to-charge ratio and mass-to-charge ratio and simultaneously detected with time resolution in several detectors of differing sensitivity.

In our laboratory, we have been measuring various isotope systems on different geoscientific sample materials since 2019. One focus is high-precision dating of carbonates over the last 650,000 years using the 230Th/U method, including in-situ via laser ablation. We also focus on the following isotope systems: strontium, calcium, magnesium, and lithium.

Contact persons: Prof. Dr. Denis Scholz, Dr. Regina Mertz, Dr. Michael Weber

Our group conducts laboratory experiments on speleothem growth and the associated isotope fractionation using a setup that is unique worldwide. In a climate chamber, temperature, humidity, pCO2, the isotopic composition of atmospheric CO2, and drip water can be set and controlled. As in a natural cave, synthetic speleothems can be precipitated from dripping or flowing very thin solution films. This allows us to investigate the influence of various environmental parameters such as temperature and drip rate on the isotopic composition of speleothems under controlled conditions.

Contact person: Prof. Dr. Denis Scholz

Interested in BSc/MSc theses in Speleothem Research? Please feel free to contact us at any time. Your own proposals are very welcome.

Compulsory module: Paleoclimate

  • Paleoclimate lecture
  • Paleoclimate practice class
  • Practice class: Academic writing and presenting

Elective compulsory module: Isotope Geology

  • Isotope Geology I lecture
  • Isotope Geology I practice class

Elective compulsory module: Geostatistics 2 and applied numerics

  • Practice class: Geostatistics and applied numerics
  • Geostatistics seminar

Compulsory module: Paleoclimate

  • Lecture series: Paleoclimatology/Climate archives
  • Institute Seminar
  • Seminar: Data analysis and presentation
  • Paleoclimate project work

Elective compulsory module: Special Isotope Geology

  • Special Isotope Geology seminar
  • Project work: Special Isotope Geology
  • Field practice class Spain
  • Project seminar: Instrumental analytics