Several irregularly shaped craters located within Arabia Terra, Mars, represent a new type of highland volcanic construct and together constitute a previously unrecognized Martian igneous province. ...Similar to terrestrial supervolcanoes, these low-relief paterae possess a range of geomorphic features related to structural collapse, effusive volcanism and explosive eruptions. Extruded lavas contributed to the formation of enigmatic highland ridged plains in Arabia Terra. Outgassed sulphur and erupted fine-grained pyroclastics from these calderas probably fed the formation of altered, layered sedimentary rocks and fretted terrain found throughout the equatorial region. The discovery of a new type of volcanic construct in the Arabia volcanic province fundamentally changes the picture of ancient volcanism and climate evolution on Mars. Other eroded topographic basins in the ancient Martian highlands that have been dismissed as degraded impact craters should be reconsidered as possible volcanic constructs formed in an early phase of widespread, disseminated magmatism on Mars.
Magmatism and volcanism have evolved the Martian lithosphere, surface, and climate throughout the history of Mars. Constraining the rates of magma generation and timing of volcanism on the surface ...clarifies the ways in which magma and volcanic activity have shaped these Martian systems. The ages of lava flows on other planets are often estimated using impact crater counts, assuming that the number and size-distribution of impact craters per unit area reflect the time the lava flow has been on the surface and exposed to potential impacts. Here we show that impact crater age model uncertainty is reduced by adding stratigraphic information observed at locations where neighboring lavas abut each other, and demonstrate the significance of this reduction in age uncertainty for understanding the history of a volcanic field comprising 29 vents in the 110-km-diameter caldera of Arsia Mons, Mars. Each vent within this caldera produced lava flows several to tens of kilometers in length; these vents are likely among the youngest on Mars, since no impact craters in their lava flows are larger than 1 km in diameter. First, we modeled the age of each vent with impact crater counts performed on their corresponding lava flows and found very large age uncertainties for the ages of individual vents, often spanning the estimated age for the entire volcanic field. The age model derived from impact crater counts alone is broad and unimodal, with estimated peak activity in the field around 130 Ma. Next we applied our volcano event age model (VEAM), which uses a directed graph of stratigraphic relationships and random sampling of the impact crater age determinations to create alternative age models. Monte Carlo simulation was used to create 10,000 possible vent age sets. The recurrence rate of volcanism is calculated for each possible age set, and these rates are combined to calculate the median recurrence rate of all simulations. Applying this approach to the 29 volcanic vents, volcanism likely began around 200–300 Ma then first peaked around 150 Ma, with an average production rate of 0.4 vents per Myr. The recurrence rate estimated including stratigraphic data is distinctly bimodal, with a second, lower peak in activity around 100 Ma. Volcanism then waned until the final vents were produced 10–90 Ma. Based on this model, volume flux is also bimodal, reached a peak rate of 1–8 km3 Myr−1 by 150 Ma and remained above half this rate until about 90 Ma, after which the volume flux diminished greatly. The onset of effusive volcanism from 200–150 Ma might be due to a transition of volcanic style away from explosive volcanism that emplaced tephra on the western flank of Arsia Mons, while the waning of volcanism after the 150 Ma peak might represent a larger-scale diminishing of volcanic activity at Arsia Mons related to the emplacement of flank apron lavas.
•A statistical model combines two data sources to constrain volcanic recurrence rate.•The most recent activity at Arsia Mons peaked at 150 Ma and ceased by 10–90 Ma.•The average vent production rate at its peak was 0.4 volcanic vents per Myr.•At the peak of activity, magma flux at the surface was 1–8 cu. km per Myr
Volcanic flood basalt eruptions have been linked to or are contemporaneous with major climate
disruptions, ocean anoxic events, and mass extinctions throughout at least the last 400M years of
Earth’s ...history. Previous studies and recent history have shown that volcanically-driven climate
cooling can occur through reflection of sunlight by H2SO4 aerosols, while longer-term climate
warming can occur via CO2 emissions. We use the Goddard Earth Observing System Chemistry-
Climate Model to simulate a four-year duration volcanic SO2 emission of the scale of the Wapshilla
Ridge member of the Columbia River Basalt eruption. Brief cooling from H2SO4 aerosols is
outweighed by dynamically and radiatively driven warming of the climate through a three orders
of magnitude increase in stratospheric H2O vapor.
The morphology and topography of volcanic landforms provide critical information to the investigation of their tectonic setting and the physical characteristics (e.g., rheology) of their eruption ...products. Their investigation is also an important prerequisite for studies of comparative planetology, (e.g., the comparison between surface features of the Earth and other planetary bodies). Numerous small and low shield volcanoes on Mars and associated vents and lava flows have previously been compared to terrestrial plains-style volcanism, which is defined as being an intermediate style between flood basalts and the Hawai'ian shields. This study investigates the topography and morphology of Martian landforms associated with plains volcanism using MOLA, MOC, THEMIS, HRSC, and HiRISE data. Low shields and other landforms of plains volcanism on Mars display similarities with terrestrial basaltic volcanic fields, and we do not observe any features that do not have morphologic analogues on Earth. The most typical landforms of Martian plains-style volcanism are low shields, defined as volcanic shields with diameters of typically less than 50 km, heights of a few hundred meters only, and extremely shallow flank slopes of less than 0.5°. Other surface features related to plains-style volcanism on Mars are craters, fissure vents, cinder and spatter cones, lava flows (that are commonly associated with lava channels and tubes), lava inflation features, and volcanic rift zones. Our results reconfirm the Viking Orbiter-based conclusion that plains volcanism in the eastern Snake River Plains is perhaps the best terrestrial morphological analogue for these Martian surface features. Icelandic shields, distinct structures in Hawai'i, and other basaltic landforms also show similarities to Martian plains volcanism. Sinuous rilles, previously not described in association with plains volcanism on Mars, are interpreted as evidence for high eruption rates. The extremely shallow flank slopes of the low shields suggest the eruption of shield-building lavas with low viscosity, which might be the result of high eruption temperatures, high effusion rates, a low Si- and a high Mg-content along with a possible high Fe-content, or a combination of these factors. The spatial distribution of low shield clusters in Tharsis does not show any obvious association with large-scale tectonic features. Plains volcanism might represent a relatively recent type of volcanism on Mars, which is not related to mantle plumes but to a zone of partial melting in an anomalously warm mantle underneath a thickened crust (Schumacher and Breuer, Geophys. Res. Lett. 34, L14202, doi: 10.1029/2007GL030083, 2007).
Inflation of narrow tube-fed basaltic lava flows (tens of meters across), such as those confined by topography, can be focused predominantly along the roof of a lava tube. This can lead to the ...development of an unusually long tumulus, its shape matching the sinuosity of the underlying lava tube. Such a situation occurred during Kīlauea Volcano's (Hawai'i, USA) ongoing East Rift Zone eruption on a lava tube active from July through November 2010. Short-lived breakouts from the tube buried the flanks of the sinuous, ridge-like tumulus, while the tumulus crest, its surface composed of lava formed very early in the flow's emplacement history, remained poised above the surrounding younger flows. At least several of these breakouts resulted in irrecoverable uplift of the tube roof. Confined sections of the prehistoric Carrizozo and McCartys flows (New Mexico, USA) display similar sinuous, ridge-like features with comparable surface age relationships. We contend that these distinct features formed in a fashion equivalent to that of the sinuous tumulus that formed at Kīlauea in 2010. Moreover, these sinuous tumuli may be analogs for some sinuous ridges evident in orbital images of the Tharsis volcanic province on Mars. The short-lived breakouts from the sinuous tumulus at Kīlauea were caused by surges in discharge through the lava tube, in response to cycles of deflation and inflation (DI events) at Kīlauea's summit. The correlation between DI events and subsequent breakouts aided in lava flow forecasting. Breakouts from the sinuous tumulus advanced repeatedly toward the sparsely populated Kalapana Gardens subdivision, destroying two homes and threatening others. Hazard assessments, including flow occurrence and advance forecasts, were relayed regularly to the Hawai'i County Civil Defense to aid their lava flow hazard mitigation efforts while this lava tube was active.
•We describe the development of a sinuous tumulus over an active lava tube.•Deflation–inflation cycles at Kīlauea's summit led to short-lived tube breakouts.•Forecasts of tube breakouts aided in hazard assessments.•The sinuous tumulus may be an analog for features in New Mexico, USA, and on Mars.
X-ray fluorescence (XRF) spectroscopy is a well-established and commonly used technique in obtaining diagnostic compositional data on geological samples. Recently, developments in X-ray tube and ...detector technologies have resulted in miniaturized, field-portable instruments that enable new applications both in and out of standard laboratory settings. These applications, however, have not been extensively applied to geologic field campaigns. This study investigates the feasibility of using developing handheld XRF (hXRF) technology to enhance terrestrial field geology, with potential applications in planetary surface exploration missions. We demonstrate that the hXRF is quite stable, providing reliable and accurate data continuously over a several year period. Additionally, sample preparation is proved to have a marked effect on the strategy for collecting and assimilating hXRF data. While the hXRF is capable of obtaining data that are comparable to laboratory XRF analysis for several geologically-important elements (such as Si, Ca, Ti, and K), the instrument is unable to detect other elements (such as Mg and Na) reliably. While this limits the use of the hXRF, especially when compared to laboratory XRF techniques, the hXRF is still capable of providing the field user with significantly improved contextual awareness of a field site, and more work is needed to fully evaluate the potential of this instrument in more complex geologic environments.
•We evaluate strengths, weaknesses, and best practices for using handheld XRF.•The handheld XRF (hXRF) is a valuable tool for terrestrial field geology.•The hXRF provides data for some elements that is comparable to laboratory XRF instruments.•When using the hXRF, sample preparation affects data analysis and interpretation.
The volcanic history of Syria Planum, Mars Richardson, Jacob A.; Bleacher, Jacob E.; Glaze, Lori S.
Journal of volcanology and geothermal research,
02/2013, Letnik:
252
Journal Article
Recenzirano
A field of small (10s of km in diameter) volcanoes in the Syria Planum region of Mars is mapped to determine abundance, distribution, and alignments of vents. These data are used to assess possible ...variations in eruption style across space and time. Each eruption site is assigned a point location. Nearest neighbor and two-point azimuth analyses are conducted to assess the spacing and orientations between vents across the study area. Two vent fields are identified as unique volcanic units along with the previously identified Syria Mons volcano. Superposition relationships and crater retention rates indicate that these three volcanic episodes span ~900Ma, beginning in the early Hesperian and ending in the Early Amazonian. No clear hiatus in eruptive activity is identified between these events, although a progression from eruptions at Syria Mons, to regionally distributed eruptions that form the bulk of the Syria Planum plains, to a final migration of dispersed eruptions to Syria's northwest is identified. Nearest neighbor analyses suggest a non-random distribution among the entire population of Syria Planum, which is interpreted as resulting from the interaction of independent magma bodies ascending through the crust during different stress regimes throughout the region's eruptive history. Two-point azimuth results identify three orientations of enhanced alignments, which match well with radial extensions of three major tectonic centers to the south, east, and northwest of the study area. As such, Syria Planum volcanism evolved from a central vent volcano to dispersed shield field development over several hundred million years, during which the independent magma bodies related to each small volcano interacted to some extent with one or more of at least three buried tectonic patterns in the older crust. These results show a strong relationship between independent mapping efforts of tectonic and volcanic features. Continued integration of volcano-tectonic mapping should provide direct constraints for future geodynamic models of magma production and thermal evolution of the Tharsis province.
► A new catalog of 263 volcanic vents is created for Syria Planum, Mars. ► Spatial analyses and crater age-dating are performed on the vent catalog. ► The center of volcanism of Syria Planum migrates throughout its volcanic history. ► Inter-vent lineaments are aligned with tectonic centers of the Tharsis Province.
We mapped lava flows on the Tharsis Montes (Arsia Mons, Pavonis Mons, and Ascraeus Mons) using High Resolution Stereo Camera images that centrally transect each shield from north to south, covering ...∼20% of each shield's surface. These data were co‐registered to Mars Orbiter Laser Altimeter, Thermal Emission Imaging System, and Mars Orbiter Camera data, enabling lava flow structures and vents to be consistently differentiated across each volcano. Lava flow and vent abundances and relationships are used to provide new insight into the late Amazonian eruptive history of the Tharsis Montes. The volcanoes are divided into their main flanks, rift aprons, and small‐vent fields. Where present on the main flanks, channel‐fed flows always embay tube‐fed flows, indicating a change from long‐lived, stable tube‐forming eruption conditions to shorter‐lived, less stable channel‐forming eruption conditions. Superposition relationships suggest that main flank and rift apron development were likely separated by an eruptive hiatus. The rift aprons, as compared to the main flanks, show higher abundances of tube‐ and channel‐fed flows, and embayment of tube‐fed flows by channel‐fed flows is less consistent. Several trends from the Arsia Mons, to Ascraeus Mons, southwest rift aprons and small‐vent fields were identified, including increased tube abundance, median slope, and number of satellitic eruptive vents and a decrease in channel‐ to tube‐fed flow ratios, apron volumes, and maximum apron elevations. These trends suggest that the most recent volcanic activity at the Tharsis Montes might have originated from a single, shared magma source, possibly marking a change in magma production style from main flank construction.
We used light detection and ranging (LiDAR) data to calculate roughness patterns (homogeneity, mean-roughness, and entropy) for five lava types at two different resolutions (1.5 and 0.1 m/pixel). We ...found that end-member types (ʻaʻā and pāhoehoe) are separable (with 95% confidence) at both scales, indicating that roughness patterns are well suited for analyzing types of lava. Intermediate lavas were also explored, and we found that slabby-pāhoehoe is separable from the other end-members using 1.5 m/pixel data, but not in the 0.1 m/pixel analysis. This suggests that the conversion from pāhoehoe to slabby-pāhoehoe is a meter-scale process, and the finer roughness characteristics of pāhoehoe, such as ropes and toes, are not significantly affected. Furthermore, we introduce the ratio
ENT
HOM
(derived from lava roughness) as a proxy for assessing local lava flow rate from topographic data. High entropy and low homogeneity regions correlate with high flow rate while low entropy and high homogeneity regions correlate with low flow rate. We suggest that this relationship is not directional, rather it is apparent through roughness differences of the associated lava type emplaced at the high and low rates, respectively.
Future piloted space exploration missions will focus more on science than engineering, a change which will challenge existing concepts for flight crew tasking and demand that participants with ...contrasting skills, values, and backgrounds learn to cooperate as equals. In terrestrial space flight analogs such as Desert Research And Technology Studies, engineers, pilots, and scientists can practice working together, taking advantage of the full breadth of all team members' training to produce harmonious, effective missions that maximize the time and attention the crew can devote to science. This paper presents, in a format usable as a reference by participants in the field, a successfully tested crew interaction model for such missions. The model builds upon the basic framework of a scientific field expedition by adding proven concepts from aviation and human space flight, including expeditionary behavior and cockpit resource management, cooperative crew tasking and adaptive leadership and followership, formal techniques for radio communication, and increased attention to operational considerations. The crews of future space flight analogs can use this model to demonstrate effective techniques, learn from each other, develop positive working relationships, and make their expeditions more successful, even if they have limited time to train together beforehand. This model can also inform the preparation and execution of actual future space flights.
► Desert Research And Technology Studies is a simulated space exploration mission. ► Desert RATS crews found effective ways for astronauts and scientists to cooperate. ► They treated the mission as a scientific field study, with concepts from aviation. ► These include cockpit resource management, radio protocol, and operational focus. ► This method may be useful in other space flight analogs and in real space missions.
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