Fault-fracture zones are regarded as key areas for oil and gas accumulation in tight sandstone reservoirs, owing to their connectivity and storage capabilities. The scale and genesis of these zones, as well as the development, distribution, and spatial configuration of fracture units, need to be accurately identified and described for effective exploration and development of tight and low-permeability reservoirs. However, existing data concerning fault-fracture reservoirs is often based on empirical judgments and qualitative descriptions of fault structures, and refined, structured quantitative characterizations are lacking. Such limitations have considerably restricted the precision of three-dimensional reservoir modeling and the forecasting of oil and gas migration and accumulation laws. The geological outcrops of fault-fracture reservoirs, particularly the Triassic Yanchang Formation outcrops in the southern Ordos Basin, were selected as research objects. Fracture units on outcrop profiles were meticulously characterized and classified into different fracture belts based on geological principles, and various fracture sections were identified. Subsequently, a software system for a geological knowledge base was designed and developed to achieve efficient organization and management of geological knowledge regarding fault-fracture reservoirs. Through practical testing, the developed knowledge base system was shown to efficiently manage geological interpretation results of fault-fracture reservoir outcrops, considerably improving the efficiency of querying, filtering, and statistical analysis of fracture units, thus providing a powerful tool to support reservoir modeling and prediction in fault-fracture reservoirs.