VESIcal Workshop at vVMSG2022

VESIcal is a new tool for calculating solubilities of CO2-H2O fluids/vapours in magmatic systems. It provides a powerful interface for many of the most frequently used solubility models, enabling the calculation of saturation pressures, degassing paths, and fluid/melt compositions. The tool leverages the power and flexibility of the python programming language, but most calculations require very little coding experience. In this short workshop we will introduce VESIcal, some of the solubility models that are built into it, and we will demonstrate how fast and easy it is to obtain results, even when using large datasets. 

Workshop Instructors: Simon Matthews (University of Iceland) & Penny Wieser (Oregon State University)

The workshop will take place on Wednesday 12th January 10:00-12:00 GMT on Zoom, as part of the virtual-VMSG meeting programme. Attendees will receive an email from the Geological Society of London with a link to the Zoom meeting. Following the meeting, all the workshop resources will be available at including links to the lectures and practical demonstrations.

To participate in the hands-on exercises, you do not need to install anything on your own computer. Instead, all the calculations are performed on a cloud computing server. The only thing you need to access the server is a modern web browser (I find Chrome offers the best performance, but other browsers should work just fine).

Workshop Prerequisites

None! Other than an interest in volatile solubility modelling. You do not need any prior experience with coding (in fact you don’t need this to use VESIcal at all), using computation servers, or anything technical beyond using a web browser. We will show you everything else, and we will be on hang to help you get started.

However, please follow the instructions below before the workshop, and ideally as possible.

Preparation Instructions

  1. Go to the server web address provided in the VMSG email from the Geological Society of London (coming on Friday). [Please, please, please do not share this address publicly, otherwise I will have to start manually approving access for each user. To use a long-lived and public version of the server see, but if you do get access to this public server please do not use it for the workshop.]
  2. You should see a screen with a large orange button in the middle that says “Sign in with GitLab”. Click this button.
  3. If you have a GitLab account already then you can proceed to sign in. If not, please follow the directions to create one, it is free.
  4. You should see a loading screen with a progress bar, and then eventually a screen titled “ENKI Server”. You may also get some warning messages appear- it is safe to dismiss these. On the welcome screen click “Close this screen”.
  5. You should now see a window with two panes, the larger (right-most) pane having “Launcher” written in the tab. It should look very similar to this screenshot:
If you do not see this, or you get stuck at any other step, please email me ( as soon as possible and we will solve the problem. If you do see this screen (or one very similar- workshop materials may appear on the left-hand side by the time you login) then congratulations! You may now log out (click File in the top left, then Logout from the menu that appears).

NOTE: We are providing access to the server in advance of the workshop so that you can check you can get access to it and solve any problems before the workshop starts. Please do not run calculations on here before the workshop. All computation time costs credits, and we have only a limited quantity available for the workshop. If you want to explore the ENKI-server before the workshop, see for more information. Any misuse of the server will result in you being banned from it

For more information about VESIcal…

For more information about VESIcal, see, or read the VESIcal papers here:

Janet Watson Meeting 2019: From core to atmosphere- Deep carbon

As part of the Year of Carbon, the Geological Society of London are hosting a meeting for Early Career Scientists centred around Deep Carbon. Together with Lotta Purkamo (St Andrews) I am chairing the meeting. The first two days of the meeting will consist of oral and poster presentations, and mentoring activities run by prominent senior Deep Carbon scientists. The final day of the meeting will be given over to workshops about the future of Deep Carbon research.

More info, registration, and information about abstract submission.

Goldschmidt 2018

I will be in Boston for the entire week of Goldschmidt.

On Friday morning I will present a talk about my new dataset of CO2 and trace element concentrations in Icelandic melt inclusions, and what this data implies about identifying CO2-rich mantle domains both in Iceland and globally.
02c 310 Friday 11:15-11:30 abstract

At the Monday poster session Helen Williams and I will present our new Fe-isotope analyses on material from Iceland, and how these observations may be reconciled in terms of magma oxidation state, mantle melting and melt transport processes.
02b board 6 Monday 17:15-19:15 abstract

Goldschmidt 2017

I will be attending the Goldschmidt meeting all week, and will talk about my work on mantle CO2 heterogeneity at 9am on Thursday.

The roles of Degassing and Mixing on Volatile-Trace Element Systematics: Implications for Global Carbon Budgets. (05g: Ampithéâtre Havane, Thursday 0900-0915).

Magma mixing has become an important process in understanding how the geochemical variability of primary mantle melts is expressed in erupted products. In this talk I will argue that mixing has been under appreciated in the interpretation of the datasets that underpin our understanding of CO2-distribution in the mantle, I will use a combination of simple models, existing datasets and new melt inclusion data from Iceland.