International audience; Jezero crater was chosen for exploration and sample collection by Perseverance due to its history as a lake with river deltas, its diverse mineralogy, including carbonates observed from orbit, and as a potential site to calibrate crater counting ages with radiometric dates of samples to be returned to Earth. This presentation focuses on the results of SuperCam, which uses LIBS for remote elemental chemistry, VISIR and remote Raman spectroscopy for mineral compositions and alteration, includes a microphone, and performs high-resolution imaging for textures and morphology. In the first year after landing, SuperCam and other instruments were used to explore Jezero’s floor. We found that all of the floor units are igneous, with lava flows comprising the upper units as part of the Máaz formation, while the lower formation, Séítah, is an olivine cumulate, produced by gravitational settling of olivine crystals in a large melt body. Artuby ridge, just outside the SW portion of Séítah and stratigraphically just above it, contains up to 60% pyroxene. The upper portions of the Máaz formation are more enriched in plagioclase, with the uppermost Ch’al member having the most evolved composition, along with the Content member, pitted rocks directly overlying the main cumulate portion of Séítah. After exploring the floor, Perseverance drove to the delta formation and began a walk-about style of observations starting at Enchanted Lake, just below an arm of the delta formation, and then moving into Hawksbill Gap, climbing 18 m in elevation between Devil’s Tanyard, Sunset Hill, and Hogwallow flats. Delta compositions initially displayed higher phyllosilicate contents, identified by absorptions at 1.4, 1.9, and 2.3 µm, and by higher LIBS H peak areas. Farther up, compositions changed to sulfur-bearing in lower locations within the continuous fine-grained light-toned strata (e.g., Pignut Mountain, Sol 463) and carbonate-rich in upper strata. Veins were observed, consisting of Mg-Fe carbonate (Elder Ridge, Sol 459) and anhydrite (Reid’s Gap, Sol 466). The sulfates suggest precipitation of these salts at a later stage, as the lake was evaporating. Carbonates and sulfates in veins in different locations indicate that groundwater was active in the lithified sediments and had significantly different chemistry at different intervals.