My Geology Note-blog

A chronicle of my PhD journey and other geology writings

Month: Nov, 2014

Edible geology #1 – The Earth is like a peach… sort of

As I wrote the title of this post I was reminded of a quotation from the Quandary Phase of The Hitch-hiker’s guide to the Galaxy: 

“Life… is like a grapefruit. Well, it’s sort of orangey-yellow and dimpled on the outside, wet and squidgy in the middle. It’s got pips inside, too. Oh, and some people have half a one for breakfast.” – Ford Prefect

We could probably mull over how serious Douglas Adams was being when he gave that line to Ford but food analogies are a common metaphor, and geology abounds with them. So here’s a simple one to start of with:

The Earth is like a peach.

The similarities

The ratio of skin to flesh to stone is very similar to the ratio of crust to mantle to core (more anon on that!)

The fuzzy exterior of a peach at that scale represents quite nicely the hills and valleys of the planet, as does the non-perfect spherical shape. (The Earth is not actually a sphere but bulges slightly at the equator).

The differences

The crust of the Earth is broken into tectonic plates not one perfect, connected skin.

The flesh of a peach doesn’t illustrate well the plastic, solid-yet-it-flows, fluidity of the mantle (even if you wait until the peach is so soft the juice goes everywhere!)

The stone, while a good rough analogue for the diameter of the core, doesn’t illustrate that the core is made up of a liquid outer and solid inner core.

It also doesn’t show the correct temperature, pressure and phase boundaries but then that’s just splitting hairs. What can someone really expect for comparing fruit to the entire Earth!

So there we go, next like you eat a delicious peach you can contemplate its beautiful similarity to the layers inside the Earth.



“MY LIT REVIEW IS GOING FINE! STOP BOTHERING ME!!!!… ahem… I mean, my lit review is going fine, why do you ask?” (current word count: approximately 1700 words… ~1000 of which are references… oh dear…)


For more info and further food based Earth analogies including boiled eggs and onions: 

Day in the life of a PhD student: as told through PhD comics

Are you sitting comfortably? Then we’ll begin…

To do my bit to slow climate change caused by anthropogenic carbon dioxide I have been cycling to the department on dry days. However, you have to get there early otherwise:


Then it’s off to the office:


In answer to the above: the X-ray imaging lab, not something I’m going to share on the internet, Engineering (2nd supervisor), Geography (1st supervisor), Tephra Group, Geography dept., I don’t take classes, geology and yeah, I’m all over the place.

In the corner of the office exists something not too dis-similar to this, only with more outdoor coats thrown into the mix:


After checking emails and doing some reading it’s off to the lab. When I get there I like to check on the fish tank:


(This is incorrect, we actually don’t have any fish left, they died so now all we have are shrimp, hermit crabs and water snails).

Recently I’ve been getting trained up on the X-ray tomography:


In truth it’s been fun learning how to use the equipment, it certainly teaches you patience!

Speaking of lab equipment, we might give names to the fish tank residence (such as Hermit Crab, other Hermit Crab, Big Snail etc etc) but we don’t go this far:



Sometimes I have demonstrating where I help in practical classes:

phd082510sDuring demonstrating it usually falls into the blue and red categories as to why we wear lab coats. It’s never too cold in the practical labs… quite to opposite. 60 plus students in a confined space for two lots of 2 hours will do that.

At the moment writing my literature review feels a bit like this:


(500 words a day and I’ll have a draft by Christmas… current count: 448, woops)

I’ve yet to experience academic auto-pilot… but give me time!

phd091014sAt the end of to day some networking is required and I vainly attempt to do some Science Communication:


I did say “attempt”!


Bonus round: