GFZ German research centre for geo sciences

Section 3.3: Earth Surface Geochemistry

HELGES | Helmholtz Laboratory for the Geochemistry of the Earth Surface

The HELGES lab building finished in August 2013 and now more than 200 m² of lab space is available for sample preparation and measurements of cosmogenic nuclides (10Be and 26Al) and stable isotopes of metals and metalloids (currently Li, Mg, Si, Fe, Sr, B) in geological and environmental sample materials, such as sediments, rocks, river water, soils, vegetation.

Two clean labs, class 1000+, with class 10 laminar flow workstations, are available for sample preparation of low concentration samples to avoid contamination in order to obtain accurate measurements. In addition to the clean labs, additional dry and wet chemistry labs provide the necessary equipment for preparation of solid and liquid samples, such as rock crushing, sieving, mineral separation, filtration of water samples, microwave assisted sample dissolution, microscopy and sample preparation for micro-analytical work by laser ablation.

The HELGES lab also accommodates analytical instruments for concentration and isotope ratio measurements on liquid and solid samples. A Thermo Neptune Multicollector Inductively Coupled Plasma Mass Spectrometer (MC-ICP-MS) is used for isotope measurements (Li, Mg, Si, Fe, Sr, B). Concentration measurements are done by Inductively Coupled Plasma Optical Emission Spectrometry (Varian 720 ES ICP-OES). Both ICP instruments can be coupled to an in-house built femtosecond laser ablation system (fsLA-MC-ICP-MS or fsLA-ICP-OES) for in-situ concentration and isotope ratio measurements at the micrometer scale. Nearly all work conducted in the GermanResearchCentre (GFZ) HELGES lab falls into one of two categories: (1) approved collaborative projects that will lead to publications in international scientific journals, and (2) research projects within the GermanResearchCentre (GFZ) Earth Surface Geochemistry group, including development and improvement of analytical methods.

Laboratories

Cosmo Lab

Clean Laboratory for Cosmogenic Nuclides

In our clean room laboratory for cosmogenic nuclides, we prepare approx. 250 samples per year, mainly for beryllium-10 (¹⁰Be). Applications of in situ ¹⁰Be in quartz make up a smaller part of this. Meteoric ¹⁰Be is becoming more and more popular!

Sample Preparation Laboratory

Sample Preparation Laboratories

These laboratories allow the preparation of samples, such as drying, wet or dry sieving, magnetic separation, separation by means of color differences (“mineral sorter”), chemical separation steps (mainly used for quartz purification - e.g. by feldspar flotation with dodecylamine, with ortho-phosphoric acid, ultrasonic baths/hotdog rollers with weak hydrofluoric acid), as well as filtration, weighing, melting, dilution, etc.

Instruments

Laser Ablation

UV Femtosecond Laser Ablation

With the ultrashort laser pulse length and UV range laser to achieve high-resolution in-situ micro-scale analyses of both isotope ratios and element concentrations.

Neptune

Neptune | Multicollector ICP-MS

The capacity to monitor up to nine isotope beams simultaneously at variable mass-resolution means the Neptune can yield highly precise isotope ratios for metals and metalloids across the whole periodic table.

Element2

Element 2 | High Resolution ICP-MS

With high sensitivity, large dynamic range and the capacity to resolve out molecular interferences, the Element 2 is well-suited to determine trace element concentrations in challenging matrices.

iCap

iCAP Q | Quadrupole ICP-MS

The iCAP Q can scan rapidly across multiple masses in a single analysis, and is equipped with a reaction cell to reduce polyatomic interferences, making it a workhorse for low-level element concentration analysis.

Spectro

Spectro & Varian | ICP-OES

Depending on the composition of the samples, the ICP-OES from Spectro or the ICP-OES from Varian can be used to determine main and trace elements. The “Spectro” allows exceptional sensitivity and a high possible matrix load (e.g. salt samples) due to its radial plasma view as well as the DualSideOn interface and argon humidifier. The “Varian” has a better detection limit for many elements due to its axial plasma view.

Microwave

Sample Digestion System

(Almost) all types of sample material can be digested with the Multiwave at high pressures and high temperatures - with low blank values at the same time.

Iridium

Iridium Strip Heater

One of four worldwide iridium-strip-heater is located in our laboratory to create homogeneous glasses out of powder with short time and high temperature impact (~2000 °C).

back to top of main content