If you had asked 16 year old me what I was going to study at uni I would have replied "Geography!". Same with 15 year old me, 14 year old me and 13 year old me, that was always the plan. However there was one fundamental flaw: I really didn't like the human side. Don't get me wrong, I can see how its all very interesting but I was a girl who liked maps and rocks, I got excited by long-shore drift and went through a phase where if you asked me what my favourite thing in the world was I would have told you it was a wave-cut platform. So yes, I loved geography but I didn't love all of it. Geology seemed to be the degree of me! I have ended up studying Earth Sciences which is definitely a good choice on my behalf but it took a lot of research to find it. Geology, Geophysics, Geoscience, Earth Science, Physical Geography; these are all courses I looked at and was confused by the difference. So here's what they are so you don't have to spend hours trawling the internet like I did!
Photo of a cliff face of Triassic sandstones taken on a field trip to Dorset illustrating some examples of cross bedding.
Physical Geography:
This is the most straight forward as its probably what you studied in school. Physical geography is the side of geography that deals with the natural world and processes as well the impact humans have had on it. Think longshore drift, volcanoes, the water cycle, rainforests, things like that. Physical geography can be a fascinating subject for learning about the world around us and how humans interact with it. It includes the study of the atmosphere, biosphere, hydrosphere and geosphere as well as mostly likely lots of field trips. Physical geography will often be studied within a wider geography course.
Geology:
Geology, in simple terms, is the study of rocks. It deals with the earth's physical structure, processes and history. Geologist study different rock types - sedimentary, igneous and metamorphic - as well as things such as seismology, volcanology and paleontology. Geology is a nice broad undergraduate course in the geosciences giving you a strong background knowledge which you can specialise with later.
Geophysics:
Geophysics is taking physics and applying it to the Earth such as looking at its internal structure. Geophysics involves a lot of maths, seismology, structural geology and data handling. Geophysics is often studied as part of a geology or earth science course and is something you will specialise in later if, unlike me, you decide you really like maths and coding.
Geosciences/Earth Science:
Geoscience and Earth Science are kind of the broad term for the study of the Earth and are umbrella terms for the other things mentioned on this page. A course in either of these will primarily be a geology course combined with aspects of oceanography and climate science as well as the other fundamental sciences (chemistry, physics, biology) you need to know to understand them.
Environmental sciences:
Environmental (geo)science deals with the study of the environment including its deterioration and mitigation techniques. Degrees often follow a similar structure to Earth Science courses, giving you a solid background in Earth Science skills and concepts in the first years before allowing you to specialise later on. Examples of modules in environmental science courses may include looking at pollutants, resource distribution and management as well as range of laboratory and field work.
Paleontology:
Paleontology is primarily the study of fossils. This doesn't tend to be offered at undergraduate level but will be an aspect of most (if not all) geology and earth science degrees. Paleontology involves looking at fossils and using them to interpret the environment a rock may have been deposited in, looking at evolutionary history and learning about past ecosystems.
Moral of the story - research is key. When deciding what you want to do look at university websites and see what modules each course offers. Different terms can be used in different places for things that are very similar and some courses with the same name may cover different aspects of the subject. For example, at Oxford if you are on the Earth Science course you can do four years and graduate with a master in Earth Science or chose to stop after three and get a bachelors in Geology even though you will have studied the same course for the first three years.