Volcanic minerals, carbonates and clay minerals are observed both in the delta and elsewhere in the crater. Some carbonates (limestones) are thought to have been formed directly in the lake. Such lake carbonates, and especially the clay minerals, indicate freshwater conditions and have the potential to preserve traces of life.

However, other types of minerals, such as sulphates that contain iron oxide, amorphous silicon oxides, and hydroxides, have also been observed; these tend to form in acidic waters that gradually dried up. These minerals indicate that the environmental conditions in Jezero Crater became drier and less conducive to life at a later stage. However, even among these minerals there are some in which biosignatures can be very well preserved.

Studying rocks and minerals with a wide origin – whether formed by volcanic activity, by water, or modified in giant impact events – will provide important insights into the history of Mars.