1. C. Viviano-Beck, A. Brown, E. Amador, J. Mustard, and K. Cannon NOTE ADDED BY JPL WEBMASTER: This content has not been approved or adopted by, NASA, JPL, or the California Institute of Technology. This document is being made available for information purposes only, and any views and opinions expressed herein do not necessarily state or reflect those of NASA, JPL, or the California Institute of Technology.

2.  South of the “Nili Fossae Trough” site  Within Mars 2020 elevation constraints  Stratigraphy similar to that exposed in the north; includes strong carbonate signature  Cache significantly diverse material that is in-place (known context)

3.  Elevation: Relatively low slope to drive out of trough and access phyllosilicates and plateau

4.  MOLA slope: 0 5 10 15 20 25°

6. MAF  CRISM (FRT & HRL)  HiRISE

7. MAF Olivine (OLINDEX3) LCP (LCPINDEX2) HCP (HCPINDEX2) Evolving primary compositions? Land-on unaltered volcanic Hesperian plains (age-dating)

8. MAF OLINDEX3 LCPINDEX2 HCPINDEX2 IR Albedo R1330

9. NE

10. BD1900R2 D2300 BD1400 OLINDEX3 LCPINDEX2 HCPINDEX2

11.  Fan?/debris flow? 300 m ESP_016496_2000

12.  Fan?/debris flow? 300 m ESP_016496_2000

13.  Land-on in place unaltered volcanic Hesperian plains (age-dating)  Hesperian flow characteristics (magmatic evolution of Syrtis Major through mineralogic/elemental analysis, flow layers/thickness with GPR)  Ancient Noachian LCP-bearing material (ancient crust composition, mineralogic/elemental analysis)  Determine composition of Noachian alteration material (constrain alteration temperature, fluid composition, pH, etc.)

14. NE Alteration Unaltered Exposed contact between altered and unaltered material

15. IR Albedo PFM R1330 BD2355 D2300 BD2290 OLINDEX3 BD1900R2 D2300 BD1900R2 D2300 BD1400

16. Laboratory Reflectance BD1900R2 D2300 BD1400

17. BD1900R2 D2300 BD1400  Hydration variability?  2.39 µm variability  Possible carbonate component

18.  Mg-OH bearing layered material below plateau 150 m ESP_016496_2000 BD1900R2 D2300 BD1400

19.  Mg-OH bearing layered material below plateau BD1900R2 D2300 BD1400 50 m

20.  Mg-OH bearing mega-breccia 100 m ESP_016496_2000 BD1900R2 D2300 BD1400

21.  Discernable contact between unaltered and altered Noachian material (test formation hypotheses)  Compositional stratigraphy of altered material, carbonate component? (diverse alteration conditions, temperature/pH/fluid gradients > energy gradient)  Hydration state of phyllosilicates (human resource)  Layered alteration material at the top of the stack (sedimentary? changing formation mechanism?)  Possibility of mega-breccia provides even more potential diversity  Contact between Syrtis flows and plateau material - nature of Fossae faulting (GPR)

22. IR Albedo R1330 MIN2295_2489 MIN2345_2537 D2300 Carbonate abundance (CO 2 sequestration/cycling)

23. IR Albedo R1330 BD2165 BD2190 MIN2200 Pedogenesis?

24. BD1900R2 D2300 BD1400  Erosionally-resistant fracture fill 50 m ESP_016496_2000

25.  In place Noachian LCP-bearing material (ancient crust composition, mineralogic/elemental analysis)  Variety of alteration conditions (hydrothermal fluid, mineralization along fractures)  Olivine-carbonate(-talc?) assemblage (test talc hypothesis: increased Si activity may help preserve biosignature-silicification, exothermic long-lived rxn)  Kaolinite-bearing material may record pedogenic sequence

28. Altered/LCP flow Olivine and LCP-rich material HCP flow

29. Carbonate Fractures Layers Kaolinite Compositional stratigraphy

30. Debris flow/fan Phyllo. Strat. Phyllo. layers Olivine- carbonate Kaolinite Fractures