Maracaibo Continued: Generation and Migration of Hydrocarbons, Revisited after 42 Years (1984–2026)

In 1984 a team at Intevep, Venezuela's national petroleum research centre, set out to show how the Upper Cretaceous La Luna Formation charged one of the world's richest oil provinces. The result, Talukdar, Gallango and Chin-A-Lien (1986) in Organic Geochemistry 10, restored original organic richness to 2.5–10.8 wt% TOC, placed the onset and peak of oil generation at Lopatin TTI 10 and 35, proposed overpressure-driven microfracture expulsion at 30–50% efficiency and separated marine, terrestrial and mixed oil families (Elsevier record). Forty-two years later the paper has 97 citations in OpenAlex, the highest count among the Maracaibo petroleum-system and geochemistry papers checked for this edition. This continuation tests that framework against every primary source it could reach. It finds that the 1986 timing, the two-pulse charge history and the source attribution have survived kinetic modelling (1990, 1995), the AAPG petroleum-system synthesis (1994), the 2006 basin overview, a 2020 diamondoid study and a 2022 field-scale model. It then adds four quantitative results. The published 2.50 × 1014 kg of generated hydrocarbons demands a basin-average transformation ratio of about 0.85 over the whole 47,500 km² La Luna–Misoa footprint, or at least 40,160 km² of fully converted source at 65 m net thickness. The legacy specific yield of 290 MMbbl/km³ and the 1994 mass are reconciled by one decomposition: richness 1.59×, conversion 1.40× and initial HI 0.93×. The 2026 oil-in-place inventory of 270 to more than 329 Bbbl, converted to mass, implies that oil alone now represents 15–20% of the generated mass, against the 14% accumulation efficiency published in 1993. Cumulative production of more than 40 Bbbl equals about 2.3% of all hydrocarbons the La Luna ever generated in this system. Each section closes with a Socratic test, and Section 12 lists the observations that would falsify the reconstruction. Revision 1.0, 2 November 2026. Continuation of Talukdar, Gallango and Chin-A-Lien (1986), Organic Geochemistry 10, 261–279 (10.1016/0146-6380(86)90028-8). Includes the Intevep molecular lineage (Cassani, Bristol PhD 1985, with G. Eglinton), the Querecual–Orinoco system, Andean exhumation (Bermúdez 2009), and the ODP Leg 207 and Guyana–Suriname theses on the ACT and Aptian–Albian source rocks. Files: essay PDF, GLIAGoGRAPH cover, eight GLIAG-original figures and the companion Python charge-ledger script that reproduces every number in Section 6. © 2026 Marcel P.T. Chin-A-Lien, CC BY-NC-ND 4.0. Text and data mining reserved under Article 4(3) of Directive (EU) 2019/790.