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Geology topics

Maria-Paz Zorzano

Publications and source records attributed to Maria-Paz Zorzano.

3 recordsLinked to original sources

Sample Science Traceability Matrix (SSTM) for Perseverance’s Mars sample return collection

The Mars Sample Return (MSR) Campaign aims to retrieve a set of carefully selected and documented samples collected by NASA’s Perseverance rover in and around Jezero Crater on Mars and deliver this set to Earth for comprehensive laboratory analyses. To emphasize the immense scientific return of this unique collection, this work presents a Sample Science Traceability Matrix (SSTM), a systematic framework that aligns each sample with the MSR campaign’s defined science objectives, subobjectives, and critical research questions. The SSTM explicitly connects prioritized goals—including geologic history, astrobiology, planetary evolution, and human exploration science—to each of the individual samples gathered in and around Jezero Crater on Mars. This matrix offers a structured, quantitative method to assess each sample’s capacity to address key scientific questions, while highlighting synergies across the sample suite and showcasing the overall value of the collection. The SSTM provides a valuable tool for guiding future sample analyses and identifying the most impactful samples that could be collected in the future to complete the set collected by the Mars 2020 mission. It also supports the next phase of Mars sample science and informs strategies for future Mars exploration missions.

Astrobiology

Report of the Science Community Workshop on the proposed First Sample Depot for the Mars Sample Return Campaign

The Mars 2020/Mars Sample Return (MSR) Sample Depot Science Community Workshop was held on September 28 and 30, 2022, to assess the Scientifically-Return Worthy (SRW) value of the full collection of samples acquired by the rover Perseverance at Jezero Crater, and of a proposed subset of samples to be left as a First Depot at a location within Jezero Crater called Three Forks. The primary outcome of the workshop was that the community is in consensus on the following statement: The proposed set of ten sample tubes that includes seven rock samples, one regolith sample, one atmospheric sample, and one witness tube constitutes a SRW collection that: (1) represents the diversity of the explored region around the landing site, (2) covers partially or fully, in a balanced way, all of the International MSR Objectives and Samples Team scientific objectives that are applicable to Jezero Crater, and (3) the analyses of samples in this First Depot on Earth would be of fundamental importance, providing a substantial improvement in our understanding of Mars. At the conclusion of the meeting, there was overall community support for forming the First Depot as described at the workshop and placing it at the Three Forks site. The community also recognized that the diversity of the Rover Cache (the sample collection that remains on the rover after placing the First Depot) will significantly improve with the samples that are planned to be obtained in the future by the Perseverance rover and that the Rover Cache is the primary target for MSR to return to Earth.

Meteoritics and Planetary Science

Regolith of the crater floor units, Jezero crater, Mars: Textures, composition and implications for provenance

A multi-instrument study of the regolith of Jezero crater floor units by the Perseverance rover has identified three types of regolith: fine-grained, coarse-grained, and mixed-type. Mastcam-Z, WATSON, and SuperCam RMI were used to characterize regolith texture, particle size, and roundedness where possible. Mastcam-Z multispectral and SuperCam LIBS data were used to constrain the composition of the regolith types. Fine-grained regolith is found surrounding bedrock and boulders, comprising bedforms, and accumulating on top of rocks in erosional depressions. Spectral and chemical data show it is compositionally consistent with pyroxene and a ferric-oxide phase. Coarse-grained regolith consists of 1-2 mm well-sorted gray grains that are found concentrated around the base of boulders and bedrock, and armoring bedforms. Its chemistry and spectra indicate it is olivine-bearing, and spatial distribution and roundedness indicate it has been transported, likely by saltation-induced creep. Coarse grains share similarities with the olivine grains observed in the Séítah formation bedrock, making that unit a possible source for these grains. Mixed-type regolith contains fine- and coarse-grained regolith components and larger rock fragments. The rock fragments are texturally and spectrally similar to bedrock within the Máaz and Séítah formations, indicating origins by erosion from those units, although they could also be a lag deposit from erosion of an overlying unit. The fine- and coarse-grained types are compared to their counterparts at other landing sites to inform global, regional, and local inputs to regolith formation within Jezero crater. The regolith characterization presented here informs regolith sampling efforts underway by Perseverance.

JGR-Planets