Hi Huseyin,

It really comes down to what you are trying to do. I looked at both methods for my project on trace element geochemistry to characterise magmatic processes and fractionation trends. I ended up going with the LA-ICP-MS as the EPMA simply wouldn't be able to detect things like trace Nb-Ta in a rutile for example.

Both methods can do similar things, however, given that EPMA is a SEM based method, there are a number of additional analysis you can do that might be of interest.

It seems your interest is quite broad and so you might want to consider a combination of methods if that is an available option.

I've provided a brief summary below.

Hope this helps.

Zeb

EPMA:

- better accuracy

- better resolution

- versitile - can be combined with other detectors to provide a variety of data (back-scatter electron images, cathodoluminescence, SWIR)

-good quality control (QC) - lots of available standards and literature to support

- Can be time consuming

- Most EPMA's are typically 'tuned' to provide high quality results for certain parts of the periodic table. Can sometimes be limited by the number and type of monochromators used in the machine.

- more sample prep required (high quality polished surfaces)

- poor detection limits on trace element concentrations

LA-ICP-MS

- better detection limits for trace element concentrations

- faster

- less accurate

- QC issues - lack of reliable standards and converting CPS to ppm is somewhat of a dark art

First of all, I want to thank Eron and Zeb for their valuable contributions.

After a literature review and Eron's answer, I decided to use LA-ICP-MS for U-Pb dating and begin to pick zircon grains for it.

As Zeb's suggested, I had been decided to use both techniques but if it could possible to make only specific LA-ICP-MS analyses related to my research I was wanting to go toward that way.

Today after a face to face discussions with my colleagues I am much more clear about that LA-ICP-MS is the best way for my research. Because for some reasons I need depth profile analyses for some minerals.

But there is only one last question in my mind. I have some molybdenite samples and I am wondering is it possible to apply Re-Os isotope dating technique with LA-ICP-MS or should I have to use EPMA for accurate results.

Hi Huseyin,

It looks like as of 2019 someone has published a method on using the laser ablation method and applying the Re-Os dating of molybdenite. I've pasted the link below and it actually takes you to an article here on research gate. Best of luck!

Article First in situ Re-Os dating of molybdenite by LA-ICP-MS/MS

Hi Caleb,

That was the only missing part of the LA-ICP-MS technique for my research of interest. Sometimes we can miss out on very basic things because we did not focus enough on our requirements. Thank you for your contribution.

Best wishes.