Daño de formación en la cara de la fractura Implicancias en rocas tight, Cuenca del Golfo San Jorge
Ofeliz, Silvia Iovine, Gastón
Daño de formación en la cara de la fractura Implicancias en rocas tight, Cuenca del Golfo San Jorge - 8 p. ; 109-117
Formation damage generates important deterioration in the petrophysical properties of the reservoirs. The case of this study corresponds to a well in the province of Santa Cruz, Argentina, with productions much lower than expected, coming from tight reservoirs (K <0,1 mD). To evaluate the presence of damage, a new laboratory technique was applied to simulate a hydraulic frac stage during which the gelled fluid for frac remained in contact with the reservoir for more than thirty days. Samples of a core were analyzed by physical measurements, thin sections and scanning with the electronic microscopy before and after immersing the samples in the frac fluid under reservoir conditions and for a period of twenty days. The lithologies analyzed were fine tuffs, tobaceous sandstones and very fine tuffs and in all three there was evidence of formation damage. Zeolites and chlorites were the minerals most susceptible to alteration with the frac gelled fluid and the main damage mechanisms were the physical and chemical alteration of zeolites and the loss of crystallinity in chlorites, in both cases with possible formation of residues obstructing the limited permeable throats of tight reservoirs.
Daño de formación
Rocas tight
068.82 553.28 C62 2018 0015648
Daño de formación en la cara de la fractura Implicancias en rocas tight, Cuenca del Golfo San Jorge - 8 p. ; 109-117
Formation damage generates important deterioration in the petrophysical properties of the reservoirs. The case of this study corresponds to a well in the province of Santa Cruz, Argentina, with productions much lower than expected, coming from tight reservoirs (K <0,1 mD). To evaluate the presence of damage, a new laboratory technique was applied to simulate a hydraulic frac stage during which the gelled fluid for frac remained in contact with the reservoir for more than thirty days. Samples of a core were analyzed by physical measurements, thin sections and scanning with the electronic microscopy before and after immersing the samples in the frac fluid under reservoir conditions and for a period of twenty days. The lithologies analyzed were fine tuffs, tobaceous sandstones and very fine tuffs and in all three there was evidence of formation damage. Zeolites and chlorites were the minerals most susceptible to alteration with the frac gelled fluid and the main damage mechanisms were the physical and chemical alteration of zeolites and the loss of crystallinity in chlorites, in both cases with possible formation of residues obstructing the limited permeable throats of tight reservoirs.
Daño de formación
Rocas tight
068.82 553.28 C62 2018 0015648
