TY - JOUR

T1 - Boron and Lithium in Calcium Sulfate Veins

T2 - Tracking Precipitation of Diagenetic Materials in Vera Rubin Ridge, Gale Crater

AU - Das, D.

AU - Gasda, Patrick J.

AU - Wiens, R. C.

AU - Berlo, K.

AU - Leveille, R. J.

AU - Frydenvang, J.

AU - Mangold, N.

AU - Kronyak, R. E.

AU - Schwenzer, S. P.

AU - Forni, O.

AU - Cousin, A.

AU - Maurice, S.

AU - Gasnault, O.

PY - 2020

Y1 - 2020

N2 - The NASA Curiosity rover's ChemCam instrument suite has detected boron in calcium-sulfate-filled fractures throughout the sedimentary strata of Gale crater including Vera Rubin ridge. The presence of elevated B concentration provides insights into Martian subsurface aqueous processes. In this study we extend the data set of B in Ca-sulfate veins across Gale crater, comparing the detection frequency and relative abundances with Li. We report 33 new detections of B within veins analyzed between Sols 1548 and 2311 where detections increase in Pettegrove Point and Jura members, which form Vera Rubin ridge. The presence of B and Li in the Ca-sulfate veins is possibly due to dissolution of preexisting B in clays of the bedrock by acids or neutral water and redistribution of the elements into the veins. Elevated frequency of B detection in veins of Gale crater correlates with presence of dehydration features such as desiccation cracks, altered clay minerals and detections of evaporites such as Mg-sulfates and chloride salts in the host rocks. The increased observations of B also coincide with decreased Li concentration in the veins (average Li concentration of veins drops by ~15 ppm). Boron and Li have varying solubilities, and Li does not form salts as readily upon dehydration as B, causing it to remain in the solution. So the weak negative correlation between B and Li may reflect the crystallization sequence during dehydration on Vera Rubin ridge.

AB - The NASA Curiosity rover's ChemCam instrument suite has detected boron in calcium-sulfate-filled fractures throughout the sedimentary strata of Gale crater including Vera Rubin ridge. The presence of elevated B concentration provides insights into Martian subsurface aqueous processes. In this study we extend the data set of B in Ca-sulfate veins across Gale crater, comparing the detection frequency and relative abundances with Li. We report 33 new detections of B within veins analyzed between Sols 1548 and 2311 where detections increase in Pettegrove Point and Jura members, which form Vera Rubin ridge. The presence of B and Li in the Ca-sulfate veins is possibly due to dissolution of preexisting B in clays of the bedrock by acids or neutral water and redistribution of the elements into the veins. Elevated frequency of B detection in veins of Gale crater correlates with presence of dehydration features such as desiccation cracks, altered clay minerals and detections of evaporites such as Mg-sulfates and chloride salts in the host rocks. The increased observations of B also coincide with decreased Li concentration in the veins (average Li concentration of veins drops by ~15 ppm). Boron and Li have varying solubilities, and Li does not form salts as readily upon dehydration as B, causing it to remain in the solution. So the weak negative correlation between B and Li may reflect the crystallization sequence during dehydration on Vera Rubin ridge.

KW - boron

KW - ChemCam

KW - Curiosity

KW - Gale crater

KW - lithium

KW - VRR

U2 - 10.1029/2019JE006301

DO - 10.1029/2019JE006301

M3 - Journal article

AN - SCOPUS:85089847070

VL - 125

JO - Journal of Geophysical Research: Solid Earth

JF - Journal of Geophysical Research: Solid Earth

SN - 0148-0227

IS - 8

M1 - e2019JE006301

ER -