“Who am I – how I got there”
18th October 2013
My research focuses on the deep
interior of the Earth, and, in
particular, the inner core.
The Earth has several layers: below the very thin crust is a solid mantle made of
rock, then, about half way down, a liquid outer core made of predominantly iron
and finally a solid inner core also made predominantly of iron. I spend most of my
time trying to work out the properties of core forming materials (iron alloyed with
nickel and some light elements) in order to understand the structure, dynamics
and evolution of our planet
I apply this research to other terrestrial planetary cores, such as Mars and
Mercury, and also to the interiors of the icy moons of the gas giants.
On Earth, the processes occurring in the core maintain our magnetic field and
supply heat to the mantle which aids convection which in turn drives plate tectonics
The only way to directly sample the Earth's deep interior is with seismic waves
generated after earthquakes. These compressional (P) and shear (S) waves travel
throughout the Earth, including through the core. Their velocities are related to
the elastic properties of the material through which they travel.
The Inner Core from Seismology
Sun & Song 2008
Inner core may be layered
Using these waves, seismologists tell us that the Earth's inner core the planet…
Evolution of is much more
complex than one might think, being layered and anisotropic. The anisotropy is
such that P-waves travel faster N-S than they do across the equator.
The density if the inner core is significantly greater than the average density of the
Earth and this, together with information from cosmochemistry and meteorites, tells
us that the core is made predominantly of iron with about 10% nickel and a few
percent light elements such as silicon and sulphur.
Computational Mineral Physics
• Calculate properties of iron and
iron alloys at atomistic level
• The bonding is described by
quantum mechanics; calculate
the energetics of the system.
• Match calculated properties with
the actual observations from
• Gives composition, structure and
dynamics of the Earth’s core
My research is to calculate the properties of iron and I do this using quantum
mechanical codes running on national supercomputers.
Simulation at 3,600,000 atm and 6000 K
Materials are simulated on the computer by putting atoms in a box and seeing how they
respond to changes in pressure and temperature. These calculations are not so straightforward
when you consider that the Earth's core reaches 3.6 million atmospheres and around 6000K.
However esoteric the research,
it would appear that iron in the
Earth's inner core still catches
the attention of some journals.
Indeed, even Hollywood has jumped on the bandwagon
Recently a major motion picture …
…….sadly the producers conclude……..
They should have studied Geophysics not French Literature!!
Unfortunately a lot of that film is scientifically inaccurate!
In my everyday life at UCL I divide my time between a number of activities……
How I got this job:
Degree in Physics and Astronomy
PhD in Geophysics
Royal Society University Research Fellowship
(~ 5th Fellowship attempt over 2 years – very important to nurture good referees)
Now: Professor of Mineral Physics at UCL
First ever female professor in Earth Sciences at UCL
Normally run <5 PhD students and postdocs + others
The turning point for my career was the Royal Society URF - it secured my job.
At some point in your career you might have some of these
My first child….
Fortunately I have childcare once a week - and he causes a stir at the school gate.
In the early days I took my children everywhere - on field trips with undergraduates, and even
to a conference where the father chaired the session holding the baby while I was speaking !
It is very important for me to keep active and
have other interests - of which I have many! I
try and do something for myself every day, if
only for 10 minutes. And, although most of
my house is a bit of a tip, I have a place that
is mine that I can retreat to.
You may think you are not good enough - this is perfectly normal
Always ask questions – however stupid – (but maybe not in public?)
Find yourself a mentor with whom you feel totally comfortable
Get yourself out there – meet people, play pool, stay up late etc.
Show kindness and respect to students and staff
Take every opportunity – if you are anxious about it, then definitely do it
Get as much childcare and/or domestic help as you can afford
Spend 15 minutes a day tidying/organising one area/thing
Insist on a weekly “date night” with husband/partner
Have other interests, exercise and switch off when you can
There is no such thing as perfect balance – do what you can and don’t worry
1940s advice on how to handle women employees
1. Pick young married women. They have more sense than the unmarried.
2. When you do have to use older women, get ones who have worked
outside the home.
3. Retain a physician and give each girl a special physical examination –
this reveals whether they have any female weaknesses that would make
her mentally or physically unfit for the job.
4. Give them a definite daylong schedule of duties so that they will keep
busy without bothering the management for instructions every few
minutes. They lack initiative in finding work themselves.
5. Give them an adequate number of rest periods. You have to make some
allowances for feminine psychology. They need to keep their hair tidied,
apply fresh lipstick and wash their hands several times a day.
6. They are very sensitive so be tactful when issuing instructions.
7. Get enough size variety in uniforms so that each girl can have a proper
fit. This point cannot be stressed too much in keeping women happy.