Post

Key Takeaways

• Posted prices for crude oil were the primary mechanism for international oil pricing for over 50 years, and their replacement by market-based pricing fundamentally changed the economics of oil production worldwide — from the 1920s through the 1970s, the major integrated oil companies posted the prices they would pay for crude oil produced in countries where they operated, with these prices forming the basis for royalty and tax calculations owed to host governments; the posted price was typically set below actual market value (because the majors both produced and sold the oil, they benefited from a low posted price that reduced their royalty obligations), creating chronic tension between the producing countries and the international oil companies; when OPEC nations began acquiring ownership stakes in their oil resources in the late 1960s and early 1970s, the ability to unilaterally set posted prices followed, and the 1973 Arab oil embargo demonstrated that posted prices were now set by producers rather than buyers; today, crude oil prices are determined by continuous trading on futures exchanges (NYMEX for WTI, ICE for Brent), with physical crude trades priced at a differential to these benchmark futures prices; posted prices in the traditional sense still exist in some limited domestic markets (certain US inland crude buyers post daily prices at pipeline terminals) but are no longer the dominant global pricing mechanism.
• Rig structural posts must be engineered to handle combined loading from hook load, wind, seismic acceleration, and equipment weight without buckling, and their design is governed by API Specification 4F for drilling and well servicing structures — a land drilling rig rated for 1,000,000 pounds hook load has derrick posts that must carry axial compression (from the drill string weight) combined with bending (from wind loading and off-center hook loads), and the post geometry, wall thickness, steel grade, and connection design are calculated for the maximum design load case with appropriate safety factors; offshore jackup rig leg posts face additional cyclic loading from waves and platform motion that is not present in land rig design; the post-to-base connection at the rig substructure is a critical weld joint that must carry the full derrick load in shear and bending, and this connection is subject to periodic inspection (visual, magnetic particle, or ultrasonic testing) to detect fatigue cracks before they propagate to failure; derrick rating in pounds of hook load is the parameter that determines what string weights and casing programs a rig can handle, and the structural posts are what physically implement that rating.
• Post-drill analysis refers to the systematic comparison of pre-drill predictions against actual drilling results, and it is one of the most valuable but most consistently underperformed activities in exploration and production — before a well is drilled, the geologist predicts the formation tops, reservoir quality, fluid contacts, and hydrocarbon volumes; the drilling engineer predicts pore pressures, formation strength, and drilling performance; the completion engineer predicts the stimulation response; post-drill analysis compares each prediction to the actual result and documents the prediction error, its magnitude, direction, and probable cause; when post-drill analysis is done systematically across multiple wells in a basin, it identifies systematic prediction biases that can be corrected in future wells — for example, if post-drill analysis shows that pore pressure is consistently overpredicted in a specific formation, the pre-drill model calibration is adjusted; if reservoir quality is consistently overestimated, the seismic attribute calibration is reviewed; the value of this learning only accrues if the analysis is done rigorously and honestly, which requires a culture that treats prediction errors as learning opportunities rather than failures to be concealed.
• Post-stimulation evaluation determines whether a hydraulic fracture or acid stimulation treatment achieved its design objectives, and it drives the completion optimization learning that improves future well designs — immediately after a stimulation treatment, the well is put on flowback and the rate, pressure, and produced fluid composition are monitored; post-stimulation pressure transient analysis (a flow period followed by a shut-in) reveals the effective fracture half-length, fracture conductivity, and post-stimulation skin compared to the pre-stimulation baseline; if the post-stimulation skin is significantly better than predicted (lower than expected), the treatment design achieved better results than modeled and future designs can be optimized for cost; if the post-stimulation performance is worse than predicted (fracture length shorter than designed, conductivity lower than modeled), the causes are investigated — were there near-wellbore tortuosity issues? Was proppant transported effectively? Did the fracture height grow out of zone? — and the learning is applied to the next completion; in unconventional plays where hundreds of wells are completed in similar formations, systematic post-stimulation analysis using production data analytics (decline curve analysis, EUR estimation, pressure response diagnostics) has driven dramatic improvements in completion design efficiency over time.
• Post-salt formations represent some of the world's largest undeveloped deepwater oil provinces, and their geological characteristics create specific drilling and production engineering challenges distinct from pre-salt and sub-salt targets — post-salt sedimentary sequences were deposited above evaporite salt formations (the Aptian salt in the South Atlantic, the Zechstein salt in the North Sea, the Louann salt in the Gulf of Mexico) and are characterized by complex deformation from halokinesis (the salt flowing plastically under overburden pressure), creating salt diapirs, salt canopies, and minibasins in the post-salt section above the salt; in the Santos and Campos basins of Brazil, post-salt carbonate reservoirs above the famous pre-salt reservoirs were the primary production targets for decades before the ultra-deep pre-salt discoveries; in the North Sea, post-Zechstein Triassic and Jurassic sandstones are the classic reservoirs of the established fields; post-salt drilling is generally less technically challenging than drilling through salt and into pre-salt formations (which involves extreme temperatures, pressures, and wellbore stability challenges), but the structural complexity caused by salt movement requires careful seismic interpretation and well path design to navigate between salt bodies and reach the intended reservoir.