If you are an experienced climber or hill-walker you do not need to read this section.
Boots: for Geology field excursions you really need strong hiking boots. Wellingtons and trainers are not really suitable. Light-weight fashion shoes are considered dangerous and students who arrive wearing them may be sent home.
Anorak: if at all possible you should wear a waterproof anorak with integral hood. This will help keep out the wind as well as the rain.
Waterproof overtrousers: normal trouses can become very cold when wet. Waterproof overtrousers keep out the rain and can make the difference between an unpleasant and miserable day.
Woolen hat and gloves: these items make a big difference to personal comfort. Try to obtain goods made from 100% wool as they are better than man-made fibres when wet. Fingerless gloves are helpful as you can write and manipulate instruments without taking them off.
Knapsack: you need one big enough to carry your lunch and all of your warm waterproof clothing on the day that turns out to be scorching hot.
Thermal underwear: it is generally considered best to wear several layers of thin clothing rather than few thick layers. M&S have sports underwear - long-johns and long-sleeved vests.