Formation process of polygons in central Dronning Maud Land, East Antarctica: Development for elucidation of Martian surface environment

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K12971
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Geography
• Research Institution: Oita University
• Principal Investigator: KOYAMA Takushi 大分大学, 教育学部, 准教授 (30553581)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 南極 / ポリゴン / UAV-SｆM測量 / 火星 / 地表環境 / 周氷河地形 / リモートセンシング / 尾根谷度

Outline of Final Research Achievements

To address these problems, we developed an UAV-SfM survey at Vassdalen in central Dronning Maud Land, East Antarctica and produced a decimeter-scale high-resolution DEM over an area of ~1.5 km by ~3 km area that contained moraine surfaces with various abandonment ages and differing polygon development. At some key polygons on key surfaces, we produced even higher-resolution DEMs using photographs taken from a high-view camera attached to a 3.5-m high pole using SfM analysis. Additionally, we conducted pit excavations across marginal troughs in these key polygons to examine the subsurface wedge structures. We present the results of these investigations including our effort to evaluate the size distribution of the polygons using a “ridgeness” parameter I calculated from the DEMs as well as pit exposure logs and discuss the temporal changes in the polygon sizes and the relation between the subsurface wedge structures and three-dimensional form of the surfaces of the polygons.

Free Research Field

自然地理学

Academic Significance and Societal Importance of the Research Achievements

近年，地球上で最も火星に近い環境下（極低温乾燥環境下）にある南極の微地形は，火星の表層環境のアナログとして注目されている。ポリゴンに代表される南極の微地形の形態・規模，地下構造，およびプロセス調査に基づき火星の地表環境や浅部地下構造が類推されてきた。本研究によって，地球側（南極）の地形データが高精度化されたことで，火星の一部地域の地表環境を推定することができた。この成果は，2030年代実施予定の火星テラフォーミングの研究への貢献や火星探査機の開発などにも十分寄与できると考えている。