Geological Insights & Event News

Christine Smith Siddoway presents new U Pb detrital zircon data showing that the Tava sandstone dikes of the Colorado Front Range derive from Neoproterozoic (770–680 Ma) Rodinia strata, with DZ peaks matching Grenville and Colorado sources. The work constrains emplacement to Pennsylvanian or earlier and links the dikes to early movement on the ancestral Ute Pass fault. In his Prez Sez column, President Paul Spear describes Mancos concretions and thanks John Youle. Regional news includes the upcoming San Juan College Energy Conference and a part time Petroleum Geology teaching opportunity.

Estuarine sandstones in the Eubanks and Shuck pools have produced over 14 million barrels of oil and are now being assessed for CO₂ recovery. John Youle describes a narrow Mississippian incised valley up to 220' deep, filled by fluvial, salt marsh, tidal flat, and estuarine facies during transgression, with traps formed by stratigraphic pinchouts, Ouachita folding, and karst collapse. In his Prez Sez column, current president Paul Spear urges membership renewal, and previews Youle’s upcoming presentation, noting its parallels to the Burro Canyon IVF play.

Lillian D. Wakeley’s talk examines Mosul Dam, built on dissolving limestone, marl, and gypsum that require nonstop grouting to prevent failure. Her team’s 3D modeling showed a migrating dissolution front driven by structural dip, an anticline, and undersaturated reservoir water—issues highlighted again when ISIS briefly seized the dam. In his Prez Sez column, President Paul Spear reflects on career changes and shares classic quotes on risk, exploration, and innovation. We mourn the passing of longtime petroleum scout and member, Kevon Smith.