Petroleum geology is an independent science that has evolved from oil and gas leakage, anti-line theory, trap theory, and petroleum sediment theory. Here, “petroleum sludge” refers to the accumulation of conventional oil and gas in a single trap with a uniform pressure system and oil and water contact. Conventional petroleum deposits are the material studied in conventional petroleum geology, and the main parameter is the trap. The main theoretical problems studied by conventional petroleum geologists can be divided into six areas. The main points are static configuration parameters and operations. Buoyancy is the dominant force in primary and secondary migration control factors and the high production model for unconventional oil and gas are reviewed. Unconventional oil and gas geological research has been developed from nanoporous observation to full quantitative volume characterization and three-dimensional pore structure characterization, from macroscopic examination an occurrence case study to discuss the evolution of a microscopic occurrence case, from differential pressure drive and preferential channel migration to staged accumulation and preferential migration, from source-controlled accumulation to coaccumulation it is controlled by source reservoir assembly and preservation conditions, from accumulation model to enrichment and high production model, revealing research progress and future directions for unconventional oil and gas geology. Challenges are presented in the geological theory of unconventional oil and gas.