I really wanted to know whether people were inspired by science teachers at school, geography classes, TV documentaries, or just by a desire to learn more about our incredible planet. And I also wanted to know how many people came to Earth Sciences late (like me), having their heads turned away from the subject they intended to study whilst at University.
The response to my tweet has already been fantastic... had racked up about 100 uses on twitter by the time I started to collate the results here on Saturday evening.
So here are all the responses to date. I've tried to organise them.... some responses fit in multiple categories.
Obviously this is by no means a scientific or rigorous survey of all the reasons that people ended up studying Earth Sciences, notably because the geo-twitterati are by their very nature the most enthusiastic and evangelical about their subject, and also because my tweet has probably reached those who remained in academia preferentially to those that had careers in industry. Nevertheless, I think they make a pretty interesting collection.
Also bear in mind this caution from Sara Mynott: