Geochemistry

Geotechnical engineering

Petroleum engineering

Anesthesia

Geology

Groundwater

Organic chemistry

Caprock

Medicine

Chemistry

Saline

Carbon dioxide

Aquifer

Carbon sequestration

The Journal of Supercritical Fluids

The long-term CO2 storage in deep saline aquifers mainly depends on the performance of caprock. However, one of the major concerns with deep saline CO2 sequestration at geological time scales is the back-migration of injected CO2 through the caprock due to chemico-mineralogical variations with time. Several studies, including geo-chemical models and laboratory tests, have investigated the behaviours of caprock in the presence of CO2. This paper reviews laboratory and numerical studies of the geo-chemical properties of caprock, highlights the gaps in research and provides suggestions for future research on caprock characteristics in deep saline aquifers after CO2 injection. Accordingly, a significant attention should be paid on potential field scale caprock reactivity in long term scale associated with geological CO2 sequestration.

Understanding the chemico-mineralogical changes of caprock sealing in deep saline CO2 sequestration environments: A review study