WJEC Geology GL5 Natural Resources — Resource Booklets & Data Materials

Ore deposit maps in these booklets typically show the spatial relationship between mineralisation and geological features such as intrusions, faults, and host rock contacts. Before answering questions, identify the geological controls on mineralisation: is the deposit concentrated along a contact (skarn), in a vein system (hydrothermal), or disseminated through altered rock (porphyry)? Petroleum cross-sections require you to identify the five elements of a petroleum system within the diagram. Trace the source rock, migration pathway, reservoir, seal, and trap. Note whether the trap is structural (anticlinal or fault-bounded) or stratigraphic (pinch-out, unconformity), and assess whether the seal is likely to maintain integrity. Borehole log data presents lithological, geophysical, and sometimes geochemical information at depth. Practise correlating logs from multiple boreholes to reconstruct the subsurface geology, identify the top of the reservoir unit, and estimate reservoir thickness and lateral extent.