Earth Sciences

Lectures

Earth Sciences is often treated as ‘the third option’ to fill in your choices, but many enjoy the course so much that they choose to abandon their previous plans and continue Earth Sciences in later years. The course itself covers a very wide range of subjects, including volcanics, palaeobiology, climate, sedimentary processes, the geological history of Britain and ‘Exoplanet Sciences’. It prepares keen Earth Scientists with a wide knowledge base to grow from, while supplying interested students with a solid grounding in an interesting field. By the end of IA Earth Sciences, you will be able to look at rocks and deduce their geological histories, to notice and describe fossils in the stone of your college and to realise the continental collisions that happened beneath your very feet: hopefully you will be a little more in tune with the inorganic natural world around you, and maybe even the worlds above. The lecturers are often very information-dense and can move fairly quickly, leaving you a little confused at the end of the hour. Notes are often distributed at the start of each lecture and vary between reading like a textbook and having only diagrams. They keep you on your toes for sure. On the whole though, they are well-detailed in the important concepts and often contain references to extra material (which are helpful for essay plans and general understanding). The lectures are not recorded, so I would recommend paying attention, particularly as the pace can be rapid and/or uneven. Reading through notes after each lecture is a good idea, as it is for every subject, and make sure to bring up any points of confusion with your supervisors. The lecture series titles are listed below: Michaelmas:

Introduction to the Earth
What are Plates?
Earth’s Climate System
What’s the Earth Made Of? An Introduction to Rocks and Minerals
Earth and Other Planets

Lent:

From Minerals to Rocks: How the Crust Works
Palaeobiology
Sedimentary Processes and Products
Introduction to Arran

Easter:

Britain’s Geology: Solving the Jigsaw
Geology Beyond the Solar System
Planet Earth: the Bigger Picture

Supervisions

Supervision work is varied: essays, short answer questions, rock and fossil identification and description, and map exercises. Essays and short answer questions will look to cover recently lectured material to check understanding of concepts and to prepare for the written theory exam. Rock and fossil identification and description will prepare you for the practical exam and help put some theoretical knowledge into a more tangible context. Map exercises similarly prepare for the practical exam and can help put theoretical knowledge into a wider context. In the supervisions themselves, you will often simply go over your work, some other exercises (e.g. more maps or fossils) and any difficult topics in the lectures.

Practicals

The practicals are not assessed but it is worth staying there the whole time (you can leave when you want) and making sure you understand things as there is a practical exam at the end of the year. If you cannot come to your assigned slot for whatever reason, you may turn up to another one, but try to stick to your slot. Do not be scared if you find the first few weeks very confusing – there is a lot of new vocabulary and techniques to get used to, and you will definitely get more confident throughout the year. Ask the demonstrators if you do not understand anything! Many of them are PhD students or younger and so sympathise with whatever confusion you might be feeling. There is also a field trip. The Arran field trip was an amazing experience. Follow your demonstrators closely and pay attention to how they provide an interpretation of and insight into the various things you will see. As the field trip is held in the Easter break (March-May), you will have learned almost all of the year’s content. At Arran is where you will see many, if not all, of the theories you have learnt come to life, from volcanics to fossils, from tectonics and folding to sedimentary processes: many confusing things may become clear and click into place here. Highlights include walking through hundreds of millions of years in a day, finding fossilised footprints, touching the edge of a magma intrusion, standing on an ancient desert, staring at a flash flood and making a geological map in the field. Bring a lot of waterproofing: a reliably waterproof jacket, waterproof trousers/overalls, waterproof and grippy walking boots. For notetaking, you are provided with an A5 notebook; I preferred to use a journalist-style flip notepad, as it fit into my jacket pockets (a lot easier than wrestling it out of a plastic sachet in the wind and rain) and I found it easier to write in.

Revision

For the essays, attempt as many past essay questions as possible. First, you will get more skillful in writing, managing your time and drawing diagrams (draw large diagrams with scales and tables everywhere where possible, they love it). Second, you will see that the topics tend to be repetitive. You have to write 5 essays on the exam, if you are lucky and encounter familiar topics, that would save you loads of time since you do not need to come up with new ideas and structure. In terms of practicals, you can get the key to the Department for a £10 deposit to get in anytime. If the main gate to Downing Site is locked, use the gate at the junction of Tennis Court Road and Fitzwilliam Street. The lab has a humongous stock of rocks, minerals, fossils and thin sections with booklets containing their description. It is worth going through these several times to make sure you can identify and describe them quickly (aim for under 3-4 minutes). Also re-read through all your practical handouts during the Easter term, they sometimes contain pretty interesting and niche samples – the sort that examiners love to put in their questions. You will not understand all the concepts in Michaelmas but things will start to make sense after Lent and you will learn a lot more by looking back. Try to combine information on related topics, e.g. anything to do with geological history (palaeobiology, rock types in Arran, geological events in the UK, etc.). It will further help your understanding and remembering of certain topics that may seem abstract alone but work when with others. Definitely visit the Sedgwick Museum of Earth Sciences (and other Natural Sciences museums if you are keen) to do your revision there – it is particularly useful for palaeontology. They have rare examples of fossils that are tricky to identify (e.g. bivalves which look like ideal examples of brachiopods). Do not memorise all the samples, just focus on the different shapes and features. Maybe during the exam, you will recall seeing your sample in Bay 5 of the Museum and will be able to categorise it. Finally, remember to revise your Map notes and keep practising past year papers, including the map questions.

Exams

Be aware of format changes. As of 2018-19, the assessment is 40% Practicals and 60% Written Paper – each paper is 3hrs long. The practicals consist of 4 questions – rocks, thin sections, fossils and map, so spend no more than 45 minutes each. The written paper consists of one calculation question and 5 essay questions.

Useful resources

Sedgwick Museum of Earth Sciences
The lab’s stash of fossils, rocks and thin sections
Kearney, P., Klepeis, K. A. & Vine, F. J. (2009) Global Tectonics, 3rd ed. Hoboken: Wiley-Blackwell.
MacKenzie, W. S. & Guilford, C. (1980) Atlas of rock-forming minerals in thin section, 1st ed. Milton Park: Routledge.
Collinson, J & Mountney, N. (2019) Sedimentary Structures, 4th ed. Edinburgh: Dunedin Academic Press Ltd.
Any extra reading mentioned in lectures (I have not yet found any one textbook that covers all bases)