Wiens Roger C, Udry Arya, Beyssac Olivier, Quantin-Nataf Cathy, Mangold Nicolas, Cousin Agnès, Mandon Lucia, Bosak Tanja, Forni Olivier, McLennan Scott M, Sautter Violaine, Brown Adrian, Benzerara Karim, Johnson Jeffrey R, Mayhew Lisa, Maurice Sylvestre, Anderson Ryan B, Clegg Samuel M, Crumpler Larry, Gabriel Travis S J, Gasda Patrick, Hall James, Horgan Briony H N, Kah Linda, Legett Carey, Madariaga Juan Manuel, Meslin Pierre-Yves, Ollila Ann M, Poulet Francois, Royer Clement, Sharma Shiv K, Siljeström Sandra, Simon Justin I, Acosta-Maeda Tayro E, Alvarez-Llamas Cesar, Angel S Michael, Arana Gorka, Beck Pierre, Bernard Sylvain, Bertrand Tanguy, Bousquet Bruno, Castro Kepa, Chide Baptiste, Clavé Elise, Cloutis Ed, Connell Stephanie, Dehouck Erwin, Dromart Gilles, Fischer Woodward, Fouchet Thierry, Francis Raymond, Frydenvang Jens, Gasnault Olivier, Gibbons Erin, Gupta Sanjeev, Hausrath Elisabeth M, Jacob Xavier, Kalucha Hemani, Kelly Evan, Knutsen Elise, Lanza Nina, Laserna Javier, Lasue Jeremie, Le Mouélic Stéphane, Leveille Richard, Lopez Reyes Guillermo, Lorenz Ralph, Manrique Jose Antonio, Martinez-Frias Jesus, McConnochie Tim, Melikechi Noureddine, Mimoun David, Montmessin Franck, Moros Javier, Murdoch Naomi, Pilleri Paolo, Pilorget Cedric, Pinet Patrick, Rapin William, Rull Fernando, Schröder Susanne, Shuster David L, Smith Rebecca J, Stott Alexander E, Tarnas Jesse, Turenne Nathalie, Veneranda Marco, Vogt David S, Weiss Benjamin P, Willis Peter, Stack Kathryn M, Williford Kenneth H, Farley Kenneth A
Space and Planetary Exploration Team, Los Alamos National Laboratory, Los Alamos, NM, USA.
Department of Geoscience, University of Nevada Las Vegas, Las Vegas, NV, USA.
Sci Adv. 2022 Aug 26;8(34):eabo3399. doi: 10.1126/sciadv.abo3399. Epub 2022 Aug 25.
Before Perseverance, Jezero crater's floor was variably hypothesized to have a lacustrine, lava, volcanic airfall, or aeolian origin. SuperCam observations in the first 286 Mars days on Mars revealed a volcanic and intrusive terrain with compositional and density stratification. The dominant lithology along the traverse is basaltic, with plagioclase enrichment in stratigraphically higher locations. Stratigraphically lower, layered rocks are richer in normative pyroxene. The lowest observed unit has the highest inferred density and is olivine-rich with coarse (1.5 millimeters) euhedral, relatively unweathered grains, suggesting a cumulate origin. This is the first martian cumulate and shows similarities to martian meteorites, which also express olivine disequilibrium. Alteration materials including carbonates, sulfates, perchlorates, hydrated silicates, and iron oxides are pervasive but low in abundance, suggesting relatively brief lacustrine conditions. Orbital observations link the Jezero floor lithology to the broader Nili-Syrtis region, suggesting that density-driven compositional stratification is a regional characteristic.
在“毅力号”之前，耶泽罗撞击坑底部的成因曾有多种假设，包括湖泊成因、熔岩成因、火山空降成因或风成成因。“好奇号”火星车在火星上的前286个火星日进行的观测揭示了一个具有成分和密度分层的火山和侵入性地形。巡视路线沿线的主要岩性是玄武岩，在地层较高的位置斜长石富集。在地层较低的地方，层状岩石中标准辉石含量更高。观测到的最低单元具有最高的推断密度，富含橄榄石，有粗大（1.5毫米）的自形、相对未风化的颗粒，表明其成因是堆积岩。这是首个火星堆积岩，与火星陨石有相似之处，火星陨石也显示出橄榄石不平衡的特征。包括碳酸盐、硫酸盐、高氯酸盐、水合硅酸盐和氧化铁在内的蚀变物质普遍存在，但丰度较低，这表明湖泊环境相对短暂。轨道观测将耶泽罗撞击坑底部的岩性与更广阔的尼利-锡尔蒂斯地区联系起来，表明密度驱动的成分分层是一个区域特征。
