# Eoin Mac Craith Marine Geologist

Name?
Eoin MacCraith
Job Title?
Marine Geologist
Using different types of sonar to create 3D maps of the seafloor, along with shallow cross-sections of the sediment beneath.
• Analysing and processing the data.
• Mapping and reporting on navigation hazards to the UK Hydrographic Office, who are responsible for nautical charts in Ireland.
• Shipwreck mapping.
• Installing tide gauges and GPS stations around the country to support the marine survey work.
• Crewing small, inshore survey craft. The boats are so small that the scientists are also the crew!
How do you use mathematics in your job?
Sometimes I need to manipulate data into different formats so that it can be processed – I write short pieces of code in Microsoft Excel to achieve this, which requires the use of basic mathematical formulae.
While working offshore on small survey vessels, I sometimes find myself having to work out quick calculations on pieces of paper using various formulae – the most common one is determining the density of the vessel’s sonar pings on the seafloor. These are simple formulae that take in variables such as vessel speed and sonar ping rate.
In general the work is highly numeric – while not usually requiring complex manual calculation on the part of the user, there are large amounts of numeric data to be handled and interpreted.
The concepts behind the work that we do – be it geodetic surveying, processing of bathymetric data, processing of navigational data – involve complex mathematics. Though we do not carry out the calculations ourselves, it helps to have some understanding of what’s taking place when we operate the equipment and the different software packages.
The analytical end of the work does involve a lot of plotting of numeric data, in the form of scatter plots, linear plots etc. Sometimes we use mathematics to determine trends in the data. Again most of this is done in Microsoft Excel. We do a lot of analysis of tide data using such methods.
What type of mathematics do you use to solve problems?

Often it’s just basic subtraction, division and multiplication, but being done on the fly in tricky environments. We use a lot of technology but now and again it’s good to quality control the results with your own brain.
Apart from that, I use a lot of software that itself makes use of very complex mathematics  – I’m still in the process of learning what exactly is happening inside the black box when I push the button!
What aspects of the mathematics curriculum or mathematics courses have proven most useful to you?

Applied mathematics has been particularly useful, as it prepares you for the use of mathematics to solve real-world problems. That being said, the entire curriculum is important as it de-mystifies a lot of concepts that can underlie the way different types of software packages work.
Statistics is another important element of maths, for many kinds of scientific work. A good understanding of statistics can help to open a lot of doors. Personally I’ve often found it to be one of my shortcomings and wish I had spent more time on it.
What is your education to date?

In university I studied Physics, Maths and Geology, with my final Bachelor of Science degree focusing on Geology. Following this I did a masters in Oceanography.
I started off with highly mathematical subjects and then gradually departed that end of things and moved more towards studying and interpreting the physical environment through observation. When I started working in the commercial world after finishing my masters, the requirement for mathematical and technical thinking came rushing back in.