Open AccessDissolution of arkose under conditions relevant to deep reservoirs: the effect of organic acid on the porosity and pore size distribution of arkose
Author(s) -
Chen Zhang,
Yuanju Li,
Kefei Chen,
Shixin Zhou,
Jing Li,
Pengpeng Li,
Zexiang Sun,
Bingkun Meng,
Deliang Fu
Publication year - 2020
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/600/1/012047
Subject(s) - porosity , dissolution , permeability (electromagnetism) , clastic rock , saturation (graph theory) , mineralogy , organic acid , effective porosity , organic matter , geology , chemistry , structural basin , geomorphology , geotechnical engineering , organic chemistry , biochemistry , mathematics , combinatorics , membrane
The organic acid is important in forming secondary pores and enhancing total porosity of the clastic rock. But there is little study to investigate the effect of organic acid on the porosity distribution of clastic rock from deep reservoirs. The changes in porosity, permeability, and porosity distribution of the dissolved medium-grained lithic arkose, from Yanchang Formation in Ordos Basin, were examined by nuclear magnetic resonance (NMR). The results show that porosity and permeability of rock increase with the time of exposure of the rock to the organic acid solution and it increases rapidly in the early period, then slightly increases to a saturation level. Besides, organic acid mainly changes the frequency and the shapes of T2 distribution in NMR analysis, and this study suggests that organic acid has more effect on rocks with larger pore throat than those with smaller pore throat.