Feldspars are a common framework grain in sandstone reservoirs targeted for carbon capture and storage (CCS). They are mechanically weak under reservoir conditions and are very likely to react with CO2 injected into saline aquifers or depleted hydrocarbon reservoirs.  Reactions could dissolve feldspar and precipitate new minerals to an extent that fundamentally changes reservoir properties and potentially mineralises injected CO2. The current general consensus is that these features are unlikely to impact…