July 2026 Bulletin Issue
ISBN: 9780891810896
128 pages

GEOLOGIC NOTE
The geological record is compelling; the Gulf Coast (southern United States) is experiencing a reversal from coastal stability and growth during the past few thousand years to rapid inundation and erosion during the last 150 yr. Indeed, coastal change is occurring faster than expected. This paper details the causes of this change and the efforts to combat it.

ARTICLES
Unconventional reservoirs have received attention for their potential to fulfill energy supply, requiring techniques like hydraulic fracturing to enhance production. In Argentina’s Neuquén Basin, the Agrio Formation has recently emerged as a promising unconventional play due to its similarities with Vaca Muerta Formation, the primary source rock. This study focuses on deposits of the lower Pilmatué Member, characterized by mudrock successions accumulated during transgressive periods, recognized as source rocks with three potential intervals.

The timing and origin of fluid activity are crucial for understanding the relationship between hydrocarbon accumulation and tectonic events. The authors conducted an integrated analysis combining petrography, geochemistry, fluid inclusion analysis, and laser ablation–sector field–inductively coupled plasma–mass spectrometry U-Pb geochronology of multiphase calcite veins collected from the Triassic Qinglong Formation carbonate reservoir in the Huangqiao area of the Subei Basin.

The middle Cretaceous (Albian) Mauddud Formation is a complexly layered limestone reservoir of approximately 117-m thickness in the Raudhatain and Sabiriyah fields, Kuwait. This paper reports on the results of a major proprietary reservoir characterization study carried out to provide input for building reservoir models, but has broader significance for understanding the impact on reservoir quality of depositional environments, cemented nodules, sequence stratigraphy, and the preservation of crestal porosity by oil in many other microporous limestone reservoirs.