Basin-Scale Hydraulic Evaluation of Groundwater Flow Controlled Biogenic Gas Migration and Accumulation in the Central Pannonian Basin

Abstract

Biogenic or microbial methane has an increasing share in the global gas resource base, though its exploration still faces challenges and welcomes innovations. Critical elements of its migration and accumulation models are the groundwater flows which gather and transport the gas in aqueous solution, and the seal rocks or aquifers which lead groundwater flows horizontally over great distances. This paper intends to introduce the hydraulic trap concept into these models, which is able to drive fluids horizontally without an overlying seal rock. Since hydraulic traps can evolve as a result of the interplay of regional groundwater flow systems, the basin-scale hydraulic evaluation methodology which was developed for the analysis of these systems was further improved by this study to focus on their interplay. The improved methodology was applied on measured hydraulic data in a study area in the Central Pannonian Basin (Hungary) around the Hajdúszoboszló gas field where as a result, the first groundwater flow controlled dissolved biogenic gas migration and accumulation model could be set up. In addition, the proposed methodology can be used in any terrestrial sedimentary basin, and in particular, where topography-driven flow systems are underlaid by an abnormal pressure regime.

Wetland Management in Recharge Regions of Regional Groundwater Flow Systems with Water Shortage, Nyírség Region, Hungary

“…The areas are located on the southern border of the regional recharge area in the Nyírség region, where, at shallow depths (>500 m), flow-through starts to occur and become more dominant towards SW, followed by discharge conditions more to the south. This finding is consistent with the results of Szabó [39] and Czauner et al [58], who showed recharge-flow-through conditions at a shallow depth (>500 m) in the South-Nyírség region and discharge conditions to the south of the study area. Szanyi [45] also obtained similar results, showing that original flow-through existed in the South-Nyírség region, but the large water exploitation around Debrecen (a town near the study area, Figure 1b) changed the conditions to mainly recharge-dominated.…”

“…It appears as a transient zone first, represented by the near-hydrostatic upwelling water of the dissipated overpressure regime on the p(z) plot, as well as on the cross-section. This transient zone was identified in other parts of the Great Hungarian Plain, too [58,59]. Real overpressure values occur only at ~−2000 mBf, representing the upward-directed overpressured flow regime.…”

Nem lehet mindenhol mindent, de mindenhol lehet valamit – A geotermikus energia hasznosításának lehetőségei a hazai ellátás diverzifikálása érdekében

“…) mellett a közel hidrosztatikus nyomásviszonyok. A megújulás mértékének és pontos tartományának hidraulikai megértése azonban további kutatásokat igényel (Czauner et al 2023). Ezzel szemben a mélyebb túlnyomásos tározókba a csapadékvíz semmiképpen nem tud természetes úton bejutni, így azokról feltételezhetjük, hogy nem megújuló vizet tartalmaznak (Mádl-Szőnyi-Simon 2016; Mádlné Szőnyi,…”