相关论文: The Timing of Alluvial Fan Formation on Mars

Large alluvial fan deposits on Mars record relatively recent habitable surface conditions ($\lesssim$3.5 Ga, Late Hesperian - Amazonian). We find net sedimentation rate <(4-8) {\mu}m/yr in the alluvial-fan deposits, using the frequency of…

Early Mars climate research has well-defined goals (Mars Exploration Program Analysis Group 2018). Achieving these goals requires geologists and climate modelers to coordinate. Coordination is easier if results are expressed in terms of…

The climate of early Mars remains a topic of intense debate. Ancient terrains preserve landscapes consistent with stream channels, lake basins, and possibly even oceans, and thus the presence of liquid water flowing on the Martian surface 4…

The debate over the early Martian climate is among the most intriguing in planetary science. Although the geologic evidence generally supports a warmer and wetter climate, climate models have had difficulty simulating such a scenario,…

Evidence for fluvial features and standing liquid water indicate that Mars was a warmer and wetter place in its past; however, climate models have historically been unable to produce conditions to yield a warm early Mars under the faint…

The nature of the early Martian climate is one of the major unanswered questions of planetary science. Key challenges remain, but a new wave of orbital and in situ observations and improvements in climate modeling have led to significant…

Mars' transition from an early "warm and wet" to the "cold and dry" environment left fingerprints on the geological record of fluvial activity on Mars. The morphological and mineralogical observations of aqueous activity provided varying…

Unraveling the stratigraphic record is the key to understanding ancient climate and past climate changes on Mars. River deposits when placed in stratigraphic order could constrain the number, magnitudes, and durations of the wettest…

Early Mars had rivers, but the cause of Mars' wet-to-dry transition remains unknown. Past climate on Mars can be probed using the spatial distribution of climate-sensitive landforms. We analyzed global databases of water-worked landforms…

Mars' surface bears the imprint of valley networks formed billions of years ago and their relicts can still be observed today. However, whether these networks were formed by groundwater sapping, ice melt, or fluvial runoff has been…

For decades, scientists have tried to explain the evidence for fluvial activity on early Mars, but a consensus has yet to emerge regarding the mechanism for producing it. One hypothesis suggests early Mars was warmed by a thick greenhouse…

Mars' wet-to-dry transition is a major environmental catastrophe, yet the spatial pattern, tempo, and cause of drying are poorly constrained. We built a globally-distributed database of constraints on Mars late-stage paleolake size relative…

Mars is the only planet, other than Earth, for which there are several evidences that liquid water was abundant at the surface. Among them, one of the best evidence is that the ancient terrains of Mars are covered with fluvial and…

Reconciling the geology of Mars with models of atmospheric evolution remains a major challenge. Martian geology is characterized by past evidence for episodic surface liquid water, and geochemistry indicating a slow and intermittent…

We compare estimates of atmospheric precipitation during the Martian Noachian-Hesperian boundary 3.8 Gyr ago as calculated in a radiative-convective column model of the atmosphere with runoff values estimated from a geomorphological…

The Martian obliquity cycle is predominately influenced by Solar and Jovian tidal forces. The present-day axial tilt of Mars (25 degrees) is predicted to cycle between 0 degrees and 60 degrees (Mischna & Richardson 2005) with excursions up…

The decay of the martian atmosphere - which is dominated by carbon dioxide - is a component of the long-term environmental change on Mars from a climate that once allowed rivers to flow to the cold and dry conditions of today. The minimum…

The climate on early Mars is one of the major unsolved problems. It is unclear whether early Mars was warm and wet or cold and icy. Morphological features on Mars such as sinuous ridges could provide critical constraints to address this…

River deposits are one of the main lines of evidence that tell us that Mars once had a climate different from today, and so changes in river deposits with time tell us something about how Mars climate changed with time. In this study, we…

Post-Noachian Martian paleochannels indicate the existence of liquid water on the surface of Mars after about 3.5 Gya (Irwin et al., 2015; Palucis et al., 2016). In order to explore the effects of variations in CO$_{2}$ partial pressure and…