Impact of a paleomagnetic field on sputtering loss of Martian atmospheric argon and neon

摘要: We examine the implications of including a paleomagnetic field on sputtering loss argon and neon from Martian atmosphere. In previous investigation [Hutchins Jakosky, 1996], we found that collisional exobase by oxygen pickup ions dramatically modified evolution atmospheric (removing greater than 85% outgassed 36Ar over time present allotment 20Ne in <100 Myr) could easily reproduce anomalous isotopic fractionation 36Ar/38Ar. However, existence an intrinsic magnetic limit deflecting solar wind around upper atmosphere, reducing number produced. Evaluation results lower rates if shut off between 2.5 3.6 Gyr. Nonetheless, extent requires input sources, addition to outgassing intrusive extrusive volcanism, capable providing 4–100 times more 40–1800 (than provided volcanic outgassing), dependent begins. The additional volatile source(s) must also preferentially outgas relative factor 10 26.