I couldn't find anything on the geology course when I was applying last year so hopefully this is helpful!
I'm currently studying Geology at Durham and have just finished my first term there, so far I've been enjoying the course, all the lecturers are very good. There's loads of people doing an Earth science subject but actually doing Geology is quite small, I know of about 10 including me but there's probably more so modules which are more specific to Geology have a much smaller class size to other modules.
Nightlife in Durham is pretty good, it depends on what you want, the most popular nightclub called Jimmy's closes about 2am, the same with many of the other nightclubs nearby, however Newcastle is a really short train journey away so you could get that if you wanted more clubs. So far I've had no problem with all the clubs and late night takeaway pizza does the job after. Most of the nightclubs are in the centre of the town so if you're in a college on the bailey like me then going out is easy.
The lifestyle is also whatever you choose as long as you make sure to go to the lectures, for Geology you have one 3 hour lecture per module a week and you have 6 modules, with the time in between you can do whatever you want, so far there hasn't been much coursework or exams to revise for so meeting up with friends is mainly what I'm doing.
If you have any questions about the course, the colleges (I'm at castle college) or about Durham let me know.