Geology is not just an academic study of earth, its rocks and their processes of formation (See Wikipedia Geology) but is a very practical undertaking pursued by professional mineral explorer or surveyor and amateur fossicker alike. There are a few basic tools that are common to geological exploration.
Maps and Survey Books
Maps are very useful for locating sites of interest whether it is a fossicking site or a must see ancient geological formation, a fossil or an intriguing mineral deposit. Pocket geological maps and books are especially useful being portable and often vital for locating sites of geological interest. Compass or GPS can assist with finding particular locations.
The most common general purpose hand tools used in field geology include rock picks, hammers, hand trowels and chisels. A rock pick of about 16 inches gives good leverage for rock sampling, while small 2 to 4 pound hammers will assist with cracking rocks. Hand trowels are valuable for moving surface soils, shifting small debris and digging. A set of chisels can also be useful making possible a range of fine shaving and splitting operations. When rock splitting is proposed protective goggles can be useful and gloves are often a must for protecting the hands. Common equipment in gold prospecting will include some sieves and pans that are suitable for sifting small gold flecks from alluvial sands.
When obtaining rock samples some sampling bags are useful, zip locked plastic bags are useful for small samples although heavy weight cloth bags will be necessary for larger rocks that can be heavy and easily split plastic bags. Consider a jar for collecting samples like opal, which is a strone that can benefit from being soaked in water which reveals its colours and helps make it stronger so it is less likely to fracture.
Hand magnifying lenses will help identification tasks in the field including looking at fossils or inspecting rocks for minerals, while at home a mineral identification kit (see PIRSA's Mineral Kit) are also a useful piece of equipment that can help identify rocks according to properties like softness and whether they are metallic.
A camera is a vital tool to record information found at geological sites - especially small fossils that should not be moved and large formations that cannot be moved. Tape measures will help record the size of rocks and fossils that may be of interest later, while a note book and pen can be valuable. If you are in a wet location consider the waterproof notepad that can withstand rain (see for example The Geology Store).
Many of these common pieces of equipment can be found in general purpose "student starter packs" that can be purchased at geological suppliers (see Geology Student Pack) or kits can be assembled according to specific needs. More experienced geologists undertaking mapping and surveying or soil sampling will need special equipment that is not likely to be found in these common packs.