UTJECAJ DEPRESIJE NA PRITOK VODE U BUŠOTINE U KARBONATNIM PODINAMA KARPATSKOGA PREDGORJA NA JUGOISTOKU POLJSKE

This paper presents an analysis of well testing data, performed with a Drill stem test (DST). The carbonate levels of Mesozoic reservoir rocks were investigated in the research area of the Carpathian Foredeep. Based on the results of 17 two-cycle DST reservoir tests, the dependence of the volume of the reservoir water flow rate from the Mesozoic carbonate reservoirs (Upper Jurassic, Lower Cretaceous) to the wells as a function of the mean depression of bottom pressure was researched in the selected oil exploration area in the Carpathian Foredeep basement, SE Poland. Using methods of statistical analysis, a satisfactory correlation between variables for power and the exponential model was found, and a weak correlation for the linear model was found. A decrease in the value of the reservoir water flow rate along with an increase in pressure depression was found for the Mesozoic carbonate reservoirs, which may indicate the occurrence of fractures and micro-fractures shortening under extreme pressure depression and blockage phenomena of fractures and cavernous pores in the perimeter area by solid particles (cuttings, salt, polymers, etc.).U radu je prikazana analiza rezultata testiranja bušotina metodom DST-a (engl. skr. od Drill Stem Testing). Istraživanjem su obuhvaćene razine karbonata u stijenama mezozojskih ležišta u Karpatskome predgorju. Na temelju sedamnaest testova ispitivanja ležišta metodom DST-a, provođenih u dvama ciklusima, istražena je ovisnost volumena protoka vode iz mezozojskih karbonatnih ležišta (gornja jura i donja kreda) u bušotine, a kao funkcija prosječne depresije zbog tlaka na dnu bušotine. Kao objekti istraživanja odabrani su oni smješteni upravo u naftnoj zoni Karpatskoga predgorja, na jugoistoku Poljske. Na temelju statističke analize uočena je zadovoljavajuća korelacija između varijabli potencijskoga i eksponencijalnoga modela te slaba korelacija kod linearnoga modela. Smanjenje pritoka ležišne vode iz mezozojskih karbonatnih ležišta, uz povećanje depresije, potencijalno upućuje na pojavu smanjivanja pukotina i mikropukotina uslijed prevelike depresije te na začepljivanje fraktura i šupljina nastalih otapanjem, do čega dolazi zbog krutih čestica poput krhotina, soli, polimera itd