An unnamed valley in Memnonia Fossae region, Mars: Evidence for Hydrological Activities

Abstract

Understanding Martian valley networks is crucial for deciphering the planet's paleoclimate and exploring the possibility that past or present subsurface water reservoirs, could harbor microbial life. In this context, the present study focuses on an unnamed valley system in the Memnonia quadrangle region of Mars, comprising two distinct valleys: Valley 1 and Valley 2. The goal of this study is to conduct a comprehensive analysis of these valleys to unravel their formation processes and hydrological dynamics, contributing to a deeper understanding of Mars's hydrological history. To achieve this, orbital remote sensing data are utilized to examine the topography and geomorphology of the whole of the unnamed valley system. Image data from cameras onboard Mars Reconnaissance Orbiter (MRO) are utilized to analyze the geomorphology of the region. Additionally, the Mars Global Surveyor’s (MGS) topographic data is used. Observations and results reveal the complex geological setting of the unnamed valley system within the Memnonia quadrangle, which is characterized by diverse terrain features and evidence of past fluvial and volcanic activity. Valley 1 and Valley 2 exhibit distinct morphological characteristics, with Valley 1 showing signs of erosion and sedimentary infilling, whereas Valley 2 displays a flat floor with no discernible morphological features. Key craters in the vicinity provide valuable insights into the timing of fluvial activities within the valley system. Chronological analyses based on CSFD curves suggest that Valley 1 was active between approximately 3.9 billion years ago and 3.5 billion years ago, and likewise Valley 2 was likely active during the same period. Volcanic activity around the early Hesperian epoch marked the cessation of fluvial processes in the region. In conclusion, this study sheds light on the paleo-hydrological dynamics of Mars through a detailed examination of the unnamed valley system in the Memnonia quadrangle.