Stack Kathryn M, Dietrich William E, Lamb Michael P, Sullivan Robert J, Christian John R, Newman Claire E, O'Connell-Cooper Catherine D, Sneed Jonathan W, Day Mackenzie, Baker Mariah, Arvidson Raymond E, Fedo Christopher M, Khan Sabrina, Williams Rebecca M E, Bennett Kristen A, Bryk Alexander B, Cofield Shannon, Edgar Lauren A, Fox Valerie K, Fraeman Abigail A, House Christopher H, Rubin David M, Sun Vivian Z, Van Beek Jason K
Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA.
Department of Earth and Planetary Science University of California, Berkeley Berkeley CA USA.
J Geophys Res Planets. 2022 Jun;127(6):e2021JE007096. doi: 10.1029/2021JE007096. Epub 2022 May 26.
Gale crater, the field site for NASA's Mars Science Laboratory Curiosity rover, contains a diverse and extensive record of aeolian deposition and erosion. This study focuses on a series of regularly spaced, curvilinear, and sometimes branching bedrock ridges that occur within the Glen Torridon region on the lower northwest flank of Aeolis Mons, the central mound within Gale crater. During Curiosity's exploration of Glen Torridon between sols ∼2300-3080, the rover drove through this field of ridges, providing the opportunity for in situ observation of these features. This study uses orbiter and rover data to characterize ridge morphology, spatial distribution, compositional and material properties, and association with other aeolian features in the area. Based on these observations, we find that the Glen Torridon ridges are consistent with an origin as wind-eroded bedrock ridges, carved during the exhumation of Mount Sharp. Erosional features like the Glen Torridon ridges observed elsewhere on Mars, termed periodic bedrock ridges (PBRs), have been interpreted to form transverse to the dominant wind direction. The size and morphology of the Glen Torridon PBRs are consistent with transverse formative winds, but the orientation of nearby aeolian bedforms and bedrock erosional features raise the possibility of PBR formation by a net northeasterly wind regime. Although several formation models for the Glen Torridon PBRs are still under consideration, and questions persist about the nature of PBR-forming paleowinds, the presence of PBRs at this site provides important constraints on the depositional and erosional history of Gale crater.
盖尔陨石坑是美国国家航空航天局“好奇号”火星科学实验室探测器的实地探测地点，保存着丰富多样的风成沉积与侵蚀记录。本研究聚焦于一系列规则分布、呈曲线状且有时分支的基岩脊，它们位于盖尔陨石坑中央山丘埃奥利斯山（Aeolis Mons）西北侧下部的格伦托里登（Glen Torridon）地区。在“好奇号”于第2300个火星日至3080个火星日期间对格伦托里登地区进行探测时，探测器驶过这片基岩脊区域，为实地观测这些地貌特征提供了契机。本研究利用轨道器和探测器数据，对基岩脊的形态、空间分布、成分和物质属性以及与该地区其他风成地貌的关联进行了表征。基于这些观测结果，我们发现格伦托里登基岩脊与夏普山（Mount Sharp）隆升过程中风蚀基岩脊的成因相符。在火星其他地方观测到的类似格伦托里登基岩脊的侵蚀地貌，被称为周期性基岩脊（PBRs），被解释为与主导风向垂直形成。格伦托里登周期性基岩脊的大小和形态与横向形成风一致，但附近风成床形和基岩侵蚀地貌的方向增加了由东北向净风况形成周期性基岩脊的可能性。尽管格伦托里登周期性基岩脊的几种形成模型仍在探讨之中，关于形成周期性基岩脊的古风向的性质也仍存在疑问，但该地点周期性基岩脊的存在为盖尔陨石坑的沉积和侵蚀历史提供了重要限制。
