LIBS for Elemental Analysis in Field Geochemistry - An Interview with Andrew Somers

Interview conducted by Will SoutterSep 29 2014

In this interview, Andrew Somers from SciAps talks about the benefits of their range of LIBS field-portable analyzers for geochemical applications.

What are the main requirements for handheld elemental analyzers in geochemical applications that differ from other fields?

Geological materials can have an incredibly diverse range of possible chemistry. Many other fields that also employ the use of elemental analysis such as positive material identification [PMI] of alloys deal with homogenous and often quite similar chemistry within sample sets.

With field portable elemental analysers used for geochemical applications, the range of elements that can be analysed is therefore incredibly important due to the range of possibilities that may be encountered even when dealing with spatially related sample sets.

The ability to test all of the major rock forming elements as well as many trace elements is beneficial to allow identification of rock types and to improve understanding of their formation and what changes that may have occurred to them since formation.

The testing of geological materials with field portable analyzers is often carried out in the field or in the harsh conditions of an operating mine so a high degree of ruggedization is highly advantageous.

The speed of acquisition is also an important feature with regards to throughput and being able to incorporate the analytical program into existing workflows related to activities such as drilling, mining and processing.

The SciAps Z range of handheld LIBS analysers are built to be used in harsh environments

How does Laser-Induced Breakdown Spectroscopy fit these requirements?

LIBS can test a very broad selection of minerals including major and trace elements, which has not been possible with existing field portable analytical techniques.

Most notably, very light elements such as Li, C, B, and Na can be measured with LIBS but not XRF, and LIBS also gives improved detection limits for light elements such as Mg, Al and Si.

What features and capabilities of the SciAps Z make it especially suited for geochem applications?

AS: The SciAps Z range of handheld LIBS analysers are highly ruggedized and built to be used in the harsh environments that geoscientists often work in. The detector systems are well protected behind a solid aperture window, and are of a more durable type than conventional field portable analytical devices.

The high quality display is larger and easier to see and operate than existing hand held analyzers used in this field. The devices utilises an Android operating system with an app-based user interface, which users may well be familiar with from smartphones, and the device has excellent connectivity options to other industry standard software packages used for storage, processing and visualisation.

The SciAps Z can measure very light elements such as Li, C, B, and Na, and offer improved detection over XRF for Mg, Al and Si.

Why is elemental analysis such a crucial part of geochemical exploration?

Elemental analysis is one of the main pillars of Geochemistry. Analytical techniques such as XRF and ICP-MS have been the main lab-based approaches to elemental analysis in the last few decades.

Much work has been done to establish effective use of elemental data, especially using indexes to classify rock types and understand changes in the rocks related to metamorphism.

More recently, field portable analytical methods such as handheld XRF have allowed geologists to carry out elemental geochemistry in the field, although limitations on the analysis of the lightest major elements including Mg, Al and Si and the inability to measure Na have restricted the extent that traditional lab based approaches could be applied using field generated data.

LIBS opens up many new opportunities in this area. For example, LIBS can be used to select appropriate samples in the field, to optimize and inform the analysis performed in conventional laboratory analytical programs. It can also be used to rapidly identify samples which may need special treatment.

What other products does SciAps supply that are useful in geochemistry and mineralogy?

SciAps offers a complimentary range of field portable mineralogical testing devices - the Navigator NIR, and both the ReporteR and Inspector Raman spectrum analysers.

These two different types of spectroscopy can assist identification of different types of minerals. While there are some materials which can be identified with both methods, some minerals can be identified with NIR but not with Raman and vice versa.

Being able to utilise mineralogical data in combination with the elemental capabilities of the LIBS analyser allows geoscientists to cross validate their analytical data and strengthen their interpretation of the data, which can certainly be very beneficial.

LIBS can be used to rapidly identify samples which may need special treatment

How has the response to the Z been from your existing customers in the industry?

The response has been overwhelming. People have heard about LIBS, but most were not aware it was possible to build a handheld device like this.

Geoscientists are really excited to hear that they can now analyse important elements that they were unable to do in the field before. We have a lot of people wanting to test their samples with the LIBS – at this stage we are really just trying to keep up with the demand!

How does SciAps plan to expand their reach in the geochem market in the near future?

We are currently launching our range of products suited to the geochemistry and mineralogy markets at a range of different conferences and conventions around the world. We are generating data to show just what we can do on a range of geological applications and engaging with peak research organisations to see just how far we can take this exciting new product.

About Andrew Somers

Andrew Somers is an Australian earth and environmental scientist with a trans-disciplinary academic background. His employment history ranges from working with Rio Tinto Exploration as a graduate geologist to recent and current roles involved in product development for, and sales to, the global exploration and mining industry.

Andrew has acted in the past as an expert technical representative with regards to mining for global market leaders in the manufacture and development of FPXRF technology. In addition to FPXRF he has also worked with field portable XRD and NIR Spectrometers.

Andrew is currently looking at new technologies with the potential to integrate with existing field portable analytical systems to develop new approaches of technological based mineral exploration, mining, mineral processing and other natural resources focused applications.