260 research outputs found

    Antartic/Scotia plate convergence off southernmost Chile

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    The southern tip of South America off Chile has suffered a long phase of ocean-continent convergence which has shaped the continental margin through different phases of accretion and tectonic erosion. The present accretionary wedge is a discontinuous geological record of plate convergence and records only part of the accretionary processes resumed after Chile ridge consumption (14 Ma). The structural style of the subduction complex, such as rates of sediment accretion and tectonic erosion, structural vergence, width of the accretionary wedge, taper angle and deformation in the forearc basin, varies along the margin. Large taper values are related to narrow wedges and seaward vergent structures. Low tapers occur where deformation at the toe of the accretionary complex is spread over wide areas and is related both to landward and seaward vergent thrust faults. Seismic data interpretation contributes to define more accurately frontal wedge morphology and geometry of subduction and suggests that different modes of accretion together with tectonic erosion may be active concurrently along the trench at different locations. In areas of subduction driven accretionary processes the majority of trench sediments are involved in accretionary processes and sediments are uplifted and piled up in the form of imbricate thrust sheets. In areas where the wedge is non-accretionary the continental margin shows steeper continental slopes associated with narrow accretionary wedges, more intense sediment disruption and very shallow décollement levels. Variation in structural style and in the geometry of the forearc region setting off Southernmost Chile, has been interpreted as related to the existence of different structural domains: the nature of their boundaries is still unclear mainly for the lack of high resolution bathymetric data. They have been tentatively related to tectonic lineaments belonging to the Magellan Fault system and/or to the character and morphology of the converging plates (lateral heterogeneities, sea-mounts and fracture zones), which produce a segmentation of the margin

    Project HOME (Hydroponic Operations for Mars Exploration)

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    Agriculture in enclosed structures on Mars enables astronauts to conduct extended surface exploration missions. To support these missions, we will evaluate multiple hydroponics systems to grow a complete necessary set of amino acids, vitamins, minerals, fiber, carbohydrates, and nutrients for a balanced diet. The hydroponics systems will be designed in a greenhouse powered solely through solar panels, and the plants will receive the same solar irradiance as the surface of Mars. The light intensity in the greenhouse will be kept at approximately 590 W/m^2 by using a shade cloth to limit the natural light from the sun. This simulates an ambient light collection and reflection system on Mars, illuminating an insulated outdoor system for agriculture. The utilization of a hydroponics system allows for a more effective method of growing superfoods in abstract environments. *Currently in the data collection phase of the research, hope to share some initial findings on discovery day

    Hydroponically Growing a Holistic Superfood Diet for Mars Exploration

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    In “Hydroponically Growing a Holistic Superfood Diet for Mars Exploration,” Project H.O.M.E. members conducted an experiment to help determine ways to provide future astronauts with a complete, balanced diet on a planet that does not receive as much sunlight as Earth. Sending massive amounts of food into space is incredibly expensive, takes up valuable spacecraft area, and is, overall, not a feasible way to provide astronauts with sustenance. Project H.O.M.E. has thus developed a hydroponic system to evaluate the growth and yield of various superfoods - including Moringa Oleifera, goji berries, and kale - under simulated Mars lighting conditions. Data suggests that these three plants are perennial hydroponic crops, which can be grown under reduced illumination, and are candidate food sources for Mars explorers. Based on the hypothesis that the growth of the superfood plants in simulated lighting conditions will be similar to their growth in regular lighting conditions here on Earth, Project H.O.M.E. members created a Dutch bucket, tower garden, and nutrient flow table indoor hydroponics systems to grow superfoods in a solar-powered 8x16ft greenhouse for the past 13 months. In conclusion, this project determined that the growth of superfoods using hydroponics systems would be a preferred farming method for space, demonstrating the incredible potential for future missions to Mars

    Project HOME (Hydroponic Operations for Mars Exploration)

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    This research project is focused on providing future astronauts ways to grow a complete diet on a planet that does not receive as much sunlight as Earth does. We evaluated a deep-water culture indoor hydroponics system to grow Moringa Oleifera, a nutrient- and antioxidant-rich plant with leaves containing all nine essential amino acids. After initial aquaponics growth and 3 prior harvests, the lighting intensity was set to 590 W/m^2 in a twelve hour on/off cycle. This simulates an ambient light collection and reflection system on Mars. 32 plants were harvested 17 times over a 9 month period at regular intervals, when plant heights reached an average of 0.9 m and we found consumable leaf yield averaged 0.18g per plant, per day. Data suggests using Moringa Oleifera as a perennial hydroponic crop is possible under reduced illumination, and is a candidate food source for Mars explorers. Preliminary research has expanded to utilizing natural light, additional plants, three more hydroponic systems, and solar power. Currently, a solar powered 8x12ft greenhouse is being used to hydroponically grow Goji Berries, Moringa Oleifera, Bamboo, Kale, Chia and Sweet Potatoes. Combined, these foods contain a complete set of nutrients needed for a balanced human diet. The greenhouse and solar panels receive 590 W/m^2 by utilizing shade cloths. In conclusion, the project demonstrates that astronauts will have great potential in future missions to Mars to maximize the growth of superfoods using natural light, with a focus on a hydroponics system as the preferred farming method for space

    Evidence of positive tectonic inversion in the north-central sector of the Sicily Channel (Central Mediterranean)

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    In order to unravel the tectonic evolution of the north-central sector of the Sicily Channel (Central Mediterranean), a seismo-stratigraphic analysis of single- and multi-channel seismic reflection profiles has been carried out. This allowed to identify, between 20 and 50 km offshore the central-southern coast of Sicily, a ~80-km-long deformation belt, characterized by a set of WNW\u2013ESE to NW\u2013SE fault segments showing a poly-phasic activity. Within this belt, we observed: i) Miocene normal faults reactivated during Zanclean\u2013Piacenzian time by dextral strike-slip motion, as a consequence of the Africa\u2013Europe convergence; ii) releasing and restraining bend geometries forming well-developed pull-apart basins and compressive structures. In the central and western sectors of the belt, we identified local transpressional reactivations of Piacenzian time, attested by well-defined compressive features like push-up structures and fault-bend anticlines. The reconstruction of timing and style of tectonic deformation suggest a strike-slip reactivation of inherited normal faults and the local subsequent positive tectonic inversion, often documented along oblique thrust ramps. This pattern represents a key for an improved knowledge of the structural style of foreland fold-and-thrust belts propagating in a preexisting extensional domain. With regard to active tectonics and seismic hazards, recent GPS data and local seismicity events suggest that this deformation process could be still active and accomplished through deep-buried structures; moreover, several normal faults showing moderate displacements have been identified on top of the Madrepore Bank and Malta High, offsetting the Late Quaternary deposits. Finally, inside the northern part of the Gela Basin, multiple slope failures, originated during Pleistocene by the further advancing of the Gela Nappe, reveal tectonically induced potential instability processes

    Crustal deformation, active tectonics and seismic potential in the Sicily Channel (Central Mediterranean), along the Nubia–Eurasia plate boundary

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    Based on multidisciplinary data, including seismological and geodetic observations, as well as seismic reflection profiles and gravity maps, we analysed the pattern of crustal deformation and active tectonics in the Sicily Channel, a key observation point to unravel the complex interaction between two major plates, Nubia and Eurasia, in the Mediterranean Sea. Our data highlight the presence of an active ~ 220-km-long complex lithospheric fault system (here named the Lampedusa-Sciacca Shear Zone), approximately oriented N–S, crossing the study area with left-lateral strike-slip deformations, active volcanism and high heat flow. We suggest that this shear zone represents the most active tectonic domain in the area, while the NW–SE elongated rifting pattern, considered the first order tectonic feature, appears currently inactive and sealed by undeformed recent (Lower Pleistocene?) deposits. Estimates of seismological and geodetic moment-rates, 6.58 × 1015 Nm/year and 7.24 × 1017 Nm/year, respectively, suggests that seismicity accounts only for ~ 0.9% of crustal deformation, while the anomalous thermal state and the low thickness of the crust would significantly inhibit frictional sliding in favour of creeping and aseismic deformation. We therefore conclude that a significant amount of the estimated crustal deformation-rate occurs aseismically, opening new scenarios for seismic risk assessments in the region

    Modelling tectonic deformation along the North-Anatolian Fault in the Sea of Marmara

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    Using analogue techniques, we attempted to model the complex tectonic deformation pattern observed along the North-Anatolian Fault in the Sea of Marmara from morpho-bathymetry and seismic reflection images. In particular this paper focuses on the so-called Cinarcik segment of the fault connecting the eastern Izmit segment, which entirely ruptured during the Mw 7.4, 1999 earthquake, to the western segment of the Central High. The Çınarcık segment, potentially loaded after the Izmit earthquake, is expected to rupture during an earthquake occurring in the near future, possibly the next decades, with a high potential to affect the Istanbul metropolitan area. Our analysis suggests that the development of the observed structures accommodating strike-slip, transtensional and transpressional deformations, could be explained by changes in the geometry of fault segments within a right-lateral strike-slip tectonic regime. Tectonic deformations were reproduced in the analogue model by imposing a small (about 10°) and sharp difference in the relative orientations of the strike-slip segments at the edges of a major releasing bend. In the model slower strain accumulation occurs along the analogue of the Çınarcık segment than along the analogue of the Izmit segment of the fault. This would predict a delay for earthquakes triggered by stress transfer between the Izmit and Çınarcık segments. The model further predicts that most of the deformation in the Çınarcık basin is controlled by the sharp changes in the geometry of the fault itself

    Project HOME Hydroponic Operations for Mars Exploration

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    This report considers the challenges NASA, SpaceX, and other private companies will face in the approaching two decades when sending astronauts on missions to Mars. The longest exploration is planned to take place in the 2030\u27s, sending a crew of, at minimum, four astronauts to Mars for a year of research. The research conducted is assisting space exploration companies’ with ways to grow a complete diet on a planet that does not receive enough sunlight. Agriculture in enclosed and buried structures on Mars will enable astronauts to conduct extended surface exploration missions. We evaluated a deep-water culture indoor hydroponics system to grow Moringa oleifera (M. Oleifera), a nutrient- and antioxidant-rich plant with leaves containing all nine essential amino acids. After initial aquaponics growth and 3 prior harvests, the lighting intensity was set to 590 W/m^2 in a twelve hour on/off cycle, in normal indoor atmosphere. This simulates an ambient light collection and reflection system on Mars illuminating an insulated, pressurized underground chamber for agriculture. All plants (N = 32) were harvested 17 times over a 9 month period at regular intervals, when plant heights reached an average of 0.9 m. Consumable leaf yield averaged 0.18 dry g per plant per day. Data suggests that M. Oleifera as a perennial hydroponic crop is possible under reduced illumination, and is a candidate food source for Mars explorers. Preliminary research has expanded to utilizing natural light, five additional plants, three more hydroponic systems, and greenhouse ran entirely by solar power. Currently a solar powered eight by twelve foot greenhouse is being used to hydroponically grow goji berries, M. Oleifera, bamboo, kale, chia, and sweet potatoes. When these foods are combined with each other they contain a complete necessary set of amino acids, vitamins, minerals, fiber, carbohydrates, and nutrients for a balanced human diet. The plants receive 590 W/m^2 by utilizing a shade cloth over the entire greenhouse and the solar panels. In conclusion, the report states that NASA, and alike companies, will obtain valuable stepping stones in future missions to Mars by maximizing the growth of superfoods with utilization of natural light, and a focus on a hydroponics system as the farming method for space

    Tsunami potential source in the eastern Sea of Marmara (NW Turkey), along the North Anatolian Fault system

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    Based on morphobathymetric and seismic reflection data, we studied a large landslide body from the eastern Sea of Marmara (NW Turkey), along the main strand of the North Anatolian Fault, one of the most seismically active geological structures on Earth. Due to its location and dimensions, the sliding body may cause tsunamis in case of failure possibly induced by an earthquake. This could affect heavily the coasts of the Sea of Marmara and the densely populated Istanbul Metropolitan area, with its exposed cultural heritage assets. After a geological and geometrical description of the landslide, thanks to high-resolution marine geophysical data, we simulated numerically possible effects of its massive mobilization along a basal displacement surface. Results, within significant uncertainties linked to dimensions and kinematics of the sliding mass, suggest generation of tsunamis exceeding 15–20 m along a broad coastal sector of the eastern Sea of Marmara. Although creeping processes or partial collapse of the landslide body could lower the associated tsunami risk, its detection stresses the need for collecting more marine geological/geophysical data in the region to better constrain hazards and feasibility of specific emergency plans
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