New Constraints on the Lunar Optical Space Weathering Rate

2021 ◽  
Author(s):  
C. J. Tai Udovicic ◽  
E. S. Costello ◽  
R. R. Ghent ◽  
C. S. Edwards
Keyword(s):  
Space Weathering ◽  
Weathering Rate

scholarly journals Redetermination of the space weathering rate using spectra of Iannini asteroid family members

Icarus ◽  
2008 ◽  
Vol 195 (2) ◽  
pp. 663-673 ◽  
Author(s):  
Mark Willman ◽  
Robert Jedicke ◽  
David Nesvorný ◽  
Nicholas Moskovitz ◽  
Željko Ivezić ◽  
...  
Keyword(s):  
Family Members ◽  
Space Weathering ◽  
Weathering Rate

Calcium Budgets for Catchments as Interpreted by Strontium Isotopes

1989 ◽  
Vol 20 (2) ◽  
pp. 85-96 ◽  
Author(s):  
Gunnar Jacks ◽  
Göran Åberg ◽  
P. Joseph Hamilton
Keyword(s):  
Steady State ◽  
Forest Ecosystem ◽  
Coniferous Forest ◽  
Strontium Isotopes ◽  
Runoff Water ◽  
Weathering Rate ◽  
Weathering Rates ◽  
Exchangeable Calcium

Strontium isotopes in precipitation, soil and runoff water can be used to establish a ratio of wet plus dry deposited Sr to Sr released by weathering. This ratio is especially enhanced in areas with old acid Proterozoic rocks (0.6-2.5 Ga) and Archean rocks (>2.5 Ga). Since Sr and Ca behave in an analogous way in the coniferous forest ecosystem the results for Sr can be used for the determination of Ca. If the deposition of calcium can be calculated reasonably accurately the weathering rate can also be estimated. Five catchments have been investigated using this approach. Three of them seem to be close to a steady state, wherein the losses and gains of calcium to the system are equal. In the two southern-most catchments there seems to be an ongoing loss of exchangeable calcium. The loss by runoff occurs with sulphate being the dominant anion. Weathering rates of 1.5 to 4.8 kg Ca/ha year have been estimated.

A MICROMETER THICK COATING LAYER SLOWING THE WEATHERING RATE OF GLACIAL POLISH

2017 ◽  
Author(s):  
Shalev Siman-Tov ◽  
◽  
Greg M. Stock ◽  
Emily E. Brodsky ◽  
Joseph Clancy White
Keyword(s):  
Coating Layer ◽  
Weathering Rate ◽  
Thick Coating

scholarly journals Coordinated analysis of space weathering characteristics in lunar samples to understand water distribution on the Moon

2021 ◽  
Vol 27 (S1) ◽  
pp. 2260-2262
Author(s):  
Alexander Kling ◽  
Michelle Thompson ◽  
Jennika Greer ◽  
Philipp Heck
Keyword(s):  
Water Distribution ◽  
Space Weathering ◽  
The Moon ◽  
Lunar Samples

scholarly journals Coordinated analyses on space weathering signatures on a Fe-sulfide grain from asteroid Itokawa

2021 ◽  
Vol 27 (S1) ◽  
pp. 2048-2051
Author(s):  
Laura Chaves ◽  
Michelle Thompson ◽  
Shoumya Shuvo
Keyword(s):  
Space Weathering

scholarly journals Current, steady-state and historical weathering rates of base cations at two forest sites in northern and southern Sweden: a comparison of three methods

2020 ◽  
Vol 17 (2) ◽  
pp. 281-304 ◽  
Author(s):  
Sophie Casetou-Gustafson ◽  
Harald Grip ◽  
Stephen Hillier ◽  
Sune Linder ◽  
Bengt A. Olsson ◽  
...  
Keyword(s):  
Steady State ◽  
Soil Depth ◽  
Base Cations ◽  
Base Cation ◽  
Mineral Weathering ◽  
Soil Horizon ◽  
Soil Horizons ◽  
Weathering Rate ◽  
Weathering Rates ◽  
Forest Sites

Abstract. Reliable and accurate methods for estimating soil mineral weathering rates are required tools in evaluating the sustainability of increased harvesting of forest biomass and assessments of critical loads of acidity. A variety of methods that differ in concept, temporal and spatial scale, and data requirements are available for measuring weathering rates. In this study, causes of discrepancies in weathering rates between methods were analysed and were classified as being either conceptual (inevitable) or random. The release rates of base cations (BCs; Ca, Mg, K, Na) by weathering were estimated in podzolised glacial tills at two experimental forest sites, Asa and Flakaliden, in southern and northern Sweden, respectively. Three different methods were used: (i) historical weathering since deglaciation estimated by the depletion method, using Zr as the assumed inert reference; (ii) steady-state weathering rate estimated with the PROFILE model, based on quantitative analysis of soil mineralogy; and (iii) BC budget at stand scale, using measured deposition, leaching and changes in base cation stocks in biomass and soil over a period of 12 years. In the 0–50 cm soil horizon historical weathering of BCs was 10.6 and 34.1 mmolc m−2 yr−1, at Asa and Flakaliden, respectively. Corresponding values of PROFILE weathering rates were 37.1 and 42.7 mmolc m−2 yr−1. The PROFILE results indicated that steady-state weathering rate increased with soil depth as a function of exposed mineral surface area, reaching a maximum rate at 80 cm (Asa) and 60 cm (Flakaliden). In contrast, the depletion method indicated that the largest postglacial losses were in upper soil horizons, particularly at Flakaliden. With the exception of Mg and Ca in shallow soil horizons, PROFILE produced higher weathering rates than the depletion method, particularly of K and Na in deeper soil horizons. The lower weathering rates of the depletion method were partly explained by natural and anthropogenic variability in Zr gradients. The base cation budget approach produced significantly higher weathering rates of BCs, 134.6 mmolc m−2 yr−1 at Asa and 73.2 mmolc m−2 yr−1 at Flakaliden, due to high rates estimated for the nutrient elements Ca, Mg and K, whereas weathering rates were lower and similar to those for the depletion method (6.6 and 2.2 mmolc m−2 yr−1 at Asa and Flakaliden). The large discrepancy in weathering rates for Ca, Mg and K between the base cation budget approach and the other methods suggests additional sources for tree uptake in the soil not captured by measurements.

The effects of space weathering on Apollo 17 mare soils: Petrographie and chemical characterization

2001 ◽  
Vol 36 (2) ◽  
pp. 285-299 ◽  
Author(s):  
Lawrence A. TAYLOR ◽  
Carlé PIETERS ◽  
Lindsay P. KELLER ◽  
Richard V. MORRIS ◽  
David S. McKAY ◽  
...  
Keyword(s):  
Chemical Characterization ◽  
Space Weathering

Iris (Manitobasat-1) – A Cubesat Mission To Study Space Weathering Of Planetary Surfaces: Payload Selection And Testing

2021 ◽  
Author(s):  
Stephanie A Connell ◽  
Nathalie Turenne ◽  
Ed Cloutis ◽  
Matt Driedger ◽  
Ali Barari ◽  
...  
Keyword(s):  
Space Weathering ◽  
Planetary Surfaces
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