Publications
118 results found
Cosgrove JW, Banham SG, Gupta S, et al., 2022, The Origin of the Fracture Networks in the Mudstones of Gale Crater Mars; Their Implications Regarding the State of Stress and Fluid Pressure During Their Formation and the Depth to Which They Were Buried, JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 127, ISSN: 2169-9097
Bell JF, Maki JN, Alwmark S, et al., 2022, Geological, multispectral, and meteorological imaging results from the Mars 2020 Perseverance rover in Jezero crater, SCIENCE ADVANCES, Vol: 8, ISSN: 2375-2548
Tice MM, Hurowitz JA, Allwood AC, et al., 2022, Alteration history of Séítah formation rocks inferred by PIXL x-ray fluorescence, x-ray diffraction, and multispectral imaging on Mars., Sci Adv, Vol: 8
Collocated crystal sizes and mineral identities are critical for interpreting textural relationships in rocks and testing geological hypotheses, but it has been previously impossible to unambiguously constrain these properties using in situ instruments on Mars rovers. Here, we demonstrate that diffracted and fluoresced x-rays detected by the PIXL instrument (an x-ray fluorescence microscope on the Perseverance rover) provide information about the presence or absence of coherent crystalline domains in various minerals. X-ray analysis and multispectral imaging of rocks from the Séítah formation on the floor of Jezero crater shows that they were emplaced as coarsely crystalline igneous phases. Olivine grains were then partially dissolved and filled by finely crystalline or amorphous secondary silicate, carbonate, sulfate, and chloride/oxychlorine minerals. These results support the hypothesis that Séítah formation rocks represent olivine cumulates altered by fluids far from chemical equilibrium at low water-rock ratios.
Farley KA, Stack KM, Shuster DL, et al., 2022, Aqueously altered igneous rocks sampled on the floor of Jezero crater, Mars, Science, Vol: 0
The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below the crater?s sedimentary delta, finding the floor consists of igneous rocks altered by water. The lowest exposed unit, informally named Séítah, is a coarsely crystalline olivine-rich rock, which accumulated at the base of a magma body. Fe-Mg carbonates along grain boundaries indicate reactions with CO2-rich water, under water-poor conditions. Overlying Séítah is a unit informally named Máaz, which we interpret as lava flows or the chemical complement to Séítah in a layered igneous body. Voids in these rocks contain sulfates and perchlorates, likely introduced by later near-surface brine evaporation. Core samples of these rocks were stored aboard Perseverance for potential return to Earth.
Liu Y, Tice MM, Schmidt ME, et al., 2022, An olivine cumulate outcrop on the floor of Jezero crater, Mars, SCIENCE, Vol: 377, Pages: 1513-+, ISSN: 0036-8075
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- Citations: 6
Caravaca G, Mangold N, Dehouck E, et al., 2022, From Lake to River: Documenting an Environmental Transition Across the Jura/Knockfarril Hill Members Boundary in the Glen Torridon Region of Gale Crater (Mars), JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 127, ISSN: 2169-9097
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- Citations: 11
Fedo CM, Bryk AB, Edgar LA, et al., 2022, Geology and Stratigraphic Correlation of the Murray and Carolyn Shoemaker Formations Across the Glen Torridon Region, Gale Crater, Mars, JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 127, ISSN: 2169-9097
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- Citations: 12
Banham SG, Gupta S, Rubin DM, et al., 2022, Evidence for Fluctuating Wind in Shaping an Ancient Martian Dune Field: The Stimson Formation at the Greenheugh Pediment, Gale Crater, JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 127, ISSN: 2169-9097
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- Citations: 9
Wiens RC, Udry A, Beyssac O, et al., 2022, Compositionally and density stratified igneous terrain in Jezero crater, Mars, SCIENCE ADVANCES, Vol: 8, ISSN: 2375-2548
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- Citations: 2
Gwizd S, Fedo C, Grotzinger J, et al., 2022, Sedimentological and Geochemical Perspectives on a Marginal Lake Environment Recorded in the Hartmann's Valley and Karasburg Members of the Murray Formation, Gale Crater, Mars, JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 127, ISSN: 2169-9097
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- Citations: 5
Watkins JA, Grotzinger JP, Stein NT, et al., 2022, Burial and Exhumation of Sedimentary Rocks Revealed by the Base Stimson Erosional Unconformity, Gale Crater, Mars, JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 127, ISSN: 2169-9097
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- Citations: 1
Rubin DM, Lapotre MAG, Stevens AW, et al., 2022, Ancient Winds, Waves, and Atmosphere in Gale Crater, Mars, Inferred From Sedimentary Structures and Wave Modeling, JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 127, ISSN: 2169-9097
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- Citations: 3
Mangold N, Gupta S, Gasnault O, et al., 2021, Perseverance rover reveals an ancient delta-lake system and flood deposits at Jezero crater, Mars, SCIENCE, Vol: 374, Pages: 711-717, ISSN: 0036-8075
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- Citations: 28
HolmAlwmark S, Kinch KM, Hansen MD, et al., 2021, Stratigraphic relationships in Jezero crater, Mars: constraints on the timing of fluvial‐lacustrine activity from orbital observations, Journal of Geophysical Research: Planets, Vol: 126, Pages: 1-31, ISSN: 2169-9097
On February 18, 2021 NASA's Perseverance rover landed in Jezero crater, located at the northwestern edge of the Isidis basin on Mars. The uppermost surface of the present-day crater floor is dominated by a distinct geologic assemblage previously referred to as the dark-toned floor. It consists of a smooth, dark-toned unit overlying and variably covering light-toned, roughly eroded deposits showing evidence of discrete layers. In this study, we investigated the stratigraphic relations between materials that comprise this assemblage, the main western delta deposit, as well as isolated mesas located east of the main delta body that potentially represent delta remnants. A more detailed classification and differentiation of crater floor units in Jezero and determination of their relative ages is vital for the understanding of the geologic evolution of the crater system, and determination of the potential timeline and environments of habitability. We have investigated unit contacts using topographic profiles and DEMs as well as the distribution of small craters and fractures on the youngest portions of the crater floor. Our results indicate that at least some of the deltaic deposition in Jezero postdates emplacement of the uppermost surface of the crater floor assemblage. The inferred age of the floor assemblage can therefore help to constrain the timing of the Jezero fluviolacustrine system, wherein at least some lake activity postdates the age of the uppermost crater floor. We present hypotheses that can be tested by Perseverance and can be used to advance our knowledge of the geologic evolution of the area.
Kumar Joshi S, Gupta S, Sinha R, et al., 2021, Strongly heterogeneous patterns of groundwater depletion in Northwestern India, Journal of Hydrology, Vol: 598, Pages: 1-17, ISSN: 0022-1694
Northwestern India has been identified as a significant hotspot of groundwater depletion, with major implications for groundwater sustainability caused by excessive abstraction. We know relatively little about the detailed spatial and temporal changes in groundwater storage in this region, nor do we understand the interplay of factors controlling these changes. Groundwater managers and policymakers in India require such information to monitor groundwater development and make strategic decisions for the sustainable management of groundwater. Here, we characterise high-resolution spatio-temporal variability in groundwater levels and storage change across northwestern India through analysis of in situ measurements of historical groundwater level data. We note a slow gain in groundwater storage of + 0.58 ± 0.35 km3 for the pre-monsoon and + 0.40 ± 0.35 km3 for the post-monsoon period between 1974 and 2001. However, from 2002 to 2010, groundwater storage was rapidly depleted by −32.30 ± 0.34 km3 in the pre-monsoon and −24.42 ± 0.34 km3 in the post-monsoon period. Importantly, we observe marked spatial heterogeneity in groundwater levels and storage change and distinct hotspots of groundwater depletion with lateral length scales of tens of kilometers. Spatial variability in groundwater abstraction partially explains the depletion pattern, but we also find that the sedimentological heterogeneity of the aquifer system correlates broadly with long-term patterns of groundwater-level change. This correlation, along with the spatial agreement between groundwater level change and water quality, provides a framework for anticipating future depletion patterns and guiding groundwater monitoring and domain-specific management strategies.
Davis JM, Grindrod PM, Banham SG, et al., 2021, A record of syn-tectonic sedimentation revealed by perched alluvial fan deposits in Valles Marineris, Mars, Geology, Vol: 49, Pages: 1250-1254, ISSN: 0091-7613
On Mars, basins formed by tectonic processes are rare and mostly have unconstrained subsidence histories. One method for understanding this record of subsidence is through associated alluvial fans, which are sourced from uplifted areas and accumulate in downthrown basins. The source, morphology, and superposition of fan deposits can be used to reconstruct fault kinematics, the relative timing of accommodation space formation, and, in turn, the influence tectonic processes had on Martian fan formation. Here we use high-resolution orbital data sets to characterize sediment fan deposits associated with syn-tectonic sedimentation in two regions of the Valles Marineris canyons: Coprates Chasma and Juventae Chasma. These deposits comprise sediment fans on the current canyon floor and low-gradient surfaces perched several kilometers above the canyon floor. We interpret the low-gradient surfaces as remnant sediment fan deposits, which originally formed at the former canyon floor and have since been offset due to normal faulting. The preservation of vertically offset generations of sediment fan deposits supports a progressive, basinward migration of fault activity into the original hanging wall or repeat activity along a fault zone. Each episode of faulting was followed by a basinward shift in drainages, which led to fault-scarp degradation and formation of a new generation of fans. Multiple episodes of syn-tectonic sedimentation occurred during the evolution of the basins, with fluvial activity sporadically active. Our results demonstrate, for the first time on Mars, that depositional cyclicity was linked to tectonic deformation, possibly representative of regional processes throughout Valles Marineris.
Arosio R, Collier JS, Hawes J, et al., 2021, New perspectives on the English Channel megaflood hypothesis: High-resolution multibeam and seabed camera imaging of submarine landforms in the Northern Palaeovalley, Geomorphology, Vol: 382, Pages: 1-15, ISSN: 0169-555X
A network of large, bedrock-incised valleys is preserved on the seabed of the English Channel. Based on analysis of a 30 × 30 m bathymetric grid, the morphology of the valleys was interpreted to be a consequence of erosion by catastrophic flood processes from overspill of a large proglacial lake in the Southern North Sea. The significance of the “megaflood features” has since been recognized by the UK Government with the designation of their protected status in one of three Marine Protected Areas (MPAs) within the palaeovalley in the central English Channel. Here, we analyse recent multibeam bathymetry data (2 × 2 m DEM) from these MPAs, together with backscatter and high-definition seabed camera imagery. The new data allow us to ground truth and refine the earlier interpretation and recognize previously undiscovered finer features. Streamlined valley margins, streamlined islands and metres-deep scours eroded into the valley floor are described at higher detail, while new subtle features on the valley floor such as kilometre-long, sub-parallel inner channels and streamlined bedrock ridges are identified for the first time. These features are consistent with a high energy erosion origin. We also identify isolated large boulders (>1 m length) on flat seabed on the flanks of the palaeovalley, which are consistent with deposition from megaflood processes, although wave action during transgression/regression cannot be ruled out. Our new results enable more robust morphological evidence to support the influence of catastrophic flooding on bedrock valley incision in the English Channel.
Banham SG, Gupta S, Rubin DM, et al., 2021, A Rock Record of Complex Aeolian Bedforms in a Hesperian Desert Landscape: The Stimson Formation as Exposed in the Murray Buttes, Gale Crater, Mars, JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 126, ISSN: 2169-9097
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- Citations: 26
Fraeman AA, Edgar LA, Rampe EB, et al., 2020, Evidence for a diagenetic origin of vera rubin ridge, gale crater, Mars: summary and synthesis of curiosity's exploration campaign, Journal of Geophysical Research: Planets, Vol: 125, Pages: 1-34, ISSN: 2169-9097
This paper provides an overview of the Curiosity rover's exploration at Vera Rubin ridge (VRR) and summarizes the science results. VRR is a distinct geomorphic feature on lower Aeolis Mons (informally known as Mount Sharp) that was identified in orbital data based on its distinct texture, topographic expression, and association with a hematite spectral signature. Curiosity conducted extensive remote sensing observations, acquired data on dozens of contact science targets, and drilled three outcrop samples from the ridge, as well as one outcrop sample immediately below the ridge. Our observations indicate that strata composing VRR were deposited in a predominantly lacustrine setting and are part of the Murray formation. The rocks within the ridge are chemically in family with underlying Murray formation strata. Red hematite is dispersed throughout much of the VRR bedrock, and this is the source of the orbital spectral detection. Gray hematite is also present in isolated, gray-colored patches concentrated toward the upper elevations of VRR, and these gray patches also contain small, dark Fe-rich nodules. We propose that VRR formed when diagenetic event(s) preferentially hardened rocks, which were subsequently eroded into a ridge by wind. Diagenesis also led to enhanced crystallization and/or cementation that deepened the ferric-related spectral absorptions on the ridge, which helped make them readily distinguishable from orbit. Results add to existing evidence of protracted aqueous environments at Gale crater and give new insight into how diagenesis shaped Mars' rock record.
Stack KM, Williams NR, Calef F, et al., 2020, Photogeologic Map of the Perseverance Rover Field Site in Jezero Crater Constructed by the Mars 2020 Science Team, SPACE SCIENCE REVIEWS, Vol: 216, ISSN: 0038-6308
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- Citations: 32
Edgett KS, Banham SG, Bennett KA, et al., 2020, Extraformational sediment recycling on Mars, Geosphere, Vol: 16, ISSN: 1553-040X
Extraformational sediment recycling (old sedimentary rock to new sedimentary rock) is a fundamental aspect of Earth’s geological record; tectonism exposes sedimentary rock, whereupon it is weathered and eroded to form new sediment that later becomes lithified. On Mars, tectonism has been minor, but two decades of orbiter instrument–based studies show that some sedimentary rocks previously buried to depths of kilometers have been exposed, by erosion, at the surface. Four locations in Gale crater, explored using the National Aeronautics and Space Administration’s Curiosity rover, exhibit sedimentary lithoclasts in sedimentary rock: At Marias Pass, they are mudstone fragments in sandstone derived from strata below an erosional unconformity; at Bimbe, they are pebble-sized sandstone and, possibly, laminated, intraclast-bearing, chemical (calcium sulfate) sediment fragments in conglomerates; at Cooperstown, they are pebble-sized fragments of sandstone within coarse sandstone; at Dingo Gap, they are cobble-sized, stratified sandstone fragments in conglomerate derived from an immediately underlying sandstone. Mars orbiter images show lithified sediment fans at the termini of canyons that incise sedimentary rock in Gale crater; these, too, consist of recycled, extraformational sediment. The recycled sediments in Gale crater are compositionally immature, indicating the dominance of physical weathering processes during the second known cycle. The observations at Marias Pass indicate that sediment eroded and removed from craters such as Gale crater during the Martian Hesperian Period could have been recycled to form new rock elsewhere. Our results permit prediction that lithified deltaic sediments at the Perseverance (landing in 2021) and Rosalind Franklin (landing in 2023) rover field sites could contain extraformational recycled sediment.
Sembhi H, Wooster M, Zhang T, et al., 2020, Post-monsoon air quality degradation across Northern India: assessing the impact of policy-related shifts in timing and amount of crop residue burnt, Environmental Research Letters, Vol: 15, Pages: 1-13, ISSN: 1748-9326
The past decade has seen episodes of increasingly severe air pollution across much of the highly populated Indo-Gangetic Plain (IGP), particularly during the post-monsoon season when crop residue burning (CRB) is most prevalent. Recent studies have suggested that a major, possibly dominant contributor to this air quality decline is that northwest (NW) Indian rice residue burning has shifted later into the post-monsoon season, as an unintended consequence of a 2009 groundwater preservation policy that delayed the sowing of irrigated rice paddy. Here we combine air quality modelling of fine particulate matter (PM2.5) over IGP cities, with meteorology, fire and smoke emissions data to directly test this hypothesis. Our analysis of satellite-derived agricultural fires shows that an approximate 10 d shift in the timing of NW India post-monsoon residue burning occurred since the introduction of the 2009 groundwater preservation policy. For the air quality crisis of 2016, we found that NW Indian CRB timing shifts made a small contribution to worsening air quality (3% over Delhi) during the post-monsoon season. However, if the same agricultural fires were further delayed, air quality in the CRB source region (i.e. Ludhiana) and for Delhi could have deteriorated by 30% and 4.4%, respectively. Simulations for other years highlight strong inter-annual variabilities in the impact of these timing shifts, with the magnitude and even direction of PM2.5 concentration changes strongly dependent on specific meteorological conditions. Overall we find post-monsoon IGP air quality to be far more sensitive to meteorology and the amount of residue burned in the fields of NW India than to the timing shifts in residue burning. Our study calls for immediate actions to provide farmers affordable and sustainable alternatives to residue burning to hasten its effective prohibition, which is paramount to reducing the intensity of post-monsoon IGP air pollution episodes.
Balme MR, Gupta S, Davis JM, et al., 2020, Aram Dorsum: An Extensive Mid-Noachian Age Fluvial Depositional System in Arabia Terra, Mars, JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 125, ISSN: 2169-9097
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- Citations: 15
Edgar LA, Fedo CM, Gupta S, et al., 2020, A Lacustrine Paleoenvironment Recorded at Vera Rubin Ridge, Gale Crater: Overview of the Sedimentology and Stratigraphy Observed by the Mars Science Laboratory Curiosity Rover, JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 125, ISSN: 2169-9097
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- Citations: 64
Rivera-Hernandez F, Sumner DY, Mangold N, et al., 2020, Grain Size Variations in the Murray Formation: Stratigraphic Evidence for Changing Depositional Environments in Gale Crater, Mars, JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 125, ISSN: 2169-9097
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- Citations: 26
Stack KM, Grotzinger JP, Lamb MP, et al., 2019, Evidence for plunging river plume deposits in the Pahrump Hills member of the Murray formation, Gale crater, Mars, Sedimentology, Vol: 65, Pages: 1768-1802, ISSN: 0037-0746
Recent robotic missions to Mars have offered new insights into the extent, diversity and habitability of the Martian sedimentary rock record. Since the Curiosity rover landed in Gale crater in August 2012, the Mars Science Laboratory Science Team has explored the origins and habitability of ancient fluvial, deltaic, lacustrine and aeolian deposits preserved within the crater. This study describes the sedimentology of a ca 13 m thick succession named the Pahrump Hills member of the Murray formation, the first thick fine‐grained deposit discovered in situ on Mars. This work evaluates the depositional processes responsible for its formation and reconstructs its palaeoenvironmental setting. The Pahrump Hills succession can be sub‐divided into four distinct sedimentary facies: (i) thinly laminated mudstone; (ii) low‐angle cross‐stratified mudstone; (iii) cross‐stratified sandstone; and (iv) thickly laminated mudstone–sandstone. The very fine grain size of the mudstone facies and abundant millimetre‐scale and sub‐millimetre‐scale laminations exhibiting quasi‐uniform thickness throughout the Pahrump Hills succession are most consistent with lacustrine deposition. Low‐angle geometric discordances in the mudstone facies are interpreted as ‘scour and drape’ structures and suggest the action of currents, such as those associated with hyperpycnal river‐generated plumes plunging into a lake. Observation of an overall upward coarsening in grain size and thickening of laminae throughout the Pahrump Hills succession is consistent with deposition from basinward progradation of a fluvial‐deltaic system derived from the northern crater rim into the Gale crater lake. Palaeohydraulic modelling constrains the salinity of the ancient lake in Gale crater: assuming river sediment concentrations typical of floods on Earth, plunging river plumes and sedimentary structures like those observed at Pahrump Hills would have required lake densities near freshwater to form. The dep
Davis JM, Gupta S, Balme M, et al., 2019, A diverse array of fluvial depositional systems in arabia terra: Evidence for mid‐noachian to early hesperian rivers on Mars, Journal of Geophysical Research: Planets, Vol: 124, Pages: 1913-1934, ISSN: 2169-9097
Branching to sinuous ridges systems, 100s of kilometers in length and comprising layered strata, are present across much of Arabia Terra, Mars. These ridges are interpreted as depositional fluvial channels, now preserved as inverted topography. Here we use high resolution image and topographic datasets to investigate the morphology of these depositional systems and show key examples of their relationships to associated fluvial landforms. The inverted channel systems likely comprise indurated conglomerate, sandstone, and mudstone bodies, which form a multi‐storey channel stratigraphy. The channel systems intersect local basins and indurated sedimentary mounds, that we interpret as paleolake deposits. Some inverted channels are located within erosional valley networks, which have regional and local catchments. Inverted channels are typically found in downslope sections of valley networks, sometimes at the margins of basins, and numerous different transition morphologies are observed. These relationships indicate a complex history of erosion and deposition, possibly controlled by changes in water or sediment flux, or base level variation. Other inverted channel systems have no clear preserved catchment; likely lost due to regional resurfacing of upland areas. Sediment may have been transported through Arabia Terra towards the dichotomy and stored in local and regional‐scale basins. Regional stratigraphic relations suggest these systems were active between the mid‐Noachian and early Hesperian. The morphology of these systems is supportive of an early Mars climate which was characterized by prolonged precipitation and runoff.
Durcan JA, Thomas DSG, Gupta S, et al., 2019, Holocene landscape dynamics in the Ghaggar-Hakra palaeochannel region at the northern edge of the Thar Desert, northwest India, Quaternary International, Vol: 501, Pages: 317-327, ISSN: 1040-6182
Precession-forced change in insolation has driven de-intensification of the Asian Monsoon systems during the Holocene. Set against this backdrop of a weakening monsoon, Indus Civilisation populations occupied a number of urban settlements on the Ghaggar-Hakra plains during the mid-Holocene from 4.5 ka until they were abandoned by around 3.9 ka. Regional climatic variability has long been cited as a potential factor in the transformation of Indus society, however there remain substantial gaps in the chronological framework for regional climatic and environmental change at the northern margin of the Thar Desert. This makes establishing a link between climate, environment and society challenging. This paper presents 24 optically stimulated luminescence ages from a mixture of 11 fluvial and aeolian sedimentological sites on the Ghaggar-Hakra floodplain/interfluve, an area which was apparently densely populated during the Indus urban phase and subsequently. These ages identify fluvial deposition which mostly pre-dates 5 ka, although fluvial deposits are detected in the Ghaggar palaeochannel at 3.8 ka and 3.0 ka, post-dating the decline of urbanism. Aeolian accumulation phases occur around 9 ka, 6.5 ka, 2.8 ka and 1.7 ka. There is no clear link to a 4.2 ka abrupt climate event, nor is there a simple switch between dominant fluvial deposition and aeolian accumulation, and instead the OSL ages reported present a view of a highly dynamic geomorphic system during the Holocene. The decline of Indus urbanism was not spatially or temporally instantaneous, and this paper suggests that the same can be said for the geomorphic response of the northern Thar to regional climate change.
García-Moreno D, Gupta S, Collier JS, et al., 2019, Middle–Late Pleistocene landscape evolution of the Dover Strait inferred from buried and submerged erosional landforms, Quaternary Science Reviews, Vol: 203, Pages: 209-232, ISSN: 0277-3791
Prominent landforms, either buried or preserved at the seafloor, provide important constraints on the processes that led to the opening and present-day configuration of the Dover Strait. Here, we extend previous investigations on two distinct landform features, the Fosse Dangeard and Lobourg Channel, to better understand the poly-phase history of their formation and inferences for the opening and Pleistocene evolution of the Dover Strait. The Fosse Dangeard consist of several interconnected palaeo-depressions. Their morphology and spatial distribution are interpreted to be the result of plunge-pool erosion generated at the base of north-eastward retreating waterfalls. Their infills comprise internal erosional surfaces that provide evidence for the occurrence of several erosional episodes following their initial incision. The Lobourg Channel comprises various sets of erosional features, attesting to the occurrence of several phases of intense fluvial and/or flood erosion. The last one of these carved a prominent inner channel, which truncates the uppermost infill of the Fosse Dangeard. The morphology of the Lobourg inner channel and the erosional features associated with its incision strongly resemble landforms found in megaflood-eroded terrains, indicating that this valley was likely eroded by one or several megafloods. Our study therefore corroborates the existence of waterfalls in the Dover Strait at least once during the Pleistocene Epoch. It also provides evidence of the occurrence of multiple episodes of fluvial and flood erosion, including megafloods. Finally, this study allows us to establish a relative chronology of the erosional/depositional episodes that resulted in the present-day morphology of this region.
Balme MR, Curtis-Rouse MC, Banham S, et al., 2019, The 2016 UK Space Agency Mars Utah Rover Field Investigation (MURFI), PLANETARY AND SPACE SCIENCE, Vol: 165, Pages: 31-56, ISSN: 0032-0633
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- Citations: 4
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