10:45 AM - 12:15 PM
[MIS21-P06] Transition of volcanic activity in Central Elysium Planitia, Mars suggested by topography of low shields
Keywords:Low shield, Mars, Lava flow morphology
Central Elysium Planitia (CEP) is a vast lava plain located in the southern part of Elysium Mons. Most of the surface in CEP is formed by lava erupted from Cerberus Fossae, but there are also areas formed by lava erupted from low shields (LSs). By discussing the lava effusion rate based on the morphology of lava erupted from the LS in addition to the lava flow from Cerberus Fossae, which has been discussed conventionally, we can clarify the spatiotemporal variation of the lava effusion rate and understand the volcanism history of CEP in detail. In this study, we aimed to discuss the volcanic activity history of the LSs in CEP by examining the LS’s topography and lava flow morphology.
In this study, we analyzed edifice topography and typed lava flow morphology for 17 LSs distributed in CEP. In particular, we focused on channel-fed flows (formed by high effusion rates compared to other types) and calculated the area of each edifice by polygon mapping using GIS tools.
The area of channel-fed flows tended to increase exponentially with increasing edifice diameter and edifice area. This suggests that the lava effusion rate was relatively high in LSs with large edifice diameters and edifice areas, and therefore channel-fed flows occupy larger areas on the edifice.
In LSs with circular craters, the area of channel-fed flows tends to decrease with the formation age. This suggests that the lava effusion rate may have gradually decreased after 71.73 Ma, in the case of LSs with circular craters.
Except for the two oldest LSs, the edifice area decreases with the formation age. The relationship between the formation age and specific height in the CEP LS shows that the specific height decreases with the formation age, although it is not a strong trend. This suggests that the amount of effused lava may have gradually decreased after 95 Ma.
In this presentation, we will present the details of our results and discussions and show the comparison with LSs in Tharsis region.
In this study, we analyzed edifice topography and typed lava flow morphology for 17 LSs distributed in CEP. In particular, we focused on channel-fed flows (formed by high effusion rates compared to other types) and calculated the area of each edifice by polygon mapping using GIS tools.
The area of channel-fed flows tended to increase exponentially with increasing edifice diameter and edifice area. This suggests that the lava effusion rate was relatively high in LSs with large edifice diameters and edifice areas, and therefore channel-fed flows occupy larger areas on the edifice.
In LSs with circular craters, the area of channel-fed flows tends to decrease with the formation age. This suggests that the lava effusion rate may have gradually decreased after 71.73 Ma, in the case of LSs with circular craters.
Except for the two oldest LSs, the edifice area decreases with the formation age. The relationship between the formation age and specific height in the CEP LS shows that the specific height decreases with the formation age, although it is not a strong trend. This suggests that the amount of effused lava may have gradually decreased after 95 Ma.
In this presentation, we will present the details of our results and discussions and show the comparison with LSs in Tharsis region.