Delta Layers
Contributed by Sarah Fagents
This high resolution enhanced color Mastcam-Z camera mosaic was acquired on Sol 24, and shows the eroded front of the delta that formed at the western side of Jezero Crater early during Mars’ history. Jezero once held a lake, and sediments transported into the lake from the watershed in the west would have been deposited as the incoming river met the still waters of the lake. The portion of the delta in the mid-field rises more than 75 meters (roughly 250 feet) above the crater floor. Although the outcrops visible here are more than 2 km (1¼ miles) away from the rover, we can easily see the details of layering within the deposits. Towards the top of the delta we see mainly horizontal layers, whereas towards the center of the image the beds are dipping down to the right. The observed layering could represent many pulses of sediment deposition over a long period. The composition and fine-scale structure of the deposits, once we measure them, could contain information on the surrounding watershed and the lake environment at the time of deposition. Beyond the delta deposits, we see the rim of Jezero crater rising up in the distance. I particularly like this image because I feel the delta beckoning us closer to decipher the history of Jezero’s watery past and to seek evidence of microorganisms that could once have inhabited the crater lake.
March 15, 2021