Sample records for vallis rihards uldis

  1. Uzboi Vallis, Nirgal Vallis, and Luki Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 9 April 2002) This THEMIS image captures two channels (Nirgal Vallis is the smaller sinuous channel on the left and Uzboi Vallis is the larger channel located in the lower right) and Luki Crater located in the upper right. The mouth of Nirgal Vallis appears to be truncated by Uzboi Vallis. This indicates that Nirgal Vallis is an older channel than Uzboi Vallis. The floor of Uzboi Vallis was subsequently bombarded by an asteroid or comet which gouged out the 21 km diameter crater named Luki. Luki is named after a town in the Ukraine. Uzboi is the name of a dry river in Russia. Nirgal is the Babylonian name for Mars. Gullies and alluvial deposits discovered by Mars Global Surveyor are clearly visible on the polar-facing (south) wall and floor of Nirgal Vallis and also in the inner rim of Luki crater. These gullies appear to emanate from a specific layer in the walls. There is a pronounced sparsity of gullies on the equator-ward facing slopes but some are present in this image. The gullies have been proposed to have formed by the subsurface release of water. The western channel wall of Uzboi Vallis does not appear to have the fine-scale gullying as does Nirgal Vallis. However, the western channel wall of Uzboi Vallis does show some evidence of downslope movement (mass wasting). Some patches of dunes are also seen on the channel floor, notably along the edges of the channel floor near the canyon walls. There is also a landslide located along the southern wall of Luki Crater.

  2. Marte Vallis

    NASA Technical Reports Server (NTRS)

    2005-01-01

    16 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the results of catastrophic flooding in Marte Vallis, Mars. Marte is the Spanish word for Mars. Many of the major valleys on the red planet are named for the word for 'Mars' in the various languages of Earth. This image shows just a very small portion of the hundreds-of-kilometers-long Marte Vallis system.

    Location near: 17.4oN, 174.7o Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  3. Bahram Vallis

    NASA Image and Video Library

    2018-04-27

    Today's VIS image shows a section of Bahram Vallis. This channel is located in northern Lunae Planum, south of Kasei Valles. Orbit Number: 71256 Latitude: 21.0762 Longitude: 301.486 Instrument: VIS Captured: 2018-01-06 08:51 https://photojournal.jpl.nasa.gov/catalog/PIA22379

  4. Incision of Licus Vallis, Mars, From Multiple Lake Overflow Floods

    NASA Astrophysics Data System (ADS)

    Goudge, Timothy A.; Fassett, Caleb I.

    2018-02-01

    Licus Vallis is a large valley (>350 km long, >2 km wide, and >150 m deep) that heads at the outlet breach of an 30 km diameter impact crater. We present observations of the geomorphology and topography of this paleolake outlet valley and associated tributary valleys to constrain the history of incision of the Licus Vallis system. Licus Vallis has an abrupt increase in gradient by a factor of approximately 4 along its longitudinal profile, and a knickpoint that drops 200 m over a reach of 2 km approximately 12 km downstream from the valley head. We also describe a set of paired terraces within Licus Vallis, which are continuous for tens of kilometers and define an interior valley >2 km in width. We interpret the geomorphology of Licus Vallis as recording at least two discrete, major episodes of valley incision, both driven by lake overflow floods. The main portion of Licus Vallis formed by overflow flooding from a large ( 103-104 km2) lake contained in an intercrater basin. Subsequently, overflow flooding from a lake within the 30 km diameter impact crater reactivated Licus Vallis, forming a major knickpoint at the valley head and establishing the upstream section of the valley at a lower slope. Farther down the valley, this flood event incised an interior valley bounded by paired terraces. Regional tributary valleys that feed Licus Vallis also have prominent knickpoints, which have retreated farthest for downstream valleys. We conclude that these knickpoints record successive waves of incision that swept up Licus Vallis during lake overflow flooding, with erosion in the main trunk of the valley (from overflow floods) significantly outpacing erosion in the tributary valleys (from regional surface runoff). These observations of Licus Vallis illustrate how lake overflow floods may have provided an important control on the pace of landscape evolution on Mars.

  5. Aquifers In Nirgal Vallis

    NASA Astrophysics Data System (ADS)

    Reiss, D.; Jaumann, R.

    The topographic information provided by the Mars Orbiter Laser Altimeter has been used in combination with the Mars Observer Camera imagery to estimate the topo- graphic position of sapping pits and gully heads on the rim of Nirgal Vallis. Hence Nirgal Vallis is understood to be formed by groundwater sapping (1, 2, 3, 4) an aquifer is proposed as water supply. Gullies in the northern rim of Nirgal Vallis as discovered in Mars Observer Camera (MOC) images (5, 6) proof the existence of such an aquifer. Further evidence for sapping in Nirgal Vallis is demonstrated by short hanging tribu- taries with amphitheater-like heads. The basis of these sapping pits defines the con- tact of aquifer to aquiclude during the valley formation. The gully heads are much deeper under the local surface and the correlation of their topographic position with the valley depth indicate the subsidence of the groundwater level following the ver- tical erosion of the valley. This implies the existence of different groundwater tables over time confined by impermeable layers, whereas the gully head level is the most recent groundwater table which still may be erosional active under the conditions of increasing water pressure and ice barrier failure (5). The occurrence of more than one tilted sapping level at different topographic positions which are time-correlated with the erosional notching of the valley, either indicates different aquifers with litholog- ical aquicludes or a climate controlled subsidence of the permafrost layer acting as confining layer. References: (1) Baker et al., 1992, In: Mars, Univ. of Arizona Press. (2) Carr, 1995, JGR 100, 7479. (3) Malin and Carr, 1999, Icarus, 397, 589. (4) Jaumann and Reiss, 2002, LPSC. (5) Malin and Edgett, 2000, Science, 288, 2330. (6) Malin and Edgett, 2001, JGR 106, 23429.

  6. Kasei Vallis Streamlined Island

    NASA Image and Video Library

    2002-12-13

    Except for the loss of its ring of ejecta, the crater at the leading edge of this streamlined island in Kasei Vallis, imaged here by NASA Mars Odyssey, shows no hint of the catastrophic floods that passed by it. Kasei Vallis is one of several major outflow channel systems that were active over 3 billion years ago. The intense floods scoured the landscape, eroding craters and producing streamlined islands. But in a close-up view, the evidence for these floods is not apparent. This true of the most similar terrestrial example, the channeled scablands of eastern Washington which also were formed by a catastrophic flood. http://photojournal.jpl.nasa.gov/catalog/PIA04022

  7. Crater in Marte Vallis

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-566, 6 December 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a streamlined tail-pointing toward the upper right (northeast)--in the lee of a meteor impact crater in Marte Vallis, a large valley and channel complex southeast and east of the Elysium volcanic region. The fluid that went through Marte Vallis, whether water, mud, lava, or otherwise, created this form as it moved from the lower left (southwest) toward the upper right. The crater is located near 19.0oN, 174.9oW. The image covers an area 3 km (1.9 mi) wide and is illuminated from the left.

  8. Dao Vallis

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    This THEMIS visible image shows Dao Vallis, a large outflow channel that starts on the southeast flank of a large volcano called Hadriaca Patera and runs for 1000 kilometers southwest into the Hellas impact basin. The channel is up to 20 kilometers wide near its source, but narrows downstream. As can be seen in the context image, the part of Dao Vallis imaged by THEMIS is actually one of the most narrow.

    It is believed that Dao Vallis was carved by a combination of surface and subsurface flow. Evidence for both of these processes can be seen in this image. The size of the channel, its steep walls, and the lineations at the bottom of the channel indicate that it was carved by surface flow of water. The erosional morphology near the center of the image, on the northern edge of the channel indicates that groundwater sapping was also a minor process. Subsidence of the surface into the quasi-circular depressions seen in this image is indicative of this process.

    Because the source region of Dao Vallis is the flank of a volcano, it is most likely that the water that carved the channel erupted from the subsurface as geothermal heating by nearby magma melted large amounts of ground ice. Some of this water made it to the surface and carved the channel, while some water flowed below ground and caused the sapping features evident in this THEMIS image.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of

  9. Ares Vallis Polygons

    NASA Image and Video Library

    2002-12-04

    The jumble of eroded ridges and mesas seen in this NASA Mars Odyssey image occurs within Ares Vallis, one of the largest catastrophic outflow channels on the planet. Floods raged through this channel, pouring out into the Chryse Basin to the north. Close inspection of the THEMIS image reveals polygonal shapes on the floor of the channel system. Polygonal terrain on Mars is fairly common although the variety of forms and scales of the polygons suggests multiple modes of origin. Those in Ares Vallis resemble giant desiccation polygons that form in soils on Earth when a moist layer at depth drys out. While polygons can form in icy soils (permafrost) and even lava flows, their presence in a channel thought to have been carved by flowing water is at least consistent with a mode of origin that involved liquid water. http://photojournal.jpl.nasa.gov/catalog/PIA04019

  10. Lobo Vallis

    NASA Image and Video Library

    2018-04-20

    Today's VIS image shows a small portion of Lobo Vallis near where it recombines with Kasei Valles and empties into Chryse Planitia. Kasei Valles is a huge channel system that drained the higher elevations of Tharsis into the low of Chryse Planitia. Orbit Number: 71206 Latitude: 28.9604 Longitude: 303.568 Instrument: VIS Captured: 2018-01-02 06:02 https://photojournal.jpl.nasa.gov/catalog/PIA22374

  11. The Color Wonderland of Mawrth Vallis

    NASA Image and Video Library

    2016-09-08

    There is a candidate landing site in the Mawrth Vallis region for the European Space Agency's ExoMars rover, planned to launch in 2020. This is one of the HiRISE images acquired to evaluate this site. Mawrth Vallis has some of the most spectacular color variations seen anywhere on Mars. This color variability is due to a range of hydrated minerals -- water caused alteration of these ancient deposits -- which is why this site is of interest to study the past habitability of Mars. http://photojournal.jpl.nasa.gov/catalog/PIA21029

  12. Reull Vallis - False Color

    NASA Image and Video Library

    2014-12-18

    The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Reull Vallis.

  13. Shalbatana/Simud Vallis Junction

    NASA Image and Video Library

    2003-01-11

    The sinuous channels and streamlined islands at the junction of Shalbatana and Simud Vallis, seen in this NASA Mars Odyssey image, present an erosional history of the catastrophic floods that scoured the Martian surface hundreds of millions of years ago.

  14. Ares Vallis - False Color

    NASA Image and Video Library

    2014-12-31

    The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of of Ares Vallis.

  15. Mawrth Vallis - False Color

    NASA Image and Video Library

    2015-09-30

    The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows where Mawrth Vallis empties into Chryse Planitia.

  16. Daga Vallis - False Color

    NASA Image and Video Library

    2014-12-19

    The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of Daga Vallis on Eos Mensa.

  17. End of Lethe Vallis

    NASA Image and Video Library

    2010-11-15

    This image from NASA Mars Reconnaissance Orbiter shows the funnel-shaped terminus of Lethe Vallis, a winding channel in the Elysium Planitia region of Mars; the floor is covered in solidified lava and blanketed by a thin layer of light-toned dust.

  18. Ares Vallis - False Color

    NASA Image and Video Library

    2015-09-18

    The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This image from NASA 2001 Mars Odyssey spacecraft shows the beginning of Ares Vallis at the edge of Iani Chaos.

  19. Nirgal Vallis (Released 27 March 2002)

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This THEMIS image shows a sinuous valley network channel with sharp bends cutting across the cratered highlands of the southern hemisphere of Mars. The channel is named Nirgal Vallis, which is from the Babylonian word for 'Mars.' Nirgal Vallis is a channel with a total length of approximately 500 km. It is approximately 6 km wide in this region. Gullies and alluvial deposits discovered by Mars Global Surveyor are clearly visible on the polar-facing (south) wall and floor of Nirgal Vallis. These gullies appear to emanate from a specific layer in the walls. There is a pronounced sparsity of gullies on the equator-ward facing slopes. The gullies have been proposed to have formed by the subsurface release of water. Patches of dunes are also seen on the channel floor, notably along the edges of the channel floor near the canyon walls. There is still debate within the scientific community as to how valley networks themselves form: surface runoff (rainfall/snowmelt) or headward erosion via groundwater sapping. This image is approximately 22 km wide and 60 km in length; north is toward the top.

  20. Marte Vallis Platy Flows

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-442, 4 August 2003

    The Marte Vallis system, located east of Cerberus and west of Amazonis Planitia, is known for its array of broken, platy flow features. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a close-up view of some of these plates; they appear to be like puzzle pieces that have been broken apart and moved away from each other. The Mars science community has been discussing these features for the past several years--either the flows in Marte Vallis are lava flows, or mud flows. In either case, the material was very fluid and had a thin crust on its surface. As the material continued to flow through the valley system, the crust broke up into smaller plates that were then rafted some distance down the valley. This picture is located near 6.9oN, 182.8oW. It is illuminated by sunlight from the left.

  1. A Plateau in Ares Vallis

    NASA Image and Video Library

    2015-01-15

    This channelized area is near the source region of the huge outflow channel, Ares Vallis. It was at the distal end or long-ways down-river-area where the Pathfinder/Sojourner mission landed on 4 July 1997.

  2. Ares Vallis Tributary - False Color

    NASA Image and Video Library

    2014-12-17

    The THEMIS VIS camera contains 5 filters. The data from different filters can be combined to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of a tributary channel that empties into Ares Vallis.

  3. Application of VitaVallis dressing for infected wounds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kirilova, N. V., E-mail: n.kirilova@vitavallis.com; Fomenko, A. N., E-mail: alserova@ispms.tsc.ru; Korovin, M. S., E-mail: msk@ispms.tsc.ru

    Today there is a growing demand for safe and efficient antimicrobial dressings for infected wound treatment. The antimicrobial sorption material for VitaVallis dressings was produced by one-stage oxidation of aluminum nanopowder in water in the presence of fibrous acetylcellulose matrix. Scanning electron microscopy revealed that the material is made up of fibers of diameter 1.5–3.0 µm with adhered agglomerated alumina nanosheets. An antimicrobial study revealed a high inhibitory effect of VitaVallis against the growth of gram-negative (E.coli, P. aeruginosa) and gram-positive (S. aureus) strains. The antimicrobial activity of the dressing against microbial pathogens on the wound surface was demonstrated in inmore » vivo experiments on male rats. The dressing was also tested on volunteer patients. The testing showed reduction of the wound healing period, accelerated cleaning of the infected wound and enhanced tissue regeneration in the wound. The results demonstrate that the VitaVallis dressing can be used for the treatment of deep infected wounds.« less

  4. Ma'adim Vallis From the Top

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is a still from an animation showing the geography of Ma'adim Vallis, a valley or channel that enters Gusev Crater. The view of the crater is from the northwest, which is not the direction from which Spirit approached the crater as it landed.

  5. Age of large volcanism to originate the Vallis Schroteri on the Moon

    NASA Astrophysics Data System (ADS)

    Honda, Chikatoshi; Toguchi, Masashi; Morota, Tomokatsu; Hirata, Naru; Demura, Hirohide; Asada, Noriaki; Kitazato, Kohei; Ogawa, Yoshiko; Terazono, Jun-Ya; Haruyama, Junichi

    The Vallis Schrüteri on the Aristarchus Plateau of the Moon is a meandering negative depres-o sion, as called a sinuous rille. The sinuous rille is located at 26.2 N deg. in latitude and 50.8 W deg. in longitude. This is the largest sinuous rille on the moon, which is 168 km in length, 6 km in width, and 500 m on average in depth (less than 1 km) [Honda et al., 2009]. The sinuous rille has been suggested that the negative depression was produced by an ancient huge lava flow which eroded into the substrate ground. The volume of lava flow to produce the negative depression seemed to be the largest among volcanisms on the Moon. However, an age of this volcanic event is not estimated yet. Therefore, it is important to estimate the formation age of the Vallis Schrüteri for understanding of thermal evolution of the Moon. We utilize the crater chronology method using the crater size-frequency distribution for the age estimation of the sinuous rille, because the ability of suitable high resolution images of Kaguya/TC lead us to measure an accurate diameter of small craters in the sinuous rille. We should remove secondary craters from our measurements to acquire more accurate age estimation. There is the Aristarchus crater, 40 km in diameter, nearby the Vallis Schrüteri, so we eliminated the area blanketed by ejecta from the crater by using the Clementine and Kaguya/MI data and carefully remove the secondary craters showing the herringbone, cluster, chains, and elongated characteristics. We examined areas of the floor of the Vallis Schrüteri, and of southwestern outside of the Aristarchus Plateau which is suspected as the lava pond to produce the Vallis Schrüteri by spectral data. If these areas are originated by same lava flow, no difference of the results of age estimation among the areas. As a result, we estimated the formation age of the floor part of the Vallis Schrüteri, as 2.5 (+0.4, -0.4) Ga, and the age of the lava pond, as 3.1 (+0.3, -0.7) Ga. The results

  6. Mapping and dating based evolution studies of the Niger Vallis outflow channel, Mars

    NASA Astrophysics Data System (ADS)

    Kukkonen, S.; Kostama, V.-P.

    2018-04-01

    Niger Vallis is one of the four large outflow channel systems in the eastern Hellas rim region of Mars. Niger, as well as the other nearby valles, is assumed to have been carved by water and later covered by ice-rich deposits. Thus, it plays a significant role both in the fluvial and glacial evolution of the region. This work presents the photogeological mapping and crater count dating results of the Niger Vallis system achieved based on the images of the ConTeXt (CTX) and High Resolution Imaging Science Experiment (HiRISE) cameras of Mars Reconnaissance Orbiter (MRO). The results show that Niger Vallis formed in at least two stages. The southern branch of Niger Vallis originated from Ausonia Cavus, ∼3.7-3.9 Ga ago, whereas the northern branch formed from Peraea Cavus, ∼3.3-3.4 Ga ago. Both of the time scales correspond to the volcanic activity phases of the nearby highland volcanoes of Tyrrhenus and Hadriacus Montes. The fluvial activity of Niger Vallis was not, however, as intense as the activity of the other nearby outflow channels, and it seems to have weakened soon after the formation of the northern branch. The outflow channel was resurfaced again ∼0.9-1.5 Ga ago, probably by regional fluvial activity. After that, the floor of Niger Vallis was covered by lineated valley fills and corresponding ice-rich deposits, the formation of which ended ∼220-470 Ma ago, or not later than ∼110 Ma ago. Although the origin of the deposits was probably related to contemporary climate conditions, the emplacement of some deposits, or even their formation, may have been contributed by impact events. After lineated valley fill formation, the region was resurfaced several times, probably because of changes in regional climatic or endogenic circumstances.

  7. The Moving Sands of Lobo Vallis

    NASA Image and Video Library

    2018-04-02

    NASA's Mars Reconnaissance Orbiter shows bright ripples line the topography in this region, formed within a past climate. Dark dunes and sand streaks (composed of basaltic sand) have moved and filled lower areas, pushed by more recent winds from the top towards the bottom of this image. Lobo Vallis is named for a river on the Ivory Coast. https://photojournal.jpl.nasa.gov/catalog/PIA22346

  8. Knickpoints and Hanging Valleys of Licus Vallis, Mars

    NASA Astrophysics Data System (ADS)

    Goudge, T. A.; Fassett, C.

    2016-12-01

    Licus Vallis is a 350 km long valley system located along the dichotomy boundary on Mars. The main trunk of the valley is incised 200-700 m into the surrounding terrain. The valley heads at an outlet breach of a shallow, 30 km diameter impact crater, and is also fed by a system of tributaries incised into the plateau surrounding Licus Vallis. Many of the tributary valleys, as well as the main stem of the valley fed by the paleolake outlet, have profiles that are not smoothly graded, but rather have distinct reaches with concave downward topography. These sections are either knickpoints or hanging valleys that develop in response to changes in the effective local base level, changes in climate conditions during incision of the valley, or lithologic boundaries in the substrate. Here we present remote sensing observations from images and topography to test these competing hypotheses and further characterize the evolution of this large valley system. Slope-watershed area relationships for the tributaries and main trunk valley are used to distinguish between knickpoints and hanging valleys. Analysis of orbital images does not reveal any distinct layer above which knickpoints develop, and the elevation of knickpoints show no systematic trends that might be expected of a regional lithologic unit(s). Our preliminary results suggest that the distance of knickpoint retreat is correlated with the position of the tributary valley and not the watershed area. Downstream valleys have retreated the most, suggesting they have had the most time to adjust to lowering of the local base level associated with incision of the main valley. These results are most consistent with a wave of incision sweeping up the valley system as it adjusts to a low base level in the northern plains. This conclusion is also consistent with observations of the incision depth of Licus Vallis, which increases approximately linearly downstream. Understanding this signature of base level control on the incision

  9. Geomorphology of Ma'adim Vallis, Mars,and Associated Paleolake Basins

    NASA Technical Reports Server (NTRS)

    Irwin, Rossman, P., III; Howard, Alan D.; Maxwell, Ted A.

    2004-01-01

    Ma'adim Vallis, one of the largest valleys in the Martian highlands, appears to have originated by catastrophic overflow of a large paleola ke located south of the valley heads. Ma'adim Vallis debouched to Gus ev crater, 900 km to the north, the landing site for the Spirit Mars Exploration Rover. Support for the paleolake overflow hypothesis come s from the following characteristics: (I) With a channel width of 3 km at its head, Ma'adim Vallis originates at two (eastern and western) gaps incised into the divide of the approximately 1.1 M km(exp 2) enc losed Eridania head basin, which suggests a lake as the water source. (2) The sinuous course of Ma'adim Vallis is consistent with overland flow controlled by preexisting surface topography, and structural con trol is not evident or required to explain the valley course. (3) The nearly constant approximately 5 km width of the inner channel through crater rim breaches, the anastomosing course of the wide western tri butary, the migration of the inner channel to the outer margins of be nds in the valley's lower reach, a medial sedimentary bar approximate ly 200 m in height, and a step-pool" sequence are consistent with modeled flows of 1-5 x l0 (exp 6) m(exp 3)/s. Peak discharges were likely higher but are poorly constrained by the relict channel geometry. (4 ) Small direct tributary valleys to Ma'adim Vallis have convex-up lon gitudinal profiles, suggesting a hanging relationship to a valley that was incised quickly relative to the timescales of tributary developm ent. (5) The Eridania basin had adequate volume between the initial d ivide and the incised gap elevations to carve Ma'adim Vallis during a single flood. (6) The Eridania basin is composed of many overlapping , highly degraded and deeply buried impact craters. The floor materials of the six largest craters have an unusually high internal relief ( approximately 1 km) and slope (approximately 0.5-1.5 degrees) among d egraded Martian craters, which are usually

  10. Marte Vallis Channel

    NASA Technical Reports Server (NTRS)

    2004-01-01

    14 September 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of a channel in the Marte Valles outflow system. An old meteor impact crater in the lower left (southwest) corner of the image blocked the erosive fluids that poured through Marte Vallis, creating a streamlined tail in its lee. The materials that flowed through the valley may have been water-rich mud, very fluid lava, or both. The nature of the fluid is still a matter of research and discussion among Mars scientists. This image is located near 12.5oN, 177.5oW. The image covers an area approximately 3 km (1.9 mi) across and is illuminated by sunlight from the left/lower left.

  11. Ares Vallis Polygons

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    This jumble of eroded ridges and mesas occurs within Ares Vallis, one of the largest catastrophic outflow channels on the planet. Floods raged through this channel, portions of which are up to 25 km wide, pouring out into the Chryse Basin to the north. Close inspection of the THEMIS image reveals polygonal shapes on the floor of the channel system. Polygonal terrain on Mars is fairly common although the variety of forms and scales of the polygons suggests multiple modes of origin. Those in Ares Vallis resemble giant desiccation polygons that form in soils on Earth when a moist layer at depth drys out. While polygons can form in icy soils (permafrost) and even lava flows, their presence in a channel thought to have been carved by flowing water is at least consistent with a mode of origin that involved liquid water.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  12. Marte Vallis Textures

    NASA Technical Reports Server (NTRS)

    2006-01-01

    20 March 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows platy flow surfaces in the Marte Vallis region of Mars. The origin of the flows is not well-understood, but as some Mars scientists have suggested, the flows may be the product of low viscosity (very fluid), high temperature volcanic eruptions, or perhaps they are the remains of large-scale mud flows. In either case, the materials are solid and hold a record of small meteor impact craters, thus indicating that they are not composed of ice, as still others have speculated.

    Location near: 6.7oN, 182.0oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  13. An Inverted Crater West of Mawrth Vallis

    NASA Image and Video Library

    2017-11-28

    This image from NASA's Mars Reconnaissance Orbiter (MRO) captures details of an approximately 1-kilometer inverted crater west of Mawrth Vallis. A Context Camera image provides context for the erosional features observed at this site. The location of this HiRISE image is north of the proposed landing ellipse for the ExoMars 2020 rover mission that will investigate diverse rocks and minerals related to ancient water-related activity in this region. Prolonged erosion removed less resistant rocks leaving behind other rocks that stand up locally such as the crater seen here and other nearby remnants. These resistant layers may belong to a phase of volcanism and/or water-related activity that carved Mawrth Vallis and filled in existing craters, and other lower-lying depressions, with darker materials. Erosion has also exposed these layers down to older, more resistant lighter rocks that are clay-bearing. The diversity of exposed bedrock made this location an ideal candidate for exploring a potentially water-rich ancient environment that might have once harbored life. The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 28.7 centimeters (11.3 inches) per pixel (with 1 x 1 binning); objects on the order of 86 centimeters (33.9 inches) across are resolved.] North is up. https://photojournal.jpl.nasa.gov/catalog/PIA22117

  14. Clay Minerals in Mawrth Vallis Region of Mars

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This map showing the location of some clay minerals in of a portion of the Mawrth Vallis region of Mars covers an area about 10 kilometers (6.2 mile) wide. The map is draped over a topographical model that exaggerates the vertical dimension tenfold.

    The mineral mapping information comes from an image taken on Sept. 21, 2007, by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM). Iron-magnesium phyllosilicate is shown in red. Aluminum phyllosyllicate is shown in blue. Hydrated silica and a ferrous iron phase are shown in yellow/green.

    The topographical information comes from the Mars Orbiter Laser Altimeter instrument on NASA's Mars Global Surveyor orbiter.

    Mawrth Vallis is an outflow channel centered near 24.7 degrees north latitude, 339.5 degrees east longitude, in northern highlands of Mars.

    CRISM is one of six science instruments on the Mars Reconnaissance Orbiter. Led by The Johns Hopkins University Applied Physics Laboratory, Laurel, Md., the CRISM team includes expertise from universities, government agencies and small businesses in the United States and abroad. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter.

  15. Modification history of the Harmakhis Vallis outflow channel, Mars, based on CTX-scale photogeologic mapping and crater count dating

    NASA Astrophysics Data System (ADS)

    Kukkonen, S.; Kostama, V.-P.

    2018-01-01

    Harmakhis Vallis is one of the four major outflow channel systems (Dao, Niger, Harmakhis, and Reull Valles) that cut the eastern rim region of the Hellas basin, the largest well-preserved impact structure on Mars. The structure of Harmakhis Vallis and the volume of its head depression, as well as earlier dating studies of the region, suggest that the outflow channel formed in the Hesperian period by collapsing when a large amount of subsurface fluid was released. Thus Harmakhis Vallis, as well as the other nearby outflow channels, represents a significant stage of the fluvial activity in the regional history. On the other hand, the outflow channel lies in the Martian mid-latitude zone, where there are several geomorphologic indicators of past and possibly also contemporary ground ice. The floor of Harmakhis also displays evidence of a later-stage ice-related activity, as the outflow channel has been covered by lineated valley fill deposits and debris apron material. The eastern rim region of the Hellas impact basin has been the subject of numerous geologic mapping studies at various scales and based on different imaging data sets. However, Harmakhis Vallis itself has received less attention and the studies on the outflow channel have focused only on limited parts of the outflow channel or on separated different geologic events. In this work, the Harmakhis Vallis floor is mapped and dated from the head depression to the beginning of the terminus based on the Mars Reconnaissance Orbiter's ConTeXt camera images (CTX; ∼ 6 m/pixel). Our results show that Harmakhis Vallis has been modified by several processes after its formation. Age determinations on the small uncovered parts of the outflow channel, which possibly represent the original floor of Harmakhis, imply that Harmakhis may have experienced fluvial activity only 780-850 ( ± 400-600) Ma ago. The discovered terrace structure instead shows that the on-surface activity of the outflow channel has been periodic

  16. Moon/Mars Landing Commemorative Release: Gusev Crater and Ma'adim Vallis

    NASA Technical Reports Server (NTRS)

    1998-01-01

    On July 20, 1969, the first human beings landed on the Moon. On July 20, 1976, the first robotic lander touched down on Mars. This July 20th-- 29 years after Apollo 11 and 22 years since the Viking 1 Mars landing-- we take a look forward toward one possible future exploration site on the red planet.

    One of the advantages of the Mars Global Surveyor Mars Orbiter Camera (MOC) over its predecessors on the Viking and Mariner spacecraft is resolution. The ability to see-- resolve--fine details on the martian surface is key to planning future landing sites for robotic and, perhaps, human explorers that may one day visit the planet.

    At present, NASA is studying potential landing sites for the Mars Surveyor landers, rovers, and sample return vehicles that are scheduled to be launched in 2001, 2003, and 2005. Among the types of sites being considered for these early 21st Century landings are those with 'exobiologic potential'--that is, locations on Mars that are in some way related to the past presence of water.

    For more than a decade, two of the prime candidates suggested by various Mars research scientists are Gusev Crater and Ma'adim Vallis. Located in the martian southern cratered highlands at 14.7o S, 184.5o W, Gusev Crater is a large, ancient, meteor impact basin that--after it formed--was breached by Ma'adim Vallis.

    Viking Orbiter observations provided some evidence to suggest that a fluid--most likely, water--once flowed through Ma'adim Vallis and into Gusev Crater. Some scientists have suggested that there were many episodes of flow into Gusev Crater (as well as flow out of Gusev through its topographically-lower northwestern rim). Some have also indicated that there were times when Ma'adim Vallis, also, was full of water such that it formed a long, narrow lake.

    The possibility that water flowed into Gusev Crater and formed a lake has led to the suggestion that the materials seen on the floor of this crater--smooth-surfaced deposits

  17. Eruption Constraints for a Young Channelized Lava Flow, Marte Vallis, Mars

    NASA Technical Reports Server (NTRS)

    Therkelsen, J. P.; Santiago, S. S.; Grosfils, E. B.; Sakimoto, S. E. H.; Mendelson, C. V.; Bleacher, J. E.

    2001-01-01

    This study constrains flow rates for a specific channelized lava flow in Marte Vallis, Mars. We measured slope-gradient, channel width, and channel depth. Our results are similar to other recent studies which suggests similarities to long, terrestrial basaltic flow. Additional information is contained in the original extended abstract.

  18. Automated Texture Classification of the Mawrth Vallis Landing Site Region

    NASA Astrophysics Data System (ADS)

    Parente, M.; Bayley, L.; Hunkins, L.; McKeown, N. K.; Bishop, J. L.

    2009-12-01

    Supervised classification techniques have been developed to discriminate geomorphologic units in HiRISE images of Mawrth Vallis on Mars, one of the MSL candidate landing sites. A variety of clay minerals that indicate water was once present have been identified in the ancient bedrock at Mawrth Vallis [1-7]. These clay-rich rocks exhibit distinct surface textures in HiRISE images, where the nontronite-bearing unit consists of two primary textures: 2-5 m irregular inverted polygons and irregular parallel fracture sets ([8,13], Fig. b-c). In contrast, the montmorillonite-bearing unit consists of 0.5-1.5 m regular polygons ([8,13], Fig. e). We also characterized dunes (Fig. d), and the spectrally unremarkable caprock unit (Fig. a). Classification of these textures was performed by extracting discriminatory features from gray-level run length matrices (GLRLMs) [9], gray-level co-occurrence matrices (GLCMs) [10], and semivariograms [11] calculated for small blocks of data in HiRISE images. Preliminary results using an algorithm containing eight of these classification features produced a texture classification technique that is 85 percent accurate. The discriminant analysis (e.g. [12]) classifier we used modeled a linear discriminant function for each class based on the training feature vectors for that class. The test vector with the largest value for its discriminant function was then assigned to each class. We assumed linear functions were acceptable for small training sets and we performed automated selection in order to identify the most discriminative features for the textures in Mawrth Vallis. Continued efforts are underway to test and refine this procedure in order to optimize texture recognition on a broader collection of textures, representing additional surface components from Mawrth Vallis and other landing sites on Mars. [1] Bibring, J.-P., et al. (2005) Science, 307, 1576-1581. [2] Poulet, F., et al. (2005) Nature, 438, 632-627. [3] Bishop, J. L., et al

  19. Rotated Perspective View of Nirgal Vallis

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This is the full-resolution, rotated perspective image of Nirgal Vallis, a subset of PIA00942. Nirgal Vallis is one of a number of canyons called valley networks or runoff channels. Much of the debate concerning the origin of these valleys centers on whether they were formed by water flowing across the surface, or by collapse and upslope erosion associated with groundwater processes. At the resolution of this image, it is just barely possible to discern an interwoven pattern of lines on the highland surrounding the valley, but it is not possible to tell whether this is a pattern of surficial debris (sand or dust), as might be expected with the amount of crater burial seen, or a pattern of drainage channels. With 4X better resolution from its mapping orbit, MOC should easily be able to tell the difference between these two possibilities.

    Launched on November 7, 1996, Mars Global Surveyor entered Mars orbit on Thursday, September 11, 1997. The spacecraft has been using atmospheric drag to reduce the size of its orbit for the past three weeks, and will achieve a circular orbit only 400 km (248 mi) above the surface early next year. Mapping operations begin in March 1998. At that time, MOC narrow angle images will be 5-10 times higher resolution than these pictures.

    Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  20. Phyllosilicate diversity and past aqueous activity revealed at Mawrth Vallis, Mars

    USGS Publications Warehouse

    Bishop, J.L.; Dobrea, E.Z.N.; McKeown, N.K.; Parente, M.; Ehlmann, B.L.; Michalski, J.R.; Milliken, R.E.; Poulet, F.; Swayze, G.A.; Mustard, J.F.; Murchie, S.L.; Bibring, J.-P.

    2008-01-01

    Observations by the Mars Reconnaissance Orbiter/Compact Reconnaissance Imaging Spectrometer for Mars in the Mawrth Vallis region show several phyllosilicate species, indicating a wide range of past aqueous activity. Iron/magnesium (Fe/Mg)-smectite is observed in light-toned outcrops that probably formed via aqueous alteration of basalt of the ancient cratered terrain. This unit is overlain by rocks rich in hydrated silica, montmorillonite, and kaolinite that may have formed via subsequent leaching of Fe and Mg through extended aqueous events or a change in aqueous chemistry. A spectral feature attributed to an Fe2+ phase is present in many locations in the Mawrth Vallis region at the transition from Fe/Mg-smectite to aluminum/silicon (Al/Si)-rich units. Fe2+-bearing materials in terrestrial sediments are typically associated with microorganisms or changes in pH or cations and could be explained here by hydrothermal activity. The stratigraphy of Fe/Mg-smectite overlain by a ferrous phase, hydrated silica, and then Al-phyllosilicates implies a complex aqueous history.

  1. Gullies and Bedrock in Nirgal Vallis

    NASA Image and Video Library

    2015-02-11

    The gullies in this image are within the valley wall of an ancient channel-Nirgal Vallis-a testament to flowing water in Mars' ancient past. However, the formation of gullies are still the subject of much debate with respect to their formation: "wet" vs. "dry" or even "dry" with the aid of some lubricating fluid. Gullies most commonly form in the steep walls of simple craters. Gullies are common even in cold arctic deserts on Earth (e.g., the Haughton impact structure on Devon Island). This suggests that these provocative features can form on a mostly dry Mars that is only sporadically wet. Regardless, these features bear a remarkable resemblance to flowers, including the blossom, petals, stem, and roots. Can you see it too? http://photojournal.jpl.nasa.gov/catalog/PIA19294

  2. Athabasca Vallis Streamlined 'Islands'

    NASA Technical Reports Server (NTRS)

    2002-01-01

    MGS MOC Release No. MOC2-322, 12 December 2002

    Tremendous floods carved these tear drop-shaped landforms in Athabasca Vallis in the Cerberus region, south of the Elysium volcanoes. The orientation of the streamlined forms indicate that the fluid flowed from the right/upper right toward the left/lower left (from the northeast to the southwest). Similar features occur in central and eastern Washington in the northwestern United States. The examples in Washington formed when massive amounts of water rushed across the landscape, scouring a 'channeled scabland' during the last Ice Age, roughly 12,000-13,000 years ago. The features on Mars are much older; while the absolute age cannot be determined, the small impact craters with rayed ejecta patterns on the flood surfaces indicate it must be much, much older than the flood landscape in Washington. This is a mosaic of six Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images acquired in 1999 through 2002. Illumination is from the left. The mosaic covers an area 11.9 km (7.4 mi) by 13.0 km (8.1 mi). The full-size mosaic has a resolution of 4 meters (13 ft) per pixel.

  3. The Mawrth Vallis region of Mars: A potential landing site for the Mars Science Laboratory (MSL) mission.

    PubMed

    Michalski, Joseph R; Jean-PierreBibring; Poulet, François; Loizeau, Damien; Mangold, Nicolas; Dobrea, Eldar Noe; Bishop, Janice L; Wray, James J; McKeown, Nancy K; Parente, Mario; Hauber, Ernst; Altieri, Francesca; Carrozzo, F Giacomo; Niles, Paul B

    2010-09-01

    The primary objective of NASA's Mars Science Laboratory (MSL) mission, which will launch in 2011, is to characterize the habitability of a site on Mars through detailed analyses of the composition and geological context of surface materials. Within the framework of established mission goals, we have evaluated the value of a possible landing site in the Mawrth Vallis region of Mars that is targeted directly on some of the most geologically and astrobiologically enticing materials in the Solar System. The area around Mawrth Vallis contains a vast (>1 × 10⁶ km²) deposit of phyllosilicate-rich, ancient, layered rocks. A thick (>150 m) stratigraphic section that exhibits spectral evidence for nontronite, montmorillonite, amorphous silica, kaolinite, saponite, other smectite clay minerals, ferrous mica, and sulfate minerals indicates a rich geological history that may have included multiple aqueous environments. Because phyllosilicates are strong indicators of ancient aqueous activity, and the preservation potential of biosignatures within sedimentary clay deposits is high, martian phyllosilicate deposits are desirable astrobiological targets. The proposed MSL landing site at Mawrth Vallis is located directly on the largest and most phyllosilicate-rich deposit on Mars and is therefore an excellent place to explore for evidence of life or habitability.

  4. Ancient Martian Lakestands and Fluvial Processes in Iani Chaos: Geology of Light-Toned Layered Deposits and their Relationship to Ares Vallis Outflow Channels

    NASA Astrophysics Data System (ADS)

    Guallini, Luca; Gilmore, Martha; Marinangeli, Lucia; Thomas, Nicolas

    2015-04-01

    Iani Chaos is a ~30,000 square kilometers region that lies at the head of the Ares Vallis outflow channel system. Mapping of Ares Vallis reveals multiple episodes of erosion, probably linked to several discharge events from the Iani Chaos aquifer. We present the first detailed geomorphological map of the Iani region. Five chaos units have been distinguished with varying degrees of modification (primarily by erosion and fracturing), starting from a common terrain (Noachian highlands). We observe a general progressive decrease of their mean elevation from the Mesas, Mesas & Knobs and Hummocky (Hy) terrains to the Knobs and Knobby morphologies. This trend is consistent with an initial collapse of the original surface with an increase of the fracturing and/or of the erosion. Light-toned Layered Deposits (LLD) have been also mapped and described in Iani Chaos. These terrains are clearly distinguished by a marked light-toned albedo, high thermal inertia and a pervasively fractured morphology. LLD both fill the basins made by the collapsed chaotic terrains and are found to be partially modified by the chaos formation. LLD also overlap chaos mounds or are themselves eroded into mounds after deposition. These stratigraphic relationships demonstrate that LLD deposition occurred episodically in the Iani region and throughout the history of the development of the chaos. Water seems to have had an active role in the geological history of Iani. The composition and morphologies of the LLD are consistent with deposition in an evaporitic environment and with erosion by outflows, requiring stable water on the surface. For the first time, we have also mapped and analyzed potential fluvial features (i.e., channels, streamlined islands, terraces, grooved surfaces) on the surface of the LLD. These landforms describe a fluvial system that can be traced from central Iani and linked northward to Ares Vallis. Using topographic data, we have compared the elevation of the LLD and channel

  5. Spectrometer Observations Near Mawrth Vallis

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This targeted image from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) shows a region of heavily altered rock in Mars' ancient cratered highlands. The featured region is just south of Mawrth Vallis, a channel cut by floodwaters deep into the highlands.

    CRISM acquired the image at 1216 UTC (8:16 a.m. EDT) on Oct. 2, 2006, near 25.4 degrees north latitude, 340.7 degrees east longitude. It covers an area about 13 kilometers (8 miles) long and, at the narrowest point, about 9 kilometers (5.6 miles) wide. At the center of the image, the spatial resolution is as good as 35 meters (115 feet) per pixel. The image was taken in 544 colors covering 0.36-3.92 micrometers.

    This image includes four renderings of the data, all map-projected. At top left is an approximately true-color representation. At top right is false color showing brightness of the surface at selected infrared wavelengths. In the two bottom views, brightness of the surface at different infrared wavelengths has been compared to laboratory measurements of minerals, and regions that match different minerals have been colored. The bottom left image shows areas high in iron-rich clay, and the bottom right image shows areas high in aluminum-rich clay.

    Clay minerals are important to understanding the history of water on Mars because their formation requires that rocks were exposed to liquid water for a long time. Environments where they form include soils, cold springs, and hot springs. There are many clay minerals, and which ones form depends on the composition of the rock, and the temperature, acidity, and salt content of the water. CRISM's sister instrument on the Mars Express spacecraft, OMEGA, has spectrally mapped Mars at lower spatial resolution and found several regions rich in clay minerals. The Mawrth Vallis region, in particular, was found to contain iron-rich clay. CRISM is observing these regions at several tens of times higher spatial resolution, to correlate the

  6. Nirgal Vallis

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 16 September 2003

    Upper reaches of Nirgal Vallis. This valley network is one of the longest on Mars and this image captures the sapping morphology (alcoves, stubby tributaries) associated with this channel. However, it is not clear how this channel formed (ground water sapping vs rain/snowmelt surface runoff). The last geomorphic process to occur is the one best preserved but it should be noted that earlier processes may have been modified and or wiped out.

    Image information: VIS instrument. Latitude -27.4, Longitude 314.4 East (45.6 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  7. Formation of outflow channels on Mars: Testing the origin of Reull Vallis in Hesperia Planum by large-scale lava-ice interactions and top-down melting

    NASA Astrophysics Data System (ADS)

    Cassanelli, James P.; Head, James W.

    2018-05-01

    The Reull Vallis outflow channel is a segmented system of fluvial valleys which originates from the volcanic plains of the Hesperia Planum region of Mars. Explanation of the formation of the Reull Vallis outflow channel by canonical catastrophic groundwater release models faces difficulties with generating sufficient hydraulic head, requiring unreasonably high aquifer permeability, and from limited recharge sources. Recent work has proposed that large-scale lava-ice interactions could serve as an alternative mechanism for outflow channel formation on the basis of predictions of regional ice sheet formation in areas that also underwent extensive contemporaneous volcanic resurfacing. Here we assess in detail the potential formation of outflow channels by large-scale lava-ice interactions through an applied case study of the Reull Vallis outflow channel system, selected for its close association with the effusive volcanic plains of the Hesperia Planum region. We first review the geomorphology of the Reull Vallis system to outline criteria that must be met by the proposed formation mechanism. We then assess local and regional lava heating and loading conditions and generate model predictions for the formation of Reull Vallis to test against the outlined geomorphic criteria. We find that successive events of large-scale lava-ice interactions that melt ice deposits, which then undergo re-deposition due to climatic mechanisms, best explains the observed geomorphic criteria, offering improvements over previously proposed formation models, particularly in the ability to supply adequate volumes of water.

  8. Geologic Mapping along the Arabia Terra Dichotomy Boundary: Mawrth Vallis and Nili Fossae, Mars

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III; Crown, David A.

    2009-01-01

    Geologic mapping studies at the 1:1M-scale are being used to assess geologic materials and processes that shape the highlands along the Arabia Terra dichotomy boundary. In particular, this mapping will evaluate the distribution, stratigraphic position, and lateral continuity of compositionally distinct outcrops in Mawrth Vallis and Nili Fossae as identified by spectral instruments currently in orbit. Placing these landscapes, their material units, structural features, and unique compositional outcrops into spatial and temporal context with the remainder of the Arabia Terra dichotomy boundary may provide constraints on: 1) origin of the dichotomy boundary, 2) paleo-environments and climate conditions, and 3) various fluvial-nival modification processes related to past and present volatile distribution and their putative reservoirs (aquifers, lakes and oceans, surface and ground ice) and the influences of nearby volcanic and tectonic features on hydrologic processes in these regions. The results of this work will include two 1:1M scale geologic maps of twelve MTM quadrangles (Mawrth Vallis - 20022, 20017, 20012, 25022, 25017, and 25012; and Nili Fossae - 20287, 20282, 25287, 25282, 30287, 30282).

  9. A View of the Painted Desert Near Mawrth Vallis

    NASA Image and Video Library

    2017-08-07

    The clay-rich terrain surrounding Mawrth Vallis is one of the most scenic regions of Mars, a future interplanetary park, as seen by NASA's Mars Reconnaissance Orbiter. Here, we cut a long, oblique view into strips to see the full color coverage in more compact form. The origin of these altered layers is the subject of continued debates, perhaps to be resolved by a future rover on the surface. We do know that these layers are very ancient, dating back to a time when the environment of Mars was wetter and more habitable, if there were any inhabitants. https://photojournal.jpl.nasa.gov/catalog/PIA21871

  10. Preliminary Geological Map of the Peace Vallis Fan Integrated with In Situ Mosaics From the Curiosity Rover, Gale Crater, Mars

    NASA Technical Reports Server (NTRS)

    Sumner, D. Y.; Palucis, M.; Dietrich, B.; Calef, F.; Stack, K. M.; Ehlmann, B.; Bridges, J.; Dromart, J.; Eigenbrode, J.; Farmer, J.; hide

    2013-01-01

    A geomorphically defined alluvial fan extends from Peace Vallis on the NW wall of Gale Crater, Mars into the Mars Science Laboratory (MSL) Curiosity rover landing ellipse. Prior to landing, the MSL team mapped the ellipse and surrounding areas, including the Peace Vallis fan. Map relationships suggest that bedded rocks east of the landing site are likely associated with the fan, which led to the decision to send Curiosity east. Curiosity's mast camera (Mastcam) color images are being used to refine local map relationships. Results from regional mapping and the first 100 sols of the mission demonstrate that the area has a rich geological history. Understanding this history will be critical for assessing ancient habitability and potential organic matter preservation at Gale Crater.

  11. Geologic map of MTM -45252 and-45257 quadrangles, Reull Vallis region of Mars

    USGS Publications Warehouse

    Mest, Scott C.; Crown, David A.

    2003-01-01

    Mars Transverse Mercator (MTM) quadrangles -45252 and -45257 (latitude 42.5° S. to 47.5°S., longitude 250° W. to 260° W.) cover a portion of the highlands of Promethei Terra east of Hellas basin. The map area consists of heavily cratered ancient highland materials having moderate to high relief, isolated knobs and massifs of rugged mountainous material, and extensive tracts of smooth and channeled plains. Part of the ~1,500-km-long Reull Vallis outflow system is within the map area. The area also contains surficial deposits, such as the prominent large debris aprons that commonly surround highland massifs. Regional slopes are to the west, toward the Hellas basin, as indicated by topographic maps of Mars. Approximately 60 percent of the surface of Mars is covered by rugged, heavily cratered terrains believed to represent the effects of heavy bombardment in the inner solar system about 4.0 billion years ago. Much of this terrain, including that within the map area, records a long history of modification by tectonism, fluvial processes, mass wasting, and eolian activity. The presence of fluvial features to the east of Hellas basin, including Reull Vallis and other smaller channels, has significant implications for past environmental conditions. The degraded terrains surrounding Hellas basin provide constraints on the role and timing of volatile-driven activity in the evolution of the highlands. Current photogeologic mapping at 1:500,000 scale (see also Mest and Crown, 2002) from analysis of Viking Orbiter images complements previous geomorphic studies of Reull Vallis and other highland outflow systems, drainage networks, and highland debris aprons, as well as regional geologic mapping studies and geologic mapping of Hellas basin as a whole at 1:5,000,000 scale. Viking Orbiter image coverage of the map area generally ranges from 160 to 220 m/pixel; the central part of the map area is covered by higher resolution images of about 47 m/pixel. Crater size

  12. Geologic Mapping along the Arabia Terra Dichotomy Boundary: Mawrth Vallis and Nili Fossae, Mars: Introductory Report

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III; Crown, David A.

    2008-01-01

    Geologic mapping studies at the 1:1M-scale will be used to characterize geologic processes that have shaped the highlands along the Arabia Terra dichotomy boundary. In particular, this mapping will evaluate the distribution, stratigraphic position, and lateral continuity of compositionally distinct outcrops in Mawrth Vallis and Nili Fossae as identified by spectral instruments currently in orbit. Placing these landscapes, their material units, structural features, and unique compositional outcrops into spatial and temporal context with the remainder of the Arabia Terra dichotomy boundary will provide the ability to: 1) further test original dichotomy formation hypotheses, 2) constrain ancient paleoenvironments and climate conditions, and 3) evaluate various fluvial-nival modification processes related to past and present volatile distribution and their putative reservoirs (aquifers, lakes and oceans, surface and ground ice) and the influences of nearby volcanic and tectonic features on hydrologic processes in these regions. The result will be two 1:1M scale geologic maps of twelve MTM quadrangles (Mawrth Vallis - 20022, 20017, 20012, 25022, 25017, and 25012; and Nili Fossae - 20287, 20282, 25287, 25282, 30287, 30282).

  13. Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington

    NASA Technical Reports Server (NTRS)

    Golombek, M. P. (Editor); Edgett, K. S. (Editor); Rice, J. W. , Jr. (Editor)

    1995-01-01

    Mars Pathfinder will place a single lander on the surface of Mars on July 4, 1997, following a December 1996 launch. As a result of the very successful first Mars Pathfinder Landing Site Workshop, the project has selected the Ares Vallis outflow channel in Chryse Planitia as the landing site. This location is where a large catastrophic outflow channel debouches into the northern lowlands. A second workshop and series of field trips, entitled Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington, were held in Spokane and Moses Lake, Washington. The purpose of the workshop was to provide a focus for learning as much as possible about the Ares Vallis region on Mars before landing there. The rationale is that the more that can be learned about the general area prior to landing, the better scientists will be able interpret the observations made by the lander and rover and place them in the proper geologic context. The field trip included overflights and surface investigations of the Channeled Scabland (an Earth analog for the martian catastrophic outflow channels), focusing on areas particularly analogous to Ares Vallis and the landing site. The overflights were essential for placing the enormous erosional and depositional features of the Channeled Scabland into proper three-dimensional context. The field trips were a joint educational outreach activity involving K-12 science educators, Mars Pathfinder scientists and engineers, and interested scientists from the Mars scientific community. Part 1 of the technical report on this workshop includes a description of the Mars Pathfinder mission, abstracts accepted for presentation at the workshop, an introduction to the Channeled Scabland, and field trip guides for the overflight and two field trips. This part, Part 2, includes the program for the workshop, summaries of the workshop technical sessions, a summary of the field trips and ensuing

  14. Near-Surface Geologic Units Exposed Along Ares Vallis and in Adjacent Areas: A Potential Source of Sediment at the Mars Pathfinder Landing Site

    NASA Technical Reports Server (NTRS)

    Treiman, Allan H.

    1997-01-01

    A sequence of layers, bright and dark, is exposed on the walls of canyons, impact craters and mesas throughout the Ares Vallis region, Chryse Planitia, and Xanthe Terra, Mars. Four layers can be seen: two pairs of alternating dark and bright albedo. The upper dark layer forms the top surface of many walls and mesas. The upper dark-bright pair was stripped as a unit from many streamlined mesas and from the walls of Ares Valles, leaving a bench at the top of the lower dark layer, approximately 250 m below the highland surface on streamlined islands and on the walls of Ares Vallis itself. Along Ares Vallis, the scarp between the highlands surface and this bench is commonly angular in plan view (not smoothly curving), suggesting that erosion of the upper dark-bright pair of layers controlled by planes of weakness, like fractures or joints. These near-surface layers in the Ares Vallis area have similar thicknesses, colors, and resistances to erosion to layers exposed near the tops of walls in Valles Marineris (Treiman et al.) and may represent the same pedogenic hardpan units. From this correlation, and from analogies with hardpans on Earth, the light-color layers may be cemented by calcite or gypsum. The dark layers are likely cemented by an iron-bearing mineral. Mars Pathfinder instruments should permit recognition and useful analyses of hardpan fragments, provided that clean uncoated surfaces are accessible. Even in hardpan-cemented materials, it should be possible to determine the broad types of lithologies in the Martian highlands. However, detailed geochemical modeling of highland rocks and soils may be compromised by the presence of hardpan cement minerals.

  15. Ma'adim Vallis Estuarine Delta in Elysium Basin and Its Relevance as a Landing Site for Exobiology Exploration on Mars

    NASA Technical Reports Server (NTRS)

    Grin, E. A.; Cabrol, N. A.

    1998-01-01

    The debouche of Ma'adim Vallis in the Elysium Basin generated a transitional transported sediment structure, which planimetric shape is controlled by the enclosing topography of a deep reentrant gulf of the Basin into the highland. We defined it as an estuarine delta. The location and the importance of this estuarine delta is supported by the theoretical model of graded profile constructed for Ma'adim Vallis, and by two approaches: (i) the reconstruction of Ma'adim Vallis downstream course from Gusev to Elysium Basin, and (ii) the survey of the sediment deposit in the alleged estuary. The longitudinal graded profile of Ma'adim Vallis finds its base-level in the Elysium Basin, at a about 1000 m elevation, which is in agreement with the observed Basin shoreline. This model is supported by observational evidence of flow between the northern rim of Gusev crater, and the Elysium Basin shoreline. This downstream course of Ma'adim Vallis can be divided into three hydrogeologic regions. into three hydrogeologic regions. (a) The first region is a flooded plain (Zephiria Mensae), consisting in chaotic terrain formed by highland rocks, and disintegrated lava of the western flank of Apollinaris. Morphologic indicators of the flood process are: (1) the sediment deposit over the Gusev crater northern rim that reflects the overspilling of the crater-lake water through a 40-km wide gap provided by an ancient impact crater, (2) the tear-drop shaped feature on the northeastern flank of Apollinaris Patera, and (3) the chaotic terrain that suggest the emergence of ground water generated by the seepage of the crater lake through high-permeable broken rampart material. This underground water circulation sustained by the hydrostatic pressure of the crater-lake has likely generated a hydrothermal system in the volcanic environment of Apollinaris Patera. The stratigraphy of the flooded area is identified as Hesperian age, with occurrences of Noachian hilly individual features, and as

  16. Tinto Vallis Fluvial Channel

    NASA Technical Reports Server (NTRS)

    2004-01-01

    <

    [figure removed for brevity, see original site]

    This night time IR image shows a small fluvial channel located near Tinto Vallis. These channels are northeast of Tyrrhena Patera and its related lava flows. Tyrrhena Patera is one of the larger volcanic complexs in the southern hemisphere of Mars. Small channels are easy to see in nighttime IR, with the cold channel floor (dark) contrasting from the warmer (bright) surroundings.

    NOTE: in nighttime images North is to the bottom of the image.

    Image information: IR instrument. Latitude -24.6, Longitude 349.7 East (10.3 West). 100 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  17. Discovery of jarosite within the Mawrth Vallis region of Mars: Implications for the geologic history of the region

    NASA Astrophysics Data System (ADS)

    Farrand, William H.; Glotch, Timothy D.; Rice, James W.; Hurowitz, Joel A.; Swayze, Gregg A.

    2009-12-01

    Analysis of visible to near infrared reflectance data from the MRO CRISM hyperspectral imager has revealed the presence of an ovoid-shaped landform, approximately 3 by 5 km in size, within the layered terrains surrounding the Mawrth Vallis outflow channel. This feature has spectral absorption features consistent with the presence of the ferric sulfate mineral jarosite, specifically a K-bearing jarosite (KFe 3(SO 4) 2(OH) 6). Terrestrial jarosite is formed through the oxidation of iron sulfides in acidic environments or from basaltic precursor minerals with the addition of sulfur. Previously identified phyllosilicates in the Mawrth Vallis layered terrains include a basal sequence of layers containing Fe-Mg smectites and an upper set of layers of hydrated silica and aluminous phyllosilicates. In terms of its fine scale morphology revealed by MRO HiRISE imagery, the jarosite-bearing unit has fracture patterns very similar to that observed in Fe-Mg smectite-bearing layers, but unlike that observed in the Al-bearing phyllosilicate unit. The ovoid-shaped landform is situated in an east-west bowl-shaped depression superposed on a north sloping surface. Spectra of the ovoid-shaped jarosite-bearing landform also display an anomalously high 600 nm shoulder, which may be consistent with the presence of goethite and a 1.92 μm absorption which could indicate the presence of ferrihydrite. Goethite, jarosite, and ferrihydrite can be co-precipitated and/or form through transformation of schwertmannite, both processes generally occurring under low pH conditions (pH 2-4). To date, this location appears to be unique in the Mawrth Vallis region and could represent precipitation of jarosite in acidic, sulfur-rich ponded water during the waning stages of drying.

  18. Discovery of jarosite within the Mawrth Vallis region of Mars: Implications for the geologic history of the region

    USGS Publications Warehouse

    Farrand, W. H.; Glotch, T.D.; Rice, J. W.; Hurowitz, J.A.; Swayze, G.A.

    2009-01-01

    Analysis of visible to near infrared reflectance data from the MRO CRISM hyperspectral imager has revealed the presence of an ovoid-shaped landform, approximately 3 by 5 km in size, within the layered terrains surrounding the Mawrth Vallis outflow channel. This feature has spectral absorption features consistent with the presence of the ferric sulfate mineral jarosite, specifically a K-bearing jarosite (KFe3(SO4)2(OH)6). Terrestrial jarosite is formed through the oxidation of iron sulfides in acidic environments or from basaltic precursor minerals with the addition of sulfur. Previously identified phyllosilicates in the Mawrth Vallis layered terrains include a basal sequence of layers containing Fe-Mg smectites and an upper set of layers of hydrated silica and aluminous phyllosilicates. In terms of its fine scale morphology revealed by MRO HiRISE imagery, the jarosite-bearing unit has fracture patterns very similar to that observed in Fe-Mg smectite-bearing layers, but unlike that observed in the Al-bearing phyllosilicate unit. The ovoid-shaped landform is situated in an east-west bowl-shaped depression superposed on a north sloping surface. Spectra of the ovoid-shaped jarosite-bearing landform also display an anomalously high 600 nm shoulder, which may be consistent with the presence of goethite and a 1.92 ??m absorption which could indicate the presence of ferrihydrite. Goethite, jarosite, and ferrihydrite can be co-precipitated and/or form through transformation of schwertmannite, both processes generally occurring under low pH conditions (pH 2-4). To date, this location appears to be unique in the Mawrth Vallis region and could represent precipitation of jarosite in acidic, sulfur-rich ponded water during the waning stages of drying. ?? 2009 Elsevier Inc. All rights reserved.

  19. Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington

    NASA Technical Reports Server (NTRS)

    Golombek, M. P. (Editor); Edgett, K. S. (Editor); Rice, J. W., Jr. (Editor)

    1995-01-01

    This volume, the first of two comprising the technical report for this workshop, contains papers that have been accepted for presentation at the Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region, September 24-30, 1995, in Spokane, Washington. The Mars Pathfinder Project received a new start in October 1993 as one of the next missions in NASA's long-term Mars exploration program. The mission involves landing a single vehicle on the surface of Mars in 1997. The project is one of the first Discovery-class missions and is required to be a quick, low-cost mission and achieve a set of significant but focused engineering, science, and technology objectives. The primary objective is to demonstrate a low-cost cruise, entry, descent, and landing system required to place a payload on the martian surface in a safe, operational configuration. Additional objectives include the deployment and operation of various science instruments and a microrover. Pathfinder paves the way for a cost-effective implementation of future Mars lander missions. Also included in this volume is the field trip guide to the Channeled Scabland and Missoula Lake Break-out. On July 4, 1997, Mars Pathfinder is scheduled to land near 19.5 deg N, 32.8 deg W, in a portion of Ares Vallis. The landing ellipse covers a huge (100 x 200 km) area that appears to include both depositional and erosional landforms created by one or more giant, catastrophic floods. One of the best known terrestrial analogs to martian outflow channels (such as Ares Vallis) is the region known as the Channeled Scabland. The field trip guide describes some of the geomorphological features of the Channeled Scabland and adjacent Lake Missoula break-out area near Lake Pend Oreille, Idaho.

  20. Geologic map of MTM -40252 and -40257 quadrangles, Reull Vallis region of Mars

    USGS Publications Warehouse

    Mest, Scott C.; Crown, David A.

    2002-01-01

    Mars Transverse Mercator (MTM) quadrangles -40252 and -40257 cover a portion of the highlands of Promethei Terra northeast of the Hellas basin. The map area consists of heavily cratered ancient highland materials of moderate to high relief, isolated knobs and massifs of rugged mountainous materials, extensive tracts of smooth and channeled plains, and other surficial deposits. Reull Vallis, an approximately 1,500 km-long outflow channel system, cuts through the southeast corner of the map area. Regional slopes are to the southwest, toward the Hellas basin, as indicated by Martian topographic maps and the orientations of channels along the northeast rim of the Hellas basin. The Martian highlands cover more than 60 percent of the planet's surface and are primarily in the southern hemisphere. Most of the highlands consist of rugged, densely cratered terrains believed to represent the final phase of heavy bombardment in the inner solar system about 4.0 billion years ago. Parts of the Martian highlands show evidence of extensive degradation and modification. The map area shows landforms created by numerous geologic processes, including tectonism, fluvial activity, and mass wasting. The occurrence of fluvial features, such as outflow channels and valley networks, has significant implications for past Martian conditions. Determining the geology of the highlands northeast of the Hellas basin provides a better understanding of the role and timing of volatile-driven activity in the evolution of the highlands. Photogeologic mapping at 1:500,000 scale from analysis of Viking Orbiter images complements geomorphic studies of Reull Vallis and other highland outflow systems, of drainage networks, and of highland debris aprons and regional geologic mapping studies of the highlands at the 1:2,000,000 scale and 1:1,000,000 scale. Crater size-frequency distributions have been compiled to constrain the relative ages of geologic units and determine the timing and extents of the observed

  1. Fluvial processes in Ma'adim Vallis and the potential of Gusev crater as a high priority site

    NASA Technical Reports Server (NTRS)

    Cabrol, Nathalie; Landheim, Ragnild; Greeley, Ronald; Farmer, Jack

    1994-01-01

    According to exobiology site selection criteria for Mars, the search for potential extinct/extant water dependent life should focus on sites were water flowed and ponded. The Ma'adim Vallis/Gusev crater system is of high priority for exobiology research, because it appears to have involved long term flooding, different periods and rates of sedimentation, and probable episodic ponding. The topics covered include the following: evidence of nonuniform fluvial processes and early overflooding of the plateau and ponding.

  2. A Streamlined Form in Lethe Vallis

    NASA Image and Video Library

    2016-09-08

    This image shows a portion of Lethe Vallis, an outflow channel that also transported lava. Another investigation of this area (Balme et al., 2011) discovered a repeat pattern of dune-like forms in the channel interpreted as fluvial dunes (or, giant current ripples) which are dunes formed by flowing water. This is one of only a few places on Mars where these pristine-appearing landforms have been identified. The channel formed by catastrophic floods, during which it produced the prominent crater-cored, teardroped-shaped island in the middle. The island has the blunter end pointing upstream and the long tail pointing downstream. Both the island and the fluvial dunes were formed by these extreme floods and their size is an indicator of the enormous discharges required to create them. The margins of the channel also show the terminal front of a pristine lava flow unit that inundated the channel from the south and the dunes show the remnants of another older lava flow. The top of the island displays polygonal patterned ground texture, which is a characteristic of periglacial processes in ice-rich ground. The dark materials from the channel and island walls are probably dark sand being eroded from an underlying horizontal basaltic (lava) layer. The crater at the core of the island has elongated dunes and reticulate dust ridges inside. This single image thus contains features formed by periglacial, volcanic, fluvial, impact, aeolian and mass wasting processes, all in one place. http://photojournal.jpl.nasa.gov/catalog/PIA21039

  3. The sinuous ridge and channel network within Rahway Vallis and the wider contextual study of the surrounding Rahway Basin, Mars.

    NASA Astrophysics Data System (ADS)

    Ramsdale, Jason; Balme, Matthew; Conway, Susan; Gallagher, Colman

    2014-05-01

    Rahway Vallis is a previously identified shallow v-shaped valley network in the Mars Orbiter Laser Altimeter data, located at 10°N 175°E, within the Cerberus Plains in the Elysium Planitia region of Mars. Rahway Vallis is situated in low-lying terrain bounded to west, north and east by older highlands, and to the south by the flood-carved channel system Marte Vallis. Here we present a study of the low-lying area in which Rahway Vallis sits, which we refer to as the "Rahway basin". The floor of the Rahway basin is extremely flat (sloping at 0.02° south-east) and hosts a branching network of ridge and channel systems. The aim of this project is to determine the genesis of these branching forms, in particular to test the hypothesis that they are glaciofluvial in origin. Using topographic cross-profiles of the channels that are identifiable in CTX 6 m/pixel images, we have found that they are set within broader v-shaped valley that has almost no morphological expression. These valleys have a convex-up, shallow (around 15 metres vertically compared to several kilometres in the horizontal) V-shaped profiles that are consistent in form across the whole Rahway Basin. Long profiles show the channels to deepen with respect to the bank height downslope. Both channels and valley show a consistent downhill gradient from west to east. The channels typically widen down-slope and increase in width at confluences. If these are water-cut channels, they reach Strahler stream orders of 4, consistent with a contributory network with multiple sources. Associated with the channels are sinuous ridges, typically several kilometres long, 20 m across, with heights on the order of 10 m. They sometimes form branching networks leading into the channels but also form individually and parallel to the channels. Possible explanations for the sinuous ridges include inverted fluvial channels and eskers. However despite looking through ca. 250 CTX images across the Rahway basin, no other glacial

  4. Kasei Vallis of Mars: Dating the Interplay of Tectonics and Geomorphology

    NASA Technical Reports Server (NTRS)

    Wise, D. U.

    1985-01-01

    Crater density age dates on more than 250 small geomorphic surfaces in the Kasei Region of Mars show clusterings indicative of times of peak geomorphic and tectonic activity. Kasei Vallis is part of a 300 km wide channel system breaching a N-S trending ancient basement high (+50,000 crater age) separating the Chryse Basin from the Tharsis Volcanic Province of Mars. The basement high was covered by a least 3 groups of probable volcanic deposits. Major regional fracturing took place at age 4,000 to 5,000 and was immediately followed by deposition of regional volcanics of the Fesenkov Plains (age 3,000 to 4,200). Younger clusterings of dates in the 900 to 1,500 and 500 to 700 range represent only minor modification of the basic tectonic geomorphic landform. The data suggest that Kasei gap is a structurally controlled breach of a buried ridge by a rather brief episode of fluvial activity.

  5. Geologic Mapping of MTM -30247, -35247 and -40247 Quadrangles, Reull Vallis Region, Mars

    NASA Technical Reports Server (NTRS)

    Mest, S. C.; Crown, D. A.

    2009-01-01

    Geologic mapping of MTM -30247, -35247, and -40247 quadrangles is being used to characterize Reull Vallis (RV) and to determine the history of the eastern Hellas region of Mars. Studies of RV examine the roles and timing of volatile-driven erosional and depositional processes and provide constraints on potential associated climatic changes. This study complements earlier investigations of the eastern Hellas region, including regional analyses [1-6], mapping studies of circum-Hellas canyons [7-10], and volcanic studies of Hadriaca and Tyrrhena Paterae [11-13]. Key scientific objectives include 1) characterizing RV in its "fluvial zone," 2) analysis of channels in the surrounding plains and potential connections to and interactions with RV, 3) examining young, presumably sedimentary plains along RV, and 4) determining the nature of the connection between the segments of RV.

  6. Solar Conjunction Ends: Nirgal Vallis

    NASA Technical Reports Server (NTRS)

    2004-01-01

    28 September 2004 For the past several weeks, Mars was on the other side of the Sun relative to Earth. During this period, known as solar conjunction, radio communication with spacecraft orbiting and roving on Mars was limited. As is always done during solar conjunction, on 7 September 2004, the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) was turned off. On Saturday, 25 September 2004, the MOC team gathered at Malin Space Science Systems to command the instrument to turn back on again. After a successful turn-on, MOC acquired its first narrow angle camera image, shown here, on orbit 24808 (24,808th orbit since the start of the Mapping phase of the MGS mission in March 1999).

    The 25 September image shows a portion of Nirgal Vallis, an ancient valley system in the Mare Erythraeum region of Mars. The valley floor is covered by large, ripple-like bedforms created by wind. This early southern winter image is located near 27.4oS, 42.9oW, and covers an area approximately 3 km (1.9 mi) across. Sunlight illuminates the scene from the upper left.

    This was the 4th solar conjunction period that MGS and MOC have been through since the spacecraft reached the red planet in September 1997. The four solar conjunction periods, where MOC was turned off, were:

    First solar conjunction: 29 April - 1 June 1998 Second solar conjunction: 22 June - 12 July 2000 Third solar conjunction: 1 August - 18 August 2002 Fourth solar conjunction: 7 September - 25 September 2004.

    In late October, MGS MOC will mark the start of its fourth Mars year since the beginning of the Mapping Phase of the mission in March 1999. MGS and MOC have already been orbiting Mars for more than 4 Mars years, including the pre-Mapping aerobrake and science phasing orbit insertion periods.

  7. Mineralogy of Layered Outcrops at Mawrth Vallis and Implications for Early Aqueous Geochemistry on Mars

    NASA Technical Reports Server (NTRS)

    Bishop, J. L.; Gross, C.; Rampe, E. B.; Wray, J. J.; Parente, M.; Horgan, B.; Loizeau, D.; Viviano-Beck, C. E.; Clark, R. N.; Seelos, F. P.; hide

    2016-01-01

    Recently developed CRISM parameters and newly available DTMs are enabling refined characterization of the mineralogy at Mawrth Vallis. A stratigraphy including 5 units is mapped using HRSC DTMs across 100s of kms and using HiRISE DTMs across 100s of meters. Transitions in mineralogic units were characterized using spectral properties and surface morphology. The observations point to an ancient wet and warm geologic record that formed the thick nontronite unit, a period of wet/dry cycling to create acid alteration, followed by leaching or pedogenesis to result in Al-phyllosilicates, and finally a drier, colder climate that left the altered ash in the form of nanophase aluminosilicates, rather than crystalline clays.

  8. The Importance of Lake Overflow Floods for Early Martian Landscape Evolution: Insights From Licus Vallis

    NASA Technical Reports Server (NTRS)

    Goudge, T. A.; Fassett, C. I.

    2017-01-01

    Open-basin lake outlet valleys are incised when water breaches the basin-confining topography and overflows. Outlet valleys record this flooding event and provide insight into how the lake and surrounding terrain evolved over time. Here we present a study of the paleolake outlet Licus Vallis, a >350 km long, >2 km wide, >100 m deep valley that heads at the outlet breach of an approx.30 km diameter impact crater. Multiple geomorphic features of this valley system suggest it records a more complex evolution than formation from a single lake overflow flood. This provides unique insight into the paleohydrology of lakes on early Mars, as we can make inferences beyond the most recent phase of activity..

  9. Geologic Mapping of MTM -30247, -35247 and -40247 Quadrangles, Reull Vallis Region of Mars

    NASA Technical Reports Server (NTRS)

    Mest, S. C.; Crown, D. A.

    2008-01-01

    Geologic mapping and stratigraphic analyses of MTM -30247, -35247, and -40247 quadrangles are being used to characterize the Reull Vallis (RV) system and to determine the history of the eastern Hellas region of Mars. Studies of RV examine the roles and timing of volatile-driven erosional and depositional processes and provide constraints on potential associated climatic changes. This study complements earlier investigations of the eastern Hellas region, including regional analyses [1-6], mapping studies of circum-Hellas canyons [7-10], and volcanic studies of Hadriaca and Tyrrhena Paterae [11-13]. Key scientific objectives for these quadrangles include 1) characterization of RV in its "fluvial zone," 2) analysis of channels in the surrounding plains and potential connections to and interactions with RV, 3) examination of young (?), presumably sedimentary plains along RV that embay the surrounding highlands, and 4) determination of the nature of the connection between segments 1 and 2 of RV.

  10. Characterization of phyllosilicates observed in the central Mawrth Vallis region, Mars, their potential formational processes, and implications for past climate

    USGS Publications Warehouse

    McKeown, N.K.; Bishop, J.L.; Noe Dobrea, E.Z.; Ehlmann, B.L.; Parente, M.; Mustard, J.F.; Murchie, S.L.; Swayze, G.A.; Bibring, J.-P.; Silver, E.A.

    2009-01-01

    Mawrth Vallis contains one of the largest exposures of phyllosilicates on Mars. Nontronite, montmorillonite, kaolinite, and hydrated silica have been identified throughout the region using data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM). In addition, saponite has been identified in one observation within a crater. These individual minerals are identified and distinguished by features at 1.38-1.42, ???1.91, and 2.17-2.41 ??m. There are two main phyllosilicate units in the Mawrth Vallis region. The lowermost unit is nontronite bearing, unconformably overlain by an Al-phyllosilicate unit containing montmorillonite plus hydrated silica, with a thin layer of kaolinite plus hydrated silica at the top of the unit. These two units are draped by a spectrally unremarkable capping unit. Smectites generally form in neutral to alkaline environments, while kaolinite and hydrated silica typically form in slightly acidic conditions; thus, the observed phyllosilicates may reflect a change in aqueous chemistry. Spectra retrieved near the boundary between the nontronite and Al-phyllosilicate units exhibit a strong positive slope from 1 to 2 ??m, likely from a ferrous component within the rock. This ferrous component indicates either rapid deposition in an oxidizing environment or reducing conditions. Formation of each of the phyllosilicate minerals identified requires liquid water, thus indicating a regional wet period in the Noachian when these units formed. The two main phyllosilicate units may be extensive layers of altered volcanic ash. Other potential formational processes include sediment deposition into a marine or lacustrine basin or pedogenesis. Copyright 2009 by the American Geophysical Union.

  11. Ponding, draining and tilting of the Cerberus Plains; a cryolacustrine origin for the sinuous ridge and channel networks in Rahway Vallis, Mars

    NASA Astrophysics Data System (ADS)

    Ramsdale, J. D.; Balme, M. R.; Conway, S. J.; Gallagher, C.

    2015-06-01

    Rahway Vallis sits within a shallow basin (the "Rahway basin") in the Cerberus Plains of Mars containing a branching network of channels converging on the basin floor. Using topographic cross-profiles of the channels we have found that they are set within broader, subtly-expressed, valleys. These valleys are shallow (around 15 m vertically compared to several kilometres in the horizontal) and have convex to rectilinear slope profiles that are consistent in form across the whole Rahway basin. Both channels and valleys descend and deepen consistently from west to east. The channels typically widen down-slope and increase in width at confluences. The morphology and topology of this channel system are consistent with formation by contributory fluid flow, generated from many distributed sources. The transition between the older heavily cratered terrain and the floor of the Rahway basin is bounded by near-horizontal continuous topographic terraces. Plotting the elevation of the terraces shows that they conform to a plane with a height difference of around 100 m east to west for the 300 km width of the Rahway basin. We calculate that the volume of material needed to fill the topography up to the level of the plane best fit by the terraces is ∼1500 km3. Bordering the channels are sinuous ridges, typically several kilometres long, 20 m across, with heights on the order of 10 m. They sometimes form branching networks leading into the channels, but also occur individually and parallel to the channels. The multiple tilted terraces, the channel/valley network with many fluvial-like characteristics, and the distributed source regions, suggest that the landforms within the Rahway basin are unlikely to have formed through purely volcanic processes. Rather, the channels within the Rahway basin are consistent with a genesis requiring the flow of liquid water, and the sinuous ridges with melting of a static ice body that occupied the basin. We suggest a hypothesis of rapid basin

  12. Mineralogy and stratigraphy of phyllosilicate-bearing and dark mantling units in the greater Mawrth Vallis/west Arabia Terra area: Constraints on geological origin

    USGS Publications Warehouse

    Noe Dobrea, E.Z.; Bishop, J.L.; McKeown, N.K.; Fu, R.; Rossi, C.M.; Michalski, J.R.; Heinlein, C.; Hanus, V.; Poulet, F.; Mustard, R.J.F.; Murchie, S.; McEwen, A.S.; Swayze, G.; Bibring, J.-P.; Malaret, E.; Hash, C.

    2010-01-01

    Analyses of MRO/CRISM images of the greater Mawrth Vallis region of Mars affirm the presence of two primary phyllosilicate assemblages throughout a region ∼1000 × 1000 km. These two units consist of an Fe/Mg-phyllosilicate assemblage overlain by an Al-phyllosilicate and hydrated silica assemblage. The lower unit contains Fe/Mg-smectites, sometimes combined with one or more of these other Fe/Mg-phyllosilicates: serpentine, chlorite, biotite, and/or vermiculite. It is more than 100 m thick and finely layered at meter scales. The upper unit includes Al-smectite, kaolin group minerals, and hydrated silica. It is tens of meters thick and finely layered as well. A common phyllosilicate stratigraphy and morphology is observed throughout the greater region wherever erosional windows are present. This suggests that the geologic processes forming these units must have occurred on at least a regional scale. Sinuous ridges (interpreted to be inverted channels) and narrow channels cut into the upper clay-bearing unit suggesting that aqueous processes were prevalent after, and possibly during, the deposition of the layered units. We propose that layered units may have been deposited at Mawrth Vallis and then subsequently altered to form the hydrated units. The Fe/Mg-phyllosilicate assemblage is consistent with hydrothermal alteration or pedogenesis of mafic to ultramafic rocks. The Al-phyllosilicate/hydrated silica unit may have formed through alteration of felsic material or via leaching of basaltic material through pedogenic alteration or a mildly acidic environment. These phyllosilicate-bearing units are overlain by a darker, relatively unaltered, and indurated material that has probably experienced a complex geological history.

  13. Huo Hsing Vallis

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 5 June 2002) The Science A portion of an ancient channel called the Huo Hsing Vallis seen in the center of this image. As with all channel forms on Mars, it was carved by some moving fluid but that fluid can not automatically be assumed to be water. Lava and even wind can sculpt channel forms that mimic those of flowing water. In this case, the presence of pronounced oxbow bends in the channel favors the conclusion that water was the fluid. It is interesting that the ripple-like ridges on the channel floor mimic current ripples found in many streams on Earth. But the fluid responsible for their formation likely is the wind. Similar ripples occur in many places on Mars that have no relationship to channels. Surrounding the channel is an intensely eroded landscape known as etched terrain. The many layers that were deposited in the past are now being eroded away by the wind. In the process, unusual polygonal ridges are being exposed, the most prominent of which appear just north of the oxbow bends. The mechanism by with they form is poorly understood. It is possible that they began as polygonal troughs similar in form and origin as those that form in permafrost regions on Earth like the Canadian Arctic. If the troughs were subsequently filled in by sediment that solidified into a more resistant deposit than the surrounding material, later erosion would leave behind ridges in place of the former troughs. Known as inverted topography, there are examples of this type of landform in other etched terrains on Mars. The Story For thousands of years, many cultures the world over have studied the planets, first by observing their motions in the night sky, later through telescopes, and today through up-close observation enabled by spacecraft. Many places on Mars are given names that honor the long history of contributions by all peoples to Mars exploration. Huo Hsing, the Chinese word for the planet Mars, is the namesake of the ancient channel shown above. As with all

  14. Clay Bearing Units in the Region around Mawrth Vallis: Stratigraphy, Extent, and Possible Alteration Fronts

    NASA Technical Reports Server (NTRS)

    Dobrea, E. Z. Noe; Bishop, J. L.; McKeown, N. K.; Swayze, G.; Michalski, J. R.; Poulet, F.; Bibring, J.-P.; Mustard, J. F.; Ehlmann, B. L.; Arvidson, R.; hide

    2007-01-01

    The largest exposure of phyllosilicates on Mars occurs on the highland plains around Mawrth Vallis. This exposure extends for about 300 km southward from the edge of the dichotomy boundary, covering an area greater than 200 x 300 kilometers over an elevation range of approximately 2000 meters. At least two different types of hydrated phyllosilicates (Fe/Mg-rich and Al-rich phyllosilicates) have been identified in OMEGA data based on absorption bands near 2.3 and 2.2 micrometers, respectively. These clay-bearing units are associated with layered, indurated light-toned units with complex spatial and stratigraphic relationships, and are unconfomably overlain by a darker, indurated, more heavily cratered unit. Ongoing analysis of OMEGA (approximately 1 kilometer/pixel) and CRISM multi-spectral (MSP, 200 meters/pixel) data reveal hydrated minerals with absorptions at approximately 2.2 or 2.3 micrometers in locations up to 300 kilometers away from the borders of the previously identified extent of clay-bearing units. We seek to: 1) further constrain the mineralogy of the hydrated species identified in [5], and 2) understand spatial and stratigraphic relationships between the different hydrated minerals and the cratered plains units in which they are found. In this work we perform mineralogical and stratigraphic comparisons between units to test whether these extended units may be related, in order to establish a broad zone of alteration.

  15. A new technique for identification of minerals in hyperspectral images. Application to robust characterization of phyllosilicate deposits at Mawrth Vallis using CRISM images.

    NASA Astrophysics Data System (ADS)

    Parente, M.; Bishop, J. L.

    2008-12-01

    Mapping of Mars by MRO has revealed the presence of numerous small phyllosilicate outcrops. These are typically identified in CRISM images using "summary products" (Pelkey, 2007) that consist of band ratios, depths and spectral slopes around diagnostic wavelengths. The summary products are designed to capture spectral features related to both surface mineralogy and atmospheric gases and aerosols. Such products, as an analysis tool to characterize composition as well as a targeting tool to identify areas of mineralogical interest, have been successful in capturing the known diversity of the Martian surface, and in highlighting locations with strong spectral signatures. Here we present alternative mineral mapping technique that 1) aims to increase the robustness of mineral detections with respect to the specific CRISM artifacts, 2) takes advantage of the spatial context of each pixel and 3) develops new parameters for the discrimination of species in the phyllosilicates family. We include spatial context by evaluating spectral shapes, band depths and spectral slopes for the current pixel based on its spatial neighbors within the same geological unit. Furthermore, the parameters are based on estimates that are more robust to CRISM speckling noise that might alter the parameters and potentially the mineral interpretation. As an effort to distinguish between phyllosilicates species, we are augmenting the suite of existent parameters with a set of mineral parameters that involve the position, number and shapes of diagnostic phyllosilicate absorptions. We are comparing the effectiveness of this new approach to the summary product procedure. The study shows that homogeneous mineral maps and diagnostic spectral identifications are possible as a result of the application of such new parameters. We applied the technique to the discrimination of kaolinite in Mawrth Vallis. The experiments show several small kaolinite outcrops dispersed within the more extensive Al

  16. Usability of small impact craters on small surface areas in crater count dating: Analysing examples from the Harmakhis Vallis outflow channel, Mars

    NASA Astrophysics Data System (ADS)

    Kukkonen, S.; Kostama, V.-P.

    2018-05-01

    The availability of very high-resolution images has made it possible to extend crater size-frequency distribution studies to small, deca/hectometer-scale craters. This has enabled the dating of small and young surface units, as well as recent, short-time and small-scale geologic processes that have occurred on the units. Usually, however, the higher the spatial resolution of space images is, the smaller area is covered by the images. Thus the use of single, very high-resolution images in crater count age determination may be debatable if the images do not cover the studied region entirely. Here we compare the crater count results for the floor of the Harmakhis Vallis outflow channel obtained from the images of the ConTeXt camera (CTX) and High Resolution Imaging Science Experiment (HiRISE) aboard the Mars Reconnaissance Orbiter (MRO). The CTX images enable crater counts for entire units on the Harmakhis Vallis main valley, whereas the coverage of the higher-resolution HiRISE images is limited and thus the images can only be used to date small parts of the units. Our case study shows that the crater count data based on small impact craters and small surface areas mainly correspond with the crater count data based on larger craters and more extensive counting areas on the same unit. If differences between the results were founded, they could usually be explained by the regional geology. Usually, these differences appeared when at least one cratering model age is missing from either of the crater datasets. On the other hand, we found only a few cases in which the cratering model ages were completely different. We conclude that the crater counts using small impact craters on small counting areas provide useful information about the geological processes which have modified the surface. However, it is important to remember that all the crater counts results obtained from a specific counting area always primarily represent the results from the counting area-not the whole

  17. Northwestern Branch of Mangala Vallis

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 12 June 2002) The Science One of the many branches of the Mangala Vallis channel system is seen in this image. The water that likely carved the channels emerged from a huge graben or fracture almost 1000 km to the south. The THEMIS image shows where one of the channels exits the cratered highlands terrain onto the lowland plains. A bright scarp marks the transition between the two terrain types and demonstrates that in this location the highlands terrain is being eroded back. Note how the floor of the main channel appears to be at the same level as the lowland terrain, suggestive of a base level where erosion is no longer effective. Most of the steep slope faces in the image display darker slope streaks that are thought to be dust avalanche scars and indicate that a relatively thick mantle of dust is present in this region. Wind-sculpted ridges known as yardangs cover many of the surfaces throughout the area as shown by images from the Mars Global Surveyor mission. Most of them are at the limit of resolution in the THEMIS image but some are evident on the floor of the main channel at the point at which a smaller side channel enters. In this location they appear to extend right up to the base of the channel wall, giving the appearance that they are emerging from underneath the thick pile of material into which the channel is eroded. This suggests a geologic history in which a preexisting landscape of eroded yardangs was covered over by a thick pile of younger material that is now eroding back down to the original level. Alternatively, it is possible that the yardangs formed more recently at the abrupt transition between the channel floor and wall. More analysis is necessary to sort out the story. The Story This channel system is named 'Mangala,' the word for Mars in Sanskrit, a language of the Hindus of India that goes back more than 4,000 years, with written literature almost as long. Great epic tales have been written in this language, and Odyssey is

  18. The Advanced Research Projects Agency, 1958-1974

    DTIC Science & Technology

    1975-12-01

    Admiral John E . Clark, USN (Ret.); Mr. L. P. (1ise; ýr. William H. Godel; Brigadier General C. M. Young, Jr. USA (Ret.), and Colonel Dent Lay, LZSAF...Assigrment...... ... . . . . . iv-40 Betts’ Departure . e ..................IV-J41 V. ARPA AS A TECHNOLOGICAL ELITE . . ..... V-1 The Ruina...VI-10 Program Status 1963. . . ... . . . . . lO-10 DL= E •ER ’VI-13 Ri:hard J. Barber Associates. Inc. TABLE OF COILTTS (Cont’d) VI. (Continued

  19. Protection forest resilience after a fire event: a case study in Vallis, Switzerland

    NASA Astrophysics Data System (ADS)

    Vergani, Chiara; Werlen, Mario; Schwarz, Massimiliano

    2016-04-01

    Forests are well known to protect against natural hazards such as landslides, rockfall and floods. Nevertheless, they are dynamic ecosystems which are exposed to a variety of disturbances such as windstorms, fires, bark beetle and pathogen outbreaks. Catastrophic disturbances like windstorms and fires usually remove large portions of the canopy, starting a succession process which lead to a complete stand regeneration. Disturbances belong to the natural dynamic of forests, however they are highly undesirable in the case where forest protect infrastructure or settlements. Quantifying the decay and recovery of the protection effect of forests after disturbances is therefore important to evaluate risks and implement appropriate management techniques, when needed. This work analyzes the dynamic of a Scots Pine (Pinus silvestris) protection forests near Visp (Vallis) after a fire event, focusing on root reinforcement, which is the key factor in preventing shallow landslides. Forest cover, root distribution and root mechanical properties were analyzed 4 years after the fire event, and the root reinforcement has been quantified. Furthermore, the contribution of natural regeneration has been evaluated. Results show that the root reinforcement of Scots pine has declined massively in the forest fire area. At a distance of 1.5 m from the tree stem there is a reduction of 60% compared with the live stand. With increasing distance from the stem, the reduction in the reinforcement is even bigger. At a distance of 2.5 meters it is 12% and at 3.5 meters, only 5% of the original root reinforcement. This decrease is due to the decomposition of roots and associated change in the mechanical properties of the wood. The reinforcement of the dead roots in the forest area is estimated between 0.36 kPa and 2.64 kPa. The contribution of the emerging regeneration is estimated on average 0.01 kPa. Overall the stand provides a reinforcement between 0.37 kPa and 2.65 kPa. From the results it

  20. Estimation of the standardized ileal digestible valine to lysine ratio required for 25- to 120-kilogram pigs fed low crude protein diets supplemented with crystalline amino acids.

    PubMed

    Liu, X T; Ma, W F; Zeng, X F; Xie, C Y; Thacker, P A; Htoo, J K; Qiao, S Y

    2015-10-01

    Four 28-d experiments were conducted to determine the standardized ileal digestible (SID) valine (Val) to lysine (Lys) ratio required for 26- to 46- (Exp. 1), 49- to 70- (Exp. 2), 71- to 92- (Exp. 3), and 94- to 119-kg (Exp. 4) pigs fed low CP diets supplemented with crystalline AA. The first 3 experiments utilized 150 pigs (Duroc × Landrace × Large White), while Exp. 4 utilized 90 finishing pigs. Pigs in all 4 experiments were randomly allocated to 1 of 5 diets with 6 pens per treatment (3 pens of barrows and 3 pens of gilts) and 5 pigs per pen for the first 3 experiments and 3 pigs per pen for Exp. 4. Diets for all experiments were formulated to contain SID Val to Lys ratios of 0.55, 0.60, 0.65, 0.70, or 0.75. In Exp. 1 (26 to 46 kg), ADG increased (linear, = 0.039; quadratic, = 0.042) with an increasing dietary Val:Lys ratio. The SID Val:Lys ratio to maximize ADG was 0.62 using a linear broken-line model and 0.71 using a quadratic model. In Exp. 2 (49 to 70 kg), ADG increased (linear, = 0.021; quadratic, = 0.042) as the SID Val:Lys ratio increased. G:F improved (linear, = 0.039) and serum urea nitrogen (SUN) decreased (linear, = 0.021; quadratic, = 0.024) with an increased SID Val:Lys ratio. The SID Val:Lys ratios to maximize ADG as well as to minimize SUN levels were 0.67 and 0.65, respectively, using a linear broken-line model and 0.72 and 0.71, respectively, using a quadratic model. In Exp. 3 (71 to 92 kg), ADG increased (linear, = 0.007; quadratic, = 0.022) and SUN decreased (linear, = 0.011; quadratic, = 0.034) as the dietary SID Val:Lys ratio increased. The SID Val:Lys ratios to maximize ADG as well as to minimize SUN levels were 0.67 and 0.67, respectively, using a linear broken-line model and 0.72 and 0.74, respectively, using a quadratic model. In Exp. 4 (94 to 119 kg), ADG increased (linear, = 0.041) and G:F was improved (linear, = 0.004; quadratic, = 0.005) as the dietary SID Val:Lys ratio increased. The SID Val:Lys ratio to maximize G:F was 0

  1. Resurfacing event observed in Morpheos basin (Eridania Planitia) and the implications to the formation and timing of Waikato and Reull Valles, Mars

    NASA Astrophysics Data System (ADS)

    Kostama, V.-P.; Kukkonen, S.; Raitala, J.

    2017-06-01

    The large scale outflow channels of the Hellas impact basin are characteristic to its eastern rim region. Although the majority of the valles are located in the large-scale topographic trough connecting Hesperia Planum and Hellas basin, the most far-reaching of them, Reull Vallis is situated to the south-southeast of this trough cutting through Promethei Terra. Reull Vallis and the general geology of the region has been studied in the past, but new higher resolution image data enables us to look into the details of the features implicating the fluvial history of the region. Photogeological mapping using the available data and extensive crater counting utilizing CTX, HiRISE and HRSC provided new insights to the timing of the regional events and episodes. The study resulted in more detailed age constraints compared to the previous results from Viking images. These calculations and the geological study of the upper WMR system (Waikato Vallis - Morpheos basin - Reull Vallis) region and southern Hesperia Planum enabled us to estimate the time-frame of the (fluid) infilling of this reservoir to a model time period of 3.67-3.52 Ga which is thus also the time of the visible activity of the upper Reull Vallis and Waikato Vallis outflow channels. The results also more explicitly defined the size of previously identified Morpheos basin (confined to the 500-550 m contour lines). We also present a geological analysis of the upper parts of the WMR system, and using the observations and calculations, present an updated view of the evolution of the system and associated region.

  2. Randomized Controlled Trial of a Book-Sharing Intervention in a Deprived South African Community: Effects on Carer-Infant Interactions, and Their Relation to Infant Cognitive and Socioemotional Outcome

    ERIC Educational Resources Information Center

    Murray, Lynne; De Pascalis, Leonardo; Tomlinson, Mark; Vally, Zahir; Dadomo, Harold; MacLachlan, Brenda; Woodward, Charlotte; Cooper, Peter J.

    2016-01-01

    Background: Consistent with evidence from high-income countries (HICs), we previously showed that, in an informal peri-urban settlement in a low-middle income country, training parents in book sharing with their infants benefitted infant language and attention (Vally, Murray, Tomlinson, & Cooper, [Vally, Z., 2015]). Here, we investigated…

  3. Vallis Marineris

    NASA Image and Video Library

    2009-09-18

    This Mars Odyssey image transects Candor Chasma and Melas Chasma. Many canyon features are clearly visible in the image, including the steep cliff faces, landslides, and layered canyon floor deposits.

  4. Niger Vallis

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 24 September 2003

    Named for a great river in Africa, the martian version is a system of eroding channels that empties into the Hellas impact basin. One style of erosion is evident in this image, where the upper branches of the Niger are merging. Some process weakens the crust until it founders, producing large slump blocks that continue to erode. This process enlarges the channels and ultimately may lead to a single upper channel.

    Image information: VIS instrument. Latitude -34.7, Longitude 92.6 East (267.4 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  5. Patapsco Vallis

    NASA Image and Video Library

    2010-01-13

    This NASA 2001 Mars Odyssey spacecraft image shows two different types of linear depressions. The wide depression at the top of the frame is Elysium Fossae, which most likely formed due to tectonic activity.

  6. Kasei Vallis

    NASA Image and Video Library

    2002-12-04

    The scoured grooves in the catastrophic outflow channels shown in this image from NASA Mars Odyssey spacecraft formed hundreds of million of years ago and have the appearance of wood grain. They now host dune-like ripples of windblown material. http://photojournal.jpl.nasa.gov/catalog/PIA04015

  7. Lunar and Planetary Science XXXV: Ancient Mars Water and Landforms

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Titles in this section include: 1) Giant Lowland Polygons: Relics of an Ancient Martian Ocean? 2) Lake Shorelines: Earth Analogs for Hypothesized Martian Coastal Features; 3) Complex Evolution of Paleolacustrine Systems on Mars: An Example from the Holden Crater; 4) Geomorphology and Hydraulics of Ma'adim Vallis, Mars, During a Noachian/Hesperian Boundary Paleoflood; 5) Geologic Evolution of Dao Vallis, Mars; 6) Advances in Reconstructing the Geologic History of the Chryse Region Outflow Channels on Mars; 7) Ravi Vallis, Mars - Paleoflood Origin and Genesis of Secondary Chaos Zones; 8) Walla Walla Vallis and Wallula Crater: Two Recently Discovered Martian Features Record Aqueous History; 9) Tharsis Recharge: a Source of Groundwater for Martian Outflow Channels; 10) Factors Controlling Water Volumes and Release Rates in Martian Outflow Channels; 11) Significance of Confined Cavernous Systems for Outflow Channel Water Sources, Reactivation Mechanisms and Chaos Formation; 12) Systematic Differences in Topography of Martian and Terrestrial Drainage Basins; 13) Waves on Seas of Mars and Titan: Wind-Tunnel Experiments on Wind-Wave Generation in Extraterrestrial Atmospheres.

  8. Estimation of the standardized ileal digestible valine to lysine ratio in 13- to 32-kilogram pigs

    USDA-ARS?s Scientific Manuscript database

    Three experiments were conducted to determine the optimum standardized ileal digestible Val to Lys (SID Val:Lys) ratio for 13 to 32 kg pigs. In Exp. 1, a Val deficient basal diet containing 0.60% L-Lys•HCl, 1.21% SID Lys, and 0.68% SID Val was developed (0.56 SID Val:Lys). Performance of pigs fed th...

  9. The effect of increasing the dietary valine-to-lysine ratio on sow metabolism, milk production, and litter growth.

    PubMed

    Strathe, A V; Bruun, T S; Zerrahn, J-E; Tauson, A-H; Hansen, C F

    2016-01-01

    A study was conducted to investigate the effect of increasing the dietary valine-to-lysine ratio (Val:Lys) for lactating sows weaning more than 12 piglets. Five hundred fifty-eight sows (parity 1 to 4) were allotted to 6 dietary treatments from 2 d postpartum, when litters were standardized to 14 piglets. Diets were analyzed to have a total dietary Val:Lys of 0.84, 0.86, 0.88, 0.90, 0.95, or 0.99:1. On all 558 sows, BW, back fat thickness (BF), and litter weight were registered at d 108 of gestation and d 2 and 25 (weaning) postpartum. On a subsample of 72 sows, additional measurements were made: sow BW and BF were measured on d 17 and litter weight was measured on d 10 and 17, and blood and urine samples were collected weekly. The litter size at weaning was not affected by the dietary Val:Lys ( = 0.23) and, on average, the sows weaned 13.0 ± 1.1 piglets. Average daily gain of the litter (2.93 ± 0.53 kg/d; = 0.84), litter weight at weaning ( = 0.67), the average milk yield (11.3 ± 1.4 kg/d; = 0.49), and milk contents of fat ( = 0.57), protein ( = 0.18), and lactose ( = 0.20) were not affected by the dietary Val:Lys. Increasing the dietary Val:Lys increased the milk concentration of Val ( < 0.05) and Ile ( < 0.01). The change in sow BW and BF were similar for all sows from d 2 to 17, d 17 to 25, and d 2 to 25 ( > 0.05). During lactation, sows, on average, had a BW and back fat loss of 22.1 ± 12.7 kg and 2.9 ± 1.7 mm, respectively. Plasma concentrations of glucose ( = 0.26), lactate ( = 0.95), urea N ( = 0.84), NEFA ( = 0.24), and creatinine ( = 0.42); urine concentration of creatinine ( = 0.57); and concentrations of AA in whole blood ( > 0.05) were not affected by the dietary Val:Lys. In conclusion, there was no effect of increasing the total dietary Val:Lys above 0.84:1 on sow metabolism and litter performance during lactation.

  10. Standardized ileal digestible valine:lysine dose response effects in 25- to 45-kg pigs under commercial conditions.

    PubMed

    Gonçalves, Marcio A D; Tokach, Mike D; Dritz, Steve S; Bello, Nora M; Touchette, Kevin J; Goodband, Robert D; DeRouchey, Joel M; Woodworth, Jason C

    2018-03-06

    Two experiments were conducted to estimate the standardized ileal digestible valine:lysine (SID Val:Lys) dose response effects in 25- to 45-kg pigs under commercial conditions. In experiment 1, a total of 1,134 gilts (PIC 337 × 1050), initially 31.2 kg ± 2.0 kg body weight (BW; mean ± SD) were used in a 19-d growth trial with 27 pigs per pen and seven pens per treatment. In experiment 2, a total of 2,100 gilts (PIC 327 × 1050), initially 25.4 ± 1.9 kg BW were used in a 22-d growth trial with 25 pigs per pen and 12 pens per treatment. Treatments were blocked by initial BW in a randomized complete block design. In experiment 1, there were a total of six dietary treatments with SID Val at 59.0, 62.5, 65.9, 69.6, 73.0, and 75.5% of Lys and for experiment 2 there were a total of seven dietary treatments with SID Val at 57.0, 60.6, 63.9, 67.5, 71.1, 74.4, and 78.0% of Lys. Experimental diets were formulated to ensure that Lys was the second limiting amino acid throughout the experiments. Initially, linear mixed models were fitted to data from each experiment. Then, data from the two experiments were combined to estimate dose-responses using a broken-line linear ascending (BLL) model, broken-line quadratic ascending (BLQ) model, or quadratic polynomial (QP). Model fit was compared using Bayesian information criterion (BIC). In experiment 1, ADG increased linearly (P = 0.009) with increasing SID Val:Lys with no apparent significant impact on G:F. In experiment 2, ADG and ADFI increased in a quadratic manner (P < 0.002) with increasing SID Val:Lys whereas G:F increased linearly (P < 0.001). Overall, the best-fitting model for ADG was a QP, whereby the maximum mean ADG was estimated at a 73.0% (95% CI: [69.5, >78.0%]) SID Val:Lys. For G:F, the overall best-fitting model was a QP with maximum estimated mean G:F at 69.0% (95% CI: [64.0, >78.0]) SID Val:Lys ratio. However, 99% of the maximum mean performance for ADG and G:F were achieved at, 68% and 63% SID Val:Lys ratio

  11. Valine needs in starting and growing Cobb (500) broilers.

    PubMed

    Tavernari, F C; Lelis, G R; Vieira, R A; Rostagno, H S; Albino, L F T; Oliveira Neto, A R

    2013-01-01

    Two independent experiments were conducted with male Cobb × Cobb 500 broilers to determine the optimal valine-to-digestible-lysine ratio for broiler development. We conducted a randomized block experiment with 7 treatments, each with 8 replicates of 25 starter birds (8 to 21 d of age) and 20 finisher (30 to 43 d of age) birds. To prevent any excess of digestible lysine, 93% of the recommended level of digestible lysine was used to evaluate the valine-to-lysine ratio. The utilized levels of dietary digestible lysine were 10.7 and 9.40 g/kg for the starting and growing phases, respectively. A control diet with 100% of the recommended level of lysine and an adequate valine-to-lysine ratio was also used. The feed intake, weight gain, feed conversion ratio, and carcass parameters were evaluated. The treatments had no significant effect on the feed intakes or carcass parameters in the starter and finisher phases. However, during both of the studied phases, we observed a quadratic effect on weight gain and the feed conversion ratio. The broilers of both phases that were fed test diets with the lower valine-to-lysine (Val/Lys) ratio had poorer performance compared with those broilers fed control diets. However, when higher Val/Lys ratios were used for the starting and growing broilers that were fed test diets, the 2 groups had similar performance. During the starting phase, in broilers that were fed a higher Val/Lys ratio, weight gain, and the feed conversion ratio improved by 5.5% compared with broilers fed the basal diets. The broilers in the growing phase also had improved performance (by 7 to 8%) when the test diets had higher Val/Lys ratios. Based on the analysis of the starter phase data, we concluded that the optimal digestible Val/Lys ratio for Cobb × Cobb 500 broilers is 77%, whereas for birds in the finisher phase (30 to 43 d of age), a digestible Val/Lys ratio of 76% is suggested.

  12. Cerberus Fossae, Elysium, Mars: a source for lava and water

    NASA Astrophysics Data System (ADS)

    Plescia, J. B.

    2003-07-01

    Cerberus Fossae, a long fracture system in the southeastern part of Elysium, has acted as a conduit for the release of both lava and water onto the surface. The southeastern portion of the fracture system localized volcanic vents having varying morphology. In addition, low shields occur elsewhere on the Cerberus plains. Three locations where the release of water has occurred have been identified along the northwest (Athabasca and Grjota' Vallis) and southeast (Rahway Vallis) portions of the fossae. Water was released both catastrophically and noncatastrophically from these locations. A fluvial system that extends more than 2500 km has formed beginning at the lower flank of the Elysium rise across the Cerberus plains and out through Marte Vallis into Amazonis Planitia. The timing of the events is Late Amazonian.

  13. Constraints on the Martian cratering rate imposed by the SNC meteorites and Vallis Marineris layered deposits

    NASA Technical Reports Server (NTRS)

    Brandenburg, J. E.

    1993-01-01

    Following two independent lines of evidence -- estimates of the age and formation time of a portion of the Martian geologic column exposed in the layered deposits and the crystallization and ejection ages of the SNC meteorites -- it appears that the Martian cratering rate must be double the lunar rate or even higher. This means models such as NHII or NHIII (Neukum and Hiller models II and III), which estimate the Martian cratering rate as being several times lunar are probably far closer to reality on Mars than lunar rates. The effect of such a shift is profound: Mars is transformed from a rather Moon-like place into a planet with vigorous dynamics, multiple large impacts, erosion, floods, and volcanism throughout its history. A strong shift upward in cratering rates on Mars apparently solves some glaring problems; however, it creates others. The period of time during which Earth-like atmospheric conditions existed, the liquid water era on Mars, persists in NHIII up to only 0.5 b.y. ago. Scenarios of extended Earth-like conditions on Mars have been discounted in the past because they would have removed many of the craters from the early bombardment era found in the south. It does appear that some process of crater removal was quite vigorous in the north during Mars' past. Evidence exists that the northern plains may have been the home of long-lived seas or perhaps even a paleo-ocean, so models exist for highly localized destruction of craters in the north. However, the question of how the ancient crater population could be preserved in the south under a long liquid-water era found in any high-cratering-rate models is a serious question that must be addressed. It does appear to be a higher-order problem because it involves low-energy dynamics acting in localized areas, i.e., erosion of craters in the south of Mars, whereas the two problems with the low-cratering-rate models involve high-energy events acting over large areas: the formation of the Vallis Marineris

  14. Thermal studies of Martian channels and valleys using Termoskan data: New results

    NASA Technical Reports Server (NTRS)

    Betts, B. H.; Murray, B. C.

    1993-01-01

    The Termoskan instrument onboard the Phobos '88 spacecraft acquired the highest-spatial-resolution thermal data ever obtained for Mars. Included in the thermal images are 2 km/pixel midday observations of several major channel and valley systems, including significant portions of Shalbatana Vallis, Ravi Vallis, Al-Qahira Vallis, Ma'adim Vallis, the channel connecting Valles Marineris with Hydraotes Chaos, and channel material in Eos Chasma. Termoskan also observed small portions of the southern beginnings of Simud, Tiu, and Ares Valles and some channel material in Gangis Chasma. Simultaneous broad band visible data were obtained for all but Ma'adim Vallis. We find that most of the channels and valleys have higher inertias than their surroundings, consistent with Viking IRTM-based thermal studies of Martian channels. We see for the first time that thermal inertia boundaries closely match all flat channel floor boundaries. Combining Termoskan thermal data, relative observations from Termoskan visible channel data, Viking absolute bolometric albedos, and a thermal model of the Mars surface, we have derived lower bounds on channel thermal inertias. Lower bounds on typical channel thermal inertias range from 8.4 to 12.5 (10(exp -3) cal cm(exp -2) s(exp -1/2)K(exp -1)) (352 to 523 in SI units). Lower bounds on inertia differences with the surrounding heavily cratered plains range from 1.1 to 3.5 (46 to 147 in SI units). Atmospheric and geometric effects are not sufficient to cause the inertia enhancements. We agree with previous researchers that localized, dark, high inertia areas within channels are likely eolian in nature. However, the Temloskan data show that eolian deposits do not fill the channels, nor are they responsible for the overall thermal inertia enhancement. Thermal homogeneity and strong correlation of thermal boundaries with the channel floor boundaries lead us to favor noneolian overall explanations.

  15. Erosion of Edge of the South Polar Layered Deposits

    NASA Image and Video Library

    2017-05-23

    This image from NASA's Mars Reconnaissance Orbiter shows small ripples, about 10 meters apart, located in Her Desher Vallis. Her Desher is a small channel that shows evidence of phyllosilicates -- silicates with a sheet-like structure, such as clay minerals. Much larger images of this area show that Her Desher Vallis appears isolated, with no obvious connections to craters or larger valleys. Her Desher, the ancient Egyptian name for Mars, translates to "the Red One." https://photojournal.jpl.nasa.gov/catalog/PIA21639

  16. 3D Reconstruction of the Source and Scale of Buried Young Flood Channels on Mars

    NASA Astrophysics Data System (ADS)

    Morgan, Gareth A.; Campbell, Bruce A.; Carter, Lynn M.; Plaut, Jeffrey J.; Phillips, Roger J.

    2013-05-01

    Outflow channels on Mars are interpreted as the product of gigantic floods due to the catastrophic eruption of groundwater that may also have initiated episodes of climate change. Marte Vallis, the largest of the young martian outflow channels (<500 million years old), is embayed by lava flows that hinder detailed studies and comparisons with older channel systems. Understanding Marte Vallis is essential to our assessment of recent Mars hydrologic activity during a period otherwise considered to be cold and dry. Using data from the Shallow Radar sounder on the Mars Reconnaissance Orbiter, we present a three-dimensional (3D) reconstruction of buried channels on Mars and provide estimates of paleohydrologic parameters. Our work shows that Cerberus Fossae provided the waters that carved Marte Vallis, and it extended an additional 180 kilometers to the east before the emplacement of the younger lava flows. We identified two stages of channel incision and determined that channel depths were more than twice those of previous estimates.

  17. 3D reconstruction of the source and scale of buried young flood channels on Mars.

    PubMed

    Morgan, Gareth A; Campbell, Bruce A; Carter, Lynn M; Plaut, Jeffrey J; Phillips, Roger J

    2013-05-03

    Outflow channels on Mars are interpreted as the product of gigantic floods due to the catastrophic eruption of groundwater that may also have initiated episodes of climate change. Marte Vallis, the largest of the young martian outflow channels (<500 million years old), is embayed by lava flows that hinder detailed studies and comparisons with older channel systems. Understanding Marte Vallis is essential to our assessment of recent Mars hydrologic activity during a period otherwise considered to be cold and dry. Using data from the Shallow Radar sounder on the Mars Reconnaissance Orbiter, we present a three-dimensional (3D) reconstruction of buried channels on Mars and provide estimates of paleohydrologic parameters. Our work shows that Cerberus Fossae provided the waters that carved Marte Vallis, and it extended an additional 180 kilometers to the east before the emplacement of the younger lava flows. We identified two stages of channel incision and determined that channel depths were more than twice those of previous estimates.

  18. Sunset over Ares Vallis

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Every several days, Mars Pathfinder will image the sunrise and sunset on Mars. Future images will show a larger area -- we have a higher data rate than we expected when we planned this image, so we can get more information. Images taken at sunset, like this, and up to two hours later, will be used to investigate the distribution of dust within the Martian atmosphere. Already, we can see some dust layers in the images. By seeing how the twilight fades with time -- it lasts for over two hours -- we can determine that the dust extends high into the atmosphere.

  19. Geomorphology and Geology of the Southwestern Margaritifer Sinus and Argyre Regions of Mars. Part 3: Valley Types and Distribution

    NASA Technical Reports Server (NTRS)

    Parker, T. J.; Pieri, D. C.

    1985-01-01

    Three major valley tapes were identified in the SW Margaritefer Sinus and Argyre regions. Two are restricted to specific geologic units while the third is independent of the geology. The first type (the small valley networks) are found within the channeled and subdued plains unit in the eastern half of the map, in the grooved and channeled plains unit north of Nirgal Vallis, and in scattered instances in the cratered plateau unit north of Argyre. The even smaller valleys just inside Argyre's rim and on the inner slopes of many large craters are not directly related to the processes which formed the small valleys but are a result, instead, of post-impact modification of the crater walls. The second type of valley network is represented by Nirgal Vallis and the similar, shorter continuation of it to the west. This type is found only in the smooth plains material west of Uzboi Vallis in the map area. The third type of valley network is that of the Uzbol-Holden-Ladon valles system. This system is related to catastrophic outflow from Argyre Basin and is topographically rather than geologically controlled.

  20. Fluvial to Lacustrine Facies Transitions in Gale Crater, Mars

    NASA Technical Reports Server (NTRS)

    Sumner, Dawn Y.; Williams, Rebecca M. E.; Schieber, Juergen; Palucis, Marisa C.; Oehler, Dorothy Z.; Mangold, Nicolas; Kah, Linda C.; Gupta, Sanjeev; Grotzinger, John P.; Grant, John A., III; hide

    2015-01-01

    NASA's Curiosity rover has documented predominantly fluvial sedimentary rocks along its path from the landing site to the toe of the Peace Vallis alluvial fan (0.5 km to the east) and then along its 8 km traverse across Aeolis Palus to the base of Aeolis Mons (Mount Sharp). Lacustrine facies have been identified at the toe of the Peace Vallis fan and in the lowermost geological unit exposed on Aeolis Mons. These two depositional systems provide end members for martian fluvial/alluvial-lacustrine facies models. The Peace Vallis system consisted of an 80 square kilometers alluvial fan with decimeter-thick, laterally continuous fluvial sandstones with few sedimentary structures. The thin lacustrine unit associated with the fan is interpreted as deposited in a small lake associated with fan runoff. In contrast, fluvial facies exposed over most of Curiosity's traverse to Aeolis Mons consist of sandstones with common dune-scale cross stratification (including trough cross stratification), interbedded conglomerates, and rare paleochannels. Along the southwest portion of the traverse, sandstone facies include south-dipping meter-scale clinoforms that are interbedded with finer-grained mudstone facies, interpreted as lacustrine. Sedimentary structures in these deposits are consistent with deltaic deposits. Deltaic deposition is also suggested by the scale of fluvial to lacustrine facies transitions, which occur over greater than 100 m laterally and greater than 10 m vertically. The large scale of the transitions and the predicted thickness of lacustrine deposits based on orbital mapping require deposition in a substantial river-lake system over an extended interval of time. Thus, the lowermost, and oldest, sedimentary rocks in Gale Crater suggest the presence of substantial fluvial flow into a long-lived lake. In contrast, the Peace Vallis alluvial fan onlaps these older deposits and overlies a major unconformity. It is one of the youngest deposits in the crater, and

  1. Stunning Image of Rosetta above Mars taken by the Philae Lander Camera

    NASA Image and Video Library

    2007-02-05

    Stunning image taken by the CIVA imaging instrument on Rosetta Philae lander just 4 minutes before closest approach at a distance of some 1000 km from Mars on Feb. 25, 2007. A portion of the spacecraft and one of its solar arrays are visible in nice detail. Beneath, the Mawrth Vallis region is visible on the planet's disk. Mawrth Vallis is particularly relevant as it is one of the areas on the Martian surface where the OMEGA instrument on board ESA's Mars Express detected the presence of hydrated clay minerals -- a sign that water may have flown abundantly on that region in the very early history of Mars. Id 217487 http://photojournal.jpl.nasa.gov/catalog/PIA18154

  2. Streamlined Island

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-514, 15 October 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows a streamlined island in Marte Vallis, a large outflow channel system that crosses the 180oW meridian between the Elysium and Amazonis regions of Mars. The flow patterns on the floor of Marte Vallis might be the remains of lava flows or mud flows. Marte is the Spanish word for Mars. Most of the largest valleys on the red planet are named for 'Mars' in various languages. This island is located near 21.8oN, 175.3oW. The picture covers an area 3 km (1.9 mi) wide and is illuminated by sunlight from the lower left.

  3. Lunar and Planetary Science XXXV: Mars: Hydrology, Drainage, and Valley Systems

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The titles in this section include: 1) Analysis of Orientation Dependence of Martian Gullies; 2) A Preliminary Relationship between the Depth of Martian Gullies and the Abundance of Hydrogen on Near-Surface Mars; 3) Water Indicators in Sirenum Terra and around the Argyre Impact Basin, Mars; 4) The Distribution of Gullies and Tounge-shaped Ridges and Their Role in the Degradation of Martian Craters; 5) A Critical Evaluation of Crater Lake Systems in Memnonia Quadrangle, Mars; 6) Impact-generated Hydrothermal Activity at Gusev Crater: Implications for the Spirit Mission; 7) Characterization of the Distributary Fan in Holden NE Crater using Stereo Analysis; 8) Computational Analysis of Drainage Basins on Mars: Appraising the Drainage Density; 9) Hypsometric Analyses of Martian Basins: A Comparison to Terrestrial, Lunar, and Venusian Hypsometry; 10) Morphologic Development of Harmakhis Vallis, Mars; 11) Mangala Valles, Mars: Investigations of the source of Flood Water and Early Stages of Flooding; 12) The Formation of Aromatum Chaos and the Water Discharge Rate at Ravi Vallis; 13) Inferring Hydraulics from Geomorphology for Athabasca Valles, Mars; 14) The Origin and Evolution of Dao Vallis: Formation and Modification of Martian Channels by Structural Collapse and Glaciation; 15) Snowmelt and the Formation of Valley Networks on Martian Volcanoes; 16) Extent of Floating Ice in an Ancient Echus Chasma/Kasei Valley System, Mars.

  4. Streamlined Island

    NASA Image and Video Library

    2014-04-15

    This image from NASA 2001 Mars Odyssey spacecraft shows a streamlined island in a broad channel in Chryse Planitia. The channel is part of the outflow region of Lobo Vallis, a northern branch of Kasei Valles.

  5. Nighttime IR Channels

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    This night time IR image shows Parana Vallis. Parana Vallis is one of many channels located in the Martian highlands SE of Eos Chasma (the eastern end of Valles Marineris). Parana Vallis is likely to have been formed by fluvial activity.

    NOTE: in nighttime images North is to the bottom of the image.

    Image information: IR instrument. Latitude -24.6, Longitude 349.7 East (10.3 West). 100 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  6. Recent Geological and Hydrological Activity in Amazonis and Elysium Basins and Their Link, Marte Valles (AME): Prime Target for Future Reconnaissance

    NASA Astrophysics Data System (ADS)

    Dohm, J. M.; Robbins, S. J.; Hynek, B. M.

    2012-03-01

    Amazonis and Elysium basins and their link, Marte Vallis (AME), uniquely point to a geologically and hydrologically active Mars. We will present evidence for why AME reconnaissance can help address whether Mars is geologically, hydrologically, and biologically active.

  7. Tithonium Chasma/Ius Chasma

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Banded outcrops in walls of Tithonium Chasma/Ius Chasma section of Vallis Marineris. This 4.6 x 4.3 km image (frame 1303) is centered near 6.6 degrees south, 90.4 degrees west.

    Figure caption from Science Magazine

  8. Candor Chasma

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Complex central deposits in the floor of the Candor Chasma section of Vallis Marineris. This 3.3 x 3.1 km image (frame 8405) is centered near 6.7 degrees south, 75.4 degrees west.

    Figure caption from Science Magazine

  9. Kasei Valles - False Color

    NASA Image and Video Library

    2015-01-07

    The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows a portion of Kasei Vallis.

  10. Aram Chaos: A Long Lived Subsurface Aqueous Environment with Strong Water Resource Potential for Human Missions on Mars

    NASA Astrophysics Data System (ADS)

    Sibille, L.; Mueller, R. P.; Niles, P. B.; Glotch, T.; Archer, P. D.; Bell, M. S.

    2015-10-01

    Aram Chaos is a 280-km-wide near-circular structure near the outflow channel Ares Vallis and Aureum Chaos. It is a compelling landing site for human explorers featuring multiple science ROIs with a compelling resource ROI with polyhydrated sulfates.

  11. Visualization of Buried Marte Vallis Channels

    NASA Image and Video Library

    2013-03-07

    This illustration schematically shows where the Shallow Radar instrument on NASA Mars Reconnaissance Orbiter detected flood channels that had been buried by lava flows in the Elysium Planitia region of Mars.

  12. Ripple Trap

    NASA Image and Video Library

    2006-04-03

    This Mars Global Surveyor MGS Mars Orbiter Camera MOC image shows the margin of a lava flow on a cratered plain in the Athabasca Vallis region of Mars. Remarkably, the cratered plain in this scene is essentially free of bright, windblown ripples

  13. Teachers' Views of School-Based Professional Learning in Six High-Performing, High-Poverty, Urban Schools

    ERIC Educational Resources Information Center

    Reinhorn, Stefanie Karchmer

    2015-01-01

    Policy makers, practitioners and scholars agree that teachers need sustained job-embedded professional learning experiences to help students meet the demands of new accountability systems, higher education, and the workforce (Smylie, Miretzky, & Konkol, 2004; Valli & Buese, 2007). Research shows that job-embedded learning for teachers can…

  14. The Organized Contradictions of Professional Development and School Improvement

    ERIC Educational Resources Information Center

    Sappington, Neil; Pacha, Joseph; Baker, Paul; Gardner, Dianne

    2012-01-01

    "One of the most persistent findings from research on school improvement is, in fact, the symbiotic relationship between professional development and school improvement efforts" (Hawley & Valli, 1999, p. 129). These researchers, and others in the field, argue that there must be a direct relationship between the professional…

  15. Auqakuh Stripe

    NASA Image and Video Library

    2006-06-01

    This MOC image shows windblown ripples on the floor of Auqakuh Vallis. The light-toned area, running diagonally across the scene from the lower left to the upper right, may be dust that has accumulated in the bottom of the valley and on top of the ripples

  16. Sedimentary geomorphology of the Mars Pathfinder Landing Site

    NASA Technical Reports Server (NTRS)

    Rice, James W., Jr.; Parker, Timothy Jay

    1997-01-01

    The first landing on Mars in over 20 years will take place July 4, 1997, near te mouth of the Ares Vallis outflow channel located in southeastern Chryse Planitia. Mars Pathfinder, unlike Viking 1, is expected to land on a surface that has a distinct and unambiguous fluvial signature.

  17. Redefining Professional Development. Newsletter

    ERIC Educational Resources Information Center

    Center for Comprehensive School Reform and Improvement, 2006

    2006-01-01

    The research on effective professional development is consistent across many studies. Researchers Willis Hawley and Linda Valli (Westchester Institute for Human Services Research, n.d.), in their synthesis of the professional development literature, find that high-quality teacher development is as follows: (1) Informed by research on teaching and…

  18. Mineral abundances at the final four curiosity study sites and implications for their formation

    NASA Astrophysics Data System (ADS)

    Poulet, F.; Carter, J.; Bishop, J. L.; Loizeau, D.; Murchie, S. M.

    2014-03-01

    A component of the landing site selection process for the Mars Science Laboratory (MSL) involved the presence of phyllosilicates as the main astrobiological targets. Gale crater was selected as the MSL landing site from among 4 down selected study sites (Gale, Eberswalde and Holden craters, Mawrth Vallis) that addressed the primary scientific goal of assessing the past habitability of Mars. A key constraint on the formation process of these phyllosilicate-bearing deposits is in the precise mineralogical composition. We present a reassessment of the mineralogy of the sites combined with a determination of the modal mineralogy of the major phyllosilicate-bearing deposits of the four final study sites from the modeling of near-infrared spectra using a radiative transfer model. The largest abundance of phyllosilicates (30-70%) is found in Mawrth Vallis, the lowest one in Eberswalde (<25%). Except for Mawrth Vallis, the anhydrous phases (plagioclase, pyroxenes and martian dust) are the dominant phases, suggesting formation conditions with a lower alteration grade and/or a post-formation mixing with anhydrous phases. The composition of Holden layered deposits (mixture of saponite and micas with a total abundance in the range of 25-45%) suggests transport and deposition of altered basalts of the Noachian crust without major chemical transformation. For Eberswalde, the modal mineralogy is also consistent with detrital clays, but the presence of opaline silica indicates that an authigenic formation occurred during the deposition. The overall composition including approximately 20-30% smectite detected by MSL in the rocks of Yellow-knife Bay area interpreted to be material deposited on the floor of Gale crater by channels (http://www.nasa.gov/mission_pages/msl/news/msl20130312.html).

  19. High-Resolution Radar Imagery of Mars

    NASA Astrophysics Data System (ADS)

    Harmon, John K.; Nolan, M. C.

    2009-09-01

    We present high-resolution radar images of Mars obtained during the 2005 and 2007 oppositions. The images were constructed from long-code delay-Doppler observations made with the Arecibo S-band (13-cm) radar. The average image resolution of 3 km represented a better than order-of-magnitude improvement over pre-upgrade Arecibo imagery of the planet. Images of depolarized reflectivity (an indicator primarily of wavelength-scale surface roughness) show the same bright volcanic flow features seen in earlier imagery, but with much finer detail. A new image of the Elysium region shows fine detail in the radar-bright channels of Athabasca Vallis, Marte Vallis, and Grjota Vallis. The new images of Tharsis and Olympus Mons also show a complex array of radar-bright and radar-dark features. Southern Amazonis exhibits some of the most complex and puzzling radar-bright structure on the planet. Another curiosity is the Chryse/Xanthe/Channels region, where we find some radar-bright features in or adjacent to fluvial chaos structures. Chryse/Xanthe is also the only region of Mars showing radar-bright craters (which are rare on Mars but common on the Moon and Mercury). We also obtained the first delay-Doppler image showing the enhanced backscatter from the residual south polar ice cap. In addition to the depolarized imagery, we were able to make the first delay-Doppler images of the circular polarization ratio (an important diagnostic for surface roughness texture). We find that vast areas of the radar-bright volcanic regions have polarization ratios close to unity. Such high ratios are rare for terrestrial lava flows and only seen for extremely blocky surfaces giving high levels of multiple scattering.

  20. Columbia Hills, Mars: aeolian features seen from the ground and orbit

    USGS Publications Warehouse

    Greeley, Ronald; Whelley, Patrick L.; Neakrase, Lynn D.V.; Arvidson, Raymond E.; Bridges, Nathan T.; Cabrol, Nathalie A.; Christensen, Philip R.; Di, Kaichang; Foley, Daniel J.; Golombek, Matthew P.; Herkenhoff, Kenneth; Knudson, Amy; Kuzmin, Ruslan O.; Li, Ron; Michaels, Timothy; Squyres, Steven W.; Sullivan, Robert; Thompson, Shane D.

    2008-01-01

    Abundant wind-related features occur along Spirit's traverse into the Columbia Hills over the basaltic plains of Gusev Crater. Most of the windblown sands are probably derived from weathering of rocks within the crater, and possibly from deposits associated with Ma'adim Vallis. Windblown particles act as agents of abrasion, forming ventifacts, and are organized in places into various bed forms. Wind-related features seen from orbit, results from atmospheric models, and considerations of topography suggest that the general wind patterns and transport pathways involve: (1) winter nighttime winds that carry sediments from the mouth of Ma'adim Vallis into the landing site area of Spirit, where they are mixed with locally derived sediments, and (2) winter daytime winds that transport the sediments from the landing site southeast toward Husband Hill; similar patterns occur in the summer but with weaker winds. Reversals of daytime flow out of Gusev Crater and nighttime wind flow into the crater can account for the symmetry of the bed forms and bimodal orientations of some ventifacts.

  1. Columbia Hills, Mars: Aeolian features seen from the ground and orbit

    USGS Publications Warehouse

    Greeley, R.; Whelley, P.L.; Neakrase, L.D.V.; Arvidson, R. E.; Bridges, N.T.; Cabrol, N.A.; Christensen, P.R.; Di, K.; Foley, D.J.; Golombek, M.P.; Herkenhoff, K.; Knudson, A.; Kuzmin, R.O.; Li, R.; Michaels, T.; Squyres, S. W.; Sullivan, R.; Thompson, S.D.

    2008-01-01

    Abundant wind-related features occur along Spirit's traverse into the Columbia Hills over the basaltic plains of Gusev Crater. Most of the windblown sands are probably derived from weathering of rocks within the crater, and possibly from deposits associated with Ma'adim Vallis. Windblown particles act as agents of abrasion, forming ventifacts, and are organized in places, into various bed forms. Wind-related features seen from orbit, results from atmospheric models, and considerations of topography suggest that the general wind patterns and transport pathways involve: (1) winter nighttime winds that carry sediments from the mouth of Ma'adim. Vallis into the landing site area of Spirit, where they are mixed with locally derived sediments, and (2) winter daytime winds that transport the sediments from the landing site southeast toward Husband Hill; similar patterns occur in the summer but with weaker winds. Reversals of daytime flow out of Gusev Crater and nighttime wind flow into the crater can account for the symmetry of the bed forms and bimodal orientations of some ventifacts. Copyright 2008 by the American Geophysical Union.

  2. Mars 2020 Candidate Landing Site in McLaughlin Crater

    NASA Image and Video Library

    2016-01-14

    McLaughlin Crater (21.9 N, 337.6 E) is a large, approximately 95-kilometer diameter impact crater located north of Mawrth Vallis, in Arabia Terra, a region that was made famous by the book and movie "The Martian" by Andy Weir. McLaughlin Crater straddles three major terrain types: the Northern lowlands, the Southern highlands and the Mawrth Vallis region. The crater floor is thought to be covered by clays and carbonates that were deposited in a deep lake at least 3.8 billion years ago perhaps by ground water upwelling from beneath the crater floor (Michalski et al., 2013, Nature Geoscience). McLaughlin Crater is listed as a candidate landing site for the 2020 Mars surface mission. Although it is described as a "flat, low-risk and low-elevation landing zone," the region in this image on the southern floor of the crater shows a complex surface of eroded layers that are rough in places. An unusual feature is a straight fracture cutting diagonally across the layered material at the bottom portion of the image that may be a fault line. http://photojournal.jpl.nasa.gov/catalog/PIA20338

  3. Mars Pathfinder

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    First of NASA's Discovery missions. Launched in December 1996 and arrived at Mars on 4 July 1997. Mainly intended as a technology demonstration mission. Used airbags to cushion the landing on Mars. The Carl Sagan Memorial station returned images of an ancient flood plain in Ares Vallis. The 10 kg Sojourner rover used an x-ray spectrometer to study the composition of rocks and travelled about 100 ...

  4. Investigating the volcanic versus aqueous origin of the surficial deposits in Eastern Elysium Planitia, Mars

    NASA Astrophysics Data System (ADS)

    Voigt, Joana R. C.; Hamilton, Christopher W.

    2018-07-01

    The Elysium Volcanic Province consists of numerous overlapping flow units and may include the youngest lava flows on Mars. However, it is possible that these volcanic units have been modified or overprinted by aqueous processes. Understanding the timing of the igneous and aqueous events in this region is therefore essential for constraining the geological and environmental history of Mars during the Amazonian Period. We investigate the geologic evolution of Eastern Elysium Planitia to determine the relationship between major units, with the support of a geological map and chronological constraints from crater size-frequency distributions. We also evaluate the hypothesized origin of these units via volcanic, fluvial, and/or fluvioglacial processes using a detailed facies-mapping approach. The study area includes the Eastern Cerberus Fossae, Rahway Valles, and Marte Vallis. The surficial deposits in Rahway Valles were formerly interpreted to be modified by fluvial and fluvioglacial processes. However, our facies map reveals that the surface of Eastern Elysium Planitia includes nineteen morphologically distinct regions (i.e., facies), which are interpreted to be the products of flood lava volcanism, including: ´a´ā, pāhoehoe, and transitional lava flow types. In contrast to previous studies, which determined that Rahway Valles and Marte Vallis consist of two distinct geologic units with Middle to Late Amazonian ages, the results of this work show that the region was resurfaced by at least two volcanic flows with much younger ages of 20.0 Ma and 8.8 Ma. Furthermore, by coupling results of our geologic and facies mapping with chronological constraints as well as subsurface information provided by Shallow Radar reflectors, we show that there is an erosional unconformity located between the two youngest lava flow units in Marte Vallis. We interpret that this unconformity was generated by a catastrophic aqueous flooding event that occurred only 8.8 - 20.0 Ma ago. This

  5. Evidence of ancient alteration and subaqueous activity in Oxia Planum, the candidate landing site for Exomars 2020

    NASA Astrophysics Data System (ADS)

    Quantin-Nataf, Cathy; Carter, John; Thollot, Patrick; Loizeau, Damien; Davis, Joel; Grindrod, Peter; lozach, Loic

    2017-04-01

    The ExoMars 2018 mission (ESA) has for scientific objectives to search for signs of past and present life on Mars, to investigate the water/geochemical environment as a function of depth in the shallow subsurface, to study to Martian atmospheric trace gases and to characterize the surface environment. The landing site has to be relevant with regard to these objectives while fitting the restrictive engineering constrains. From the scientific point of view, the site must be ancient, from the Early Mars period, for which many scientific evidences favor the existence of a water-related cycle. In this paper, we present the unique location called Oxia Planum, a wide clay bearing plain located between 16° and 19° North and -23° to -28° East proposed as landing site for Exomars 2020 mission. Oxia Planum is located between Ares Vallis and Marwth Vallis in a wide basin just at the outlet of Cogoon Vallis System, with elevations ranging from -2800 m down to -3100 m. The regional compositional mapping of Oxia planum has been achieved based on OMEGA data at 2.5 km/pix well as CRISM multispectral data at 200 m/pix. Mg/Fe phyllosilicates, identified and mapped based on their diagnostic absorptions at 1.4, 1.9 and 2.3 µm are exposed over about 80% of the ellipse surface. The entire unit with phyllosilicates signatures corresponds to a light-toned layered unit that is observed over a large range of elevations (from -2600 m to -3100m) suggesting that like in Marwth Vallis region, the layered and altered formation overlaps a pre-existing topography . The age returned from crater count on the clay rich formation is 3.9 Ga. At the top or embedded within the layered formation, several fluvial morphologies such as former valleys or inverted channels are observed. Also, at the top of the layered clay-rich formation, a deltaic deposit is observed suggesting sub-aqueous episodes postdating the altered layered formation. In terms of mineralogy, the putative delta fan shows layers

  6. Dust Devil Art

    NASA Technical Reports Server (NTRS)

    2005-01-01

    12 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark squiggles and streaks created by passing spring and summer dust devils near Pallacopas Vallis in the martian southern hemisphere.

    Location near: 53.9oS, 17.2oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

  7. VP35 Knockdown Inhibits Ebola Virus Amplification and Protects Against Lethal Infection in Mice

    DTIC Science & Technology

    2006-03-01

    Army Medical Research Institute of Infectious Diseases, Frederick, Maryland 21702-50112; and AVI BioPharma Inc., Corvallis, Oregon3 Received 29 June...target nucleotides within the EBOV genome or antigenome (Table 1). All PMO were synthesized and purified by AVI BioPharma Inc. (Cor- vallis, OR), as...technical assistance. We are also grateful to the Chemistry Department at AVI BioPharma Inc. for expert synthesis, purification, and analysis of all PMO

  8. Mesoscale modeling of the water vapor cycle at Mawrth Vallis: a Mars2020 and ExoMars exploration rovers high-priority landing site

    NASA Astrophysics Data System (ADS)

    Pla-García, Jorge

    2017-04-01

    Introduction: The Mars Regional Atmospheric Modeling System (MRAMS) was used to predict meteorological conditions that are likely to be encountered by the Mars 2020 (NASA) Rover at several of their respective proposed landing sites during entry, descent, and landing at Ls5 [1] and by the ExoMars (ESA) Rover at one of the final landing sites. MRAMS is ideally suited for this type of investigation; the model is explicitly designed to simu-late Mars' atmospheric circulations at the mesoscale and smaller with realistic, high-resolution surface proper-ties [2, 3]. One of the sights studied for both rovers was Mawrth Vallis (MV), an ancient water outflow channel with light colored clay-rich rocks in the mid-latitude north hemisphere (Oxia Palus quadrangle). MV is the northernmost of the Mars2020 and ExoMars landing sites and the closest to the northern polar cap water source. The primary source of water vapor to the atmosphere is the northern polar cap during the northern summer. In order to highlight MV habitability implications, additional numerical experiments at Ls90, 140 and 180, highest column abundance of water vapor is found over MV [4], were performed to study how the atmospheric circulation connects MV with the polar water source. Once the winter CO2 retreats, the underlying polar water ice is exposed and begins to sublimate. The water is transported equatorward where it is manifested in the tropical aphelion cloud belt. If transport is assumed to be the result of the summer Hadley Cell, then the polar water is carried aloft in the northern high latitude rising branch before moving equatorward and eventually toward the southern high latitudes. Thus, the mean meridional summer circulation precludes a direct water vapor connection between MV and the polar source. Around the equinoxes (Ls0 and Ls180), there is a brief transition period where the rising branch quickly crosses from one hemisphere into the other as it migrates to its more typical solstitial location

  9. Ripple Belt

    NASA Technical Reports Server (NTRS)

    2006-01-01

    16 July 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows windblown materials that have collected and been shaped into large ripples in a valley in the Auqakuh Vallis system in northeastern Arabia Terra, Mars.

    Location near: 29.1oN, 299.6oW Image width: 2 km (1.2 mi) Illumination from: lower left Season: Northern Winter

  10. Holuhraun 2014-2015 Eruption Site on Iceland: A Flood Lava Analogue for Mars

    NASA Astrophysics Data System (ADS)

    Voigt, J.; Hamilton, C. W.; Scheidt, S. P.; Bonnefoy, L. E.; Jónsdóttir, I.; Höskuldsson, A.; Thordarson, T.

    2017-09-01

    The Holuhraun eruption 2014-2015 is the largest flood lava flow in Iceland since the Laki eruption in 1783-1784. We here present the first facies map of the whole Holuhraun lava flow, which we linked to the chronological emplacement history. Furthermore the facies we identify at Holuhraun are common on the Martian surface, especially at Marte Vallis and Rahway Valles. It therefore provides unique insights into the emplacement of flood lavas on Earth and other planetary bodies.

  11. Geotourism, as a new approuch to expeloit geomorphical and geological attractions of mountain

    NASA Astrophysics Data System (ADS)

    Mehri, M.; Arezoo, S.

    2009-04-01

    Tourism is an industorial with cultural and social relationship beside minimal Enviromental contamination with income and economic scale that now is very important. Natural attractive places of each country have a famous role in absorbing & attracting the tourism. Iran is one of country with natural attractive & specific places that with historical civil that can use to attract the torism. Ecotouris is tourist that without damaging enviroment travels in nature. Some of tourist travel to see the science appearance and have scientific view. In adjacent of Hamdan and in SW of it there are place that in addiation to historical and cultural attractive has natural unique attractive so can absorb each Ecotourist. In Geologic & Geographic view this area is specific that can attract each Ecotourist that like natural science.This zone is reflecting of adjacent between,urban,rorul,tribial life & Metamophism,Magmatism , partial Melting , faulting and folding of layers. The new and famous researches carry out in thise area have suitable data with adjacent to Hamadan,Alvand Elevation,suitable way for claiming , security, Abundant water,agricultur greenvisage in this area that have cause to this place be a important &attractive place for Ecotourist & place for build a station,specially for Geotourism goals. valleys (case study Simin vally , south a Hamedan) Key words : Ecotourism , Geotourism , Simin Vally , igneous and Metamorphic Rocks , Migmati

  12. Geologic Mapping of Holden Crater and the Uzboi-Ladon-Morava Outflow System

    NASA Technical Reports Server (NTRS)

    Grant, J. A.; Irwin, R. P., III; Wilson, S. A.

    2009-01-01

    Geologic mapping in Margaritifer Terra (Fig. 1) yields important new information regarding the inventory, sources, and sinks of water during the Noachian and early Hesperian on Mars [1-7]. Drainage in southwest Margaritifer Terra is dominated by the segmented Uzboi-Ladon-Morava (ULM) meso-scale outflow system that traverses northward along the southwestern flank of the Chryse trough [4-9]. Mapping of lower Uzboi Vallis through Ladon basin highlights the extent and complexity of sedimentary deposits associated with the ULM system [5-13].

  13. No Mystery! Water Carved the Outflow Channels on Mars

    NASA Astrophysics Data System (ADS)

    Coleman, N.

    2002-12-01

    The enormous outflow channels of Chryse Planitia provide the best evidence that large amounts of water were once released onto the martian surface. The role of water has recently been challenged by the White Mars hypothesis, which claims that the channels were cut by CO2 gas-supported debris flows that also resurfaced the northern plains. Hoffman [Icarus, 2000] refers to a volumetric "misfit" between outburst channels and the chaos source zones. He explains that chaos collapse "...involves regolith alone which generates its own fluids from liquid CO2 and CO2-bearing ices within its own volume." Hoffman [LPSC 32, #1257] argues that release of liquid CO2 produced Aromatum Chaos, and a hypothetical energetic "jet" of gas and debris carved Ravi Vallis. He notes that water would have had to be locally recharged in many episodes to provide enough discharge to form the chaos and channel. However, these assertions appear incorrect because the fluid source was a distant surface impoundment, not local recharge. Carr [Water on Mars, 1996] describes a 400-km-long zone of subsidence that extends northward from Ganges Chasma to the source of Shalbatana Vallis. MOLA data reveal that this subsidence also extends eastward to Aromatum Chaos, the source of Ravi Vallis. The field relations show that a liquid-filled impoundment in Ganges Chasma drained northward via subterranean flowpaths to maintain surface flows in Shalbatana and Ravi Valles. The fact that the flows began at a surface impoundment virtually eliminates liquid CO2 as the flowing agent. Liquid CO2 would not be stable at the surface unless the atmospheric pressure exceeded 5 atm. A recent study by Stewart and Nimmo [JGR, in press] suggests that CO2 in liquid, solid, or clathrate form could not be preserved within the crust over geologic time. Liquid water is much closer to its stability field even on present-day Mars. Large outflow channels, such as Kasei and Tiu-Simud Valles, likely formed through the release of

  14. Styles of Phreatomagmatic Activity Adjacent to Volcanic Constructs on Mars

    NASA Astrophysics Data System (ADS)

    Wilson, L.; Mouginis-Mark, P.

    2001-05-01

    Early in the analysis of Viking Orbiter data, it was recognized that there were numerous sites on Mars where igneous intrusions may have interacted with ice near the surface. Hrad Vallis (34N, 142E) in Western Elysium Planitia, and Olympica Fossae (25N, 245E) to the southwest of Ceraunius Fossae, were two such candidate areas. New images from the Mars Orbiter Camera show striking differences between these two sites, revealing a wide diversity of depositional and erosional features. We are therefore exploring several potential terrestrial analogs to better constrain models of heat transfer from the igneous intrusion, the style of "eruption" of the water/sediment mixtures, and the hydrologic conditions in the substrate at the time of emplacement. We have found layering at the source of Hrad Vallis, and several nearby impact craters 270 - 530 m diameter that are almost totally mantled, consistent with the deposition of 20 - 30 m of sediment around the source graben. Prominent sub-radial ridges occur within this 8,400 km2 deposit; close to the source, these ridges have a spacing of 100 - 120 m but grade to smaller ridges 60 m apart within 2 km of the source. No "de-watering" features are visible on this unit. In contrast, Olympica Fossae displays no depositional features near the source graben. We interpret these morphologic differences to be due to a higher sediment load of the fluid that reached the surface at Hrad Vallis compared with Olympica Fossae. At neither site are there signs of "weeping" graben walls, indicating that the source of the water was probably at a depth greater than that of the graben (about 60 - 100 m). With due allowance for bulking and for errors of measurement, the volumes of the deposits are comparable to the volumes of their parent source depressions. We envisage that these deposits were created by phreatomagmatic explosions in which heat from a sill-like intrusion melts ice occupying pore space in crustal rocks and boils the resulting water

  15. 2011 Black History Month

    NASA Image and Video Library

    2011-02-16

    Victoria Webb (center) discusses African-American history during a Black History Month program for John C. Stennis Space Center employees on Feb. 16. Webb, a 103-year-old native of Pass Christian, was guest speaker for the program, sponsored by the Stennis Diversity Council and the Naval Meteorology and Oceanography Command. She was joined in her presentation by Valli Battle (left), a NAVOCEANO employee at Stennis, and friend Jeanell Barnes. Black History Month was first observed in 1976 and is celebrated each February. The 2011 theme was African-Americans and the Civil War.

  16. Multispectral Imaging from Mars PATHFINDER

    NASA Technical Reports Server (NTRS)

    Ferrand, William H.; Bell, James F., III; Johnson, Jeffrey R.; Bishop, Janice L.; Morris, Richard V.

    2007-01-01

    The Imager for Mars Pathfinder (IMP) was a mast-mounted instrument on the Mars Pathfinder lander which landed on Mars Ares Vallis floodplain on July 4, 1997. During the 83 sols of Mars Pathfinders landed operations, the IMP collected over 16,600 images. Multispectral images were collected using twelve narrowband filters at wavelengths between 400 and 1000 nm in the visible and near infrared (VNIR) range. The IMP provided VNIR spectra of the materials surrounding the lander including rocks, bright soils, dark soils, and atmospheric observations. During the primary mission, only a single primary rock spectral class, Gray Rock, was recognized; since then, Black Rock, has been identified. The Black Rock spectra have a stronger absorption at longer wavelengths than do Gray Rock spectra. A number of coated rocks have also been described, the Red and Maroon Rock classes, and perhaps indurated soils in the form of the Pink Rock class. A number of different soil types were also recognized with the primary ones being Bright Red Drift, Dark Soil, Brown Soil, and Disturbed Soil. Examination of spectral parameter plots indicated two trends which were interpreted as representing alteration products formed in at least two different environmental epochs of the Ares Vallis area. Subsequent analysis of the data and comparison with terrestrial analogs have supported the interpretation that the rock coatings provide evidence of earlier martian environments. However, the presence of relatively uncoated examples of the Gray and Black rock classes indicate that relatively unweathered materials can persist on the martian surface.

  17. View of Florence, Italy area from Skylab

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A near vertical view of the Florence, Italy area as photographed from Earth orbit by one of the Itek-furnished S190-A Multispectral Photographic Facility Experiment aboard the Skylab space station. The view extends from the Ligurian Sea, an extension of the Mediterranian Sea, across the Apennine Mountians to the Po River Vally. Florence (Firenze) is near the center of the land mass. The mouth of the Arno River is at the center of the coastline. The city of Leghorn (Livorno) is on the coast just south of the Arno River. This picture was taken with type 2443 infrared color film.

  18. Geology of -30247, -35247, and -40247 Quadrangles, Southern Hesperia Planum, Mars

    NASA Technical Reports Server (NTRS)

    Mest, S. C.; Crown, D. A.

    2010-01-01

    Geologic mapping of MTM -30247, -35247, and -40247 quadrangles is being used to characterize Reull Vallis (RV) and examine the roles and timing of volatile-driven erosional and depositional processes. This study complements earlier investigations of the eastern Hellas region, including regional analyses [1-6], mapping studies of circum-Hellas canyons [7-10], and volcanic studies of Hadriaca and Tyrrhena Paterae [11-13]. Key scientific objectives include 1) characterizing RV in its "fluvial zone," and evaluating its history of formation, 2) analyzing channels in the surrounding plains and potential connections to RV, and 3) examining young, possibly sedimentary plains along RV.

  19. SHARAD Investigation of the Interaction Between Volcanism and Deep Water Release in Elysium Planitia, Mars

    NASA Astrophysics Data System (ADS)

    Morgan, G. A.; Campbell, B. A.; Carter, L. M.; Plaut, J. J.

    2011-12-01

    Situated between the equator and 12°N and extending from 130° to 180°E, Elysium Planitia is considered to be the youngest volcanic plain on Mars. Recent crater counts on individual lava units argue for multiple phases of activity over the last 230 Myrs, with the most recent volcanic features dating to just ~2 Ma. The region also contains the youngest outflow channels on the planet. Multiple channel systems which are present across the region are interpreted to have been carved by the release of deep ground water (>1 km) from the broadly east-west trending Cerberus Fossae graben system. Elysium Planitia is therefore a region of high scientific interest, as it represents an ideal site to investigate the interaction of lava and water both below and on the surface of Mars. Extensive geologic mapping of Elysium Planitia has provided detailed information concerning the stratigraphy of the major volcanic units in addition to the classification of other landforms attributed to volcanic (e.g. small shields), fluvial (e.g. outflow channels) and aeolian (e.g. yardangs) activity. Orbital sounding radar provides a means to take this work to the next level through the mapping of buried surfaces associated with a contrast in dielectric permittivity and thus can be used to investigate the 3-D structure of the subsurface. Previous studies using the SHARAD radar sounder onboard the Mars Reconnaissance Orbiter have identified multiple subsurface reflectors below the plains of Elysium Planitia. We will present our investigation of SHARAD data covering the eastern portion of this region of Mars - an area that includes the upstream reaches of Marte Vallis and the eastern extent of Cerberus Fossae. Our subsurface mapping shows remarkable correlations with published geologic maps produced using visible orbital datasets. These similarities allow us to use SHARAD data to make estimates of the average permittivity values and imply density measurements of the volcanic units. We will

  20. Remote Sensing Soil Salinity Map for the San Joaquin Vally, California

    NASA Astrophysics Data System (ADS)

    Scudiero, E.; Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.

    2015-12-01

    Soil salinization is a major natural hazard to worldwide agriculture. We present a remote imagery approach that maps salinity within a range (i.e., salinities less than 20 dS m-1, when measured as the electrical conductivity of the soil saturation extract), accuracy, and resolution most relevant to agriculture. A case study is presented for the western San Joaquin Valley (WSJV), California, USA (~870,000 ha of farmland) using multi-year Landsat 7 ETM+ canopy reflectance and the Canopy Response Salinity Index (CRSI). Highly detailed salinity maps for 22 fields (542 ha) established from apparent soil electrical conductivity directed sampling were used as ground-truth (sampled in 2013), totaling over 5000 pixels (30×30 m) with salinity values in the range of 0 to 35.2 dS m-1. Multi-year maximum values of CRSI were used to model soil salinity. In addition, soil type, elevation, meteorological data, and crop type were evaluated as covariates. The fitted model (R2=0.73) was validated: i) with a spatial k-folds (i.e., leave-one-field-out) cross-validation (R2=0.61), ii) versus salinity data from three independent fields (sampled in 2013 and 2014), and iii) by determining the accuracy of the qualitative classification of white crusted land as extremely-saline soils. The effect of land use change is evaluated over 2396 ha in the Broadview Water District from a comparison of salinity mapped in 1991 with salinity predicted in 2013 from the fitted model. From 1991 to 2013 salinity increased significantly over the selected study site, bringing attention to potential negative effects on soil quality of shifting from irrigated agriculture to fallow-land. This is cause for concern since over the 3 years of California's drought (2010-2013) the fallow land in the WSJV increased from 12.7% to 21.6%, due to drastic reduction in water allocations to farmers.

  1. Surface properties of the Mars Science Laboratory candidate landing sites: characterization from orbit and predictions

    USGS Publications Warehouse

    Fergason, R.L.; Christensen, P.R.; Golombek, M.P.; Parker, T.J.

    2012-01-01

    This work describes the interpretation of THEMIS-derived thermal inertia data at the Eberswalde, Gale, Holden, and Mawrth Vallis Mars Science Laboratory (MSL) candidate landing sites and determines how thermophysical variations correspond to morphology and, when apparent, mineralogical diversity. At Eberswalde, the proportion of likely unconsolidated material relative to exposed bedrock or highly indurated surfaces controls the thermal inertia of a given region. At Gale, the majority of the landing site region has a moderate thermal inertia (250 to 410 J m-2 K-1 s-1/2), which is likely an indurated surface mixed with unconsolidated materials. The primary difference between higher and moderate thermal inertia surfaces may be due to the amount of mantling material present. Within the mound of stratified material in Gale, layers are distinguished in the thermal inertia data; the MSL rover could be traversing through materials that are both thermophysically and compositionally diverse. The majority of the Holden ellipse has a thermal inertia of 340 to 475 J m-2 K-1 s-1/2 and consists of bed forms with some consolidated material intermixed. Mawrth Vallis has a mean thermal inertia of 310 J m-2 K-1 s-1/2 and a wide variety of materials is present contributing to the moderate thermal inertia surfaces, including a mixture of bedrock, indurated surfaces, bed forms, and unconsolidated fines. Phyllosilicates have been identified at all four candidate landing sites, and these clay-bearing units typically have a similar thermal inertia value (400 to 500 J m-2 K-1 s-1/2), suggesting physical properties that are also similar.

  2. Subpolar Atlantic cooling and North American east coast warming linked to AMOC slowdown

    NASA Astrophysics Data System (ADS)

    Rahmstorf, Stefan; Caesar, Levke; Feulner, Georg; Saba, Vincent

    2017-04-01

    Reconstructing the history of the Atlantic Meridional Overturning Circulation (AMOC) is difficult due to the limited availability of data. One approach has been to use instrumental and proxy data for sea surface temperature (SST), taking multi-decadal and longer SST variations in the subpolar gyre region as indicator for AMOC changes [Rahmstorf et al., 2015]. Recent high-resolution global climate model results [Saba et al., 2016] as well as dynamical theory and conceptual modelling [Zhang and Vallis, 2007] suggest that an AMOC weakening will not only cool the subpolar Atlantic but simultaneously warm the Northwest Atlantic between Cape Hatteras and Nova Scotia, thus providing a characteristic SST pattern associated with AMOC variations. We analyse sea surface temperature (SST) observations from this region together with high-resolution climate model simulations to better understand the linkages of SST variations to AMOC variability and to provide further evidence for an ongoing AMOC slowdown. References Rahmstorf, S., J. E. Box, G. Feulner, M. E. Mann, A. Robinson, S. Rutherford, and E. J. Schaffernicht (2015), Exceptional twentieth-century slowdown in Atlantic Ocean overturning circulation, Nature Climate Change, 5(5), 475-480, doi: 10.1038/nclimate2554. Saba, V. S., et al. (2016), Enhanced warming of the Northwest Atlantic Ocean under climate change, Journal of Geophysical Research-Oceans, 121(1), 118-132, doi: 10.1002/2015JC011346. Zhang, R., and G. K. Vallis (2007), The Role of Bottom Vortex Stretching on the Path of the North Atlantic Western Boundary Current and on the Northern Recirculation Gyre, Journal of Physical Oceanography, 37(8), 2053-2080, doi: 10.1175/jpo3102.1.

  3. The discovery of columnar jointing on Mars

    USGS Publications Warehouse

    Milazzo, M.P.; Keszthelyi, L.P.; Jaeger, W.L.; Rosiek, M.; Mattson, S.; Verba, C.; Beyer, R.A.; Geissler, P.E.; McEwen, A.S.; ,

    2009-01-01

    We report on the discovery of columnar jointing in Marte Valles, Mars. These columnar lavas were discovered in the wall of a pristine, 16-km-diameter impact crater and exhibit the features of terrestrial columnar basalts. There are discontinuous outcrops along the entire crater wall, suggesting that the columnar rocks covered a surface area of at least 200 km2, assuming that the rocks obliterated by the impact event were similarly jointed. We also see columns in the walls of other fresh craters in the nearby volcanic plains of Elysium Planitia–Amazonis Planitia, which include Marte Vallis, and in a well-preserved crater in northeast Hellas.

  4. A Global Theory of Internal Solitary Waves in Two-Fluid Systems.

    DTIC Science & Technology

    1985-09-01

    Large Amplitude Since the branch of solutions S from Theorem 2.1 is unbounded in R x (H (T) fl C O , 1 (T)) and the range of I is bounded, the norms...all k i’. L (T) and (b) ’k + A and IwkI , + as k. H (T) 0 Then wk converges to w(XlX 2 ) in C(S) fl C (B r) T*) for each bounded set B. The function w...Beale, J. T., The existence of solitary water waves, Comm. Pure Appi. Math. 30 (1977), 373-389. 7. Beir-ao da Veiga , H., Serapioni, R., and Valli, A

  5. Diversity in Mawrth Region, Mars

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This view shows diverse materials and morphologies in the region south of Mawrth Vallis on Mars. The color is composed of infrared, red, and blue-green color images, and has been enhanced to accentuate the color differences. The bright material may be rich in clays and date back to a time when Mars had a wetter environment. This is a sub-image of a larger view imaged by the High Resolution Imaging Science Experiment (HiRISE) on NASA's Mars Reconnaissance Orbiter on Oct. 1, 2006. The resolution is 25 centimeters (10 inches) per pixel, and the scene is 352 meters (385 yards) wide.

  6. The potential of hydrodynamic analysis for the interpretation of Martian fluvial activities

    NASA Astrophysics Data System (ADS)

    Kim, Jungrack; Schumann, Guy; Neal, Jeffrey; Lin, Shih-Yuan

    2014-05-01

    After liquid water was identified as the agent of ancient Martian fluvial activities, the valley and channels on the Martian surface were investigated by a number of remote sensing and in-situ measurements. In particular, the stereo DTMs and ortho images from various successful orbital sensors are being effectively used to trace the origin and consequences of Martian hydrological channels. For instance, to analyze the Martian fluvial activities more quantitatively using the topographic products, Burr et al. (2003) employed 1D hydrodynamic models such as HEC-RAS together with the topography by MOLA to derive water flow estimates for the Athabasca Valles area on Mars [1]. Where extensive floodplain flows or detailed 2D bathymetry for the river channel exist, it may be more accurate to simulate flows in two dimensions, especially if the direction of flow is unclear a priori. Thus in this study we demonstrated a quantitative modeling method utilizing multi-resolution Martian DTMs, constructed in line with Kim and Muller's (2009) [2] approach, and an advanced hydraulics model LISFLOOD-FP (Bates et al., 2010) [3], which simulates in-channel dynamic wave behavior by solving for 2D shallow water equations without advection. Martian gravitation and manning constants were adjusted in the hydraulic model and the inflow values were iteratively refined from the outputs of the coarser to the finer model. Then we chose the target areas among Martian fluvial geomorphologies and tested the effectiveness of high resolution hydraulic modeling to retrieve the characteristics of fluvial systems. Test sites were established in the Athabasca Valles, Bahram Vallis, and Naktong Vallis respectively. Since those sites are proposed to be originated by different fluvial mechanisms, it is expected that the outputs from hydraulics modeling will provide important clues about the evolution of each fluvial system. Hydraulics modeling in the test areas with terrestrial simulation parameters was also

  7. Volcanic flows versus water- and ice-related outburst deposits in eastern Hellas: A comparison

    NASA Astrophysics Data System (ADS)

    Voelker, M.; Hauber, E.; Stephan, K.; Jaumann, R.

    2018-06-01

    Hellas Planitia is one of the major topographic sinks on Mars for the deposition of any kind of sediments. We report on our observations of sheet deposits in the eastern part of the basin that are apparently related to the Dao Vallis outflow channel. The deposits have lobate flow fronts and a thickness of a few decameters. Despite their generally smooth surface, some distinctive textures and patterns can be identified, such as longitudinal lineations, distributive channels, and polygons. We compared these deposits to other sheet deposits on Mars and tested three hypotheses of their origin: volcanic flows as well as water- and ice-related mass wastings. Despite some similarities to volcanic sheet flows on Mars, we found several morphological characteristics that are not known for sheet lava flows; for example conically arranged lineations and channel systems very similar to fluvial incisions. We also reject an ice-related formation similar to terrestrial rock-ice avalanches, as there is no sufficient relief energy to explain their extent and location. A water-related origin appears most consistent with our observations, and we favor an emplacement by fluvially-driven mass wasting processes, e.g., debris flows. Assuming a water-related origin, we calculated the amount of water that would be required to deposit such large sedimentary bodies for different flow types. Our calculations show a large range of possible water volumes, from 64 to 2,042 km³, depending on the specific flow mechanism. The close link to Dao Vallis makes these deposits a unique place to study the deposition of outflow channel sediments, as the deposits of other outflow channels on Mars, such as those around Chryse Planitia, are mostly buried by younger sediments and volcanic flows.

  8. Abstracts of the Annual Meeting of Planetary Geologic Mappers, San Antonio, TX, 2009

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III (Editor); Tanaka, Kenneth L.; Kelley, Michael S.

    2009-01-01

    Topics covered include: Geologic Mapping of the Beta-Atla-Themis (BAT) Region of Venus: A Progress Report; Geologic Map of the Snegurochka Planitia Quadrangle (V-1): Implications for Tectonic and Volcanic History of the North Polar Region of Venus; Preliminary Geological Map of the Fortuna Tessera (V-2) Quadrangle, Venus; Geological Map of the Fredegonde (V-57) Quadrangle, Venus; Geological Mapping of the Lada Terra (V-56) Quadrangle, Venus; Geologic Mapping of V-19; Lunar Geologic Mapping: A Preliminary Map of a Portion of the LQ-10 ("Marius") Quadrangle; Geologic Mapping of the Lunar South Pole, Quadrangle LQ-30: Volcanic History and Stratigraphy of Schr dinger Basin; Geologic Mapping along the Arabia Terra Dichotomy Boundary: Mawrth Vallis and Nili Fossae, Mars; Geologic Mapping Investigations of the Northwest Rim of Hellas Basin, Mars; Geologic Mapping of the Meridiani Region of Mars; Geology of a Portion of the Martian Highlands: MTMs -20002, -20007, -25002 and -25007; Geologic Mapping of Holden Crater and the Uzboi-Ladon-Morava Outflow System; Mapping Tyrrhena Patera and Hesperia Planum, Mars; Geologic Mapping of Athabaca Valles; Geologic Mapping of MTM -30247, -35247 and -40247 Quadrangles, Reull Vallis Region, Mars Topography of the Martian Impact Crater Tooting; Mars Structural and Stratigraphic Mapping along the Coprates Rise; Geology of Libya Montes and the Interbasin Plains of Northern Tyrrhena Terra, Mars: Project Introduction and First Year Work Plan; Geology of the Southern Utopia Planitia Highland-Lowland Boundary Plain: Second Year Results and Third Year Plan; Mars Global Geologic Mapping: About Half Way Done; New Geologic Map of the Scandia Region of Mars; Geologic Mapping of the Medusae Fossae Formation on Mars and the Northern Lowland Plains of Venus; Volcanism on Io: Insights from Global Geologic Mapping; and Planetary Geologic Mapping Handbook - 2009.

  9. Smectite deposits in Marathon Valley, Endeavour Crater, Mars, identified using CRISM hyperspectral reflectance data

    NASA Astrophysics Data System (ADS)

    Fox, V. K.; Arvidson, R. E.; Guinness, E. A.; McLennan, S. M.; Catalano, J. G.; Murchie, S. L.; Powell, K. E.

    2016-05-01

    The ~100 m wide Marathon Valley crosscuts the Cape Tribulation rim segment of the 22 km diameter, Noachian-age Endeavour impact crater on Mars. Single-scattering albedo spectra retrieved from three Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) Full-Resolution Targeted (FRT, regularized to 18 m/pixel) and two Along Track Oversampled (ATO, regularized to 12 m/pixel) observations indicate the presence of Fe3+-Mg2+ smectite exposures located in Marathon Valley with combination vibration metal-OH absorption strength comparable to smectite spectral signatures in Mawrth Vallis. The Opportunity rover was directed to the exposures and documented the presence of Shoemaker formation impact breccias that have been isochemically altered, likely by fracture-controlled aqueous fluids.

  10. Discovery of columnar jointing on Mars

    USGS Publications Warehouse

    Milazzo, M.P.; Keszthelyi, L.P.; Jaeger, W.L.; Rosiek, M.; Mattson, S.; Verba, C.; Beyer, R.A.; Geissler, P.E.; McEwen, A.S.

    2009-01-01

    We report on the discovery of columnar jointing in Marte Valles, Mars. These columnar lavas were discovered in the wall of a pristine, 16-km-diameter impact crater and exhibit the features of terrestrial columnar basalts. There are discontinuous outcrops along the entire crater wall, suggesting that the columnar rocks covered a surface area of at least 200 km2, assuming that the rocks obliterated by the impact event were similarly jointed. We also see columns in the walls of other fresh craters in the nearby volcanic plains of Elysium Planitia-Amazonis Planitia, which include Marte Vallis, and in a well-preserved crater in northeast Hellas. ?? 2009 The Geological Society of America.

  11. Topography of the northern hemisphere of Mars from the Mars Orbiter Laser Altimeter

    NASA Technical Reports Server (NTRS)

    Smith, D. E.; Zuber, M. T.; Frey, H. V.; Garvin, J. B.; Head, J. W.; Muhleman, D. O.; Pettengill, G. H.; Phillips, R. J.; Solomon, S. C.; Zwally, H. J.; hide

    1998-01-01

    The first 18 tracks of laser altimeter data across the northern hemisphere of Mars from the Mars Global Surveyor spacecraft show that the planet at latitudes north of 50 degrees is exceptionally flat; slopes and surface roughness increase toward the equator. The polar layered terrain appears to be a thick ice-rich formation with a non-equilibrium planform indicative of ablation near the periphery. Slope relations suggest that the northern Tharsis province was uplifted in the past. A profile across Ares Vallis channel suggests that the discharge through the channel was much greater than previously estimated. The martian atmosphere shows significant 1-micrometer atmospheric opacities, particularly in low-lying areas such as Valles Marineris.

  12. Rocky terrain & airbags

    NASA Technical Reports Server (NTRS)

    1997-01-01

    An area of very rocky terrain at the Ares Vallis landing site, along with the lander's deflated airbags, were imaged by the Imager for Mars Pathfinder (IMP) before its deployment on Sol 2. The metallic object at the bottom is a bracket for the IMP's release mechanism.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

  13. General geology and geomorphology of the Mars Pathfinder landing site

    USGS Publications Warehouse

    Ward, A.W.; Gaddis, L.R.; Kirk, R.L.; Soderblom, L.A.; Tanaka, K.L.; Golombek, M.P.; Parker, T.J.; Greeley, Ronald; Kuzmin, R.O.

    1999-01-01

    The Mars Pathfinder (MPF) spacecraft landed on relatively young (late Hesperian-early Amazonian; 3.1-0.7 Ga) plains in Chryse Planitia near the mouth of Ares Vallis. Images returned from the spacecraft reveal a complex landscape of ridges and troughs, large hills and crater rims, rocks and boulders of various sizes and shapes, and surficial deposits, indicating a complex, multistage geologic history of the landing site. After the deposition of one or more bedrock units, depositional and erosional fluvial processes shaped much of the present landscape. Multiple erosional events are inferred on the basis of observations of numerous channels, different orientations of many streamlined tails from their associated knobs and hills, and superposition of lineations and streamlines. Medium- and small-scale features, interpreted to be related to late-stage drainage of floodwaters, are recognized in several areas at the landing site. Streamlined knobs and hills seen in Viking orbiter images support this inference, as they seem to be complex forms, partly erosional and partly depositional, and may also indicate a series of scouring and depositional events that, in some cases, further eroded or partially buried these landforms. Although features such as these are cited as evidence for catastrophic flooding at Ares Vallis, some of these features may also be ascribed to alternative primary or secondary depositional processes, such as glacial or mass-wasting processes. Close inspection of the landing site reveals rocks that are interpreted to be volcanic in origin and others that may be conglomeratic. If such sedimentary rocks are confirmed, fluvial processes have had a greater significance on Mars than previously thought. For the last several hundred million to few billion years, eolian processes have been dominant. Dunes and dune-like features, ventifacts, and deflation and exhumation features around several rocks probably are the most recent landforms. The relatively pristine

  14. Outcrops In Aram Chaos

    NASA Technical Reports Server (NTRS)

    2004-01-01

    16 October 2004 Aram Chaos is the name of an approximately 275 km (171 mi) diameter impact crater near Ares Vallis, roughly half way between the Mars Exploration Rover, Opportunity, site in Meridiani Planum and the easternmost troughs of the Valles Marineris. The Aram Chaos crater is partially filled with a thick accumulation of layered rock. Erosion has exposed light- and dark-toned rock materials in the basin. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small area exhibiting some of the rock outcrops in Aram Chaos. The light-toned rocks may be sedimentary in origin. This image is located near 4.0oN, 20.6oW, and covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the upper left.

  15. What on Mars is a High Thermal-Inertia Surface?

    NASA Image and Video Library

    2015-04-08

    Coprates Chasma is located in the huge canyon system, Vallis Marineris. NASA Mars Reconnaissance Orbiter finds indications of high thermal inertia. What do we mean when we describe a surface as having "high thermal inertia"? The term refers to the ability of a material to conduct and store heat, and in planetary science, its measure of the subsurface's ability to store heat during the day and reradiate it during the night. What causes thermal inertia? It depends on the composition of the terrain that we're studying. Here in Coprates Chasma, the site of this observation, we find indications of such high thermal inertia, so an image at high resolution may help us determine the composition and structure to give us an answer. http://photojournal.jpl.nasa.gov/catalog/PIA19357

  16. Channel geometry and discharge estimates for Dao and Niger Valles, Mars

    NASA Astrophysics Data System (ADS)

    Musiol, S.; van Gasselt, S.; Neukum, G.

    2008-09-01

    Introduction The outflow channels Dao and Niger Valles are located at the eastern rim of the 2000-km diameter Hellas Planitia impact basin, in a transition zone with ancient cratered terrain and the volcanoes Hadriaca and Tyrrhena Patera (Hesperia Planum) on the one hand and fluvial, mass-wasting and aeolian deposits on the other hand [1]. Dao and Niger have alcove-shaped source regions similar to the chaotic terrains found in the Margaritifer Terra region, with flat floors, landslide morphologies and small, chaotically distributed isolated mounds. As [2] pointed out, the intrusion of volcanic material could be responsible for the release of pressurized water that can carry loose material away. This process could than have created a depression and an associated outflow channel. In contrast to [2] who made their calculations for Aromatum Chaos and Ravi Vallis, we have focused on Dao and Niger Valles for investigation, since they are spatially related to the nearby Hadriaca Patera. Heat-triggered outflow events seem likely. We follow the generally accepted assumption that water was the main erosional agent [3]. Furthermore we take into account that multiple floods with different volumes are more likely than a single event because of repressurization of an aquifer [4]. Background Hadriaca Patera Hadriaca Patera is among the oldest central-vent volcanoes on Mars, a low-relief volcano with a central caldera complex which consists predominantly of pyroclastic material. The erosional structure of degraded valleys on its flanks is indicative of dissection by a combination of groundwater sapping and surface runoff, attributed to a hydromagmatic eruption scenario [5]. Dao Vallis Dao Vallis is interpreted as collapse region of volcanic and sedimentary plains that have been eroded by surface and subsurface flow [5]. The approximately radial alignment to Hellas is interpreted as following deep-seated structural weakness zones generated by the impact. Small grabens and fractures

  17. Zephyria Channel System

    NASA Technical Reports Server (NTRS)

    2004-01-01

    10 September 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of an outflow channel system located in the Zephyria region, south of Cerberus, from which vast quantities of rough-surfaced material flowed. The channel system has no name and was not known prior to the MGS mission. The material that flowed through this system may have been extremely fluid lava, or it may have been water-rich mud. Research by members of the Mars science community regarding the nature and origin of flow materials in the Cerberus, Zephyria, and Marte Vallis regions of Mars is on-going. This image is located near 4.6oN, 204.1oW. The image covers an area approximately 3 km (1.9 mi) across and is illuminated by sunlight from the left/lower left.

  18. Ripple Trap

    NASA Technical Reports Server (NTRS)

    2006-01-01

    3 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the margin of a lava flow on a cratered plain in the Athabasca Vallis region of Mars. Remarkably, the cratered plain in this scene is essentially free of bright, windblown ripples. Conversely, the lava flow apparently acted as a trap for windblown materials, illustrated by the presence of the light-toned, wave-like texture over much of the flow. That the lava flow surface trapped windblown sand and granules better than the cratered plain indicates that the flow surface has a rougher texture at a scale too small to resolve in this image.

    Location near: 10.7oN, 204.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  19. A recent, equatorial, periglacial environment on Mars

    NASA Astrophysics Data System (ADS)

    Balme, M. R.; Gallagher, C.; Murray, J. B.; Muller, J.-P.

    2009-04-01

    During the Viking era, Mars' recent climatic history was held to be cold and dry with little evidence for long-lived liquid water near the surface; signs of a past wetter, warmer climate were confined to ancient Noachian or Hesperian-aged terrains. Recent missions have revealed contemporary near-surface water-ice to be abundant at high latitudes, and a population of mid-latitude fluvial-like gullies that appear to have formed by transient melting of ice or snow. Thus today's view of Mars' recent surface evolution is one of global permafrost existing within a framework of climate change, the timescales of which are governed by obliquity cycles with periods of tens to hundreds of thousands of years. However, in recent mapping work of the equatorial Elysium Planitia region using the latest very high resolution images of Mars (HiRISE; 25cm/pixel) we have found evidence for longer-lived, geologically recent liquid water at the martian surface. This suggests that there was a recent period when the climate was warmer than current obliquity cycle-based models predict. The Elysium Planitia region of Mars is both geologically young (late Amazonian period; <100 Ma) and hosts a variety of landforms that are morphologically similar to those of periglacial and permafrost environments on Earth. The region was exposed to massive flooding from deep underground sources during the late Amazonian, as demonstrated by the distinctive fluvial morphologies seen in the outflow channel Athabasca Vallis. These floods would have provided both the source of ice and particulate material required for a periglacial or permafrost landscape and there was probably a long-lived, but slowly freezing, lake or sea in the downstream Elysium basin. However, the provenance of the materials and landforms of this region is disputed: many authors still regard the Athabasca Vallis and Elysium basin as being flood lava provinces, with effusive volcanic materials reoccupying earlier flood landscapes (a classic

  20. Megafans as Hydrous Environments

    NASA Technical Reports Server (NTRS)

    Wilkinson, M. Justin; Miller, R. McG.; Allen, C. C.; Kreslavsky, M. H.; Eckardt, F.

    2009-01-01

    The mesoscale sedimentary environment known as the megafan, is a low-angle, partial cone of fluvial sediment generated where a river enters an unconfined basin where it begins the process of avulsing over wide areas. In shifting to different positions, the river lays down a partial cone of sediment and establishes a characteristic radial pattern of paleo courses. The apparent paucity of sedimentary bodies obviously tied to martian outflow channels may also relate to the difficulty of recognition due to their sheer size and featurelessness. However, the existence of megafans on Mars is being examined now that their ubiquity and characteristics on Earth are better understood. Accordingly we suggest two likely candidates on Mars: Maja Valles fluvial cone and Amazonis Planitia fluvial sedimentary bodies. Two cryptic examples from Amazonis Planitia may be important for understanding subsurface hydrous accumulation. For at least some of its history, discharges from Mangala Valles likely resulted in megafans. Distances from the end of Mangala Valles to the northern (low) margin of the planitia are very large, a fact that has suggested that fluvial emplacement was unlikely. However, the megafan model shows that long megafan radii are indeed feasible. It has been suggested further that discharge from Labou Vallis (8.5S 154.5W) must have led to fluvial sedimentation in the planitia. We suggest that during locally non-lacustrine/ocean phases, this sedimentation would have occurred in the form of megafans. However, the megafan model shows that long megafan radii are indeed feasible. It has been suggested further that discharge from Labou Vallis (8.5S 154.5W) must have led to fluvial sedimentation in the planitia. We suggest that during locally non-lacustrine/ocean phases, this sedimentation would have occurred in the form of megafans. Megafans emanating from Marte, Mangala and Labou valles have probably contributed to hydrous near-subsurface environments--in their distal

  1. Physical Diversity of Phyllosilicate Deposits at the MSL Candidate Landing Sites

    NASA Astrophysics Data System (ADS)

    Fergason, R. L.

    2008-12-01

    The identification of phyllosilicates on Mars implies aqueous activity at the time of their formation and is important for understanding the history of Martian water and the past habitability of Mars. In addition, a significant fraction of the global water budget of Mars may be locked into clay mineral deposits within the Martian crust. As a result, six out of seven final landing sites being considered for the Mars Science Laboratory are sites where phyllosilicates have been identified in CRISM and OMEGA data. The physical characteristics of these materials, as identified using thermal inertia data, are an important component for understanding the geologic history of these deposits. Thermal inertia values provide information regarding effective particle size and help to constrain the possible presence of duricrust, rocks, and exposed bedrock at these locations. These identified physical characteristics suggest the degree of resistivity to erosion, which has implications for the post-emplacement modification of these deposits. At the aforementioned six locations (Nili Fossae Trough, Holden Crater, Mawrth Vallis, Miyamoto crater, southern Meridiani Planum, and Gale crater) the physical properties were quantified using THEMIS-derived thermal inertia data to characterize the physical properties at each site and identify the presence or absence of physical diversity among these materials. I identified a wide range of surface properties at these locations ranging from indurated surfaces intermixed with unconsolidated aeolian material (thermal inertia of 150-460 J m-2 K-1 s- 1/2) at Mawrth Vallis, to exposures of in-place bedrock and the presence of rocky material (thermal inertia exceeding 800 J m-2 K-1 s-1/2) in Gale crater. In addition, the surface texture and morphologic features observed in high-resolution visible images (such as narrow-angle MOC, HiRISE, and CTX) are dissimilar across these phyllosilicate exposures, and confirm the interpretation of thermal inertia

  2. Authentic Mars Research in the High School

    NASA Astrophysics Data System (ADS)

    Kortekaas, Katie; Leach, Dani

    2015-01-01

    As a 11th and 12th grade Astrobiology class we were charged with developing a scientific research question about the potential for life on Mars. We narrowed our big picture question to, 'Where should the next Mars rover land in order to study the volcanic and water features to find evidence of past or present extremophiles on Mars?'After a lot of searching through images on JMARS (although not extensive due to high school time constraints) we narrowed our interest to three areas of Mars we thought could be good candidates to land a rover there to do further research. We know from extremophiles on Earth that microscopic life need water and energy. It seems reasonable that Mars would be no different. We developed a research question, 'Does Kasei Valles, Dzigai Vallis and Hecate Tholus have volcanic features (lava flow, fractures, volcanoes, cryovolcanoes) and water features (layers of ice, hematite, carbonate, chaos)?'This question is important and interesting because by having a deeper understanding of whether these places have evidence of volcanic and water features, we will be able to decide where the best place to land a future rover would be. Evidence of volcanic and water features are important to help determine where to land our rover because in those areas, temperatures could have been warm and the land could be wet. In these conditions, the probability of life is higher.We individually did research through JMARS (CTX, THEMIS) in order to establish if those three areas could contain certain land features (volcanic and water features) that could possibly lead to the discovery of extremophiles. We evaluated the images to determine if the three areas have evidence of those volcanic and water features.Although we are not experts at identifying features we believe we have evidence to say that all three areas are interesting, astrobiologically, but Dzigai Vallis shows the most number of types of volcanic and water features. More importantly, through this process we

  3. Prospecting from Orbit

    NASA Image and Video Library

    2017-09-04

    The combination of morphological and topographic information from stereo images from NASA's Mars Reconnaissance Orbiter, as well as compositional data from near-infrared spectroscopy has been proven to be a powerful tool for understanding the geology of Mars. Beginning with the OMEGA instrument on the European Space Agency's Mars Express orbiter in 2003, the surface of Mars has been examined at near-infrared wavelengths by imaging spectrometers that are capable of detecting specific minerals and mapping their spatial extent. The CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) instrument on our orbiter is a visible/near-infrared imaging spectrometer, and the HiRISE camera works together with it to document the appearance of mineral deposits detected by this orbital prospecting. Mawrth Vallis is one of the regions on Mars that has attracted much attention because of the nature and diversity of the minerals identified by these spectrometers. It is a large, ancient outflow channel on the margin of the Southern highlands and Northern lowlands. Both the OMEGA and CRISM instruments have detected clay minerals here that must have been deposited in a water-rich environment, probably more than 4 billion years ago. For this reason, Mawrth Vallis is one of the two candidate landing sites for the future Mars Express Rover Mission planned by the European Space Agency. This image was targeted on a location where the CRISM instrument detected a specific mineral called alunite, KAl3(SO4)2(OH)6. Alunite is a hydrated aluminum potassium sulfate, a mineral that is notable because it must have been deposited in a wet acidic environment, rich in sulfuric acid. Our image shows that the deposit is bright and colorful, and extensively fractured. The width of the cutout is 1.2 kilometers. The map is projected here at a scale of 50 centimeters (19.7 inches) per pixel. [The original image scale is 60.1 centimeters (23.7 inches) per pixel (with 2 x 2 binning); objects on the order

  4. The geologic history of Margaritifer basin, Mars

    USGS Publications Warehouse

    Salvatore, M. R.; Kraft, M. D.; Edwards, Christopher; Christensen, P.R.

    2016-01-01

    In this study, we investigate the fluvial, sedimentary, and volcanic history of Margaritifer basin and the Uzboi-Ladon-Morava (ULM) outflow channel system. This network of valleys and basins spans more than 8000 km in length, linking the fluvially dissected southern highlands and Argyre Basin with the northern lowlands via Ares Vallis. Compositionally, thermophysically, and morphologically distinct geologic units are identified and are used to place critical relative stratigraphic constraints on the timing of geologic processes in Margaritifer basin. Our analyses show that fluvial activity was separated in time by significant episodes of geologic activity, including the widespread volcanic resurfacing of Margaritifer basin and the formation of chaos terrain. The most recent fluvial activity within Margaritifer basin appears to terminate at a region of chaos terrain, suggesting possible communication between surface and subsurface water reservoirs. We conclude with a discussion of the implications of these observations on our current knowledge of Martian hydrologic evolution in this important region.

  5. Acidalia and Chryse Plains, Mars

    NASA Image and Video Library

    2000-06-14

    Somewhere down there sits the Mars Pathfinder lander and Sojourner rover. This Mars Global Surveyor Mars Orbiter Camera view of the red planet shows the region that includes Ares Vallis and the Chryse Plains upon which both Mars Pathfinder and the Viking 1 landed in 1997 and 1976, respectively. Acidalia Planitia is the dark surface that dominates the center left. The Pathfinder site is immediately south of Acidalia, just left of center in this view. Also shown--the north polar cap is at the top, and Arabia Terra and Sinus Meridiani are to the right. The bluish-white features are clouds. This is a color composite of 9 red and 9 blue image strips taken by the Mars Global Surveyor Mars Orbiter Camera on 9 successive orbits from pole-to-pole during the calibration phase of the mission in March 1999. The color is computer-enhanced and is not shown as it would actually appear to the human eye. http://photojournal.jpl.nasa.gov/catalog/PIA02000

  6. On the Testing of Renovations Inside Historical Opera Houses

    NASA Astrophysics Data System (ADS)

    Fausti, P.; Prodi, N.

    2002-11-01

    Due to the large number of historical opera houses in Italy, many theatres have been renovated in the past, but still more will undergo major restoration in the near future. Unfortunately in this context, the quality and protection of acoustics is rarely considered as an issue of its own. As a consequence, the renovations are hardly ever accompanied by proper scientific and technical support. In this paper, the acoustical impact of works inside the Teatro Municipale "R.Valli" in Reggio Emilia, including the restoration of the main hall and the construction of a new acoustic shell, will be dealt with. Surveys were held in the theatre before renovation and were repeated with identical procedure and instruments after its completion. By means of a comparative analysis of the architectural project and of acoustical data, the impact of major changes in the theatre can be predicted. It is shown that this approach can help in drafting an operational scheme for safeguarding the acoustics of historical opera houses.

  7. The geologic history of Margaritifer basin, Mars

    NASA Astrophysics Data System (ADS)

    Salvatore, M. R.; Kraft, M. D.; Edwards, C. S.; Christensen, P. R.

    2016-03-01

    In this study, we investigate the fluvial, sedimentary, and volcanic history of Margaritifer basin and the Uzboi-Ladon-Morava outflow channel system. This network of valleys and basins spans more than 8000 km in length, linking the fluvially dissected southern highlands and Argyre basin with the northern lowlands via Ares Vallis. Compositionally, thermophysically, and morphologically distinct geologic units are identified and are used to place critical relative stratigraphic constraints on the timing of geologic processes in Margaritifer basin. Our analyses show that fluvial activity was separated in time by significant episodes of geologic activity, including the widespread volcanic resurfacing of Margaritifer basin and the formation of chaos terrain. The most recent fluvial activity within Margaritifer basin appears to terminate at a region of chaos terrain, suggesting possible communication between surface and subsurface water reservoirs. We conclude with a discussion of the implications of these observations on our current knowledge of Martian hydrologic evolution in this important region.

  8. Relative Time-scale for Channeling Events Within Chaotic Terrains, Margaritifer Sinus, Mars

    NASA Technical Reports Server (NTRS)

    Janke, D.

    1985-01-01

    A relative time scale for ordering channel and chaos forming events was constructed for areas within the Margaritifer Sinus region of Mars. Transection and superposition relationships of channels, chaotic terrain, and the surfaces surrounding them were used to create the relative time scale; crater density studies were not used. Channels and chaos in contact with one another were treated as systems. These systems were in turn treated both separately (in order to understand internal relationships) and as members of the suite of Martian erosional forms (in order to produce a combined, master time scale). Channeling events associated with chaotic terrain development occurred over an extended geomorphic period. The channels can be divided into three convenient groups: those that pre-date intercrater plains development post-plains, pre-chasma systems; and those associated with the development of the Vallis Marineris chasmata. No correlations with cyclic climatic changes, major geologic events in other regions on Mars, or triggering phenomena (for example, specific impact events) were found.

  9. The University Scientist's Role in Promoting Collaborative K-12 Professional Development

    NASA Astrophysics Data System (ADS)

    Schuster, D.; Brown, L. L.; Carlsen, W. S.

    2004-12-01

    Comprehensive K-12 science teacher professional development is dependent upon the successful interaction between the university and K-12 communities (National Research Council, 2001), which can be realized through partnerships between university scientists and K-12 science teachers. This paper will identify some best practices of university scientists in the professional development of science teachers, first by citing the professional development and science education literature (Loucks-Horsley, Hewson, Love, & Stiles, 1998; National Research Council, 1996a, 1996b), and then by highlighting how these best practices were actualized in summer workshops for science educators offered at Penn State. Each summer the Pennsylvania Space Grant Consortium supports seven one-week courses for secondary science teachers taught by university scientists from disciplines representative of NASA's research interests. Approximately 100 teachers enroll in these two-credit, graduate-level workshops from a variety of locations and contexts throughout the United States. These summer courses share a number of important features (duration, general format, teacher recruitment and admission, location, number of participants, etc.), making them a unique dataset for comparative research on science teacher professional development. By recognizing the role of university scientists relating to both practice and standards of professional development, we identify areas in which teachers could be empowered to lead and, alternatively, where scientists and administrators should improve and continue to direct-- both supporting a culture of collaboration that builds K-12 science teacher capacity (Fullan, 2001, 2003; Hawley & Valli, 1999). In our observations and analysis of the evaluations, three best practices, as defined by the literature, appeared to distinguish the exceptional workshops: First, teachers give high marks and make affirmative comments about workshops with clearly presented curricular

  10. ExoMars 2018: the four final candidate Landing Sites

    NASA Astrophysics Data System (ADS)

    Loizeau, Damien; Flahaut, Jessica; Vago, Jorge L.; Hauber, Ernst; Bridges, John C.

    2015-04-01

    December 2014. The Aram Dorsum site comprises Noachian layered sedimentary rocks with a prominent inverted channel system (>80 km long). Potential targets include the inverted channel, the channel margins, a channel transition unit, and pits present within the floodplain. The Hypanis Vallis site lies near two fluvial fan/deltaic systems at the termination of Hypanis and Sabrina Valles. Potential targets include mainly outcrops of expected fine-grained sediments on the smooth transition unit that surrounds the delta/fan, and units around the rim of Magong crater. The Mawrth Vallis site contains one of the largest exposures of phyllosilicates detected on the Martian surface, in Noachian terrain [8]. Potential targets include the mineralogically diverse clay-rich outcrops and ancient channels. The Oxia Planum site lies on Fe/Mg phyllosilicates-rich exposures associated to layered rocks that may be related to the Mawrth Vallis sequence. Potential targets include the clay-rich outcrops as well as channels and inverted channels and delta-fan deposits. New data are being actively acquired by the HiRISE, CRISM and HRSC teams to support the ExoMars 2018 landing site selection process. The ellipses are large and new data are important for characterizing the potential targets and evaluating the safety of the sites. The proposing teams, the ExoMars project team and the LSSWG will continue their analysis and comparison of the sites, aiming to complete the certification of at least one site by September 2016 -- in time for the start of the mission's Critical Design Review (CDR). The final selection of the landing site is expected within 2017. References: [1] http://exploration.esa.int/mars/48088-mission-overview/ [2] http://exploration.esa.int/mars/53462-call-for-exo mars-2018-landing-site-selection/ [3] ExoMars 2018 LSSWG recommendation: http://exploration.esa.int/mars/54707-recommendation-for-the-narrowing-of-exomars-2018-landing-sites/

  11. Assessing Layered Materials in Gale Crater

    NASA Technical Reports Server (NTRS)

    Bridges, N. T.

    2001-01-01

    The recent analysis of high resolution Mars Orbiter Camera (MOC) images of layered outcrops in equatorial regions reinforces two important ideas, which will probably eventually become paradigms, about Mars: 1) It has had a long, complex geologic history marked by change, as manifested in the different layers observed, and 2) Standing bodies of water existed for substantial lengths of time, indicating clement conditions possibly conducive to life. Although observations of layering and evidence for lakes and oceans has been reported for years based on Mariner 9 and Viking data, the MOC data show that this layering is much more pervasive and complex than previously thought. These layered sites are ideal for studying the geologic, and possibly biologic, history of Mars. Here, a layered site within Gale Crater is advocated as a Mars Exploration Rover (MER) target. This is one of the few layered areas within closed depressions (e.g., other craters and Vallis Marineris) that meets the landing site constraints and is accessible to both MER A and B.

  12. Valine Supplementation in a Reduced Protein Diet Regulates Growth Performance Partially through Modulation of Plasma Amino Acids Profile, Metabolic Responses, Endocrine, and Neural Factors in Piglets.

    PubMed

    Zhang, Xiaoya; Liu, Xutong; Jia, Hongmin; He, Pingli; Mao, Xiangbing; Qiao, Shiyan; Zeng, Xiangfang

    2018-03-28

    The objective of this study was to investigate whether valine (Val) supplementation in a reduced protein (RP) diet regulates growth performance associated with the changes in plasma amino acids (AAs) profile, metabolism, endocrine, and neural system in piglets. Piglets or piglets with a catheter in the precaval vein were randomly assigned to two treatments, including two RP diets with standardized ileal digestible (SID) Val:Lysine (Lys) ratio of 0.45 and 0.65, respectively. The results indicated that piglets in the higher Val:Lys ratio treatment had higher average daily feed intake (ADFI) ( P < 0.001), average daily gain (ADG) ( P = 0.001), feed conversion ratio (FCR) ( P = 0.004), lower plasma urea nitrogen ( P = 0.032), expression of gastric cholecystokinin (CCK), and hypothalamic pro-opiomelanocortin (POMC). Plasma AAs profiles including postprandial plasma essential AAs (EAAs) profile and in serum, muscle, and liver involved in metabolism of AAs and fatty acids were significantly different between two treatments. In conclusion, Val influenced growth performance associated with metabolism of AAs and fatty acids and both endocrine and neural system in piglets.

  13. Surficial Geology of the Spirit Rover Traverse in Gusev Crater: Dry and Desiccating Since the Hesperian

    NASA Technical Reports Server (NTRS)

    Golombek, M. P.

    2004-01-01

    The Spirit rover landed successfully in a low albedo portion of Gusev crater at 14.5692 deg S, 175.4729 deg E on January 3, 2004 and has traversed about 3.5 km over 180 sols through cratered plains to Bonneville crater and the Columbia Hills. Gusev, a 160 km diameter Noachian crater that lies at the terminus of the 900 km long Ma'adim Vallis, was selected as a landing site to search for evidence of previous liquid water flow and/or ponding. Although no clear evidence of fluvial or lacustrine activity has been identified in the cratered plains (excepting rocks in the Columbia Hills), their surficial geology strongly limits any warmer and/or wetter period of Mars history (e.g., observed at Meridiani Planum) to be pre-Late Hesperian. This paper will review the surficial geology of Gusev crater as observed along the traverse by Spirit with special reference to the derived gradation history that strongly argues for a dry and desiccating environment since the Late Hesperian.

  14. Abstracts of the Annual Meeting of Planetary Geologic Mappers, Flagstaff, AZ, 2008

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III (Editor); Tanaka, Kenneth L. (Editor); Kelley, Michael S. (Editor)

    2008-01-01

    Topics discussed include: Merging of the USGS Atlas of Mercury 1:5,000,000 Geologic Series; Geologic Mapping of the V-36 Thetis Regio Quadrangle: 2008 Progress Report; Structural Maps of the V-17 Beta Regio Quadrangle, Venus; Geologic Mapping of Isabella Quadrangle (V-50) and Helen Planitia, Venus; Renewed Mapping of the Nepthys Mons Quadrangle (V-54), Venus; Mapping the Sedna-Lavinia Region of Venus; Geologic Mapping of the Guinevere Planitia Quadrangle of Venus; Geological Mapping of Fortuna Tessera (V-2): Venus and Earth's Archean Process Comparisons; Geological Mapping of the North Polar Region of Venus (V-1 Snegurochka Planitia): Significant Problems and Comparisons to the Earth's Archean; Venus Quadrangle Geological Mapping: Use of Geoscience Data Visualization Systems in Mapping and Training; Geologic Map of the V-1 Snegurochka Planitia Quadrangle: Progress Report; The Fredegonde (V-57) Quadrangle, Venus: Characterization of the Venus Midlands; Formation and Evolution of Lakshmi Planum (V-7), Venus: Assessment of Models using Observations from Geological Mapping; Geologic Map of the Meskhent Tessera Quadrangle (V-3), Venus: Evidence for Early Formation and Preservation of Regional Topography; Geological Mapping of the Lada Terra (V-56) Quadrangle, Venus: A Progress Report; Geology of the Lachesis Tessera Quadrangle (V-18), Venus; Geologic Mapping of the Juno Chasma Quadrangle, Venus: Establishing the Relation Between Rifting and Volcanism; Geologic Mapping of V-19, V-28, and V-53; Lunar Geologic Mapping Program: 2008 Update; Geologic Mapping of the Marius Quadrangle, the Moon; Geologic Mapping along the Arabia Terra Dichotomy Boundary: Mawrth Vallis and Nili Fossae, Mars: Introductory Report; New Geologic Map of the Argyre Region of Mars; Geologic Evolution of the Martian Highlands: MTMs -20002, -20007, -25002, and -25007; Mapping Hesperia Planum, Mars; Geologic Mapping of the Meridiani Region, Mars; Geology of Holden Crater and the Holden and Ladon Multi

  15. A Comparison of Large-Scale Reforestation Techniques Commonly Used on Abandoned Fields in the Lower Mississippi Alluvial Vally

    Treesearch

    Callie Jo Schweitzer; John A. Stanturf

    1999-01-01

    Reforesting abandoned land in the lower Mississippi alluvial valley has attracted heightened attention. Currently, federal cost share programs, such as the Wetland Reserve Program and the Conservation Reserve Program, are enticing landowners to consider reforesting lands that are marginally productive for agriculture. This study examined four reforestation techniques...

  16. Spirit at Gusev Crater: Preliminary Observations, Potential Processes and Hypotheses

    NASA Technical Reports Server (NTRS)

    Cabrol, N. A.; desMarais, D.; Farmer, J.; Crumpler, L.; Grin, E. A.; Milam, K.; Grant, J.; Greeley, R.; Anderson, R. C.; Grotzinger, J.

    2004-01-01

    Spirit landed in a flat plain in Gusev crater with local undulations at meters scales generated by ridges covered with blocks, some of them looking rounded. Several, flat-topped, mesas are visible in the far field in direction of Ma adim Vallis. A set of north/south oriented hills reaches approximately 150 m elevation to the east of the landing site (LS). A dipping brighter unit with possibly some scarps is associated with it. This setting could be consistent with layering observed on the MOC images of the hills, local exposure of material with variable dust cover, or deflated or allochtonous material. Numerous small depressions are visible from LS referred to as "Columbia Memorial Station"* (CMS). Floors are partially filled with finer-grained, high albedo material. At least one of them, nicknamed "Sleepy Hollow"* (approximately 30 m diameter) may be an eroded secondary impact crater. It is unclear if they can all be related to small impact structures. Some of them are elongated and aligned with the ridges. The morphology of rocks and soil at this Gusev Crater is presented. Evidence of dynamic aeolian action along this Crater is also discussed.

  17. Insights Into the Aqueous History of Mars from Acid-Sulfate Weathered Phyllosilicates

    NASA Technical Reports Server (NTRS)

    Craig, P. I.; Ming, D. W.; Rampe, E. B.; Morris, R. V.

    2016-01-01

    Phyllosilicates on Mars are thought to have formed during Mars' earliest Noachian geologic era (approx. 4.1-3.7 Ga). Sulfate formation, on the other hand, requires more acidic conditions which are thought to have occurred later during Mars' Hesperian era (approx. 3.7-3.0 Ga). Therefore, regions on Mars where phyllosilicates and sulfates are found in close proximity to each other provide evidence for the aqueous conditions during this global transition. Both phyllosilicates and sulfates form in the presence of water and thus give clues to the aqueous history of Mars and its potential for habitability. Phyllosilicates that formed during the Noachian era would have been weathered by the prevailing acidic conditions that define the Hesperian. Therefore, the purpose of this study is to characterize the alteration products of acid-sulfate weathered phyllosilicates in laboratory experiments, focusing on the Fe/Mg-smectites commonly identified on Mars. We also compare our results to observations of phyllosilicates and sulfates on Mars in regions such as Endeavour Crater and Mawrth Vallis to understand the formation process of sulfates and constrain the aqueous history of these regions.

  18. Sulfate Formation From Acid-Weathered Phylosilicates: Implications for the Aqueous History of Mars

    NASA Technical Reports Server (NTRS)

    Craig, P. I.; Ming, D. W.; Rampe, E. B.

    2014-01-01

    Most phyllosilicates on Mars are thought to have formed during the planet's earliest Noachian era, then Mars underwent a global change making the planet's surface more acidic [e.g. 1]. Prevailing acidic conditions may have affected the already existing phyllosilicates, resulting in the formation of sulfates. Both sulfates and phyllosilicates have been identified on Mars in a variety of geologic settings [2] but only in a handful of sites are these minerals found in close spatial proximity to each other, including Mawrth Vallis [3,4] and Gale Crater [5]. While sulfate formation from the acidic weathering of basalts is well documented in the literature [6,7], few experimental studies investigate sulfate formation from acid-weathered phyllosilicates [8-10]. The purpose of this study is to characterize the al-teration products of acid-weathered phyllosilicates in laboratory experiments. We focus on three commonly identified phyllosilicates on Mars: nontronite (Fe-smectite), saponite (Mg-smectite), and montmorillonite (Al-smectite) [1, and references therein]. This information will help constrain the formation processes of sulfates observed in close association with phyllosilicates on Mars and provide a better understanding of the aqueous history of such regions as well as the planet as a whole.

  19. Neurolinguistic programming training, trait anxiety, and locus of control.

    PubMed

    Konefal, J; Duncan, R C; Reese, M A

    1992-06-01

    Training in the neurolinguistic programming techniques of shifting perceptual position, visual-kinesthetic dissociation, timelines, and change-history, all based on experiential cognitive processing of remembered events, leads to an increased awareness of behavioral contingencies and a more sensitive recognition of environmental cues which could serve to lower trait anxiety and increase the sense of internal control. This study reports on within-person and between-group changes in trait anxiety and locus of control as measured on the Spielberger State-Trait Anxiety Inventory and Wallston, Wallston, and DeVallis' Multiple Health Locus of Control immediately following a 21-day residential training in neurolinguistic programming. Significant with-in-person decreases in trait-anxiety scores and increases in internal locus of control scores were observed as predicted. Chance and powerful other locus of control scores were unchanged. Significant differences were noted on trait anxiety and locus of control scores between European and U.S. participants, although change scores were similar for the two groups. These findings are consistent with the hypothesis that this training may lower trait-anxiety scores and increase internal locus of control scores. A matched control group was not available, and follow-up was unfortunately not possible.

  20. Diabetes-Related Behavior Change Knowledge Transfer to Primary Care Practitioners and Patients: Implementation and Evaluation of a Digital Health Platform.

    PubMed

    Abidi, Samina; Vallis, Michael; Piccinini-Vallis, Helena; Imran, Syed Ali; Abidi, Syed Sibte Raza

    2018-04-18

    delivered through a mobile patient diary via mobile phones and tablets. DWISE has been tested for its usability, functionality, usefulness, and acceptance through a series of qualitative studies. For the primary care practitioner tool, most usability problems were associated with the navigation of the tool and the presentation, formatting, understandability, and suitability of the content. For the patient tool, most issues were related to the tool's screen layout, design features, understandability of the content, clarity of the labels used, and navigation across the tool. Facilitators and barriers to DWISE use in a shared decision-making environment have also been identified. This work has provided a unique electronic health solution to translate complex health care knowledge in terms of easy-to-use, evidence-informed, point-of-care decision aids for primary care practitioners. Patients' feedback is now being used to make necessary modification to DWISE. ©Samina Abidi, Michael Vallis, Helena Piccinini-Vallis, Syed Ali Imran, Syed Sibte Raza Abidi. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 18.04.2018.

  1. Evaluation of Actual Nitrogen Losses From a Watershed Preliminary Results of a Case Study in the Po Vally (Northern Italy)

    Treesearch

    Maurizio Borin; Tomaso Bisol; Gabriele Bonaiti; Francesco Morari; Devendra M. Amatya

    2004-01-01

    The evaluation of potential N losses from individual fields is not sufficient to provide an estimate of the actual nitrogen loads reaching the main watercourses and therefore becoming a relevant source of pollution. Along the travel path from a field to the outlet of a watershed several biogeochemical processes may occur, leading to significant changes in the N amount...

  2. Topographic map of the western region of Dao Vallis in Hellas Planitia, Mars; MTM 500k -40/082E OMKT

    USGS Publications Warehouse

    Rosiek, Mark R.; Redding, Bonnie L.; Galuszka, Donna M.

    2006-01-01

    This map, compiled photogrammetrically from Viking Orbiter stereo image pairs, is part of a series of topographic maps of areas of special scientific interest on Mars. Contours were derived from a digital terrain model (DTM) compiled on a digital photogrammetric workstation using Viking Orbiter stereo image pairs with orientation parameters derived from an analytic aerotriangulation. The image base for this map employs Viking Orbiter images from orbits 406 and 363. An orthophotomosaic was created on the digital photogrammetric workstation using the DTM compiled from stereo models.

  3. Exploring Gusev Crater with Spirit: Review of science objectives and testable hypotheses

    USGS Publications Warehouse

    Cabrol, N.A.; Grin, E.A.; Carr, M.H.; Sutter, B.; Moore, Johnnie N.; Farmer, J.D.; Greeley, R.; Kuzmin, R.O.; DesMarais, D.J.; Kramer, M.G.; Newsom, H.; Barber, C.; Thorsos, I.; Tanaka, K.L.; Barlow, N.G.; Fike, D.A.; Urquhart, M.L.; Grigsby, B.; Grant, F.D.; de Goursac, O.

    2003-01-01

    Gusev Crater was selected as the landing site for the Mars Exploration Rover (MER) Spirit mission. Located at the outlet of Ma'adim Vallis and 250 km south of the volcano Apollinaris Patera, Gusev is an outstanding site to achieve the goals of the MER mission. The crater could have collected sediments from a variety of sources during its 3.9 Ga history, including fluvial, lacustrine, volcanic, glacial, impact, regional and local aeolian, and global air falls. It is a unique site to investigate the past history of water on Mars, climate and geological changes, and the potential habitability of the planet, which are central science objectives of the MER mission. Because of its complex history and potential diversity, Gusev will allow the testing of a large spectrum of hypotheses with the complete suite of MER instruments. Evidence consistent with long-lived lake episodes exist in the landing ellipse area. They might offer a unique opportunity to study, for the first time, Martian aqueous sediments and minerals formed in situ in their geological context. We review the geological history and diversity of the landing site, the science hypotheses that can be tested during the MER mission, and the relevance of Gusev to the MER mission objectives and payload. Copyright 2003 by the American Geophysical Union.

  4. Observations at the Mars Pathfinder site: Do they provide "unequivocal" evidence of catastrophic flooding?

    USGS Publications Warehouse

    Chapman, M.G.; Kargel, J.S.

    1999-01-01

    After Mars Pathfinder landed at the mouth of Ares Vallis, a large channel that drains into the Chryse Planitia basin, the mission reports unanimously supported the interpretation that the lander site is the locus of catastrophic flooding by noting that all aspects of the scene are consistent with this interpretation. However, alternatives cannot be ruled out by any site observations, as all aspects of the scene are equally consistent with other interpretations of origin, namely, ice and mass-flow processes subsequently modified by wind erosion. The authors discuss alternative explanations for the geologic history of the channel based on a regional view of the circum-Chryse channels from Viking images (our best broad-scale information to date) and the local view from the recent Pathfinder landing site. Mega-indicators of channel origin, the regional geomorphology, geology, and planetary climatic conditions, taken together suggest some combination of flood, mass flow, glacial, and eolian processes. The macro-indicators of channel origin (sedimentologic) are also not indicative of one process of emplacement, either as single criteria or taken cumulatively. Finally, the micro-indicators of channel origin (geochemical and mineralogic composition) do not provide very tight constraints on the deposits' possible origins other than that water was in some way involved.

  5. Mars Pathfinder Landing Site: Evidence for a Change in Wind Regime from Lander and Orbiter Data

    NASA Technical Reports Server (NTRS)

    Greeley, Ronald; Kraft, Michael D.; Kuzmin, Ruslan O.; Bridges, Nathan T.

    2000-01-01

    Surface features related to the wind are observed in the vicinity of the Mars Pathfinder (MPR landing site data from the lander and in data from orbit by the Viking Orbiter and Mars Global Surveyor missions. Features seen from the surface include wind tails associated with small rocks, barchanoid duneforms, ripplelike patterns, and ventifact flutes cut into some rocks. Features seen from orbit include wind tails associated with impact craters, ridges inferred to be duneforms, and modified crater rims interpreted to have been eroded and mantled by windblown material. The orientations of these features show two prevailing directions. One is inferred to represent winds from the northeast, which is consistent with strongest winds predicted by a general circulation model to occur during the Martian northern winter under current conditions. A second wind blowing from the ESE was responsible for modifying the crater rims and cutting some of the ventifacts. The two wind regimes could reflect a change in climate related to Mars' obliquity or some other, unknown factor. Regardless of the cause, the MPF area has been subjected to a complex pattern of winds and supply of small particles, and the original surface formed by sedimentary processes from Tiu and Ares Vallis flooding events has been modified by repeated burial and exhumation.

  6. Origins of Sinuous and Braided Channels on Ascraeus Mons, Mars - A Keck Geology Consortium Undergraduate Research Project

    NASA Technical Reports Server (NTRS)

    de Wet, A. P.; Bleacher, J. E.; Garry, W. B.

    2012-01-01

    Water has clearly played an important part in the geological evolution of Mars. There are many features on Mars that were almost certainly formed by fluvial processes -- for example, the channels Kasei Valles and Ares Vallis in the Chryse Planitia area of Mars are almost certainly fluvial features. On the other hand, there are many channel features that are much more difficult to interpret -- and have been variously attributed to volcanic and fluvial processes. Clearly unraveling the details of the role of water on Mars is extremely important, especially in the context of the search of extinct or extant life. In this project we built on our recent work in determining the origin of one channel on the southwest rift apron of Ascraeus Mons. This project, funded by the Keck Geology Consortium and involving 4 undergraduate geology majors took advantage of the recently available datasets to map and analyze similar features on Ascraeus Mons and some other areas of Mars. A clearer understanding of how these particular channel features formed might lead to the development of better criteria to distinguish how other Martian channel features formed. Ultimately this might provide us with a better understanding of the role of volcanic and fluvial processes in the geological evolution of Mars.

  7. Planning a new type of cultural community space in Goyang City, Korea

    NASA Astrophysics Data System (ADS)

    Kim, Jeonghye; Kim, Saehoon

    2017-12-01

    Between March and June 2017, Seoul National University Graduate School of Environment Studies and Goyang City organized a course titled ‘Environment Design and Planning’. At the beginning stage of the project, even though the Unified Korean Silicon Vally Project was initiated, our team members in the class decide to reconsider whether a large redevelopment project aimed at attracting tourists is actually a desirable goal for the residents or not. What would be truly needed for space users living in the area? How should we preserve and maintain the existing meaningful space? Meanwhile, we come up with the Gyeongui Railroad, which passes through Goyang and Ilsan. It was a railway line that shared memories of the past, the daily lives of the residents, and the joys and sorrows of them. Among the railways, ‘Baek-Ma Station’ was the place which was filled with the memories of the people who spent their youth in the city in the 1980s. The station is currently not in use, because this place is abandoned and empty. We wished to make this space more accessible for the residents and also to create a place that would give an opportunity to the resident's social comeback. The space could be activated again with the revival of local cultural activities. And we hope the residents will be able to create new memories of 2017 in this space.

  8. The Effect of Gaseous Ozone in Infected Root Canal

    PubMed Central

    Ajeti, Nova Nexhmije; Pustina-Krasniqi, Teuta; Apostolska, Sonja

    2018-01-01

    OBJECTIVES: During the treatment of chronic apical periodontitis and pulp necrosis the main role is to irrigate the root canal. AIM: The aim of this in vivo study was to irrigate with 0.9% NaCl (Natrium Chloride), 2.5 % NaOCl (Sodium Hypochlorite Solution, Sigma Aldrich - Germany) and 2% CHX (Chlorhexidine Digluconate Solution, Sigma Aldrich - Spain) combined with Gaseous Ozone (Prozone WH, Austria). MATERIAL AND METHODS: This study was realised in the University Dentistry Clinical Centre of Kosovo (UDCCK), respectively in the Department of Endodontic and Dental Pathology, Dental Branch, Faculty of Medicine, Prishtina, Kosovo. The 40 subjects involved in this study belonged to both genders, in age between 15 -65 years. The sample selection was randomised. The retroalveolar radiography for each patient was taken in the suspected tooth. As a therapeutic plan the authors decided to disinfect the root canal with the irrigants, as follows: 2.5 % NaOCl, 2 % CHX and gaseous ozone. RESULTS: The statistical analyses were based on Kruskal - Vallis test, X - test, DF = 3, r < 0.01. In the isolated average number of the aerobe and anaerobe bacteria colonies, when gaseous ozone was used, there was the significant statistical difference. CONCLUSIONS: When gaseous ozone was combined with irrigants 0.9%, 2.5 % NaOCl and 2% CHX, it was concluded that the number of colonies of aerobic and anaerobic bacteria was reduced. PMID:29531611

  9. Meter-Scale Characteristics of Martian Channels and Valleys

    USGS Publications Warehouse

    Carr, M.H.; Malin, M.C.

    2000-01-01

    Mars Global Surveyor images, with resolutions as high as 1.5 m pixel, enable characterization of martian channels and valleys at resolutions one to two orders of magnitude better than was previously possible. A major surprise is the near-absence of valleys a few hundred meters wide and narrower. The almost complete absence of fine-scale valleys could be due to lack of precipitation, destruction of small valleys by erosion, or dominance of infiltration over surface runoff. V-shaped valleys with a central channel, such as Nanedi Vallis, provide compelling evidence for sustained or episodic flow of water across the surface. Larger valleys appear to have formed not by headward erosion as a consequence of groundwater sapping but by erosion from water sources upstream of the observed sections. The freshest appearing valleys have triangular cross sections, with talus from opposing walls meeting at the center of the valley. The relations suggest that the width of the valleys is controlled by the depth of incision and the angle of repose of the walls. The flat floors of less fresh-appearing valleys result primarily from later eolian fill. Several discontinuous valleys and lines of craters suggest massive subsurface solution or erosion. The climatic implications of the new images will remain obscure until the cause for the scarcity of fine-scale dissection is better understood. ?? 2000 Academic Press.

  10. Mars Pathfinder Landing Site: Evidence for a Change in Wind Regime and Climate from Lander and Orbiter Data

    NASA Technical Reports Server (NTRS)

    Greeley, R.; Kraft, M. D.; Kuzmin, R. O.; Bridges, N. T.

    1999-01-01

    Surface features related to the wind are observed in data from the Mars Pathfinder lander and from orbit by the Viking Orbiter and Mars Global Surveyor missions. Features seen from the surface include wind tails associated with small rocks, barchanoid duneforms, ripplelike patterns, and ventifact flutes cut into some rocks. Features seen from orbit include wind tails associated with impact craters, ridges inferred to be duneforms, and modified crater rims interpreted to have been eroded and mantled by windblown material. The orientations of these features show two prevailing directions, one inferred to represent winds from the northeast which is consistent with strongest winds predicted by a general circulation model to occur during the Martian northern winter under current conditions, and a second wind pattern oriented approx. 90 degrees to the first. This latter wind could be from the W-NW or from the E-SE and was responsible for cutting the ventifacts and modifying the crater rims. The two wind regimes could reflect a change in climate related to Mars' obliquity or some other, unknown factor. Regardless of the cause, the MPF area has been subjected to a complex pattern of winds and supply of small particles, in which the original surface formed by sedimentary processes from Tiu and Ares Vallis events has been modified by repeated burial and exhumation.

  11. Lunar and Planetary Science XXXVI, Part 15

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Contents include the following: Impact Metamorphism of Subsurface Organic Matter on Mars: A Potential Source for Methane and Surface Alteration. Preliminary Study of Polygonal Impact Craters in Argyre Region, Mars. Geochemistry of the Dark Veinlets in the Granitoids from the Souderfjarden Impact Structure, Finland: Preliminary Results. An Experimental Method to Estimate the Chemical Reaction Rate in Vapor Clouds: An Application to the K/T Impact. Study of the Apollo 16 Landing Site: Re-Visit as a Standard Site for the SELENE Multiband Imager. First X-Ray Observation of Lunar Farside from Hayabusa X-Ray Spectrometer. Lunar X-Ray Fluorescence Spectrometry from SELENE Lunar Polar Orbiter. Origin and Thermal History of Lithic Materials in the Begaa LL3 Chondrite. Evidence of Normal Faulting and Dike Intrusion at Valles Marineris from Pit Crater Topography. Evidence of Tharsis-Radial Dike Intrusion in Southeast Alba Patera from MOLA-based Topography of Pit Crater Chains. Are They Really Intact? Evaluation of Captured Micrometeoroid Analogs by Aerogel at the Flyby Speed of Stardust. Numerical Simulations of Impactor Penetration into Ice-Over-Water Targets. A Probable Fluid Lava Flow in the Hebes Mensa (Mars) Studied by HRSC Images. New Drill-Core Data from the Lockne Crater, Sweden: The Marine Excavation and Ejection Processes, and Post-Impact Environment. Cross-Sectional Profile of Baltis Vallis Channel on Venus: Reconstruction from Magellan SAR Brightness Data.

  12. DOMAIN DECOMPOSITION METHOD APPLIED TO A FLOW PROBLEM Norberto C. Vera Guzmán Institute of Geophysics, UNAM

    NASA Astrophysics Data System (ADS)

    Vera, N. C.; GMMC

    2013-05-01

    In this paper we present the results of macrohybrid mixed Darcian flow in porous media in a general three-dimensional domain. The global problem is solved as a set of local subproblems which are posed using a domain decomposition method. Unknown fields of local problems, velocity and pressure are approximated using mixed finite elements. For this application, a general three-dimensional domain is considered which is discretized using tetrahedra. The discrete domain is decomposed into subdomains and reformulated the original problem as a set of subproblems, communicated through their interfaces. To solve this set of subproblems, we use finite element mixed and parallel computing. The parallelization of a problem using this methodology can, in principle, to fully exploit a computer equipment and also provides results in less time, two very important elements in modeling. Referencias G.Alduncin and N.Vera-Guzmán Parallel proximal-point algorithms for mixed _nite element models of _ow in the subsurface, Commun. Numer. Meth. Engng 2004; 20:83-104 (DOI: 10.1002/cnm.647) Z. Chen, G.Huan and Y. Ma Computational Methods for Multiphase Flows in Porous Media, SIAM, Society for Industrial and Applied Mathematics, Philadelphia, 2006. A. Quarteroni and A. Valli, Numerical Approximation of Partial Differential Equations, Springer-Verlag, Berlin, 1994. Brezzi F, Fortin M. Mixed and Hybrid Finite Element Methods. Springer: New York, 1991.

  13. Potentially dangerous 24-hour rainfall in the Provadiyska vally system at the end of the 20th and early 21st Centuries

    NASA Astrophysics Data System (ADS)

    Vladev, Dimitar

    2018-03-01

    Extreme rainfalls are of paramount importance for the formation of river springs and, consequently, the occurrence of spills and floods. The article presents the results of a case study of the potentially dangerous 24-hour eruptions in the Provadiyska valley system from the end of the 20th and the beginning of the 21st century. Particular attention is paid to the morphometric parameters and the configuration of the river-valley supply network of the Provadiyska river. On this basis, there are defined areas in which there are favorable conditions for forming high river waves.

  14. The Diversity of Martian Volcanic Features as Seen in MOC Images and MOLA Topographic Data

    NASA Technical Reports Server (NTRS)

    Mouginis-Mark, Peter J.

    2004-01-01

    This project focused on the evolution of the summit areas of Martian volcanoes. By using data collected from the Mars Orbiter Camera (MOC) and Mars Laser Altimeter (MOLA) instruments, we tried to better understand the diversity of constructional volcanism on Mars, and hence further understand eruption processes. We investigated the styles of volcanism on the major volcanic constructs (Olympus, Arsia, Pavonis, and Ascraeus Montes), and also studied the role of magma-volatile interactions within the shallow subsurface of these volcanoes and the surrounding areas. Theoretical models for internal processes within volcanoes, including the thermal influences of dike intrusions on pre-existing volatiles, were developed based on our identification of landform distributions. Our work provided new insights into the diversity of volcanism on Mars, and the distribution of Martian volatiles in space and time. Highlights of our results include: 1) The identification of large ash deposits at the summit of Arsia Mons; 2) The study of a large flank eruption on Elysium Mons and the estimation of the effusion rate needed to produce the observed lava channel; 3) The quantitative description of dike intrusion into volatile-rich terrain to explain the origin of Hrad Vallis; 4) The identification of constructional ridges on top of very young lava flows from Olympus Mons, with the interpretation that these ridges were formed by very recent phreatomagmatic eruptions; and 5) The characterization of the dimensions and slope distributions on 18 volcanic edifices on Mars.

  15. Floor of Juventae Chasma

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 30 May 2002) Juventae Chasma is an enormous box canyon (250 km X 100 km) which opens to the north and forms the outflow channel Maja Vallis. Most Martian outflow channels such as Maja, Kasei, and Ares Valles begin at point sources such as box canyons and chaotic terrain and then flow unconfined into a basin region. This image captures a portion of the western floor of Juventae Chasma and shows a wide variety of landforms. Conical hills, mesas, buttes and plateaus of layered material dominate this scene and seem to be 'swimming' in vast sand sheets. The conical hills have a spur and gully topography associated with them while the flat topped buttes and mesas do not. This may be indicative of different materials that compose each of these landforms or it could be that the flat-topped layer has been completely eroded off of the conical hills thereby exposing a different rock type. Both the conical hills and flat-topped buttes and mesas have extensive scree slopes (heaps of eroded rock and debris). Ripples, which are inferred to be dunes, can also be seen amongst the hills. No impact craters can be seen in this image, indicating that the erosion and transport of material down the canyon wall and across the floor is occurring at a relatively rapid rate, so that any craters that form are rapidly buried or eroded.

  16. Catastrophic ice lake collapse in Aram Chaos, Mars

    NASA Astrophysics Data System (ADS)

    Roda, Manuel; Kleinhans, Maarten G.; Zegers, Tanja E.; Oosthoek, Jelmer H. P.

    2014-07-01

    Hesperian chaotic terrains have been recognized as the source of outflow channels formed by catastrophic outflows. Four main scenarios have been proposed for the formation of chaotic terrains that involve different amounts of water and single or multiple outflow events. Here, we test these scenarios with morphological and structural analyses of imagery and elevation data for Aram Chaos in conjunction with numerical modeling of the morphological evolution of the catastrophic carving of the outflow valley. The morphological and geological analyses of Aram Chaos suggest large-scale collapse and subsidence (1500 m) of the entire area, which is consistent with a massive expulsion of liquid water from the subsurface in one single event. The combined observations suggest a complex process starting with the outflow of water from two small channels, followed by continuous groundwater sapping and headward erosion and ending with a catastrophic lake rim collapse and carving of the Aram Valley, which is synchronous with the 2.5 Ga stage of the Ares Vallis formation. The water volume and formative time scale required to carve the Aram channels indicate that a single, rapid (maximum tens of days) and catastrophic (flood volume of 9.3 × 104 km3) event carved the outflow channel. We conclude that a sub-ice lake collapse model can best explain the features of the Aram Chaos Valley system as well as the time scale required for its formation.

  17. Aqueous mineralogy and stratigraphy at and around the proposed Mawrth Vallis MSL Landing Site: New insights into the aqueous history of the region

    USGS Publications Warehouse

    Dobrea, Eldar Z. Noe; Michalski, Joseph; Swayze, Gregg

    2011-01-01

    In this work, we have confirmed the mineralogical stratigraphy previously inferred by other authors, but also demonstrate the presence of additional minerals, including a possible acid-leaching product near the top of the sequence, an Mh-OH bearing phyllosilicate at the to of the sequence, and potentially a Ca-sulfate at the bottom of the phyllosilicate sequence. The latter has important implications regarding the relative timing of sulfate vs clay formation on Mars.

  18. Characterisation of sites of astrobiology interest for Mars landers and sample return missions

    NASA Astrophysics Data System (ADS)

    Wills, D. E. S.; Monaghan, E. P.; Foing, B. H.

    2009-04-01

    priority sites and a safe-haven. The sites chosen are Mawrth Vallis (21.6°N, 344.0°E) and Vernal Crater (5.9°N, 355.3°E), and a safe-haven in Eastern Meridiani (0° N, 3.7°E). The entire length of Mawrth Vallis is of interest, not least because the source is unknown. It doesn't begin in chaotic terrain like the majority of outflow channels. Weathered phyllosilicates are prevalent and their variety, concentration and surface area are currently unmatched compared to anywhere on Mars. They exist in layered outcrops. Structures in Vernal Crater are strongly suggestive of spring deposits, which would have a high potential for preservation of biosignatures. Other key features of interest at this site include probable lake-shore and regional fluvial deposits, lacustrine layers and evidence of methane activity. Eastern Meridiani has been nominated as a potential safe-haven. The science interest of this site includes many diverse layers, evidence of phyllosilicates, and excavation of underlying material by cratering. General references: G. Neukum, R. Jaumann et al., HRSC: The High Resolution Stereo Camera of Mars Express, in Mars Express: The scientific payload, edited by A. Wilson, pp. 17-35, ESA, Noordwijk, The Netherlands, 2004; R. Jaumann, G. Neukum, T. Behnke, T.C. Duxburry, K. Eichentopf, S. van Gasselt, B. Giese, K. Gwinner, E. Hauber, H. Hoffmann, A. Hoffmeister, U. Köhler, K.D; Matz, T.B. McCord, V. Mertens, J. Oberst, R. Pischel, D. Reiß, E. Ress, T. Roatsch, P. Saiger, F. Scholten, G. Schwarz, K. Stephan, M. Wählisch, and the HRSC; Co-Investigator Team: The High Resolution Stereo Camera (HRSC) Experiment on Mars Express: Instrument Aspects and Experiment Conduct from Interplanetary; Cruise through Nominal Mission, Planetary and Space Science, 55, 928-952, 2007.

  19. Relationship Between Topography and the Eastern Equatorial Hydrogen Signal on Mars

    NASA Astrophysics Data System (ADS)

    Clevy, J. R.; Elphic, R. C.; Feldman, W. C.; Kattenhorn, S. A.

    2005-12-01

    Epithermal neutron flux data received from the Neutron Spectrometer, part of the Gamma Ray Spectrometer suite on board NASA's Mars Odyssey, indicates elevated equatorial hydrogen deposits partially encircle the Schiaparelli Basin. Deconvolution of the hydrogen signal statistically increased the resolution over the spectrometer's original 600 km footprint. The resulting map of hydrogen concentrations was further refined by ignoring all data <8.9% Water Equivalent Hydrogen (WEH). In so doing, this study provides the most detailed map to date of the hydrogen concentration maxima in this region and serves as a guide for future exploration. Projecting the Eastern Equatorial Hydrogen map onto the digital elevation model for the Schiaparelli Basin reveals several areas of interest. For simplification, these areas are identified by clock position relative to Schiaparelli. At the twelve o'clock position, a maximum exceeding 10% WEH occupies the upper, northern slope of a saddle between Henry Crater and unnamed craters west of Henry. Viking images of the nameless craters demonstrate wind streaks from the north veer to the southwest here, following topography. Surface drainage channels are apparent on the slope below the local WEH maximum. The 2:30 maximum lies over Tuscaloosa Crater and Verde Vallis. This >10% WEH maximum has the greatest aerial extent, roughly 200 km in diameter. At 5 o'clock, the fringing range adjacent to Brazos Valles lies within the surficially dark region called Sinus Sabaeus. It should be noted that projection of the albedo map over the terrain reveals dark grains concentrating in low areas, presumably having moved short distances by wind and gravity. The absence or presence of these grains does not seem to affect the measured WEH concentration as the signal's local maximum, about 10.2%, crosses areas of high and low albedo without an increase or decrease in signal strength. At 6 o'clock, two 10.4% WEH maxima line the north-facing slope of another

  20. Sands at Gusev Crater, Mars

    NASA Astrophysics Data System (ADS)

    Cabrol, Nathalie A.; Herkenhoff, Kenneth; Knoll, Andrew H.; Farmer, Jack; Arvidson, Raymond; Grin, Edmond; Li, Ronxing; Fenton, Lori; Cohen, Barbara; Bell, James F.; Aileen Yingst, R.

    2014-05-01

    Processes, environments, and the energy associated with the transport and deposition of sand at Gusev Crater are characterized at the microscopic scale through the comparison of statistical moments for particle size and shape distributions. Bivariate and factor analyses define distinct textural groups at 51 sites along the traverse completed by the Spirit rover as it crossed the plains and went into the Columbia Hills. Fine-to-medium sand is ubiquitous in ripples and wind drifts. Most distributions show excess fine material, consistent with a predominance of wind erosion over the last 3.8 billion years. Negative skewness at West Valley is explained by the removal of fine sand during active erosion, or alternatively, by excess accumulation of coarse sand from a local source. The coarse to very coarse sand particles of ripple armors in the basaltic plains have a unique combination of size and shape. Their distribution display significant changes in their statistical moments within the ~400 m that separate the Columbia Memorial Station from Bonneville Crater. Results are consistent with aeolian and/or impact deposition, while the elongated and rounded shape of the grains forming the ripples, as well as their direction of origin, could point to Ma'adim Vallis as a possible source. For smaller particles on the traverse, our findings confirm that aeolian processes have dominated over impact and other processes to produce sands with the observed size and shape patterns across a spectrum of geologic (e.g., ripples and plains soils) and aerographic settings (e.g., wind shadows).

  1. SHARAD soundings and surface roughness at past, present, and proposed landing sites on Mars: Reflections at Phoenix may be attributable to deep ground ice

    NASA Astrophysics Data System (ADS)

    Putzig, Nathaniel E.; Phillips, Roger J.; Campbell, Bruce A.; Mellon, Michael T.; Holt, John W.; Brothers, T. Charles

    2014-08-01

    We use the Shallow Radar (SHARAD) on the Mars Reconnaissance Orbiter to search for subsurface interfaces and characterize surface roughness at the landing sites of Viking Landers 1 and 2, Mars Pathfinder, the Mars Exploration Rovers Spirit and Opportunity, the Phoenix Mars lander, the Mars Science Laboratory Curiosity rover, and three other sites proposed for Curiosity. Only at the Phoenix site do we find clear evidence of subsurface radar returns, mapping out an interface that may be the base of ground ice at depths of ~15-66 m across 2900 km2 in the depression where the lander resides. At the Opportunity, Spirit, and candidate Curiosity sites, images and altimetry show layered materials tens to hundreds of meters thick extending tens to hundreds of kilometers laterally. These scales are well within SHARAD's resolution limits, so the lack of detections is attributable either to low density contrasts in layers of similar composition and internal structure or to signal attenuation within the shallowest layers. At each site, we use the radar return power to estimate surface roughness at scales of 10-100 m, a measure that is important for assessing physical properties, landing safety, and site trafficability. The strongest returns are found at the Opportunity site, indicating that Meridiani Planum is exceptionally smooth. Returns of moderate strength at the Spirit site reflect roughness more typical of Mars. Gale crater, Curiosity's ultimate destination, is the smoothest of the four proposed sites we examined, with Holden crater, Eberswalde crater, and Mawrth Vallis exhibiting progressively greater roughness.

  2. Comparative analysis of fruit aroma patterns in the domesticated wild strawberries “Profumata di Tortona” (F. moschata) and “Regina delle Valli” (F. vesca)

    PubMed Central

    Negri, Alfredo S.; Allegra, Domenico; Simoni, Laura; Rusconi, Fabio; Tonelli, Chiara; Espen, Luca; Galbiati, Massimo

    2015-01-01

    Strawberry is one of the most valued fruit worldwide. Modern cultivated varieties (Fragaria × ananassa) exhibit large fruits, with intense color and prolonged shell life. Yet, these valuable traits were attained at the cost of the intensity and the variety of the aroma of the berry, two characteristics highly appreciated by consumers. Wild species display smaller fruits and reduced yield compared with cultivated varieties but they accumulate broader and augmented blends of volatile compounds. Because of the large diversity and strength of aromas occurring in natural and domesticated populations, plant breeders regard wild strawberries as important donors of novel scented molecules. Here we report a comprehensive metabolic map of the aroma of the wild strawberry Profumata di Tortona (PdT), an ancient clone of F. moschata, considered as one of the most fragrant strawberry types of all. Comparison with the more renowned woodland strawberry Regina delle Valli (RdV), an aromatic cultivar of F. vesca, revealed a significant enrichment in the total level of esters, alcohols and furanones and a reduction in the content of ketones in in the aroma of PdT berries. Among esters, particularly relevant was the enhanced accumulation of methyl anthranilate, responsible for the intensive sweetish impression of wild strawberries. Interestingly, increased ester accumulation in PdT fruits correlated with enhanced expression of the Strawberry Alcohol Acyltransferase (SAAT) gene, a key regulator of flavor biogenesis in ripening berries. We also detected a remarkable 900-fold increase in the level of mesifurane, the furanone conferring the typical caramel notes to most wild species. PMID:25717332

  3. Wind-Driven Erosion and Exposure Potential at Mars 2020 Rover Candidate-Landing Sites.

    PubMed

    Chojnacki, Matthew; Banks, Maria; Urso, Anna

    2018-02-01

    Aeolian processes have likely been the predominant geomorphic agent for most of Mars' history and have the potential to produce relatively young exposure ages for geologic units. Thus, identifying local evidence for aeolian erosion is highly relevant to the selection of landing sites for future missions, such as the Mars 2020 Rover mission that aims to explore astrobiologically relevant ancient environments. Here we investigate wind-driven activity at eight Mars 2020 candidate-landing sites to constrain erosion potential at these locations. To demonstrate our methods, we found that contemporary dune-derived abrasion rates were in agreement with rover-derived exhumation rates at Gale crater and could be employed elsewhere. The Holden crater candidate site was interpreted to have low contemporary erosion rates, based on the presence of a thick sand coverage of static ripples. Active ripples at the Eberswalde and southwest Melas sites may account for local erosion and the dearth of small craters. Moderate-flux regional dunes near Mawrth Vallis were deemed unrepresentative of the candidate site, which is interpreted to currently be experiencing low levels of erosion. The Nili Fossae site displayed the most unambiguous evidence for local sand transport and erosion, likely yielding relatively young exposure ages. The downselected Jezero crater and northeast Syrtis sites had high-flux neighboring dunes and exhibited substantial evidence for sediment pathways across their ellipses. Both sites had relatively high estimated abrasion rates, which would yield young exposure ages. The downselected Columbia Hills site lacked evidence for sand movement, and contemporary local erosion rates are estimated to be relatively low.

  4. Old Crater

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    The large crater in the center of this image is older than all the smaller craters in the rest of the VIS image. The crater no longer has any visible rim or ejecta, and is simply a circular smooth floored basin. The interior has been further modified by both impact and the process that formed the darker markings. This image is from the region near Naktong Vallis.

    Image information: VIS instrument. Latitude -1, Longitude 30.7 East (329.3 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  5. Wind-Driven Erosion and Exposure Potential at Mars 2020 Rover Candidate-Landing Sites

    PubMed Central

    Chojnacki, Matthew; Banks, Maria; Urso, Anna

    2018-01-01

    Aeolian processes have likely been the predominant geomorphic agent for most of Mars’ history and have the potential to produce relatively young exposure ages for geologic units. Thus, identifying local evidence for aeolian erosion is highly relevant to the selection of landing sites for future missions, such as the Mars 2020 Rover mission that aims to explore astrobiologically relevant ancient environments. Here we investigate wind-driven activity at eight Mars 2020 candidate-landing sites to constrain erosion potential at these locations. To demonstrate our methods, we found that contemporary dune-derived abrasion rates were in agreement with rover-derived exhumation rates at Gale crater and could be employed elsewhere. The Holden crater candidate site was interpreted to have low contemporary erosion rates, based on the presence of a thick sand coverage of static ripples. Active ripples at the Eberswalde and southwest Melas sites may account for local erosion and the dearth of small craters. Moderate-flux regional dunes near Mawrth Vallis were deemed unrepresentative of the candidate site, which is interpreted to currently be experiencing low levels of erosion. The Nili Fossae site displayed the most unambiguous evidence for local sand transport and erosion, likely yielding relatively young exposure ages. The downselected Jezero crater and northeast Syrtis sites had high-flux neighboring dunes and exhibited substantial evidence for sediment pathways across their ellipses. Both sites had relatively high estimated abrasion rates, which would yield young exposure ages. The downselected Columbia Hills site lacked evidence for sand movement, and contemporary local erosion rates are estimated to be relatively low. PMID:29568719

  6. Aqueous history of Mars as inferred from landed mission measurements of rocks, soils, and water ice

    NASA Astrophysics Data System (ADS)

    Arvidson, Raymond E.

    2016-09-01

    The missions that have operated on the surface of Mars acquired data that complement observations acquired from orbit and provide information that would not have been acquired without surface measurements. Data from the Viking Landers demonstrated that soils have basaltic compositions, containing minor amounts of salts and one or more strong oxidants. Pathfinder with its rover confirmed that the distal portion of Ares Vallis is the site of flood-deposited boulders. Spirit found evidence for hydrothermal deposits surrounding the Home Plate volcanoclastic feature. Opportunity discovered that the hematite signature on Meridiani Planum as seen from orbit is due to hematitic concretions concentrated on the surface as winds eroded sulfate-rich sandstones that dominate the Burns formation. The sandstones originated as playa muds that were subsequently reworked by wind and rising groundwater. Opportunity also found evidence on the rim of the Noachian Endurance Crater for smectites, with extensive leaching along fractures. Curiosity acquired data at the base of Mount Sharp in Gale Crater that allows reconstruction of a sustained fluvial-deltaic-lacustrine system prograding into the crater. Smectites and low concentrations of chlorinated hydrocarbons have been identified in the lacustrine deposits. Phoenix, landing above the Arctic Circle, found icy soils, along with low concentrations of perchlorate salt. Perchlorate is considered to be a strong candidate for the oxidant found by the Viking Landers. It is also a freezing point depressant and may play a role in allowing brines to exist at and beneath the surface in more modern periods of time on Mars.

  7. Canyon formation constraints on the discharge of catastrophic outburst floods of Earth and Mars

    NASA Astrophysics Data System (ADS)

    Lapotre, Mathieu G. A.; Lamb, Michael P.; Williams, Rebecca M. E.

    2016-07-01

    Catastrophic outburst floods carved amphitheater-headed canyons on Earth and Mars, and the steep headwalls of these canyons suggest that some formed by upstream headwall propagation through waterfall erosion processes. Because topography evolves in concert with water flow during canyon erosion, we suggest that bedrock canyon morphology preserves hydraulic information about canyon-forming floods. In particular, we propose that for a canyon to form with a roughly uniform width by upstream headwall retreat, erosion must occur around the canyon head, but not along the sidewalls, such that canyon width is related to flood discharge. We develop a new theory for bedrock canyon formation by megafloods based on flow convergence of large outburst floods toward a horseshoe-shaped waterfall. The model is developed for waterfall erosion by rock toppling, a candidate erosion mechanism in well fractured rock, like columnar basalt. We apply the model to 14 terrestrial (Channeled Scablands, Washington; Snake River Plain, Idaho; and Ásbyrgi canyon, Iceland) and nine Martian (near Ares Vallis and Echus Chasma) bedrock canyons and show that predicted flood discharges are nearly 3 orders of magnitude less than previously estimated, and predicted flood durations are longer than previously estimated, from less than a day to a few months. Results also show a positive correlation between flood discharge per unit width and canyon width, which supports our hypothesis that canyon width is set in part by flood discharge. Despite lower discharges than previously estimated, the flood volumes remain large enough for individual outburst floods to have perturbed the global hydrology of Mars.

  8. Sands at Gusev Crater, Mars

    USGS Publications Warehouse

    Cabrol, Nathalie A.; Herkenhoff, Kenneth E.; Knoll, Andrew H.; Farmer, Jack D.; Arvidson, Raymond E.; Grin, E.A.; Li, Ron; Fenton, Lori; Cohen, B.; Bell, J.F.; Yingst, R. Aileen

    2014-01-01

    Processes, environments, and the energy associated with the transport and deposition of sand at Gusev Crater are characterized at the microscopic scale through the comparison of statistical moments for particle size and shape distributions. Bivariate and factor analyses define distinct textural groups at 51 sites along the traverse completed by the Spirit rover as it crossed the plains and went into the Columbia Hills. Fine-to-medium sand is ubiquitous in ripples and wind drifts. Most distributions show excess fine material, consistent with a predominance of wind erosion over the last 3.8 billion years. Negative skewness at West Valley is explained by the removal of fine sand during active erosion, or alternatively, by excess accumulation of coarse sand from a local source. The coarse to very coarse sand particles of ripple armors in the basaltic plains have a unique combination of size and shape. Their distribution display significant changes in their statistical moments within the ~400 m that separate the Columbia Memorial Station from Bonneville Crater. Results are consistent with aeolian and/or impact deposition, while the elongated and rounded shape of the grains forming the ripples, as well as their direction of origin, could point to Ma'adim Vallis as a possible source. For smaller particles on the traverse, our findings confirm that aeolian processes have dominated over impact and other processes to produce sands with the observed size and shape patterns across a spectrum of geologic (e.g., ripples and plains soils) and aerographic settings (e.g., wind shadows).

  9. Wind-Driven Erosion and Exposure Potential at Mars 2020 Rover Candidate-Landing Sites

    NASA Astrophysics Data System (ADS)

    Chojnacki, Matthew; Banks, Maria; Urso, Anna

    2018-02-01

    Aeolian processes have likely been the predominant geomorphic agent for most of Mars' history and have the potential to produce relatively young exposure ages for geologic units. Thus, identifying local evidence for aeolian erosion is highly relevant to the selection of landing sites for future missions, such as the Mars 2020 Rover mission that aims to explore astrobiologically relevant ancient environments. Here we investigate wind-driven activity at eight Mars 2020 candidate-landing sites to constrain erosion potential at these locations. To demonstrate our methods, we found that contemporary dune-derived abrasion rates were in agreement with rover-derived exhumation rates at Gale crater and could be employed elsewhere. The Holden crater candidate site was interpreted to have low contemporary erosion rates, based on the presence of a thick sand coverage of static ripples. Active ripples at the Eberswalde and southwest Melas sites may account for local erosion and the dearth of small craters. Moderate-flux regional dunes near Mawrth Vallis were deemed unrepresentative of the candidate site, which is interpreted to currently be experiencing low levels of erosion. The Nili Fossae site displayed the most unambiguous evidence for local sand transport and erosion, likely yielding relatively young exposure ages. The downselected Jezero crater and northeast Syrtis sites had high-flux neighboring dunes and exhibited substantial evidence for sediment pathways across their ellipses. Both sites had relatively high estimated abrasion rates, which would yield young exposure ages. The downselected Columbia Hills site lacked evidence for sand movement, and contemporary local erosion rates are estimated to be relatively low.

  10. Detailed mapping of surface units on Mars with HRSC color data

    NASA Astrophysics Data System (ADS)

    Combe, J.-Ph.; Wendt, L.; McCord, T. B.; Neukum, G.

    2008-09-01

    at Aram Chaos or Terra Meridiani [7-9] is a candidate. Bright deposits have potentially spectral signatures different to the red dust in the visible: sulfates in Juventae Chasma or Aram Chaos [9, 10] and phyllosilicates in Mawrth Vallis [11] or Nili Fossae [12] are of interest. This abstract is focused on Marwth Vallis only. HRSC spectral data: geometry and color filters The spectral data are image mosaics of five broadband spectral channels centered respectively at 440, 530, 650 and 750 nm for covering the visible range of wavelengths and 970 nm for sensitivity to the electronic absorptions of minerals present in minerals (pyroxenes, olivine). The third channel (nadir image) has a typical pixel size of 12.5 m, 25 m or 50 m. The other channels have a usual pixel size of 50 m, 100 m or 200 m that determines the spatial sampling of the spectral dataset. These data are acquired by five individual cameras oriented with a specific angle to the normal to the surface (-3°, +3°, 0° (nadir), -16° and +16° respectively). Those tilts optimize the use of a single telescope for all cameras in the available room. Thus, a given spectrum results from different proportions of shade at each wavelength. Indeed, subpixel topographic slopes that are oriented toward the instrument represent a higher proportion in the signal. This implies that shade affects the shape of HRSC spectra on a different way from pixel to pixel. This contribution has to be considered when performing spectral analysis. Level-4 color images in Digital Numbers (DNs) are registered adequately and are available to the public through the HRSCview website (http://hrscview.fu-berlin.de). A linear function converts the DNs into radiance factor (I/F). Visual interpretation Color composites Red-Green-blue (RGB) color composites of DNs images contain usable geological information. Dark basaltic sands and bright red dust appear always obvious. Materials generated from interaction of liquid water, like sulfates and

  11. Predictability of Sleep in Patients with Insomnia

    PubMed Central

    Vallières, Annie; Ivers, Hans; Beaulieu-Bonneau, Simon; Morin, Charles M.

    2011-01-01

    Study Objectives: To evaluate whether the night-to-night variability in insomnia follows specific predictable patterns and to characterize sleep patterns using objective sleep and clinical variables. Design: Prospective observational study. Setting: University-affiliated sleep disorders center. Participants: 146 participants suffering from chronic and primary insomnia. Measurements and Results: Daily sleep diaries were completed for an average of 48 days and self-reported questionnaires once. Three nights were spent in the sleep laboratory for polysomnographic (PSG) assessment. Sleep efficiency, sleep onset latency, wake after sleep onset, and total sleep time were derived from sleep diaries and PSG. Time-series diary data were used to compute conditional probabilities of having an insomnia night after 1, 2, or 3 consecutive insomnia night(s). Conditional probabilities were submitted to a k-means cluster analysis. A 3-cluster solution was retained. One cluster included 38 participants exhibiting an unpredictable insomnia pattern. Another included 30 participants with a low and decreasing probability to have an insomnia night. The last cluster included 49 participants exhibiting a high probability to have insomnia every night. Clusters differed on age, insomnia severity, and mental fatigue, and on subjective sleep variables, but not on PSG sleep variables. Conclusion: These findings replicate our previous study and provide additional evidence that unpredictability is a less prevalent feature of insomnia than suggested previously in the literature. The presence of the 3 clusters is discussed in term of sleep perception and sleep homeostasis dysregulation. Citation: Vallières A; Ivers H; Beaulieu-Bonneau S; Morin CM. Predictability of sleep in patients with insomnia. SLEEP 2011;34(5):609-617. PMID:21532954

  12. Ancient Streamlined Islands of the Palos Outflow Channel

    NASA Image and Video Library

    2016-08-24

    This image shows the northern terminus of an outflow channel located in the volcanic terrains of Amenthes Planum. The channel sources from the Palos impact crater to the south, where water flowed into the crater from Tinto Vallis and eventually formed a paleo lake. As rising lake levels breached through the crater's rim and inundated the plains to the north, the resulting high velocity, large discharge floods plucked out and eroded the volcanic plains scouring out the "Palos Outflow Channel" and the streamlined mesa-islands on its floor. These streamlined forms are the eroded remnants of plains material sculpted by catastrophic floods and are not sediment deposits emplaced by lower magnitude stream flows. Both the fluvial channel floor and the volcanic island surfaces are densely cratered by impacts suggesting that both the surfaces and the flood events are ancient. The morphology (shape) of the channel system and its islands have been preserved through the eons, but water has long been absent from this drainage system. Since then, winds have transported light-toned sediments across this terrain forming extensive dune fields within the channel system, on the floors of impact craters, and in other protected locations in the Palos Outflow Channel region. A closer look shows chevron, or fish-bone shaped, light-toned dunes located near the top of the image where numerous smaller channels have cut through the landscape. These dunes likely started out as Transverse Aeolian Ridges (TAR) that form perpendicular to the prevailing wind direction where the wind-blown sediment supply is scarce. This intriguing morphology likely reflects changes in the prevailing wind environment over time. http://photojournal.jpl.nasa.gov/catalog/PIA21023

  13. Regional Topographic Views of Mars from MOLA

    NASA Technical Reports Server (NTRS)

    2000-01-01

    With one year of global mapping of the Mars Global Surveyor mission completed, the MOLA dataset has achieved excellent spatial and vertical resolution. The maps below (and above) have been produced from the altimetric observations collected during MOLA's first year of global mapping and provide a variety of regional topographic views of the Martian surface. The maps were compiled from a data base of 266.7 million laser altimetric measurements collected between March 1, 1999 and February 29, 2000. In each map the spatial resolution is approximately 1/16o by 1/32o (where 1o on Mars is about 59 km) and the vertical accuracy is approximately 1 meter. Note that the sizes of the regions vary. Click on image for to see full resolution (Warning! these are large files) [figure removed for brevity, see original site] Nirgal Vallis region: 23o to 33o S; 313 to 323o E.

    [figure removed for brevity, see original site] Locras Valles region: 5o to 15o N; 45 to 55o E.

    [figure removed for brevity, see original site] Syrtis Major: 5o to 15o S; 62 to 72o E.

    [figure removed for brevity, see original site] Viking 1 landing site: 20o to 25o N; 310 to 315o E. The landing site is marked by the plus sign.

    [figure removed for brevity, see original site] Nicholson crater: 5o S to 5o N; 190 to 200o E. [figure removed for brevity, see original site] Schiaparelli crater: 8o S to 2o N; 12 to 22o E.

  14. Palos Crater

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    Palos Crater has been suggested as a future landing site for Mars Missions. This crater has a channel called Tinto Vallis, which enters from the south. This site was suggested as a landing site because it may contain lake deposits. Palos Crater is named in honor of the port city in Spain from which Christopher Columbus sailed on his way to the New World in August of 1492. The floor of Palos Crater appears to be layered in places providing further evidence that this site may in fact have been the location of an ancient lake.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  15. Digital mapping of the Mars Pathfinder landing site: Design, acquisition, and derivation of cartographic products for science applications

    USGS Publications Warehouse

    Gaddis, L.R.; Kirk, R.L.; Johnson, J. R.; Soderblom, L.A.; Ward, A.W.; Barrett, J.; Becker, K.; Decker, T.; Blue, J.; Cook, D.; Eliason, E.; Hare, T.; Howington-Kraus, E.; Isbell, C.; Lee, E.M.; Redding, B.; Sucharski, R.; Sucharski, T.; Smith, P.H.; Britt, D.T.

    1999-01-01

    The Imager for Mars Pathfinder (IMP) acquired more than 16,000 images and provided panoramic views of the surface of Mars at the Mars Pathfinder landing site in Ares Vallis. This paper describes the stereoscopic, multispectral IMP imaging sequences and focuses on their use for digital mapping of the landing site and for deriving cartographic products to support science applications of these data. Two-dimensional cartographic processing of IMP data, as performed via techniques and specialized software developed for ISIS (the U.S.Geological Survey image processing software package), is emphasized. Cartographic processing of IMP data includes ingestion, radiometric correction, establishment of geometric control, coregistration of multiple bands, reprojection, and mosaicking. Photogrammetric processing, an integral part of this cartographic work which utilizes the three-dimensional character of the IMP data, supplements standard processing with geometric control and topographic information [Kirk et al., this issue]. Both cartographic and photogrammetric processing are required for producing seamless image mosaics and for coregistering the multispectral IMP data. Final, controlled IMP cartographic products include spectral cubes, panoramic (360?? azimuthal coverage) and planimetric (top view) maps, and topographic data, to be archived on four CD-ROM volumes. Uncontrolled and semicontrolled versions of these products were used to support geologic characterization of the landing site during the nominal and extended missions. Controlled products have allowed determination of the topography of the landing site and environs out to ???60 m, and these data have been used to unravel the history of large- and small-scale geologic processes which shaped the observed landing site. We conclude by summarizing several lessons learned from cartographic processing of IMP data. Copyright 1999 by the American Geophysical Union.

  16. Screening of soy protein-derived hypotriglyceridemic di-peptides in vitro and in vivo

    PubMed Central

    2011-01-01

    Background Soy protein and soy peptides have attracted considerable attention because of their potentially beneficial biological properties, including antihypertensive, anticarcinogenic, and hypolipidemic effects. Although soy protein isolate contains several bioactive peptides that have distinct physiological activities in lipid metabolism, it is not clear which peptide sequences are responsible for the triglyceride (TG)-lowering effects. In the present study, we investigated the effects of soy protein-derived peptides on lipid metabolism, especially TG metabolism, in HepG2 cells and obese Otsuka Long-Evans Tokushima fatty (OLETF) rats. Results In the first experiment, we found that soy crude peptide (SCP)-LD3, which was prepared by hydrolyze of soy protein isolate with endo-type protease, showed hypolipidemic effects in HepG2 cells and OLETF rats. In the second experiment, we found that hydrophilic fraction, separated from SCP-LD3 with hydrophobic synthetic absorbent, revealed lipid-lowering effects in HepG2 cells and OLETF rats. In the third experiment, we found that Fraction-C (Frc-C) peptides, fractionated from hydrophilic peptides by gel permeation chromatography-high performance liquid chromatography, significantly reduced TG synthesis and apolipoprotein B (apoB) secretion in HepG2 cells. In the fourth experiment, we found that the fraction with 0.1% trifluoroacetic acid, isolated from Frc-C peptides by octadecylsilyl column chromatography, showed hypolipidemic effects in HepG2 cells. In the final experiment, we found that 3 di-peptides, Lys-Ala, Val-Lys, and Ser-Tyr, reduced TG synthesis, and Ser-Tyr additionally reduced apoB secretion in HepG2 cells. Conclusion Novel active peptides with TG-lowering effects from soy protein have been isolated. PMID:21600040

  17. The Keck "Mars 2000" Project: Using Mars Orbiter Laser Altimeter Data to Assess Geological Processes and Regional Stratigraphy Near Orcus Patera and Marte Vallis on Mars

    NASA Technical Reports Server (NTRS)

    Grosfils, E. B.; Sakimoto, S. E. H.; Mendelson, C. V.; Bleacher, J. E.

    2001-01-01

    During the Keck 'Mars 2000' summer project 10 undergraduates (rising juniors) used Mars Orbiter Laser Altimeter (MOLA) data to study a 19x14 degree region they identified as a potential Mars 2003 landing site. Here we introduce the project science and organization. Additional information is contained in the original extended abstract.

  18. Indicators and Methods to Understand Past Environments from ExoMars Rover Drills

    NASA Astrophysics Data System (ADS)

    Kereszturi, A.; Bradak, B.; Chatzitheodoridis, E.; Ujvari, G.

    2016-11-01

    Great advances are expected during the analysis of drilled material acquired from 2 m depth by ExoMars rover, supported by the comparison to local context, and the joint use of different instruments. Textural information might be less detailed relatively to what is usually obtained at outcrops during classical geological field work on the Earth, partly because of the lack of optical imaging of the borehole wall and also because the collected samples are crushed. However sub-mm scale layering and some other sedimentary features might be identified in the borehole wall observations, or in the collected sample prior to crushing, and also at nearby outcrops. The candidate landing sites provide different targets and focus for research: Oxia Planum requires analysis of phyllosilicates and OH content, at Mawrth Vallis the layering of various phyllosilicates and the role of shallow-subsurface leaching should be emphasized. At Aram Dorsum the particle size and fluvial sedimentary features will be interesting. Hydrated perchlorates and sulphates are ideal targets possibly at every landing sites because of OH retention, especially if they are mixed with smectites, thus could point to even ancient wet periods. Extensive use of information from the infrared wall scanning will be complemented for geological context by orbital and rover imaging of nearby outcrops. Information from the context is especially useful to infer the possible action of past H2O. Separation of the ice and liquid water effects will be supported by cation abundance and sedimentary context. Shape of grains also helps here, and composition of transported grains points to the weathering potential of the environment in general. The work on Mars during the drilling and sample analysis will provide brand new experience and knowledge for future missions.

  19. A Case for Hydrothermal Gray Hematite in Aram Chaos

    NASA Technical Reports Server (NTRS)

    Catling, D. C.; Moore, J. M.

    2003-01-01

    The Thermal Emission Spectrometer (TES) on Mars Global Surveyor has detected deposits of coarsegrained, gray crystalline hematite in Sinus Meridiani, Aram Chaos, and Vallis Marineris [1]. Detailed features in the hematite spectral signature of the Sinus Meridiani region show that the spectrum is consistent with emission dominated by crystal c-faces of hematite, implying that the hematite is specular [2]. Gray specular hematite (also known as specularite ) is a particular gray crystalline form that has intergrown, hexagonal plates with a silvery metallic luster. We believe that the key to the origin of specularite is that it requires crystallization at temperatures in excess of about 100 C. In reviewing the occurrence of gray hematite on Earth, we find no exceptions to this warm temperature requirement [3]. Thermal crystallization on Mars could occur (1) as diagenesis at a depth of a few kilometers of sediments originally formed in lowtemperature waters, or (2) as direct precipitation from hydrothermal solution. Aram Chaos has unique chaotic terrain that offers more clues to the formation of the hematite than the relatively featureless flat terrain (as seen from orbit) of Sinus Meridiani. Aram Chaos provides the opportunity to look at a combination of TES data, Mars Orbiter Camera images, and Mars Orbiter Laser Altimeter (MOLA) topography. This combination of data suggests that high concentrations of hematite were formed in planar strata and have since been exposed by erosion of an overlying light-toned, caprock. Lesser concentrations of hematite are found adjacent to these strata at lower elevations, which we interpret as perhaps a lag deposit. The topography and the collapsed nature of the chaotic terrain favor a hydrothermally charged aquifer as the original setting where the hematite formed. An alternative sedimentary origin requires post-depositional burial to a depth of 3-5 km to induce thermally driven recrystallization of fine-grained iron oxides to coarse

  20. Automatic classification of spectral units in the Aristarchus plateau

    NASA Astrophysics Data System (ADS)

    Erard, S.; Le Mouelic, S.; Langevin, Y.

    1999-09-01

    A reduction scheme has been recently proposed for the NIR images of Clementine (Le Mouelic et al, JGR 1999). This reduction has been used to build an integrated UVvis-NIR image cube of the Aristarchus region, from which compositional and maturity variations can be studied (Pinet et al, LPSC 1999). We will present an analysis of this image cube, providing a classification in spectral types and spectral units. The image cube is processed with Gmode analysis using three different data sets: Normalized spectra provide a classification based mainly on spectral slope variations (ie. maturity and volcanic glasses). This analysis discriminates between craters plus ejecta, mare basalts, and DMD. Olivine-rich areas and Aristarchus central peak are also recognized. Continuum-removed spectra provide a classification more related to compositional variations, which correctly identifies olivine and pyroxenes-rich areas (in Aristarchus, Krieger, Schiaparelli\\ldots). A third analysis uses spectral parameters related to maturity and Fe composition (reflectance, 1 mu m band depth, and spectral slope) rather than intensities. It provides the most spatially consistent picture, but fails in detecting Vallis Schroeteri and DMDs. A supplementary unit, younger and rich in pyroxene, is found on Aristarchus south rim. In conclusion, Gmode analysis can discriminate between different spectral types already identified with more classic methods (PCA, linear mixing\\ldots). No previous assumption is made on the data structure, such as endmembers number and nature, or linear relationship between input variables. The variability of the spectral types is intrinsically accounted for, so that the level of analysis is always restricted to meaningful limits. A complete classification should integrate several analyses based on different sets of parameters. Gmode is therefore a powerful light toll to perform first look analysis of spectral imaging data. This research has been partly founded by the French

  1. Nightmares: Risk Factors Among the Finnish General Adult Population

    PubMed Central

    Sandman, Nils; Valli, Katja; Kronholm, Erkki; Revonsuo, Antti; Laatikainen, Tiina; Paunio, Tiina

    2015-01-01

    Study Objectives: To identify risk factors for experiencing nightmares among the Finnish general adult population. The study aimed to both test whether previously reported correlates of frequent nightmares could be reproduced in a large population sample and to explore previously unreported associations. Design: Two independent cross-sectional population surveys of the National FINRISK Study. Setting: Age- and sex-stratified random samples of the Finnish population in 2007 and 2012. Participants: A total of 13,922 participants (6,515 men and 7,407 women) aged 25–74 y. Interventions: N/A. Measurements and results: Nightmare frequency as well as several items related to socioeconomic status, sleep, mental well-being, life satisfaction, alcohol use, medication, and physical well-being were recorded with a questionnaire. In multinomial logistic regression analysis, a depression-related negative attitude toward the self (odds ratio [OR] 1.32 per 1-point increase), insomnia (OR 6.90), and exhaustion and fatigue (OR 6.86) were the strongest risk factors for experiencing frequent nightmares (P < 0.001 for all). Sex, age, a self-reported impaired ability to work, low life satisfaction, the use of antidepressants or hypnotics, and frequent heavy use of alcohol were also strongly associated with frequent nightmares (P < 0.001 for all). Conclusions: Symptoms of depression and insomnia were the strongest predictors of frequent nightmares in this dataset. Additionally, a wide variety of factors related to psychological and physical well-being were associated with nightmare frequency with modest effect sizes. Hence, nightmare frequency appears to have a strong connection with sleep and mood problems, but is also associated with a variety of measures of psychological and physical well-being. Citation: Sandman N, Valli K, Kronholm E, Revonsuo A, Laatikainen T, Paunio T. Nightmares: risk factors among the finnish general adult population. SLEEP 2015;38(4):507–514. PMID:25325474

  2. Ancient deltas on Mars: outstanding targets for martian habitability?

    NASA Astrophysics Data System (ADS)

    Gupta, S.; Fawdon, P.; Grindrod, P. M.; Balme, M. R.; Hauber, E.; Warner, N. H.; Muller, J. P.

    2014-12-01

    The identification of putative ancient deltaic sedimentary systems on Mars has been both exciting and controversial. Our excitement is elicted by the potential provided by deltas as evidence for standing bodies of water associated with the deltas, and the resulting implications for both the ancient climate of Mars and ancient habitability. The controversy stems from how confident can we be in the identification of ancient deltaic systems from orbital data, and how robust are our assertions about the habitability potential of such settings. Delta systems in particular are key astrobiological targets because at their distal toes fine-grained sediment (ie., clays) settle from suspension in a lower energy setting and they are commonly characterised by high rates of sedimentation. This leads to high preservation potential of biosignatures. Targeting of future Mars rovers to investigate deltaic landing sites requires better understanding of these issues to reduce exploration risk. In this presentation, we describe the key criteria that enable us to make robust interpretations of deltaic stratigraphy and constrain delta evolution for martian systems. In particular, the past 10 years has seen in a revolution in our process understanding of terrestrial delta systems through a combination of field, experimental and numerical modelling studies. Analysis of martian deltas has much to gain from these results. We go on to consider why deltaic systems offer potential as astrobiological target paleoenvironments. We use the exhumed delta system (Hypanis delta system) at the termination of Hypanis Vallis, 11.8°N, 314.96°E as a case example. This system, situated in Xanthe Terra, comprises layered sedimentary rocks with an overall multi-lobate geometry and associated inverted channel networks. The Hypanis 'delta' is a proposed landing site for the ExoMars rover and also for the NASA 2020 mission.

  3. Indicators and Methods to Understand Past Environments from ExoMars Rover Drills.

    PubMed

    Kereszturi, A; Bradak, B; Chatzitheodoridis, E; Ujvari, G

    2016-11-01

    Great advances are expected during the analysis of drilled material acquired from 2 m depth by ExoMars rover, supported by the comparison to local context, and the joint use of different instruments. Textural information might be less detailed relatively to what is usually obtained at outcrops during classical geological field work on the Earth, partly because of the lack of optical imaging of the borehole wall and also because the collected samples are crushed. However sub-mm scale layering and some other sedimentary features might be identified in the borehole wall observations, or in the collected sample prior to crushing, and also at nearby outcrops. The candidate landing sites provide different targets and focus for research: Oxia Planum requires analysis of phyllosilicates and OH content, at Mawrth Vallis the layering of various phyllosilicates and the role of shallow-subsurface leaching should be emphasized. At Aram Dorsum the particle size and fluvial sedimentary features will be interesting. Hydrated perchlorates and sulphates are ideal targets possibly at every landing sites because of OH retention, especially if they are mixed with smectites, thus could point to even ancient wet periods. Extensive use of information from the infrared wall scanning will be complemented for geological context by orbital and rover imaging of nearby outcrops. Information from the context is especially useful to infer the possible action of past H 2 O. Separation of the ice and liquid water effects will be supported by cation abundance and sedimentary context. Shape of grains also helps here, and composition of transported grains points to the weathering potential of the environment in general. The work on Mars during the drilling and sample analysis will provide brand new experience and knowledge for future missions.

  4. Lunar and Planetary Science XXXV: Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The session "Mars" included the following reports:Tentative Theories for the Long-Term Geological and Hydrological Evolution of Mars; Stratigraphy of Special Layers Transient Ones on Permeable Ones: Examples from Earth and Mars; Spatial Analysis of Rootless Cone Groups on Iceland and Mars; Summer Season Variability of the North Residual Cap of Mars from MGS-TES; Spectral and Geochemical Characteristics of Lake Superior Type Banded Iron Formation: Analog to the Martian Hematite Outcrops; Martian Wave Structures and Their Relation to Mars; Shape, Highland-Lowland Chemical Dichotomy and Undulating Atmosphere Causing Serious Problems to Landing Spacecrafts; Shear Deformation in the Graben Systems of Sirenum Fosssae, Mars: Preliminary Results; Components of Martian Dust Finding on Terrestrial Sedimentary Deposits with Use of Infrared Spectra; Morphologic and Morphometric Analyses of Fluvial Systems in the Southern Highlands of Mars; Light Pattern and Intensity Analysis of Gray Spots Surrounding Polar Dunes on Mars; The Volume of Possible Ancient Oceanic Basins in the Northern Plains of Mars MARSES: Possibilities of Long-Term Monitoring Spatial and Temporal Variations and Changes of Subsurface Geoelectrical Section on the Base; Results of the Geophysical Survey Salt/Water Interface and Groundwater Mapping on the Marina Di Ragusa, Sicily and Shalter Island, USA ;A Miniature UV-VIS Spectrometer for the Surface of Mars; Automatic Recognition of Aeolian Ripples on Mars; Absolute Dune Ages and Implications for the Time of Formation of Gullies in Nirgal Vallis, Mars; Diurnal Dust Devil Behaviour for the Viking 1 Landing Site: Sols 1 to 30; Topography Based Surface Age Computations for Mars: A Step Toward the Formal Proof of Martian Ocean Recession, Timing and Probability; Gravitational Effects of Flooding and Filling of Impact Basins on Mars; Viking 2 Landing Site in MGS/MOC Images South Polar Residual Cap of Mars: Features, Stratigraphy, and Changes.

  5. An experimental flow-through assessment of acidic Fe/Mg smectite formation on early Mars

    NASA Astrophysics Data System (ADS)

    Sutter, B.; Peretyazhko, T.; Garcia, A. H.; Ming, D. W.

    2017-12-01

    Orbital observations have detected the phyllosilicate smectite in layered material hundreds of meters thick, intracrater depositional fans, and plains sediments on Mars; however, the detection of carbonate deposits is limited. Instead of neutral/alkaline conditions during the Noachian, early Mars may have experienced mildly acidic conditions derived from volcanic acid-sulfate solutions that allowed Fe/Mg smectite formation but prevented widespread carbonate formation. The detection of acid sulfates (e.g., jarosite) associated with smectite in Mawrth Vallis supports this hypothesis. Previous work demonstrated smectite (saponite) formation in closed hydrologic systems (batch reactor) from basaltic glass at pH 4 and 200°C (Peretyazhko et al., 2016 GCA). This work presents results from alteration of basaltic glass from alkaline to acidic conditions in open hydrologic systems (flow-through reactor). Preliminary experiments exposed basaltic glass to deionized water at 190°C at 0.25 ml/min where solution pH equilibrated to 9.5. These initial high pH experiments were conducted to evaluate the flow-through reactor system before working with lower pHs. Smectite at this pH was not produced and instead X-ray diffraction results consistent with serpentine was detected. Experiments are in progress exposing basaltic glass from pH 8 down to pH 3 to determine what range of pHs could allow for smectite formation in this experimental open-system. The production of smectite under an experimental open-system at low pHs if successful, would support a significant paradigm shift regarding the geochemical evolution of early Mars: Early Mars geochemical solutions were mildly acidic, not neutral/alkaline. This could have profound implications regarding early martain microbiology where acid conditions instead of neutral/alkaline conditions will require further research in terrestrial analogs to address the potential for biosignature preservation on Mars (Johnson et al., 2016, LPSC).

  6. Primary centers and secondary concentrations of tectonic activity through time in the western hemisphere of Mars

    USGS Publications Warehouse

    Anderson, R.C.; Dohm, J.M.; Golombek, M.P.; Haldemann, A.F.C.; Franklin, B.J.; Tanaka, K.L.; Lias, J.; Peer, B.

    2001-01-01

    Five main stages of radial and concentric structures formed around Tharsis from the Noachian through the Amazonian as determined by geologic mapping of 24,452 structures within the stratigraphic framework of Mars and by testing their radial and concentric orientations. Tectonic activity peaked in the Noachian (stage 1) around the largest center, Claritas, an elongate center extending more than 20?? in latitude and defined by about half of the total grabens which are concentrated in the Syria Planum, Thaumasia, and Tempe Terra regions. During the Late Noachian and Early Hesperian (stage 2), extensional structures formed along the length of present-day Valles Marineris and in Thaumasia (with a secondary concentration near Warrego Vallis) radial to a region just to the south of the central margin of Valles Marineris. Early Hesperian (stage 3) radial grabens in Pavonis, Syria, Ulysses, and Tempe Terra and somewhat concentric wrinkle ridges in Lunae and Solis Plana and in Thaumasia, Sirenum, Memnonia, and Amazonis are centered northwest of Syria with secondary centers at Thaumasia, Tempe Terra, Ulysses Fossae, and western Valles Marineris. Late Hesperian/Early Amazonian (stage 4) structures around Alba Patera, the northeast trending alignment of Tharsis Montes, and Olympus Mons appears centered on Alba Patera. Stage 5 structures (Middle-Late Amazonian) represent the last pulse of Tharsis-related activity and are found around the large shield volcanoes and are centered near Pavonis Mons. Tectonic activity around Tharsis began in the Noachian and generally decreased through geologic time to the Amazonian. Statistically significant radial distributions of structures formed during each stage, centered at different locations within the higher elevations of Tharsis. Secondary centers of radial structures during many of the stages appear related to previously identified local magmatic centers that formed at different times and locations throughout Tharsis. Copyright 2001 by

  7. The High Resolution Imaging Science Experiment (HiRISE) during MRO's Primary Science Phase (PSP)

    USGS Publications Warehouse

    McEwen, A.S.; Banks, M.E.; Baugh, N.; Becker, K.; Boyd, A.; Bergstrom, J.W.; Beyer, R.A.; Bortolini, E.; Bridges, N.T.; Byrne, S.; Castalia, B.; Chuang, F.C.; Crumpler, L.S.; Daubar, I.; Davatzes, A.K.; Deardorff, D.G.; DeJong, A.; Alan, Delamere W.; Dobrea, E.N.; Dundas, C.M.; Eliason, E.M.; Espinoza, Y.; Fennema, A.; Fishbaugh, K.E.; Forrester, T.; Geissler, P.E.; Grant, J. A.; Griffes, J.L.; Grotzinger, J.P.; Gulick, V.C.; Hansen, C.J.; Herkenhoff, K. E.; Heyd, R.; Jaeger, W.L.; Jones, D.; Kanefsky, B.; Keszthelyi, L.; King, R.; Kirk, R.L.; Kolb, K.J.; Lasco, J.; Lefort, A.; Leis, R.; Lewis, K.W.; Martinez-Alonso, S.; Mattson, S.; McArthur, G.; Mellon, M.T.; Metz, J.M.; Milazzo, M.P.; Milliken, R.E.; Motazedian, T.; Okubo, C.H.; Ortiz, A.; Philippoff, A.J.; Plassmann, J.; Polit, A.; Russell, P.S.; Schaller, C.; Searls, M.L.; Spriggs, T.; Squyres, S. W.; Tarr, S.; Thomas, N.; Thomson, B.J.; Tornabene, L.L.; Van Houten, C.; Verba, C.; Weitz, C.M.; Wray, J.J.

    2010-01-01

    The High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter (MRO) acquired 8 terapixels of data in 9137 images of Mars between October 2006 and December 2008, covering ???0.55% of the surface. Images are typically 5-6 km wide with 3-color coverage over the central 20% of the swath, and their scales usually range from 25 to 60 cm/pixel. Nine hundred and sixty stereo pairs were acquired and more than 50 digital terrain models (DTMs) completed; these data have led to some of the most significant science results. New methods to measure and correct distortions due to pointing jitter facilitate topographic and change-detection studies at sub-meter scales. Recent results address Noachian bedrock stratigraphy, fluvially deposited fans in craters and in or near Valles Marineris, groundwater flow in fractures and porous media, quasi-periodic layering in polar and non-polar deposits, tectonic history of west Candor Chasma, geometry of clay-rich deposits near and within Mawrth Vallis, dynamics of flood lavas in the Cerberus Palus region, evidence for pyroclastic deposits, columnar jointing in lava flows, recent collapse pits, evidence for water in well-preserved impact craters, newly discovered large rayed craters, and glacial and periglacial processes. Of particular interest are ongoing processes such as those driven by the wind, impact cratering, avalanches of dust and/or frost, relatively bright deposits on steep gullied slopes, and the dynamic seasonal processes over polar regions. HiRISE has acquired hundreds of large images of past, present and potential future landing sites and has contributed to scientific and engineering studies of those sites. Warming the focal-plane electronics prior to imaging has mitigated an instrument anomaly that produces bad data under cold operating conditions. ?? 2009 Elsevier Inc.

  8. Eridania Basin: An ancient paleolake floor as the next landing site for the Mars 2020 rover

    NASA Astrophysics Data System (ADS)

    Pajola, Maurizio; Rossato, Sandro; Carter, John; Baratti, Emanuele; Pozzobon, Riccardo; Erculiani, Marco Sergio; Coradini, Marcello; McBride, Karen

    2016-09-01

    The search for traces of past Martian life is directly connected to ancient paleolakes, where ponding water or low-energy water fluxes were present for long time intervals. The Eridania paleolakes system, located along the 180° meridian, is one of the largest lacustrine environments that were once present on Mars. Morphological features suggest that it was constituted by connected depressions filled by water to maximum depths of ∼2400 m and a volume of at least 562,000 km3. We focused our attention on the northern side of the Eridania Basin, where high-albedo, uneven patches of material characterized by the absence of dust are present. Based on OMEGA and CRISM orbital imaging spectroscopy data, a large clay-bearing unit has been identified there. In particular, a set of aqueous minerals in present in the stratigraphy, being visible through erosional windows in the first several tens of meters of the sedimentary sequence. Below this capping unit, a thin Al-rich clay stratum attributable to Al-smectite and/or kaolins is present. This overlies a Fe-rich clay stratum, attributable to the nontronite smectite. At the base of the mineralogic sequence a stratum that could be either a zeolite or more likely a hydrated sulfate is present. In addition, small deposits of alunite (a rare phase on Mars), and jarosite are here found at several locations. Such stratigraphy is interpreted as originating from a surface weathering process similar to terrestrial abiotic pedogenesis; nonetheless, possible exobiologic processes can be also invoked to explain it. NASA's Spirit rover landed on Gusev crater in 2004, near the mouth of the Ma'adim Vallis, which connects this crater with the considered paleolakes system. The Eridania site provides the unique opportunity to complete the measurements obtained in Gusev crater, while investigating the exposed mineralogical sequence in its depositionary setting. In addition, the extremely favorable landing parameters, such as elevation, slope

  9. The Martian Outflow Channels: Mgs Sheds New Light On Viking and Pathfinder Results

    NASA Astrophysics Data System (ADS)

    Lanz, J.; Jaumann, R.

    The Mars Global Surveyor (MGS) Mission has, as most successful missions before, given stunningly new insights in the processes that shaped the Martian surface. But how do these findings and observations fit in the context of our pre-MGS knowledge? and do they fit at all? Combining data from the Viking, Pathfinder and MGS Missions, erosion processes in the circum-Chryse Region have been newly and extensively examined. Maximum discharge rates and flow velocities within the major outflow channels were calculated as well as sediment transport and sediment volumes eroded by the flows evaluating the erosion balance of the region. In a second step a detailed study of the available high resolution MOC-Images and lower resolution MOC and Viking context images was performed to evaluate the geologic and morphologic inventory of the outflow chan- nels. Focusing on morphologic and hydrologic differences to terrestrial outflow chan- nels as well as differences to earlier pre-MGS studies, theories and hypothesis con- cerning the outflow channels have been tested for their validity. New hydrologic cal- culations e.g. give different results than previously measured (e.g. Carr 1979, Robin- son &Tanaka 1990, Komatsu &Baker 1997). Maximum discharge rates are generally smaller (see also Williams et al. 2000), in some cases up to a factor of 2 to 3 (e.g. Ares Vallis), having a strong impact on the northern ocean theory. Some morphologic fea- tures that are typical for terrestrial flood features (such as inner channels, bar deposits, gravel dunes, etc) could not or not clearly be identified in any of the large outflow channels even in high resolution MOC-imagery. Younger resurfacing processes might have covered or obscured them. Others are hard to distinguish from non-fluvial, i.e. eo- lian, features from satellite images. Nevertheless, the overall absence of such features in the outflow channels is striking and shows again that processes on Mars differ sig- nificantly from those on

  10. Diverse Aqueous Conditions on Mars from New Orbital Detections of Carbonate and Sulfate

    NASA Astrophysics Data System (ADS)

    Wray, James J.; Squyres, S. W.

    2010-10-01

    Diverse aqueous environments on ancient Mars have been a key inference from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on NASA's Mars Reconnaissance Orbiter, which has identified many alteration minerals in a range of settings [e.g., 1-4]. Here we report two new minerals detected using CRISM. In the southern highlands northwest of the Hellas basin, a mid-sized crater exposes carbonate in its central uplift. Spectral absorptions at 1, 2.33, and 2.53 microns are most consistent with Fe-carbonate, distinct from the Mg-carbonates identified from orbit by [5]. Fe-carbonate is associated with Mg-phyllosilicate in fractured materials formerly buried kilometers beneath the surface, and--like the Mg/Fe-carbonate found by the Spirit rover [6]--suggests a reducing, neutral-to-alkaline alteration environment. One of the largest phyllosilicate exposures on Mars occurs in the Mawrth Vallis region [e.g., 7]. We identify bassanite (Ca-sulfate hemihydrate) in layers underlying the phyllosilicate-bearing beds [8], a stratigraphy distinct from that predicted by global models of martian aqueous history [9]. Bassanite could have formed via acid-sulfate alteration of Ca-carbonate, through dehydration of gypsum, or under hydrothermal conditions [10]. These detections expand the known mineralogic diversity of Mars and the range of environments to explore for past habitability. [1] Mustard, J. F. et al. (2008) Nature 454, 305-309. [2] Murchie, S. L. et al. (2009) J. Geophys. Res. 114, E00D06. [3] Ehlmann, B. L. et al. (2009) J. Geophys. Res. 114, E00D08. [4] Wray, J. J. et al. (2009) Geology 37, 1043-1046. [5] Ehlmann, B. L. et al. (2008) Science 322, 1828-1832. [6] Morris, R. V. et al. Science, in press, doi:10.1126/science.1189667. [7] Poulet, F. et al. (2005) Nature 438, 623-627. [8] Wray, J. J. et al. Icarus, in press, doi:10.1016/j.icarus.2010.06.001. [9] Bibring, J.-P. et al. (2006) Science 312, 400-404. [10] Vaniman, D. T. et al. (2009) LPSC 40, 1654.

  11. Randomized controlled trial of a book-sharing intervention in a deprived South African community: effects on carer-infant interactions, and their relation to infant cognitive and socio-emotional outcome

    PubMed Central

    Murray, Lynne; De Pascalis, Leonardo; Tomlinson, Mark; Vally, Zahir; Dadomo, Harold; MacLachlan, Brenda; Woodward, Charlotte; Cooper, Peter J.

    2017-01-01

    Background Consistent with evidence from high income countries, we previously showed that, in an informal peri-urban settlement in a low-middle income country, training parents in book-sharing with their infants benefitted infant language and attention (Vally et al., 2015). Here, we investigated whether these benefits were explained by improvements in carer-infant interactions in both book-sharing and non-book-sharing contexts. We also explored whether infant socio-emotional development benefitted from book-sharing. Methods We conducted a randomized controlled trial in Khayelitsha, South Africa. Carers of 14–16 month-old infants were randomized to 8 weeks’ training in book-sharing (n = 49) or a wait list control group (n = 42). In addition to the cognitive measures reported previously, independent assessments were made at base line and follow-up of carer-infant interactions during book-sharing and toy play. Assessments were also made, at follow-up only, of infant pro-social behaviour in a ‘help task’, and of infant imitation of doll characters’ non-social actions and an interpersonal interaction. Eighty-two carer-infant pairs (90%) were assessed at follow-up. (Trial registration ISRCTN39953901). Results Carers who received the training showed significant improvements in book-sharing interactions (sensitivity, elaborations, reciprocity), and, to a smaller extent, in toy-play interactions (sensitivity). Infants in the intervention group showed a significantly higher rate of pro-social behaviour, and tended to show more frequent imitation of the interpersonal interaction. Improvements in carer behaviour during book-sharing, but not during toy play, mediated intervention effects on all infant cognitive outcomes, and tended to mediate intervention effects on infant interpersonal imitation. Conclusions Training in book sharing, a simple, inexpensive intervention that has been shown to benefit infant cognitive development in a low-middle income country, also

  12. The Mars Pathfinder Mission

    NASA Astrophysics Data System (ADS)

    Golombek, M. P.

    1996-09-01

    The Mars Pathfinder mission is a Discovery class mission that will place a small lander and rover on the surface of Mars on July 4, 1997. The Pathfinder flight system is a single small lander, packaged within an aeroshell and back cover with a back-pack-style cruise stage. The vehicle will be launched, fly independently to Mars, and enter the atmosphere directly on approach behind the aeroshell. The vehicle is slowed by a parachute and 3 small solid rockets before landing on inflated airbags. Petals of a small tetrahedron shaped lander open up, to right the vehicle. The lander is solar powered with batteries and will operate on the surface for up to a year, downlinking data on a high-gain antenna. Pathfinder will be the first mission to use a rover, with 3 imagers and an alpha proton X-ray spectrometer, to characterize the rocks and soils in a landing area over hundreds of square meters on Mars, which will provide a calibration point or "ground truth" for orbital remote sensing observations. The rover (includes a series of technology experiments), the instruments (including a stereo multispectral surface imager on a pop up mast and an atmospheric structure instrument-surface meteorology package) and the telemetry system will allow investigations of: the surface morphology and geology at meter scale, the petrology and geochemistry of rocks and soils, the magnetic properties of dust, soil mechanics and properties, a variety of atmospheric investigations and the rotational and orbital dynamics of Mars. Landing downstream from the mouth of a giant catastrophic outflow channel, Ares Vallis, offers the potential of identifying and analyzing a wide variety of crustal materials, from the ancient heavily cratered terrain, intermediate-aged ridged plains and reworked channel deposits, thus allowing first-order scientific investigations of the early differentiation and evolution of the crust, the development of weathering products and early environments and conditions on Mars.

  13. Meteorological predictions for Mars 2020 Exploration Rover high-priority landing sites throug MRAMS Mesoscale Modeling

    NASA Astrophysics Data System (ADS)

    Pla-García, Jorge; Rafkin, Scot C. R.

    2015-04-01

    The Mars Regional Atmospheric Modeling System (MRAMS) is used to predict meteorological conditions that are likely to be encountered by the Mars 2020 Exploration Rover at several proposed landing sites during entry, descent, and landing (EDL). The meteorology during the EDL window at most of the sites is dynamic. The intense heating of the lower atmosphere drives intense thermals and mesoscale thermal circulations. Moderate mean winds, wind shear, turbulence, and vertical air currents associated with convection are present and potentially hazardous to EDL [1]. Nine areas with specific high-priority landing ellipses of the 2020 Rover, are investigated: NE Syrtis, Nili Fossae, Nili Fossae Carbonates, Jezero Crater Delta, Holden Crater, McLaughlin Crater, Southwest Melas Basin, Mawrth Vallis and East Margaritifer Chloride. MRAMS was applied to the landing site regions using nested grids with a spacing of 330 meters on the innermost grid that is centered over each landing site. MRAMS is ideally suited for this investigation; the model is explicitly designed to simulate Mars' atmospheric thermal circulations at the mesoscale and smaller with realistic, high-resolution surface properties [2, 3]. Horizontal wind speeds, both vertical profiles and vertical cross-sections wind speeds, are studied. For some landing sites simulations, two example configurations -including and not including Hellas basin in the mother domain- were generated, in order to study how the basin affects the innermost grids circulations. Afternoon circulations at all sites pose some risk entry, descent, and landing. Most of the atmospheric hazards are not evident in current observational data and general circulation model simulations and can only be ascertained through mesoscale modeling of the region. Decide where to go first and then design a system that can tolerate the environment would greatly minimize risk. References: [1] Rafkin, S. C. R., and T. I. Michaels (2003), J. Geophys. Res., 108(E12

  14. Hydrogeological Interpretation of Candidate Origin Sites for Martian Meteorite ALH84001

    NASA Technical Reports Server (NTRS)

    Gulick, Virginia C.; McKay, Chris; Cuzzi, Jeffrey N. (Technical Monitor)

    1996-01-01

    Barlow (this meeting) has identified two potential source craters for the martian meteorite ALH84001. The craters are at 11.7 deg S, 243.3 deg W (Mare Tyrrhenum site) and 14.0 deg S, 343.5 deg W (Sinus Sabaeus site). As noted by Barlow, both craters lie in the heavily cratered terrain (HCT) and are adjacent to fluvial valleys, Here I explore the fluvial history of these areas based upon the surrounding valley morphology. The most prominent valley network at the Sabaeus site is Evros Vallis. This wide, flat-floored valley is approximately 600 km long with an average width of 2.5 km and a depth of 220 m. The eroded volume of the entire Evros network is approximately 6 x 10(exp 11) cc. This is typical for networks located in the heavily cratered terrain (e.g. Warrego and Parana Valles). Evros is also an isolated valley system. No similar networks are found in the surrounding terrain. Thus it is unlikely that Evros formed as a result of widespread rainfall. A localized water source, such as discharge of a hydrothermal system or localized melting of snowfall, seems more consistent Previous modeling has demonstrated that only hydrothermal systems associated with high permeability subsurfaces can discharge sufficient water to form a valley network. The bulk of the discharge from such systems is consequently low temperature, slightly heated water Precipitation of calcium carbonate by low temperature fluids is consistent with most interpretations of the geochemistry of ALH84001. Available imagery at the Tyrrhenum site is of lesser quality. While eroded units of the HCT are nearby, there are no comparable well developed valley networks at this site. Erosion is instead manifested predominantly as gullies on slopes. This style of erosion suggests that water was not present at this site for the length of time as at the more integrated Sabaeus site. The superposition of fluidized ejecta blankets suggests however that ground water or ground ice was still present at this locality

  15. Exploring Gusev with MER A

    NASA Astrophysics Data System (ADS)

    Grin, E. A.; Cabrol, N. A.; Des Marais, D.; Farmer, J.; Greeley, R.; Carr, M.; Kramer, M.; Moore, J.; Sutter, B.; Fike, D.; Kuzmin, R.; Grant, F.; Barlow, N.; Newsom, H.; Tanaka, K.; Urquhart, M.; de Goursac, O.; Grisby, B.

    2002-12-01

    Gusev will be an outstanding candidate to achieve the 2003 MER mission goals. The crater has collected sediments from a diversity of parent rocks in the vast Maadim Vallis watershed over a period of three billion years. Because of the interaction between Gusev and Maadim, it has been proposed that a significant volume of the sedimentary material in the crater is of aqueous origin. Mars Odyssey has shown that the hydrogen abundance in the Gusev region is higher than average at corresponding latitudes. This observation could be consistent with a past long lived aqueous activity. The presence of aqueous material is central to the MER mission because it can provide clues about the past water history, climate changes, and the potential habitability of Mars. However, while Gusev is recognized as a primary site because of its past fluvio lacustrine activity, the geological diversity and history of its immediate surroundings makes it exceptional and provides the foundation for an exciting exploration leading to key discoveries. In addition to aqueous, many other processes can have contributed to the material in the crater basin: volcanic, Apollinaris patera is only 200 km away, aeolian, glacial, and global airfall processes. How to identify the signature of each process? What was their succession in time? Do we see the evolution from perennial to more episodic lakes? Do we see interaction between volcanic, glacial, aeolian and lacustrine processes? What was the recurrence of dry episodes? What type of measurements can provide a definitive answer for each of these questions in the 600 m traverse range that the rover will accomplish? What diversity can we also expect in this range? Finally, the uniqueness and potential of Gusev does not reside only in this exceptional diversity. As there is evidence for long lived lake episodes, Gusev also offers the unique possibility to study for the first time the results of the in situ formation of aqueous sediments and minerals in their

  16. Randomized controlled trial of a book-sharing intervention in a deprived South African community: effects on carer-infant interactions, and their relation to infant cognitive and socioemotional outcome.

    PubMed

    Murray, Lynne; De Pascalis, Leonardo; Tomlinson, Mark; Vally, Zahir; Dadomo, Harold; MacLachlan, Brenda; Woodward, Charlotte; Cooper, Peter J

    2016-12-01

    Consistent with evidence from high-income countries (HICs), we previously showed that, in an informal peri-urban settlement in a low-middle income country, training parents in book sharing with their infants benefitted infant language and attention (Vally, Murray, Tomlinson, & Cooper, ). Here, we investigated whether these benefits were explained by improvements in carer-infant interactions in both book-sharing and non-book-sharing contexts. We also explored whether infant socioemotional development benefitted from book sharing. We conducted a randomized controlled trial in Khayelitsha, South Africa. Carers of 14-16-month-old infants were randomized to 8 weeks' training in book sharing (n = 49) or a wait-list control group (n = 42). In addition to the cognitive measures reported previously, independent assessments were made at base line and follow-up of carer-infant interactions during book sharing and toy play. Assessments were also made, at follow-up only, of infant prosocial behaviour in a 'help task', and of infant imitation of doll characters' nonsocial actions and an interpersonal interaction. Eighty-two carer-infant pairs (90%) were assessed at follow-up. (Trial registration ISRCTN39953901). Carers who received the training showed significant improvements in book-sharing interactions (sensitivity, elaborations, reciprocity), and, to a smaller extent, in toy-play interactions (sensitivity). Infants in the intervention group showed a significantly higher rate of prosocial behaviour, and tended to show more frequent imitation of the interpersonal interaction. Improvements in carer behaviour during book sharing, but not during toy play, mediated intervention effects on all infant cognitive outcomes, and tended to mediate intervention effects on infant interpersonal imitation. Training in book sharing, a simple, inexpensive intervention that has been shown to benefit infant cognitive development in a low-middle income country, also shows promise for

  17. Mapping Rock and Soil Units in the MPF IMP SuperPan Using a Kohonen Self Organizing Map

    NASA Technical Reports Server (NTRS)

    Farrand, W.; Merenyi, E.; Murchie, S.; Barnouin-Jha, O.; Johnson, J.

    2004-01-01

    The 1997 Mars Pathfinder mission provided information on a site in the Ares Vallis floodplain. Initial analysis of multispectral data from the Imager for Mars Pathfinder (IMP) indicated the presence of only a single rock type, the 'gray rock' spectral class and various coated variants thereof (e.g., 'maroon rock'). Continued analysis of the IMP 'SuperPan' mosaic has confirmed multiple examples of a second 'black rock' spectral class existing as small cobbles in the near field and as boulders in the far field. These results are consistent with recent analysis of MGS Thermal Emission Spectrometer (TES) data which indicates that there is likely a mix of both 'Surface Type 1' (ST1) and 'Surface Type 2' (ST2) spectral classes at the MPF landing site. Nominally, the black rock spectral class would correspond to ST1 (basalts) and 'gray rock' would correspond to ST2 (andesites). Orbital remote sensing has also revealed the pervasive presence of layering on Mars. Recently it was suggested that there are extensive outcrops of the black rock spectral class in the SuperPan far field on the flanks of the Twin Peaks and on the rim of Big Crater. These authors suggested that these exposures represented outcrops of black rock from beneath a surficial, flood deposited layer. In this work, we have reexamined the MPF IMP SuperPan mosaic using an artificial neural network self organizing map (SOM) processing architecture in order to classify the distribution of spectral classes within the SuperPan. In this paper, we present initial results from that work and draw specific attention to a subset of the identified spectral classes in order to address questions relating to whether there are extensive exposures of black rock in the IMP far field, what other materials might be exposed in the far field, and what evidence there is for subsurface layering at the MPF landing site.

  18. Ventifacts at the Pathfinder landing site

    USGS Publications Warehouse

    Bridges, N.T.; Greeley, R.; Haldemann, A.F.C.; Herkenhoff, K. E.; Kraft, M.; Parker, T.J.; Ward, A.W.

    1999-01-01

    About half of the rocks at the Mars Pathfinder Ares Vallis landing site appear to be ventifacts, rocks abraded by windborne particles. Comparable resolution images taken by the Imager for Mars Pathfinder (IMP) camera and the Viking landers show that ventifacts are more abundant at the Pathfinder site. The ventifacts occur in several forms, including rocks with faceted edges, finger-like projections, elongated pits, flutes, grooves, and possible rills. The trends of elongated pits, flutes, grooves, and rills cluster at ???280-330?? clockwise from north and generally dip 10-30?? away from their trend direction. These orientations are indicative of southeast to northwest winds and differ from the trend of wind tails at the landing site, the direction of local wind streaks, and predictions of the Global Circulation Model, all of which indicate northeast to southwest winds. The disparity between these data sets strongly suggests that local circulation patterns have changed since the abrasion of the ventifacted rocks. The greater number of ventifacts at the Pathfinder site compared to either of the Viking sites is most easily explained as being due to a larger supply of abrading particles, composed of either sand-sized grains or indurated dust aggregates, and higher surface roughness, which should increase the momentum of saltating grains. The Pathfinder ventifacts may have formed shortly after the deposition of outflow channel sediments nearly 2 Gry ago, when a large local supply of abrading particles should have been abundant and atmospheric conditions may have been more conducive to rock abrasion from saltating grains. Based on how ventifacts form on Earth, the several ventifact forms seen at the Pathfinder site and their presence on some rocks but not on others are probably due to local airflow conditions, original rock shape, exposure duration, rock movement, and to a lesser extent, rock lithology. The abundance of ventifacts at the Pathfinder site, together with

  19. Sleep and Quality of Life in Urban Poverty: The Effect of a Slum Housing Upgrading Program

    PubMed Central

    Simonelli, Guido; Leanza, Yvan; Boilard, Alexandra; Hyland, Martín; Augustinavicius, Jura L.; Cardinali, Daniel P.; Vallières, Annie; Pérez-Chada, Daniel; Vigo, Daniel E.

    2013-01-01

    Study Objectives: To evaluate the effect of a housing transition on sleep quality and quality of life in slum dwellers, participating in a slum housing upgrading program. Design: Observational before-and-after study with a convergent-parallel mixed method design. Setting: Five slums located in the metropolitan area of Buenos Aires, Argentina. Participants: A total of 150 slum dwellers benefited by a housing program of the nonprofit organization TECHO (spanish word for “roof”). Interventions: Participants moved from their very low-quality house to a basic prefabricated 18 m2 modular house provided by TECHO. Measurements and Results: The Pittsburgh Sleep Quality Index (PSQI) and World Health Organization Quality of Life brief scale (WHOQOL-BREF) were administered before and after housing upgrading. Data about housing conditions, income, education, sleeping conditions, and cardiovascular risk were also collected. Semistructured interviews were used to expand and nuance quantitative data obtained from a poorly educated sample. Results showed that sleep quality significantly increased after the housing program (z = -6.57, P < 0.001). Overall quality of life (z = -6.85, P < 0.001), physical health domain (z = -4.35, P < 0.001), psychological well-being domain (z = -3.72, P < 0.001) and environmental domain (z = -7.10, P < 0.001) of WHOQOL-BREF were also improved. Interviews demonstrated the importance of serenity for improving quality of life. Conclusions: A minimal improvement in the quality of basic housing can significantly increase sleep quality and quality of life among slum dwellers. Understanding sleep and daily life conditions in informal urban settlements could help to define what kind of low-cost intervention may improve sleep quality, quality of life, and reduce existent sleep disparity. Citation: Simonelli G; Leanza Y; Boilard A; Hyland M; Augustinavicius JL; Cardinali DP; Vallières A; Pérez-Chada D; Vigo DE. Sleep and quality of life in urban poverty

  20. Old Geology and New Geology

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 28 May 2003

    Mangala Vallis one of the large outflow channels that channeled large quantities of water into the northern lowlands, long ago on geological timescales. This valley is one of the few in the southern hemisphere, as well as one of the few west of the Tharsis bulge. A closer look at the channel shows more recent weathering of the old water channel: the walls of the channel show small, dark slope streaks that form in dusty areas; and much of the surrounding terrain has subtle linear markings trending from the upper left to the lower right, which are probably features sculpted and streamlined by the wind. Geology still shapes the surface of Mars today, but its methods over the eons have changed.

    Image information: VIS instrument. Latitude -6, Longitude 209.6 East (150.4 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in

  1. Modeling Cooling Rates of Martian Flood Basalt Columns

    NASA Astrophysics Data System (ADS)

    Weiss, D. K.; Jackson, B.; Milazzo, M. P.; Barnes, J. W.

    2011-12-01

    Columnar jointing in large basalt flows have been extensively studied and can provide important clues about the emplacement conditions and cooling history of a basalt flow. The recent discovery of basalt columns on Mars in crater walls near Marte Vallis provides an opportunity to infer conditions on early Mars when the Martian basalt flows were laid down. Comparison of the Martian columns to Earth analogs allows us to gain further insight into the early Martian climate, and among the best terrestrial analogs are the basalt columns in the Columbia River Basalt Group (CRBG) in eastern Washington. The CRBG is one of the youngest (< 17 Myrs old) and most extensively studied basalt provinces in the world, extending over 163,700 square km with total thickness exceeding 1 km in some places. The morphologies and textures of CRBG basalt columns suggest that in many places flows ~100 m thick cooled at uniform rates, even deep in the flow interior. Such cooling seems to require the presence of water in the column joints since the flow interiors should have cooled much more slowly than the flow margins if conductive cooling dominated. Secondary features, such pillow basalts, likewise suggest the basalt flows were in direct contact with standing water in many places. At the resolution provided by the orbiting HiRISE camera (0.9 m), the Martian basalt columns resemble the CRBG columns in many respects, and so, subject to important caveats, inferences linking the morphologies of the CRBG columns to their thermal histories can be extended in some respects to the Martian columns. In this presentation, we will describe our analysis of the HiRISE images of the Martian columns and what can be reasonably inferred about their thermal histories and the conditions under which they were emplaced. We will also report on a field expedition to the CRBG in eastern Washington State. During that expedition, we surveyed basalt column outcrops on the ground and from the air using Unmanned Aerial

  2. Classification of igneous rocks analyzed by ChemCam at Gale crater, Mars

    DOE PAGES

    Cousin, Agnes; Sautter, Violaine; Payré, Valérie; ...

    2017-02-09

    Several recent studies have revealed that Mars is not a simple basalt-covered planet, but has a more complex geological history. In Gale crater on Mars, the Curiosity rover discovered 59 igneous rocks. This article focuses on their textures (acquired from the cameras such as MAHLI and MastCam) and their geochemical compositions that have been obtained using the ChemCam instrument. Light-toned crystals have been observed in most of the rocks. They correspond to feldspars ranging from andesines/oligoclases to anorthoclases and sanidines in the leucocratic vesiculated rocks. Darker crystals observed in all igneous rocks (except the leucocratic vesiculated ones) were analyzed bymore » LIBS and mainly identified as Fe-rich pigeonites and Fe-augites. Iron oxides have been observed in all groups whereas F-bearing minerals have been detected only in few of them. From their textural analysis and their whole-rock compositions, all these 59 igneous rocks have been classified in five different groups; from primitive rocks i.e. dark aphanitic basalts/basanites, trachybasalts, tephrites and fine/coarse-grained gabbros/norites to more evolved materials i.e. porphyritic trachyandesites, leucocratic trachytes and quartz-diorites. The basalts and gabbros are found all along the traverse of the rover, whereas the felsic rocks are located before the Kimberley formation, i.e. close to the Peace Vallis alluvial fan deposits. This suggests that these alkali rocks have been transported by fluvial activity and could come from the Northern rim of the crater, and may correspond to deeper strata buried under basaltic regolith (Sautter et al., 2015). Some of the basaltic igneous rocks are surprisingly enriched in iron, presenting low Mg# similar to the nakhlite parental melt that cannot be produced by direct melting of the Dreibus and Wanke (1986) martian primitive mantle. The basaltic rocks at Gale are thus different from Gusev basalts. They could originate from different mantle reservoirs

  3. The M3 project

    NASA Astrophysics Data System (ADS)

    Poulet, Francois; Carter, John; Riu, Lucie; Martinez, Antoine; Bibring, Jean-Pierre; Gondet, Brigitte; Langevin, Yves

    2017-10-01

    been performed on two regions that exhibit the greatest mineral diversity of hydrated minerals on Mars: Nilo-Syrtis region and Mawrth Vallis/Oxia Planum region. Mineral maps of various hydrated and primary phases will be presented.

  4. Constraints on Environmental Conditions on Mars during Periods of Alluvial Fan Formation: Results from Landform Evolution Modeling

    NASA Astrophysics Data System (ADS)

    Morgan, A. M.; Howard, A. D.; Moore, J. M.

    2015-12-01

    As depositional systems forming within enclosed crater basins, the Late Noachian and Hesperian -aged [1] alluvial fans on Mars (including the Peace Vallis fan in Gale crater) may be representative of the last vestiges of widespread fluvial activity on the planet's surface, an era during which the climate transitioned from a wetter early Mars to the cold and dry planet we observe today. We have constructed a landform evolution model that combines sediment transport with channel avulsion to study the evolution of a fan-forming channel network over timescales of decades to hundreds of thousands of years. We aim to address two related questions: (1) what were the characteristics of water discharge (flow magnitude and duration); and (2) what are the associated implications for the responsible climatic environment (e.g. amount and frequency of precipitation sourcing the fans). The model uses a cellular network with a grid spacing set equal to the channel width. Two end-members of sediment are transported through the channel network: gravel bedload and fine grained material that is deposited overbank as a function of distance and elevation difference from an active channel. Overbank deposition creates channel levees, which must be overtopped for the channel to undergo an avulsion. By recording the relative amounts of bedload and overbank deposition, the 3-D stratigraphy is recorded as the fan is constructed. Using measures such as channel width, relative proportions of channel versus overbank deposited sediment, and frequency of channel branching, output is statistically compared with digital elevation models that we been produced from high-resolution CTX and HiRISE stereo pairs. Our modeling suggests that the fans formed from many flow events over many thousands of years, in agreement with estimations based on geomorphological observations by [2]. We are continuing to refine the model to test for varying patterns of precipitation, duricrusts, and limits on sediment

  5. Evidence for an Ancient Periglacial Climate in Gale Crater, Mars

    NASA Astrophysics Data System (ADS)

    Fairén, A. G.; Oehler, D. Z.; Mangold, N.; Hallet, B.; Le Deit, L.; Williams, A.; Sletten, R. S.; Martínez-Frías, J.

    2016-12-01

    Decameter-scale polygons occur extensively in the lower Peace Vallis Fan of Gale crater, in the Bedded Fractured (BF) Unit, north of Yellowknife Bay (YKB) that was examined and drilled by the Curiosity rover. To gain insight into the origin of these polygons, we studied image data from the Context (CTX) and High Resolution Imaging Science Experiment (HiRISE) cameras on Mars Reconnaissance Orbiter and compared results to the geology of the fan. The polygons are 4 to 30 m across, square to rectangular, and defined by 0.5 to 4 m-wide linear troughs that probably reflect cm-wide, quasi-vertical fractures below the surface. Polygon networks are typically orthogonal systems, with occasional circularly organized patterns, hundreds of meters across. We evaluated multiple hypotheses for the origin of the polygons and concluded that thermal-contraction fracturing during cooling of ice-rich permafrost is most consistent with the sedimentary nature of the BF Unit, the morphology/geometry of the polygons, their restriction to the coarse-grained Gillespie Lake Member, and geologic context. Most of these polygons are confined to the Hesperian BF Unit and appear to be ancient, though individual polygon fractures may have been reactivated in more recent periods, perhaps due to stresses developed with exhumation or as the planet grew colder and drier. Some of the circular networks resemble ice-wedge polygons in thermokarst depressions and collapsed pingos, as seen in periglacial environments of the Arctic. An analog to collapsed pingos could be supported by modeling work of Andrews-Hanna et al. (2012, LPSC; 2012, 3rd Conf. Early Mars) suggesting that Gale was uniquely positioned for significant influx of ground water early its history. Also, results from Curiosity demonstrating limited chemical weathering and a past freshwater lake in YKB (Grotzinger et al., 2014, Science 343) would be consistent with an early periglacial setting. Our conclusions support an ancient, cold and wet

  6. Iron mineralogy of the surface of Mars from the 1 μm band spectral properties

    NASA Astrophysics Data System (ADS)

    Carrozzo, F. G.; Altieri, F.; Bellucci, G.; Poulet, F.; D'Aversa, E.; Bibring, J.-P.

    2012-10-01

    We study the 1 μm absorption from OMEGA/MEX spectra to map Martian iron mineralogy at a global scale. This band is covered on the left by the VNIR (visible and near infrared) OMEGA channel and on the right by the SWIR (short wavelengths infrared) one. We first perform a systematic spatial coregistration of the two channels after an improvement of the VNIR radiometric calibration. The update of the VNIR Instrumental Transfer Function (ITF) and the internal stray-light estimation is based on the spectra of the Phobos red units and of the water ice north polar cap of Mars, which have been fitted according to an iterative process. The level of the signal in the blue wavelength range, previously systematically overestimated due to a stray-light residual and the general shape of the spectrum for λ > 0.7 μm are improved . Global maps of the 1 μm signature have been derived from 9 new spectral indices. The largest values of the 1 μm band integral are found in Noachian terrains and in the dunes around the north polar cap. In the south polar region, an area centered at ˜155°W and ˜83°S is mapped as a distinctive spectral unit, dominated by pyroxene. The northern lowlands of Mars together with other dark terrains located in the northern hemisphere show very low values of some spectral indices due to the negative spectral slope in the NIR. This behavior is consistent with the presence of weathered basalts with a possible glassy or amorphous component. Among the hydrated terrains, the only ones that can be isolated by studying the 1 μm band are those located in Terra Meridiani, Aram Chaos and Capri Chasma, enriched in sulfate and hematite. On the other hand, the sulfates of the dark dunes surrounding the northern polar cap and the phyllosilicates of the bright hydrated deposits of Mawrth Vallis cannot be isolated combining the parameters used in this study. This suggests that their distinctive mineralogy does not affect the 1 μm band, remaining similar to the global

  7. Detection of spatio-temporal variability of air temperature and precipitation based on long-term meteorological station observations over Tianshan Mountains, Central Asia

    NASA Astrophysics Data System (ADS)

    Xu, Min; Kang, Shichang; Wu, Hao; Yuan, Xu

    2018-05-01

    As abundant distribution of glaciers and snow, the Tianshan Mountains are highly vulnerable to changes in climate. Based on meteorological station records during 1960-2016, we detected the variations of air temperature and precipitation by using non-parametric method in the different sub-regions and different elevations of the Tianshan Mountains. The mutations of climate were investigated by Mann-Kendall abrupt change test in the sub-regions. The periodicity is examined by wavelet analysis employing a chi-square test and detecting significant time sections. The results show that the Tianshan Mountains experienced an overall rapid warming and wetting during study period, with average warming rate of 0.32 °C/10a and wet rate of 5.82 mm/10a, respectively. The annual and seasonal spatial variation of temperature showed different scales in different regions. The annual precipitation showed non-significant upward trend in 20 stations, and 6 stations showed a significant upward trend. The temperatures in the East Tianshan increased most rapidly at rates of 0.41 °C/10a. The increasing magnitudes of annual precipitation were highest in the Boertala Vally (8.07 mm/10a) and lowest in the East Tianshan (2.64 mm/10a). The greatest and weakest warming was below 500 m (0.42 °C/10a) and elevation of 1000-1500 m (0.23 °C/10a), respectively. The increasing magnitudes of annual precipitation were highest in the elevation of 1500 m-2000 m (9.22 mm/10a) and lowest in the elevation of below 500 m (3.45 mm/10a). The mutations of annual air temperature and precipitation occurred in 1995 and 1990, respectively. The large atmospheric circulation influenced on the mutations of climate. The significant periods of air temperature were 2.4-4.1 years, and annual precipitation was 2.5-7.4 years. Elevation dependency of temperature trend magnitude was not evidently in the Tianshan Mountains. The annual precipitation wetting trend was amplified with elevation in summer and autumn. The strong

  8. Quantitative topographic analysis as a guide to rover-based research on Mars

    NASA Astrophysics Data System (ADS)

    Palucis, M. C.; Dietrich, W. E.; Parker, T. J.; Sumner, D. Y.; Williams, R. M. E.; Hayes, A.; Mangold, N.; Lewis, K. W.

    2014-12-01

    Satellite imagery of Mars now provides remarkable topographic data, often better than that on Earth in many countries. For decades, researchers have identified landforms on Mars that indicated the presence of gullies, rivers, deltas, fans, and lakes, pointing to the presence of surface waters, and the apparent necessity of an active hydrologic cycle involving rain or snow. Quantitative topographic analysis has provided a means to estimate volumes of runoff, sediment transport rates, and peak flow discharges, first using orbital imagery alone and then using laser altimetery coverage and higher resolution HiRISE (1 m/px), CTX (20 m/px) and HRSC (50 m/px) topography. Our detailed topographic analysis of the Peace Vallis fan near the Curiosity rover landing site in Gale Crater (Mars) suggested that the fan entered into a pre-existing enclosed basin that would likely contain lake sediments; sedimentary, mineralogical, and chemical analysis of this region, now named Yellowknife Bay, later found this to be the case, though debate remains on the exact origin and history of the deposit. The rover is currently heading to a 5 km high sedimentary mound (Aeolis Mons) with mineral signatures hypothesized to be the result of planet-wide changes in climate. Topographic features on the mound, which correspond in elevation with other large depositional features around the crater, suggest that a succession of lakes developed post-Noachian. Within Gale, we are in a unique position to determine the extent at which topography can tell us the evolutionary history of a place on another planet, since our hypotheses can actually be tested as the Curiosity rover makes its ascent up Aeolis Mons. Along the rover's traverse, we propose based on the geomorphic record that the sediments being examined were water soaked, perhaps several times under deep lakes, and that the rover will cross shorelines that may not be well-preserved, but are worth searching for. A quantitative topographic analysis

  9. Channel with Island in False Color

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released 29 March 2004

    The Odyssey spacecraft has completed a full Mars year of observations of the red planet. For the next several weeks the Image of the Day will look back over this first mars year. It will focus on four themes: 1) the poles - with the seasonal changes seen in the retreat and expansion of the caps; 2) craters - with a variety of morphologies relating to impact materials and later alteration, both infilling and exhumation; 3) channels - the clues to liquid surface flow; and 4) volcanic flow features. While some images have helped answer questions about the history of Mars, many have raised new questions that are still being investigated as Odyssey continues collecting data as it orbits Mars.

    This false color image shows part of the Apsus Vallis region. It was collected February 2, 2003 during northern summer season. The local time is 5pm. The image shows a typical channel formation with island created in it.

    Image information: VIS instrument. Latitude 35.1, Longitude 135 East (225 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics

  10. Feldspathic Rocks and Associated Mineral Phases on Mars: Evidence for Metamorphism?

    NASA Astrophysics Data System (ADS)

    Sessa, A. M.; Wray, J. J.

    2017-12-01

    It is widely accepted that the great majority of Martian crust is basaltic, suggesting that magmatic differentiation was not a key contributor to its production. However, remote sensing studies employing thermal emission imaging instruments aboard Mars Global Surveyor and Mars Odyssey, and recent in situ analyses performed by ChemCam onboard Curiosity, have indicated the presence of more silicic, feldspar-rich rocks with minimal mafics. Using the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), conceivably similar feldspathic rocks have been reported in other locations across the surface, which include: small outcrops located in the lower stratigraphic section of eastern Vallis Marineris; light-toned, polygonally fractured outcrops exposed within flat-floored craters; as well as other erosional or structural exposures (e.g., buttes, massifs, and crater rims). These previously observed occurrences can be classified as either 1) relatively unaltered rock spectrally dominated by feldspar or 2) an altered material in which CRISM detects feldspar in addition to Al, Fe, Mg-phyllosilicates and/or zeolites. Here we report on feldspathic outcrops that differ in their geologic setting from the previously identified occurrences in that they are associated with complex craters. These outcrops are accompanied by mineral phases that are relatively rare on Mars (i.e., analcime and other zeolites, chlorite, prehnite, mica, and carbonate) and may be indicative of hydrothermal or metamorphic processes. In these craters, feldspathic rocks can be found in and around the central uplift, in crater floor deposits, and in the ejecta, with tentative trends in associated mineralogy. These spatial, and mineralogical, relationships will be illustrated by CRISM RGB composite maps overlain on Context Camera imagery for select scenes. We also report new occurrences like those identified by Carter and Poulet (2013), where feldspar and Al-phyllosilicates are the most spectrally

  11. Classification of igneous rocks analyzed by ChemCam at Gale crater, Mars

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cousin, Agnes; Sautter, Violaine; Payré, Valérie

    Several recent studies have revealed that Mars is not a simple basalt-covered planet, but has a more complex geological history. In Gale crater on Mars, the Curiosity rover discovered 59 igneous rocks. This article focuses on their textures (acquired from the cameras such as MAHLI and MastCam) and their geochemical compositions that have been obtained using the ChemCam instrument. Light-toned crystals have been observed in most of the rocks. They correspond to feldspars ranging from andesines/oligoclases to anorthoclases and sanidines in the leucocratic vesiculated rocks. Darker crystals observed in all igneous rocks (except the leucocratic vesiculated ones) were analyzed bymore » LIBS and mainly identified as Fe-rich pigeonites and Fe-augites. Iron oxides have been observed in all groups whereas F-bearing minerals have been detected only in few of them. From their textural analysis and their whole-rock compositions, all these 59 igneous rocks have been classified in five different groups; from primitive rocks i.e. dark aphanitic basalts/basanites, trachybasalts, tephrites and fine/coarse-grained gabbros/norites to more evolved materials i.e. porphyritic trachyandesites, leucocratic trachytes and quartz-diorites. The basalts and gabbros are found all along the traverse of the rover, whereas the felsic rocks are located before the Kimberley formation, i.e. close to the Peace Vallis alluvial fan deposits. This suggests that these alkali rocks have been transported by fluvial activity and could come from the Northern rim of the crater, and may correspond to deeper strata buried under basaltic regolith (Sautter et al., 2015). Some of the basaltic igneous rocks are surprisingly enriched in iron, presenting low Mg# similar to the nakhlite parental melt that cannot be produced by direct melting of the Dreibus and Wanke (1986) martian primitive mantle. The basaltic rocks at Gale are thus different from Gusev basalts. They could originate from different mantle reservoirs

  12. Mars Sample Return: The Next Step Required to Revolutionize Knowledge of Martian Geological and Climatological History

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, D. W.

    2012-01-01

    The capability of scientific instrumentation flown on planetary orbiters and landers has made great advances since the signature Viking mission of the seventies. At some point, however, the science return from orbital remote sensing, and even in situ measurements, becomes incremental, rather than revolutionary. This is primarily caused by the low spatial resolution of such measurements, even for landed instrumentation, the incomplete mineralogical record derived from such measurements, the inability to do the detailed textural, mineralogical and compositional characterization needed to demonstrate equilibrium or reaction paths, and the lack of chronological characterization. For the foreseeable future, flight instruments will suffer from this limitation. In order to make the next revolutionary breakthrough in understanding the early geological and climatological history of Mars, samples must be available for interrogation using the full panoply of laboratory-housed analytical instrumentation. Laboratory studies of samples allow for determination of parageneses of rocks through microscopic identification of mineral assemblages, evaluation of equilibrium through electron microbeam analyses of mineral compositions and structures, determination of formation temperatures through secondary ion or thermal ionization mass spectrometry (SIMS or TIMS) analyses of stable isotope compositions. Such details are poorly constrained by orbital data (e.g. phyllosilicate formation at Mawrth Vallis), and incompletely described by in situ measurements (e.g. genesis of Burns formation sediments at Meridiani Planum). Laboratory studies can determine formation, metamorphism and/or alteration ages of samples through SIMS or TIMS of radiogenic isotope systems; a capability well-beyond flight instrumentation. Ideally, sample return should be from a location first scouted by landers such that fairly mature hypotheses have been formulated that can be tested. However, samples from clastic

  13. Chemical models for martian weathering profiles: Insights into formation of layered phyllosilicate and sulfate deposits

    NASA Astrophysics Data System (ADS)

    Zolotov, Mikhail Yu.; Mironenko, Mikhail V.

    2016-09-01

    Numerical chemical models for water-basalt interaction have been used to constrain the formation of stratified mineralogical sequences of Noachian clay-bearing rocks exposed in the Mawrth Vallis region and in other places on cratered martian highlands. The numerical approaches are based on calculations of water-rock type chemical equilibria and models which include rates of mineral dissolution. Results show that the observed clay-bearing sequences could have formed through downward percolation and neutralization of acidic H2SO4-HCl solutions. A formation of weathering profiles by slightly acidic fluids equilibrated with current atmospheric CO2 requires large volumes of water and is inconsistent with observations. Weathering by solutions equilibrated with putative dense CO2 atmospheres leads to consumption of CO2 to abundant carbonates which are not observed in clay stratigraphies. Weathering by H2SO4-HCl solutions leads to formation of amorphous silica, Al-rich clays, ferric oxides/oxyhydroxides, and minor titanium oxide and alunite at the top of weathering profiles. Mg-Fe phyllosilicates, Ca sulfates, zeolites, and minor carbonates precipitate from neutral and alkaline solutions at depth. Acidic weathering causes leaching of Na, Mg, and Ca from upper layers and accumulation of Mg-Na-Ca sulfate-chloride solutions at depth. Neutral MgSO4 type solutions dominate in middle parts of weathering profiles and could occur in deeper layers owing to incomplete alteration of Ca minerals and a limited trapping of Ca to sulfates. Although salts are not abundant in the Noachian geological formations, the results suggest the formation of Noachian salty solutions and their accumulation at depth. A partial freezing and migration of alteration solutions could have separated sulfate-rich compositions from low-temperature chloride brines and contributed to the observed diversity of salt deposits. A Hesperian remobilization and release of subsurface MgSO4 type solutions into newly

  14. Debris-flow origin for the Simud/Tiu deposit on Mars

    USGS Publications Warehouse

    Tanaka, K.L.

    1999-01-01

    A late Hesperian smooth plains deposit on Mars interpreted as a debris flow extends more than 2000 km from Hydraotes Chaos, through Simud and Tiu Valles, and into Chryse Planitia. The Simud/Tiu deposit widens out to >1000 km and embays streamlined landforms and knobs made up of sedimentary and perhaps volcanic deposits that were carved by earlier channeling activity. Morphologic features of the Simud/Tiu deposit observed in Viking and Pathfinder images are generally consistent with a debris-flow origin, but some of the deposit's salient features are not readily explained by catastrophic flooding or ice flow. Internal depressions appear to be bounded by linear scarps along flow margins where differential shearing may have occurred and in areas where flow spreading may have produced zones of extensional breakup and thinning within the flow. Possible flow lobes within the deposit may have formed by successive flow surges within the flow unit. The Pathfinder landing site is on the Simud/Tiu deposit, and the observations there are consistent with debris flow. The low, longitudinal ridges at the site may have formed by clast interactions as the flow ground to a halt. Imbricated, planar rocks on the ridges, such as in the Rock Garden, also may have been emplaced by debris or ice flow. However, stream energy calculations at Ares Vallis and channel geology indicate that flooding probably was incapable of emplacing the meter-size boulders observed at the Pathfinder site. Dewatering of pressurized zones in the debris flow or underlying material may be responsible for mud eruptions that formed a couple of patches of low pancakelike shields up to 5 km in diameter and for probable water flows that formed two small rille channels a few kilometers long. Local irregular grooves may be cracks that resulted from later desiccation and contraction of the flow material. The debris-flow unit apparently coalesced from outflows of water-fluidized debris originating from beneath chaotic and

  15. Abstracts of the Annual Meeting of Planetary Geologic Mappers, Flagstaff, AZ, 2010

    NASA Technical Reports Server (NTRS)

    Bleamaster, Leslie F., III (Editor); Tanaka, Kenneth L. (Editor); Kelley, Michael S. (Editor)

    2010-01-01

    Topics covered include: Detailed Analysis of the Intra-Ejecta Dark Plains of Caloris Basin, Mercury; The Formation and Evolution of Tessera and Insights into the Beginning of Recorded History on Venus: Geology of the Fortuna Tessera Quadrangle (V-2); Geologic Map of the Snegurochka Planitia Quadrangle (V-1): Implications for the Volcanic History of the North Polar Region of Venus; Geological Map of the Fredegonade (V-57) Quadrangle, Venus: Status Report; Geologic Mapping of V-19; Geology of the Lachesis Tessera Quadrangle (V-18), Venus; Comparison of Mapping Tessera Terrain in the Phoebe Regio (V-41) and Tellus Tessera (V-10) Quadrangles; Geologic Mapping of the Devana Chasma (V-29) Quadrangle, Venus; Geologic Mapping of the Aristarchus Plateau Region on the Moon; Geologic Mapping of the Lunar South Pole Quadrangle (LQ-30); The Pilot Lunar Geologic Mapping Project: Summary Results and Recommendations from the Copernicus Quadrangle; Geologic Mapping of the Nili Fossae Region of Mars: MTM Quadrangles 20287, 20282, 25287, 25282, 30287, and 30282; Geologic Mapping of the Mawrth Vallis Region, Mars: MTM Quadrangles 25022, 25017, 25012, 20022, 20017, and 20012; Evidence for an Ancient Buried Landscape on the NW Rim of Hellas Basin, Mars; New Geologic Map of the Argyre Region of Mars: Deciphering the Geologic History Through Mars Global Surveyor, Mars Odyssey, and Mars Express Data; Geologic Mapping in the Hesperia Planum Region of Mars; Geologic Mapping of the Meridiani Region of Mars; Geologic Mapping in Southern Margaritifer Terra; Geology of -30247, -35247, and -40247 Quadrangles, Southern Hesperia Planum, Mars; The Interaction of Impact Melt, Impact-Derived Sediment, and Volatiles at Crater Tooting, Mars; Geologic Map of the Olympia Cavi Region of Mars (MTM 85200): A Summary of Tactical Approaches; Geology of the Terra Cimmeria-Utopia Planitia Highland Lowland Transitional Zone: Final Technical Approach and Scientific Results; Geology of Libya Montes and the

  16. Cholinergically-induced changes in outward currents in hair cells isolated from the semicircular canal of the frog.

    PubMed

    Housley, G D; Norris, C H; Guth, P S

    1990-01-01

    Two cholinergically-induced modulations of membrane conductances have been identified in hair cells isolated from the crista ampullaris of the leopard frog (Rana pipiens), using the whole cell recording configuration of the patch clamp technique. Of 56 crista hair cells tested, 28 showed drug-induced changes in membrane current or membrane potential which were repeatable and could be reversed with washout of drug. The predominant effect (observed in 20 hair cells) of acetylcholine (Ach, 100 microM) to 1mM) or carbachol (1 microM to 50 microM) applied to these hair cells was the reduction of an outward current corresponding to a change in conductance of approximately -0.22 nS. This action by Ach on hair cells has been inferred from previous studies of afferent fiber discharge which reported an increase in firing rate with stimulation of efferent fibers or exogenous application of cholinomimetics (Bernard et al., 1985; Valli et al., 1986; Guth et al., 1986; Norris et al., 1988a). The Ach-induced reduction in outward current was associated with a depolarization of the zero-current membrane potential by approximately +2.5 mV. In a total of 8 hair cells, an Ach-induced reversible increase in outward current was recorded. Changes in conductance were approximately +0.13 nS and were associated with a hyperpolarization of the zero-current membrane potential by approximately -2.2 mV. This current increase is likely to be responsible for the inhibitory post-synaptic potentials (IPSPs) which have previously been recorded intracellularly from acoustico-lateralis hair cells during stimulation of the efferent innervation (Flock and Russell, 1976; Ashmore and Russell, 1982; Art et al., 1984, 1985). Of the remaining 28 hair cells, six cells failed to exhibit any change in membrane conductance or membrane potential in the presence of cholinomimetics while an additional 15 cells exhibited decreases, and 7 cells exhibited increases in outward conductance, during application of Ach or

  17. Potential ExoMars Rover Landing Sites: Aram Dorsam (previously known as Oxia Palus) and Hypanis Delta

    NASA Astrophysics Data System (ADS)

    Sefton-Nash, E.; Balme, M. R.; Grindrod, P. M.; Gupta, S.; Fawdon, P.; Muller, J. P.; Michalski, J. R.

    2014-12-01

    The search for life on Mars is a cornerstone of international solar system exploration. In 2018, the European Space agency will launch the ExoMars Rover to further this. The key science objectives of the ExoMars Rover are to: 1) search for signs of past and present life on Mars; 2) investigate the water/geochemical environment as a function of depth in the shallow subsurface; and 3) to characterise the surface environment. ExoMars will drill into the sub-surface to look for indicators of past life using a variety of complementary techniques, including assessment of morphology (potential fossil organisms), mineralogy (past environments) and a search for organic molecules and their chirality (biomarkers). The choice of landing site is vital if the objectives are to be met. The landing site must: (i) be ancient (≥3.6 Ga); (ii) show abundant morphological and mineral evidence for long-term, or frequently reoccurring, aqueous activity; (iii) include numerous sedimentary outcrops that (iv) are distributed over the landing region (the typical Rover traverse range is a few km, but ellipse size is ~ 100 by 15 km). Various 'engineering constraints' also apply, including: (i) latitude limited to 5º S to 25º N; (ii) maximum altitude of the landing site 2 km below Mars's datum; and (iii) few steep slopes within the ellipse. In March 2014, the first ExoMars Landing Site Selection Workshop was held, during which about ten different landing sites were presented and discussed. At the end of the workshop a poll of the workshop participants highlighted four sites as highest priority: Mawrth Vallis, Oxia Planum, Oxia Palus and Hypanis Delta. Of these, our team led proposals for the Oxia Palus and Hypanis Delta sites. The Oxia Palus site has since been renamed "Aram Dorsum" - the name the IAU designated to the inverted channel system that is the most prominent feature of the site. This is inferred to be the remnants of a long-lived, widespread alluvial system that was buried and

  18. The Northwestern Slope Valleys Region, Mars: A Prime Target for the Future Exploration of Mars

    NASA Astrophysics Data System (ADS)

    Dohm, J. M.; Ferris, J. C.; Anderson, R. C.; Baker, V. R.; Hare, T. M.; Mahaney, W. C.

    2002-12-01

    at least three distinct paleohydrologic regimes: Noachian-Early Hesperian NSVs flooding (~108 - 1010 m3/sec), Late Hesperian-Early Amazonian Mangala Valles flooding (~107 m3/sec), Amazonian sapping channel formation (~103 m3/sec), and recent groundwater seeps (<102 m3/sec), all of which expose deposits for in-situ study and sample return. Terrestrial analogs include: (1) Wet Beaver Creek, Arizona, which reveals intriguing geologic, hydrogeologic, and geomorphic similarities to a well-developed martian sapping channel, Abus Vallis, and (2) the Gray Mountain FIDO rover test site, which records diverse geological terrains similar to what might be encountered at the proposed NSVs prime target site.

  19. Geologic map of the Barrymore Quadrangle (V-59), Venus

    USGS Publications Warehouse

    Johnson, Jeffrey R.; Komatsu, Goro; Baker, Victor R.

    1999-01-01

    The Barrymore quadrangle (V–59) is a predominantly ridged plains region south of Imdr Regio, incorporating portions of Helen, Nuptadi, and Nsomeka Planitiae. The map area extends from lat 50°–75° S. and long 180°–240°, with nearly 70% coverage by cycle 1 synthetic aperture radar (SAR) images (left-look, incidence angles 16°–23°) and complete coverage by cycle 2 images (right-look, incidence angles 20°–25°) (fig. 1). The majority of the map area is covered by regional plains material that may either be smooth or deformed by wrinkle ridges or ridge belts of variable spacing. The difference in elevation between highest and lowest points in the map area is about 2.3 km. A north-south-oriented, 1,375-km linear ridge belt named “Saule Dorsa” is in the center of the region. The southern tip of this belt is intersected by a stratigraphically complicated, east-west-trending intermittent series of disrupted material, arcuate depressions and rises, regional plains, and volcanic centers. This region (hereafter referred to as the “east-west disrupted zone”) lies within a belt between 63°–67° S. extending from Kadlu Dorsa to Moombi Corona. A high concentration of canali-type channels (long sinuous lava channels that may contain subsidiary channels that branch off from the main channel [Baker and others, 1992; Komatsu and others, 1992]) occurs in Nsomeka Planitia. This includes Xulab Vallis and Citlalpul Valles, which form the eastern extent of a 3,000-km-long canali system (Komatsu and others, 1993). Three instances of canali bifurcation from north-south to east-west orientations occur in this region (fig. 2). Several large impact craters with fluidized ejecta blanket (FEB) outflows occur in the map area, along with some impact crater extended deposits (parabolas). The latter are mapped as surficial material using stipple patterns over the plains materials. These surficial deposits show variations in radar backscatter properties between cycle 1 and

  20. Valles Marineris and Chryse Outflow Channels

    NASA Image and Video Library

    1998-06-08

    connected channel floors and chaotic terrain and extend as far south as and connect to eastern Valles Marineris. Ares Vallis originates from discontinuous patches of chaotic terrain within large craters. In the Chryse basin the Ares channel forks; one branch continues northwest into central Chryse Planitia and the other extends north into eastern Chryse Planitia. http://photojournal.jpl.nasa.gov/catalog/PIA00426

  1. Assessment of Mars Pathfinder landing site predictions

    USGS Publications Warehouse

    Golombek, M.P.; Moore, H.J.; Haldemann, A.F.C.; Parker, T.J.; Schofield, J.T.

    1999-01-01

    Remote sensing data at scales of kilometers and an Earth analog were used to accurately predict the characteristics of the Mars Pathfinder landing site at a scale of meters. The surface surrounding the Mars Pathfinder lander in Ares Vallis appears consistent with orbital interpretations, namely, that it would be a rocky plain composed of materials deposited by catastrophic floods. The surface and observed maximum clast size appears similar to predictions based on an analogous surface of the Ephrata Fan in the Channeled Scabland of Washington state. The elevation of the site measured by relatively small footprint delay-Doppler radar is within 100 m of that determined by two-way ranging and Doppler tracking of the spacecraft. The nearly equal elevations of the Mars Pathfinder and Viking Lander 1 sites allowed a prediction of the atmospheric conditions with altitude (pressure, temperature, and winds) that were well within the entry, descent, and landing design margins. High-resolution (~38 m/pixel) Viking Orbiter 1 images showed a sparsely cratered surface with small knobs with relatively low slopes, consistent with observations of these features from the lander. Measured rock abundance is within 10% of that expected from Viking orbiter thermal observations and models. The fractional area covered by large, potentially hazardous rocks observed is similar to that estimated from model rock distributions based on data from the Viking landing sites, Earth analog sites, and total rock abundance. The bulk and fine-component thermal inertias measured from orbit are similar to those calculated from the observed rock size-frequency distribution. A simple radar echo model based on the reflectivity of the soil (estimated from its bulk density), and the measured fraction of area covered by rocks was used to approximate the quasi-specular and diffuse components of the Earth-based radar echos. Color and albedo orbiter data were used to predict the relatively dust free or unweathered

  2. The Paleoflood Record of the Upper Colorado River near Moab, Utah

    NASA Astrophysics Data System (ADS)

    Greenbaum, N.; Harden, T.; Baker, V. R.; Weisheit, J. S.; Cline, M. L.; Halevi, R.; Dohrenwend, J. C.

    2011-12-01

    the probable maximum flood (8300 m3s-1) and 24 floods exceeded 3400 m3s-1 (the 500-year flood) calculated for the Moab Vally.

  3. Planetary size critical to the preservation of primordial anorthosite-enriched continental crust and life potential

    NASA Astrophysics Data System (ADS)

    Dohm, J. M.; Maruyama, S.

    2016-12-01

    Primordial continental crust (PCC) of the Moon consists of anorthosite. Anorthosite has been discovered on the Martian surface as well, possibly of significant extent as on the Moon [1]. In the case of the Earth, the occurrence of anorthosite is observed to be limited in the geological record; however, lunar and Martian surface geology indicate that anorthosite may have been more universal on the Earth as PCC during the Hadean. We propose that differences in the presence of anorthosite-enriched PCC are due to planetary size. The reason why the PCC of Earth disappeared is explained by the strength and duration of mantle convection and plate tectonics, compared to the Moon and its relatively rapid cooling following the development of a magma ocean. We also theorize that Mars also retains its anorthosite-enriched PCC, which includes andesite and granite due to an early phase of plate tectonics that shut down prior to its complete destruction (roughly 3.93 Ga) as a result of its relatively small mass and rapid cooling [2]. Growing evidence of this includes anorthosite identified in Hellas rim materials [1], exposures of possible granite in more ancient terrain of Noachis Terra [3], and alluvial-fan materials of Peace Vallis in Gale crater, which have been interpreted to be representative of an ancient felsic crust [4], and in particular > 4.0 Ga Terra Cimmeria crustal basement exposed by the Gale impact [5]. Nutrient-enriched PCC is essential in determining the fate of the planet to be habitable or not. Mars has elevated habitability potential because of its PCC that was once exposed above an ocean that interacted with a relatively thick atmosphere through Sun-driven hydrological circulation, known as Habitable-Trinity conditions [6]. At this conference, we will discuss the significance of planetary size on both the preservation of anorthosite-enriched PCC on rocky planets and habitability potential, and why the Martian PCC will be a key target of exploration. [1

  4. Streamlined Islands in Ares Valles

    NASA Technical Reports Server (NTRS)

    2002-01-01

    . It all depends on your hypothesis. Like the streamlined islands, the current-like flutes are parallel to the direction of flow, indicating that the water flow was turbulent and probably quite fast, which is consistent with the hypothesis that catastrophic floods broke forth in this region, known as Ares Vallis. Ares Vallis is the region where Pathfinder landed to help understand the possible history of water on Mars. Geologists want to understand not only if there was a catastrophic flood, but why it happened. Both orbiters and landers can add to the information on hand, but some Earth examples might provide clues as well. On our planet, some glacial valleys have had major catastrophic floods that were caused by the sudden outburst and drainage of glacial lakes. The Channeled Scabland in Washington state is great Earthly example of a place where the sudden failure of a glacier ice dam spewed out water, leaving a system of large, dry channels with flutes similar to the ones seen in this image. Did something similar happen to cause this outburst on Mars? Hopefully, future studies of THEMIS and other images will help us understand the answer.

  5. Removal of atmospheric features in near infrared spectra by means of principal component analysis and target transformation on Mars: I. Method

    NASA Astrophysics Data System (ADS)

    Geminale, A.; Grassi, D.; Altieri, F.; Serventi, G.; Carli, C.; Carrozzo, F. G.; Sgavetti, M.; Orosei, R.; D'Aversa, E.; Bellucci, G.; Frigeri, A.

    2015-06-01

    The aim of this work is to extract the surface contribution in the martian visible/near-infrared spectra removing the atmospheric components by means of Principal Component Analysis (PCA) and target transformation (TT). The developed technique is suitable for separating spectral components in a data set large enough to enable an effective usage of statistical methods, in support to the more common approaches to remove the gaseous component. In this context, a key role is played by the estimation, from the spectral population, of the covariance matrix that describes the statistical correlation of the signal among different points in the spectrum. As a general rule, the covariance matrix becomes more and more meaningful increasing the size of initial population, justifying therefore the importance of sizable datasets. Data collected by imaging spectrometers, such as the OMEGA (Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité) instrument on board the ESA mission Mars Express (MEx), are particularly suitable for this purpose since it includes in the same session of observation a large number of spectra with different content of aerosols, gases and mineralogy. The methodology presented in this work has been first validated using a simulated dataset of spectra to evaluate its accuracy. Then, it has been applied to the analysis of OMEGA sessions over Nili Fossae and Mawrth Vallis regions, which have been already widely studied because of the presence of hydrated minerals. These minerals are key components of the surface to investigate the presence of liquid water flowing on the martian surface in the Noachian period. Moreover, since a correction for the atmospheric aerosols (dust) component is also applied to these observations, the present work is able to completely remove the atmospheric contribution from the analysed spectra. Once the surface reflectance, free from atmospheric contributions, has been obtained, the Modified Gaussian Model (MGM) has

  6. Arecibo radar imagery of Mars: II. Chryse-Xanthe, polar caps, and other regions

    NASA Astrophysics Data System (ADS)

    Harmon, John K.; Nolan, Michael C.

    2017-01-01

    We conclude our radar imaging survey of Mars, which maps spatial variations in depolarized radar reflectivity using Arecibo S-band (λ12.6 cm) observations from 2005-2012. Whereas our earlier paper (Harmon et al., 2012, Arecibo radar imagery of Mars: the major volcanic provinces. Icarus 220, 990-1030) covered the volcanic regions of Tharsis, Elysium, and Amazonis, this paper includes non-volcanic regions where hydrologic and impact processes can be the dominant resurfacing agents affecting radar backscatter. Many of the more prominent and interesting radar-bright features outside the major volcanic provinces are located in and around Chryse Planitia and Xanthe Terra. These features are identified with: a basin in northeast Lunae Planum containing the combined deposits from Maja Vallis and Ganges Catena outflows; channel outwash plains in western and southern Chryse basin; plateaus bordering chasma/chaos zones, where surface modification may have resulted from hydrologic action associated with incipient chaos formation; and some bright-ejecta craters in Chryse basin, of a type otherwise rare on Mars. Dark-halo craters have also been identified in Chryse and elsewhere that are similar to those seen in the volcanic provinces. Although the cratered highlands are relatively radar-bland, they do exhibit some bright depolarized features; these include eroded crater rims, several unusual ejecta flows and impact melts, and terrain-softened plains. The rims of large impact basins (Hellas, Argyre, Isidis) show a variety of radar-bright features provisionally identified with massif slopes, erosion sediments, eroded pyroclastics, impact melts, and glacial deposits. The interiors of these basins are largely radar-dark, which is consistent with coverage by rock-free sediments. Tempe Terra and Acheron Fossae show bright features possibly associated with rift volcanism or eroded tectonic structures, and northwest Tempe Terra shows one very bright feature associated with glacial or

  7. Improving determination of the Martian rotation parameters through the synergy between LaRa and RISE radioscience experiments

    NASA Astrophysics Data System (ADS)

    Le Maistre, S.; Péters, M. J.; Yseboodt, M.; Dehant, V. M. A.

    2017-12-01

    estimates obtained from RISE alone.In addition, because the two candidate landing sites of ExoMars are higher in latitude (18.20°N for Oxia Planum, 22°N for Mawrth Vallis) than InSight (4°N), we could estimate for the very first time the Chandler Wobble component of the polar motion using LaRa (Le Maistre et al., 2012), which is also powerful to constrain Mars interior and atmospheric models.

  8. Characterizing the Phyllosilicates and Amorphous Phases Found by MSL Using Laboratory XRD and EGA Measurements of Natural and Synthetic Materials

    NASA Technical Reports Server (NTRS)

    Rampe, Elizabeth B.; Morris, Richard V.; Chipera, Steve; Bish, David L.; Bristow, Thomas; Archer, Paul Douglas; Blake, David; Achilles, Cherie; Ming, Douglas W.; Vaniman, David; hide

    2013-01-01

    The Curiosity Rover landed on the Peace Vallis alluvial fan in Gale crater on August 5, 2012. A primary mission science objective is to search for past habitable environments, and, in particular, to assess the role of past water. Identifying the minerals and mineraloids that result from aqueous alteration at Gale crater is essential for understanding past aqueous processes at the MSL landing site and hence for interpreting the site's potential habitability. X-ray diffraction (XRD) data from the CheMin instrument and evolved gas analyses (EGA) from the SAM instrument have helped the MSL science team identify phases that resulted from aqueous processes: phyllosilicates and amorphous phases were measure in two drill samples (John Klein and Cumberland) obtained from the Sheepbed Member, Yellowknife Bay Fm., which is believed to represent a fluvial-lacustrine environment. A third set of analyses was obtained from scoop samples from the Rocknest sand shadow. Chemical data from the APXS instrument have helped constrain the chemical compositions of these secondary phases and suggest that the phyllosilicate component is Mg-enriched and the amorphous component is Fe-enriched, relatively Si-poor, and S- and H-bearing. To refine the phyllosilicate and amorphous components in the samples measured by MSL, we measured XRD and EGA data for a variety of relevant natural terrestrial phyllosilicates and synthetic mineraloids in laboratory testbeds of the CheMin and SAM instruments. Specifically, Mg-saturated smectites and vermiculites were measured with XRD at low relative humidity to understand the behavior of the 001 reflections under Mars-like conditions. Our laboratory XRD measurements suggest that interlayer cation composition affects the hydration state of swelling clays at low RH and, thus, the 001 peak positions. XRD patterns of synthetic amorphous materials, including allophane, ferrihydrite, and hisingerite were used in full-pattern fitting (FULLPAT) models to help

  9. The First X-ray Diffraction Patterns of Clay Minerals from Gale Crater

    NASA Astrophysics Data System (ADS)

    Bristow, T.; Blake, D.; Bish, D. L.; Vaniman, D.; Ming, D. W.; Morris, R. V.; Chipera, S.; Rampe, E. B.; Farmer, J. D.; Treiman, A. H.; Downs, R.; Morrison, S.; Achilles, C.; Des Marais, D. J.; Crisp, J. A.; Sarrazin, P.; Morookian, J.; Grotzinger, J. P.; Team, M.

    2013-12-01

    The Mars Science Laboratory (MSL) Rover, Curiosity spent ~150 sols at Yellowknife Bay (YKB) studying a section of fluvio-lacustrine sedimentary rocks (with potential indications of volcanic influence), informally known as the Yellowknife Bay formation. YKB lies in a distal region of the Peace Vallis alluvial fan, which extends from the northern rim of Gale Crater toward the dune field at the base of Mt Sharp. Sedimentological and stratigraphic observations are consistent with the Yellowknife Bay formation being part of a distal fan deposit, which could be as young as middle Hesperian to even early Amazonian in age (~3.5 to 2.5 Ga). The Yellowknife Bay formation hosts a unit of mudstone called the Sheepbed member. Curiosity obtained powdered rock samples from two drill holes in the Sheepbed Member, named John Klein and Cumberland, and delivered them to instruments in Curiosity. Data from CheMin, a combined X-ray diffraction (XRD)/X-ray fluorescence instrument (XRF), has allowed detailed mineralogical analysis of mudstone powders revealing a clay mineral component of ~20 wt.% in each sample. The clay minerals are important indicators of paleoenvironmental conditions and sensitive recorders of post-depositional alteration processes. The XRD pattern of John Klein reveals a 02l band consistent with a trioctahedral phyllosilicate. A broad peak at ~10A with a slight inflexion at ~12A indicates the presence of 2:1 type clay minerals in the John Klein sample. The trioctahedral nature of the clay minerals, breadth of the basal reflection, and presence of a minor component with larger basal spacing suggests that John Klein contains a trioctahedral smectite (probably saponite), whose interlayer is largely collapsed because of the low-humidity conditions. The XRD patterns show no evidence of corrensite (mixed-layer chlorite/smectite) or chlorite, which are typical diagenetic products of trioctahedral smectites when subjected to burial and heating >60°C in the presence of water

  10. Anoxic and Oxic Oxidation of Rocks Containing Fe(II)Mg-Silicates and Fe(II)-Monosulfides as Source of Fe(III)-Minerals and Hydrogen. Geobiotropy.

    NASA Astrophysics Data System (ADS)

    Bassez, Marie-Paule

    2017-12-01

    ferric trihydroxide, goethite/lepidocrocite and hematite and also to sulfates, and at 250 °C mainly to magnetite instead of pyrite, associated to the same ferric oxides/hydroxides and sulfates. Some examples of geological terrains, such as Mawrth Vallis on Mars, the Tagish Lake meteorite and hydrothermal venting fields, where hydrolysis/oxidation of ferromagnesian silicates and iron(II)-monosulfides may occur, are discussed. Considering the evolution of rocks during their interaction with water, in the absence of oxygen and in radiolyzed water, with hydrothermal release of H2 and the plausible associated formation of components of life, geobiotropic signatures are proposed. They are mainly Fe(III)-phyllosilicates, magnetite, ferric trihydroxide, goethite/lepidocrocite, hematite, but not pyrite.

  11. Mars Science Laboratory: Results From Bradbury Landing to Glenelg

    NASA Astrophysics Data System (ADS)

    Grotzinger, John; Blake, Dave; Crisp, Joy; Edgett, Ken; Gellert, Ralf; Gomez Elvira, Javier; Hassler, Don; Mahaffy, Paul; Malin, Mike; Mitrofanov, Igor; Meyer, Michael; Vasavada, Ashwin; Wiens, Roger; MSL Science Team

    2013-04-01

    The Mars Science Laboratory rover, Curiosity, analyzed rocks, soils, and the atmosphere between Bradbury Landing and the contact with a light-toned, fractured , high-thermal inertia unit ~500 meters to the east ("Glenelg"). A number of in-place outcrops were encountered along this traverse that allows a simple stratigraphy to be con-structed. A variety of siliciclastic sedimentary rocks are present in the section, possibly also including minor basaltic volcanics. At several localities en route to Glenelg, Curiosity observed conglomeratic bedrock containing rounded pebbles ranging in size from 5-40 mm, forming beds at least 5 cm thick with locally well-developed planar stratification; this, plus grain-supported and imbricated clast fabrics suggest transport in aqueous flows with depths of 0.1-0.8 m, and velocities of 14-63 cm/sec. These conglomerates were likely derived from the Gale crater rim and transported down the Peace Vallis channel network; ChemCam data suggest the presence of feldspar and basaltic composition rock fragments as pebbles. APXS and ChemCam data show the out-of-place rock, "Jake Matijevic", to have an evolved, alkaline composi-tion similar to nepheline-normative muegerites, and suggestive of high pressure partial melting of the mantle. Other, stratigraphically in-place rocks show basanitic composition, with high K2O, low SiO2, and high FeO. Between Sols 56 and 110 Curiosity studied the "Rocknest" eolian deposit which was selected for scooping and eventual delivery to CheMin and SAM. The APXS composition of this deposit is consistent with average Mars soils encountered by previous missions (SO3 + Cl ~6 wt.%). Scooped samples delivered to CheMin reveal the presence of forsterite, pigeonite, augite, plagioclase, and several trace minerals including quartz, anhydrite, magnetite, hematite and illmenite. SAM analysis of the scooped soil yielded four different Evolved Gas Analysis (EGA) experiments depending on the temperature at which evolved gases

  12. Anoxic and Oxic Oxidation of Rocks Containing Fe(II)Mg-Silicates and Fe(II)-Monosulfides as Source of Fe(III)-Minerals and Hydrogen. Geobiotropy.

    PubMed

    Bassez, Marie-Paule

    2017-12-01

    /hydroxides such as ferric trihydroxide, goethite/lepidocrocite and hematite and also to sulfates, and at 250 °C mainly to magnetite instead of pyrite, associated to the same ferric oxides/hydroxides and sulfates. Some examples of geological terrains, such as Mawrth Vallis on Mars, the Tagish Lake meteorite and hydrothermal venting fields, where hydrolysis/oxidation of ferromagnesian silicates and iron(II)-monosulfides may occur, are discussed. Considering the evolution of rocks during their interaction with water, in the absence of oxygen and in radiolyzed water, with hydrothermal release of H 2 and the plausible associated formation of components of life, geobiotropic signatures are proposed. They are mainly Fe(III)-phyllosilicates, magnetite, ferric trihydroxide, goethite/lepidocrocite, hematite, but not pyrite.

  13. Phyllosilcates in the Knob Fields around Ariadnes Colles on Mars: Stratigraphy, Mineralogy and Morphology

    NASA Astrophysics Data System (ADS)

    Wendt, L.; Bishop, J. L.; Neukum, G.

    2012-04-01

    The region between Terra Cimmeria and Terra Sirenum contains several fields of enigmatic knobs, in-cluding Ariadnes Colles, Atlantis Chaos and Gorgo-num Chaos. They have been mapped as Hesperian or Amazonian units [1,2] and are located within the shoreline of the Eridania Lake, which might have formed Ma'adim Vallis [3]. The knob fields contain Mg/Fe-rich and locally Al-rich phyllosilicates [5,6, this study]. Following the stratigraphic placement by [1,2], the knobs are younger than the Noachian, in a possible disagreement to [4]. The region also features chloride deposits [7] and valley networks younger than the Hesperian ridged plains (Hr unit [1,2]), named Mid-Latitude Valleys (MLV) by [8], and has been proposed as an MSL landing site by [9]. The knob fields have been mapped by [10] as "surface type 4" of a possible airfall deposit informally named "Electris deposit", which covers the Hesperian ridged plains and cratered uplands. A recent study by [6], suggested that the knob fields are not part of, but postdate the "Electris deposit", yet possibly contain reworked "Electris" material. Our geological mapping shows that the knob fields are indeed one morphological expression consistent with the "Electris deposit" model [10]. However, the "Electris" deposit does not stratigraphically overlay the Hesperian ridged plains (Hr unit) and is eroded back to the level of the ridged plains, as proposed by [6,10]. Instead, the "Electris" deposit, including the knob fields, is covered or embayed by the ridged plains, and thus is older. This results in a late Noachian age for the "Electris deposit", in agreement with [11]. This also reconciles the apparent contradiction of the stratigraphy suggested by [1,2,6,10] to [4], as the clays would then indeed have formed in the "phyllosian" period, as "sedimentary clays" of [12]. Wide valley networks cut into the "Electris" deposit and may have filled the Eridania lake. The knob fields and clays within are observed at varying total

  14. Formation and disruption of aquifers in southwestern Chryse Planitia, Mars

    USGS Publications Warehouse

    Rodriguez, J.A.P.; Tanaka, K.L.; Kargel, J.S.; Dohm, J.M.; Kuzmin, R.; Fairen, A.G.; Sasaki, S.; Komatsu, G.; Schulze-Makuch, D.; Jianguo, Y.

    2007-01-01

    We present geologic evidence suggesting that after the development of Mars' cryolithosphere, the formation of aquifers in southwestern Chryse Planitia and their subsequent disruption led to extensive regional resurfacing during the Late Hesperian, and perhaps even during the Amazonian. In our model, these aquifers formed preferentially along thrust faults associated with wrinkle ridges, as well as along fault systems peripheral to impact craters. The characteristics of degraded wrinkle ridges and impact craters in southwestern Chryse Planitia indicate a profound role of subsurface volatiles and especially liquid water in the upper crust (the upper one hundred to a few thousands of meters). Like lunar wrinkle ridges, the martian ones are presumed to mark the surface extensions of thrust faults, but in our study area the wrinkle ridges are heavily modified. Wrinkle ridges and nearby plains have locally undergone collapse, and in other areas they are associated with domical intrusions we interpret as mud volcanoes and mud diapirs. In at least one instance, a sinuous valley emanates from a modified wrinkle ridge, further indicating hydrological influences on these thrust-fault-controlled features. A key must be the formation of volatile-rich crust. Primary crustal formation and differentiation incorporated juvenile volatiles into the global crust, but the crustal record here was then strongly modified by the giant Chryse impact. The decipherable rock record here begins with the Chryse impact and continues with the resulting basin's erosion and infilling, which includes outflow channel activity. We propose that in Simud Vallis surface flow dissection into the base of the cryolithosphere-produced zones where water infiltrated and migrated along SW-dipping strata deformed by the Chryse impact, thereby forming an extensive aquifer in southwestern Chryse Planitia. In this region, compressive stresses produced by the rise of Tharsis led to the formation of wrinkle ridges

  15. Paleoenvironmental Implications of Clay Minerals at Yellowknife Bay, Gale Crater, Mars

    NASA Technical Reports Server (NTRS)

    Bristow, Thomas F.; Blake, David F.

    2014-01-01

    The Mars Science Laboratory (MSL) Rover, Curiosity spent approx 150 sols at Yellowknife Bay (YKB) studying a section of fluvio-lacustrine sedimentary rocks (with potential indications of volcanic influence), informally known as the Yellowknife Bay formation. YKB lies in a distal region of the Peace Vallis alluvial fan, which extends from the northern rim of Gale Crater toward the dune field at the base of Mt Sharp. Sedimentological and stratigraphic observations are consistent with the Yellowknife Bay formation being part of a distal fan deposit, which could be as young as middle Hesperian to even early Amazonian in age (approx. 3.5 to 2.5 Ga). The Yellowknife Bay formation hosts a unit of mudstone called the Sheepbed member. Curiosity obtained powdered rock samples from two drill holes in the Sheepbed Member, named John Klein and Cumberland, and delivered them to instruments in Curiosity. Data from CheMin, a combined X-ray diffraction (XRD)/X-ray fluorescence instrument (XRF), has allowed detailed mineralogical analysis of mudstone powders revealing a clay mineral component of approx. 20 wt.% in each sample. The clay minerals are important indicators of paleoenvironmental conditions and sensitive recorders of post-depositional alteration processes. The XRD pattern of John Klein reveals a 02l band consistent with a trioctahedral phyllosilicate. A broad peak at approx. 10A with a slight inflexion at approx. 12A indicates the presence of 2:1 type clay minerals in the John Klein sample. The trioctahedral nature of the clay minerals, breadth of the basal reflection, and presence of a minor component with larger basal spacing suggests that John Klein contains a trioctahedral smectite (probably saponite), whose interlayer is largely collapsed because of the low-humidity conditions. The XRD patterns show no evidence of corrensite (mixed-layer chlorite/smectite) or chlorite, which are typical diagenetic products of trioctahedral smectites when subjected to burial and

  16. Analysis of Ice-Related Intra-Crater Facies in Promethei Terra, Mars

    NASA Astrophysics Data System (ADS)

    Orgel, Csilla; Kereszturi, Ákos; van Gasselt, Stephan

    2014-05-01

    On Mars ice-related landforms have been identified at mid-latitudes between 30° and 50° in both hemispheres including the areas of Tempe Terra, Deuteronilus-Protonilus Mensae, Phlegra Montes and the rims of the southern-hemispheric impact basins Argyre and Hellas [1-7]. Our study area - informally termed hourglass-shaped crater [8] - is located near Reull Vallis on the eastern rim of the Hellas impact basin (39.0°S, 102.8°E). Impact-crater infill was described as debris-covered piedmont-type glacier [8] based on analysis of High Resolution Stereo Camera (HRSC) data, and implies a glacial origin with precipitation of ice during higher obliquity phases. Recent, higher-resolution image data such as data of the High Resolution Imaging Science Experiment (HiRISE) and the Context Imager (CTX) provide a more detailed picture of the lateral distribution of different small-scale surface features indicative of periglacial and/or glacial origin. The aim of this study is to identify qualitative and quantitative characteristics of these ice-related landforms and to separate sources of water ice and related processes. Initial age determinations based on impact-crater size-frequency statistics indicate an age of 3.4 Gyr for the impact-crater and an age of approximately 75 Myr for the infill [8]. In order to identify a possible sequence of surface-feature evolution we calculated the age distribution of four major surface units which span ages ages between 1-47 Myr. Along with detailed age information and a separation of different processes at this confined type location of Mars young-Amazonian landscape evolution and potential cyclic signals are being reconstructed to constrain climate evolution. Carr, M. H. & Schaber, G. G. 1977: Martian permafrost features.- J. Geophys. Res. 82, 4039-4054. Squyres, S. W. 1978: Martian fretted terrain: flow of erosional debris.- Icarus 34, 600-613. Squyres, S. W. 1979: The distribution of lobate debris aprons and similar flows on Mars.- J

  17. The P1N-PISPO trans-Frame Gene of Sweet Potato Feathery Mottle Potyvirus Is Produced during Virus Infection and Functions as an RNA Silencing Suppressor

    PubMed Central

    Mingot, Ares; Valli, Adrián; Rodamilans, Bernardo; San León, David; Baulcombe, David C.; García, Juan Antonio

    2016-01-01

    ABSTRACT The positive-sense RNA genome of Sweet potato feathery mottle virus (SPFMV) (genus Potyvirus, family Potyviridae) contains a large open reading frame (ORF) of 3,494 codons translatable as a polyprotein and two embedded shorter ORFs in the −1 frame: PISPO, of 230 codons, and PIPO, of 66 codons, located in the P1 and P3 regions, respectively. PISPO is specific to some sweet potato-infecting potyviruses, while PIPO is present in all potyvirids. In SPFMV these two extra ORFs are preceded by conserved G2A6 motifs. We have shown recently that a polymerase slippage mechanism at these sites could produce transcripts bringing these ORFs in frame with the upstream polyprotein, thus leading to P1N-PISPO and P3N-PIPO products (B. Rodamilans, A. Valli, A. Mingot, D. San Leon, D. B. Baulcombe, J. J. Lopez-Moya, and J.A. Garcia, J Virol 89:6965–6967, 2015, doi:10.1128/JVI.00337-15). Here, we demonstrate by liquid chromatography coupled to mass spectrometry that both P1 and P1N-PISPO are produced during viral infection and coexist in SPFMV-infected Ipomoea batatas plants. Interestingly, transient expression of SPFMV gene products coagroinfiltrated with a reporter gene in Nicotiana benthamiana revealed that P1N-PISPO acts as an RNA silencing suppressor, a role normally associated with HCPro in other potyviruses. Moreover, mutation of WG/GW motifs present in P1N-PISPO abolished its silencing suppression activity, suggesting that the function might require interaction with Argonaute components of the silencing machinery, as was shown for other viral suppressors. Altogether, our results reveal a further layer of complexity of the RNA silencing suppression activity within the Potyviridae family. IMPORTANCE Gene products of potyviruses include P1, HCPro, P3, 6K1, CI, 6K2, VPg/NIaPro, NIb, and CP, all derived from the proteolytic processing of a large polyprotein, and an additional P3N-PIPO product, with the PIPO segment encoded in a different frame within the P3 cistron. In

  18. The First X-ray Diffraction Patterns of Clay Minerals from Gale Crater

    NASA Technical Reports Server (NTRS)

    Bristow, Thomas; Blake, David; Bish, David L.; Vaniman, David; Ming, Douglas W.; Morris, Richard V.; Chipera, Steve; Rampe, Elizabeth B.; Farmer, Jack, D.; Treiman, Allan H; hide

    2013-01-01

    The Mars Science Laboratory (MSL) Rover, Curiosity spent approx 150 sols at Yellowknife Bay (YKB) studying a section of fluvio-lacustrine sedimentary rocks (with potential indications of volcanic influence), informally known as the Yellowknife Bay formation. YKB lies in a distal region of the Peace Vallis alluvial fan, which extends from the northern rim of Gale Crater toward the dune field at the base of Mt Sharp. Sedimentological and stratigraphic observations are consistent with the Yellowknife Bay formation being part of a distal fan deposit, which could be as young as middle Hesperian to even early Amazonian in age (approx 3.5 to 2.5 Ga). The Yellowknife Bay formation hosts a unit of mudstone called the Sheepbed member. Curiosity obtained powdered rock samples from two drill holes in the Sheepbed Member, named John Klein and Cumberland, and delivered them to instruments in Curiosity. Data from CheMin, a combined X-ray diffraction (XRD)/X-ray fluorescence instrument (XRF), has allowed detailed mineralogical analysis of mudstone powders revealing a clay mineral component of approx 20 wt.% in each sample. The clay minerals are important indicators of paleoenvironmental conditions and sensitive recorders of post-depositional alteration processes. The XRD pattern of John Klein reveals a 021 band consistent with a trioctahedral phyllosilicate. A broad peak at approx 10A with a slight inflexion at approx 12A indicates the presence of 2:1 type clay minerals in the John Klein sample. The trioctahedral nature of the clay minerals, breadth of the basal reflection, and presence of a minor component with larger basal spacing suggests that John Klein contains a trioctahedral smectite (probably saponite), whose interlayer is largely collapsed because of the low-humidity conditions. The XRD patterns show no evidence of corrensite (mixed-layer chlorite/smectite) or chlorite, which are typical diagenetic products of trioctahedral smectites when subjected to burial and heating

  19. Four Types of Deposits From Wet Conditions on Early Mars

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Each of these four panels shows a close-up view of a different type of geological deposit formed with the involvement of water, based on observations by NASA's Mars Reconnaissance Orbiter. All four date from the earliest period of Martian history, called the Noachian Period.

    The upper-left panel shows carbonates overlying clays in the Nili Fossae region of Mars. The view combines color-coded information from infrared spectral observations by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) with an underlying black-and-white image from the High Resolution Imaging Science Experiment (HiRISE) camera. Beneath a rough-textured capping rock unit (purple) lie banded olivine-bearing layers (yellow), which in some places have been partially or wholly altered to carbonate (green).

    The upper-right panel shows phyllosilicates and chlorides in the Terra Sirenum region, observed by CRISM and HiRISE. Medium-toned, finely fractured rocks containing chloride salts either underlie higher-standing, light-toned phyllosilicates or fill in low spots between them. Both sit on dark, eroded volcanic material.

    The lower-left panel shows the upper portion of canyon wall in Coprates Chasma, observed by HiRISE and CRISM. The chasm rim cuts across the middle of the image. The wall slopes down to the top of the image and continues outside the region shown, exposing multiple phyllosilicate-bearing layers in a section of rock 7 kilometers (4 miles) thick. Two of the layers shown here are finely fractured aluminum clays that dominate the lower half of the image, underlain by thin beds of iron-magnesium clays at the top of the image. The dark material is a remnant of an overlying layer of basaltic sand that has been partly eroded away by the wind.

    The lower-right panel shows phyllosilicates with vertically layered compositions in Mawrth Vallis, observed by HiRISE (presented in enhanced color) and CRISM. The brown-colored knob in the middle of the scene is a

  20. The mechanism of montmorillonite catalysis in RNA synthesis

    NASA Astrophysics Data System (ADS)

    Joshi, Prakash

    montmorillonite as reaction occurs. The application of the Scherer equation to the X-ray diffraction data showed differences in domain size. Modeling of the size of the activated nucleotide monomers and the charge on the montmorillonite surface provided an interpretation of how these factors influence adsorption. This research provides a basis for further understanding of the physical processes in the mechanism of this catalysis in prebiotic reactions. This research was supported by NASA Astrobiology Institute Grant NNA09DA80A. References: Aldersley, M.F., Joshi, P.C., Price, J.D., Ferris, J.P. The role of montmorillonite in its catalysis of RNA synthesis. Appl. Clay Sci. 54,1-14, 2011. Bishop, J.L., Dobrea, E.J.N., Mckeown, N.K., Parenta, M. Phyllos- ilicate diversity and past aqueous activity revealed at Mawrth Vallis, Mars. Science 321, 830-833, 2008. Joshi, P.C., Aldersley, M.F., Delano, J.W., Ferris, J.P., Mechanism of montmorillonite catalysis in the formation of RNA oligomers, J. Am. Chem. Soc., 131, 13369-13374, 2009.

  1. Autonomous Science Analyses of Digital Images for Mars Sample Return and Beyond

    NASA Technical Reports Server (NTRS)

    Gulick, V. C.; Morris, R. L.; Ruzon, M.; Roush, T. L.

    1999-01-01

    program has been dubbed the "Grad Student on Mars Project". We envision, for example, an appropriately intelligent Athena-like rover at the Pathfinder landing site might be able to traverse over the ridge towards "Twin Peaks" to obtain better information on the stratigraphy of these "streamlined islands" or of the size, composition and morphology of boulders located on them. Along the traverse, the intelligent rover would collect and analyze images and obtain spectra of geologically interesting features or regions. The intelligent rover might also traverse further up Arcs Vallis, and find additional paleoflood stage indicators such as slackwater deposits. Recognizing additional regions where boulders are imbricated, noting changes in their size, distribution, morphology, composition and the associated changes in channel geometry would yield important information on the outflow channel's paleoflood history, Representative images and associated supporting data from these locations could be downlinked to Earth along with the data requested by scientists from the previous uplink opportunity. Our initial work has focused on recognizing geologically interesting portions of images. Here we summarize some of the algorithms to date.

  2. Stratigraphy of Aeolis Dorsa, Mars: Stratigraphic context of the great river deposits

    NASA Astrophysics Data System (ADS)

    Kite, Edwin S.; Howard, Alan D.; Lucas, Antoine S.; Armstrong, John C.; Aharonson, Oded; Lamb, Michael P.

    2015-06-01

    . The time gap between the end of river deposition and the onset of yardang-forming layered deposits is constrained to >1 × 108 yr by the high density of impact craters embedded at the unconformity. The time gap between the end of alluvial-fan deposition and the onset of yardang-forming layered deposits was at least long enough for wind-induced saltation abrasion to erode 20-30 m into the alluvial-fan deposits. We correlate the yardang-forming layered deposits to the upper layers of Gale crater's mound (Mt. Sharp/Aeolis Mons), and the fan-shaped deposits to Peace Vallis fan in Gale crater. Alternations between periods of low mean obliquity and periods of high mean obliquity may have modulated erosion-deposition cycling in Aeolis. This is consistent with the results from an ensemble of simulations of Solar System orbital evolution and the resulting history of the obliquity of Mars. 57 of our 61 simulations produce one or more intervals of continuously low mean Mars obliquity that are long enough to match our Aeolis Dorsa unconformity data.

  3. Proposed Mars Surveyor Landing Sites in Northern Meridiani Sinus, Southern Elysium Planitia, and Argyre Planitia

    NASA Technical Reports Server (NTRS)

    Parker, T. J.; Edgett, K. S.

    1998-01-01

    materials have been attributed to unusually low-viscosity flood lavas from fissures south of the Elysium volcanic rise, or to lacustrine materials associated with a large, Amazonian lake at the source of Marte Vallis. Parker and Schenk presented evidence in support of the latter interpretation, though they attributed the putative shore morphology to an embayment of a northern plains ocean into the southern Elysium region. Detailed examination of the margin of the deposit, showing erosion, not simply burial, of small crater rims and fluidized ejecta blankets, also points to lacustrine or marine sedimentation rather than volcanic plains burial. The plains surface exhibits a "crusty" appearance that many researchers have attributed to pressure ridges in lava flows. In a lacustrine context, they also resemble pressure ridges in desiccated evaporite deposits and salt-rimmed pools (now dry) similar in scale and morphology to spectacular, hundred meter-scale pool rims in alkaline Lake Natron, East African Rift. The eroded highland margin surface adjacent to these plains appears to be fairly smooth, even at 15 m/pixel. Isolated knob inliers are scattered from a few kilometers to several tens of "kilometers apart. Heights of the knobs have not been measured yet but, based on experience with similar features in the Pathfinder landing ellipse, are probably typically on the order of several tens of meters high and smaller, though some of the largest knobs in the region are probably up to a few hundred meters high. Two craters larger than a kilometer in diameter, with fluidized deposits, lie nearby the proposed landing site. Very high-resolution images from MOC should help to determine whether a landing site navigable by the Athena rover could be placed in this region. The space between knobs and craters is large enough to enable placement of a target landing ellipse between them but still provide access to one or more of them and to the margin of the Elysium plains material. Post -2001

  4. Aram Chaos: a Long Lived Subsurface Aqueous Environment with Strong Water Resources Potential for Human Missions on Mars

    NASA Technical Reports Server (NTRS)

    Sibille, L.; Mueller, R.; Niles, P. B.; Glotch, T.; Archer, P. D.; Bell, M. S.

    2015-01-01

    Aram Chaos, Mars is a crater 280 kilometers in diameter with elevations circa. minus 2 to minus 3 kilometers below datum that provides a compelling landing site for future human explorers as it features multiple scientific regions of interest (ROI) paired with a rich extensible Resource ROI that features poly-hydrated sulfates [1]. The geologic history of Aram Chaos suggests several past episodes of groundwater recharge and infilling by liquid water, ice, and other materials [1-3]. The creation of the fractured region with no known terrestrial equivalent may have been caused by melting of deep ice reservoirs that triggered the collapse of terrain followed by catastrophic water outflows over the region. Aram Chaos is of particular scientific interest because it is hypothesized that the chaotic terrain may be the source of water that contributed to the creation of nearby valleys such as Ares Vallis flowing toward Chryse Planitia. The liquid water was likely sourced as groundwater and therefore represents water derived from a protected subsurface environment making it a compelling astrobiological site [2]. The past history of water is also represented by high concentrations of hematite, Fe-oxyhydroxides, mono-hydrated and poly-hydrated sulfates [1, 2]. Poly-hydrated sulfates are likely to contain abundant water that evolves at temperatures below 500 degrees Centigrade thus conferring Aram Chaos a potentially high value for early in-situ resource utilization (ISRU) [4]. The geologic history also calls for future prospecting of deep ice deposits and possibly liquid water via deep drilling. The most recent stratigraphic units in the central part of Aram Chaos are not fractured, and are part of a dome-shaped formation that features bright, poorly-consolidated material that contains both hydrated sulfates and ferric oxides according to OMEGA (Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité) data [5]. These surface material characteristics are

  5. Surface-based 3D measurements of small aeolian bedforms on Mars and implications for estimating ExoMars rover traversability hazards

    NASA Astrophysics Data System (ADS)

    Balme, Matt; Robson, Ellen; Barnes, Rob; Butcher, Frances; Fawdon, Peter; Huber, Ben; Ortner, Thomas; Paar, Gerhard; Traxler, Christoph; Bridges, John; Gupta, Sanjeev; Vago, Jorge L.

    2018-04-01

    Recent aeolian bedforms comprising loose sand are common on the martian surface and provide a mobility hazard to Mars rovers. The ExoMars rover will launch in 2020 to one of two candidate sites: Mawrth Vallis or Oxia Planum. Both sites contain numerous aeolian bedforms with simple ripple-like morphologies. The larger examples are 'Transverse Aeolian Ridges' (TARs), which stereo imaging analyses have shown to be a few metres high and up to a few tens of metres across. Where they occur, TARs therefore present a serious, but recognized and avoidable, rover mobility hazard. There also exists a population of smaller bedforms of similar morphology, but it is unknown whether these bedforms will be traversable by the ExoMars rover. We informally refer to these bedforms as "mini-TARs", as they are about an order of magnitude smaller than most TARs observed to date. They are more abundant than TARs in the Oxia Planum site, and can be pervasive in areas. The aim of this paper is to estimate the heights of these features, which are too small to measured using High Resolution Imaging Science Experiment (HiRISE) Digital Elevation Models (DEMs), from orbital data alone. Thereby, we aim to increase our knowledge of the hazards in the proposed ExoMars landing sites. We propose a methodology to infer the height of these mini-TARs based on comparisons with similar features observed by previous Mars rovers. We use rover-based stereo imaging from the NASA Mars Exploration Rover (MER) Opportunity and PRo3D software, a 3D visualisation and analysis tool, to measure the size and height of mini-TARs in the Meridiani Planum region of Mars. These are good analogues for the smaller bedforms at the ExoMars rover candidate landing sites. We show that bedform height scales linearly with length (as measured across the bedform, perpendicular to the crest ridge) with a ratio of about 1:15. We also measured the lengths of many of the smaller aeolian bedforms in the ExoMars rover Oxia Planum

  6. Layered Outcrops of Far West Candor Chasma

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site]

    Images from Mariner 9 in 1972 revealed that some of the mesas and mounds found within the chasms of the martian 'Grand Canyon'--the Valles Marineris--have layers in them. Speculations as to the origin of these interior layered materials ranged from volcanic ash deposits to sediments laid down in lakes that could have partially filled the Vallis Marineris troughs, much as lakes now occupy portions of the rift valleys of eastern Africa. The proposal that the Valles Marineris once hosted deep martian lakes led to additional speculation as to the prospects for finding fossil evidence of martian life.

    Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) images have ten or more times better resolution than the Mariner 9 and Viking orbiter images taken in the 1970s. MOC images have indeed confirmed the presence of layered outcrops within the Valles Marineris. They have also shown places previously not suspected to have layered rock, and they have shown that these materials might not have formed in the Valles Marineris, but were instead deposited in craters that were subsequently buried long before the chasms opened up (see discussion below). The layered rock is now visible because of faulting and erosion.

    The high resolution picture shown here (B, above right) was the first image received by MOC scientists that began to hint at a larger story of layered sedimentary rock on Mars. The picture shows a 1.5 km by 2.9 km (0.9 mi by 1.8 mi) area in far southwestern Candor Chasma (A, above left) that was--based on Mariner 9 and Viking orbiter images--not previously expected to exhibit layers. The MOC image reveals that the floor of western Candor Chasma at this location is indeed layered. What is most striking about the picture is the large number and uniformity of the layers, or beds. There are over 100 beds in this area, and each has about the same thickness (estimated to be about 10 meters (11 yards) thick). Each layer

  7. Proposed Mars Surveyor landing sites in northern Meridiani Sinus, southern Elysium Planitia, and Argyre Planitia

    NASA Astrophysics Data System (ADS)

    Parker, T. J.; Edgett, K. S.

    1998-01-01

    at a sharp contact by an extensive plains unit in southern Elysium Planitia that is Amazonian in age. The plains materials have been attributed to unusually low-viscosity flood lavas [6] from fissures south of the Elysium volcanic rise, or to lacustrine material associated with a large, Amazonian lake at the source of Marte Vallis [7]. Parker and Schenk [8] presented evidence in support of the latter interpretation, though they attributed the putative shore morphology to an embayment of a northern plains ocean into the southern Elysium region. Detailed examination of the margin of the deposit, showing erosion, not simply burial, of small crater rims and fluidized ejecta blankets, also points to lacustrine or marine sedimentation rather than volcanic plains burial. The plains surface exhibits a "crusty" appearance that many researchers have attributed to pressure ridges in lava flows. In a lacustrine context, they also resemble pressure ridges in desiccated evaporite deposits and salt-rimmed pools (now dry) similar in scale and morphology to spectacular, hundred meter-scale pool rims in alkaline Lake Natron, East African Rift. The eroded highland margin surface adjacent to these plains appears to be fairly smooth, even at 15 m/pixel. Isolated knob inliers are scattered from a few kilometers to several tens of kilometers apart. Heights of the knobs have not been measured yet but, based on experience with similar features in the Pathfinder landing ellipse, are probably typically on the order of several tens of meters high and smaller, though some of the largest knobs in the region are probably up to a few hundred meters high. Two craters larger than a kilometer in diameter, with fluidized ejecta deposits, lie nearby the proposed landing site. Very high-resolution images from MOC should help to determine whether a landing site navigable by the Athena rover could be placed in this region. The space between knobs and craters is large enough to enable placement of a target

  8. Novel 3D imaging techniques for improved understanding of planetary surface geomorphology.

    NASA Astrophysics Data System (ADS)

    Muller, Jan-Peter

    2015-04-01

    Understanding the role of different planetary surface formation processes within our Solar System is one of the fundamental goals of planetary science research. There has been a revolution in planetary surface observations over the past decade for Mars and the Moon, especially in 3D imaging of surface shape (down to resolutions of 75cm) and subsequent correction for terrain relief of imagery from orbiting and co-registration of lander and rover robotic images. We present some of the recent highlights including 3D modelling of surface shape from the ESA Mars Express HRSC (High Resolution Stereo Camera), see [1], [2] at 30-100m grid-spacing; and then co-registered to HRSC using a resolution cascade of 20m DTMs from NASA MRO stereo-CTX and 0.75m DTMs from MRO stereo-HiRISE [3]. This has opened our eyes to the formation mechanisms of megaflooding events, such as the formation of Iani Vallis and the upstream blocky terrain, to crater lakes and receding valley cuts [4]. A comparable set of products is now available for the Moon from LROC-WA at 100m [5] and LROC-NA at 1m [6]. Recently, a very novel technique for the super-resolution restoration (SRR) of stacks of images has been developed at UCL [7]. First examples shown will be of the entire MER-A Spirit rover traverse taking a stack of 25cm HiRISE to generate a corridor of SRR images along the rover traverse of 5cm imagery of unresolved features such as rocks, created as a consequence of meteoritic bombardment, ridge and valley features. This SRR technique will allow us for ˜400 areas on Mars (where 5 or more HiRISE images have been captured) and similar numbers on the Moon to resolve sub-pixel features. Examples will be shown of how these SRR images can be employed to assist with the better understanding of surface geomorphology. Acknowledgements: The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under PRoViDE grant agreement n° 312377

  9. Physical sense of massive development of low density minerals on the highly standing southern hemisphere of Mars

    NASA Astrophysics Data System (ADS)

    Kochemasov, Gennady G.

    2010-05-01

    of chlorides - they can indicate at widespread NaCl depositions (Mars Odyssey orbiter, M. Osterloo team of the Univ. of Hawaii, 2008). Zeolites replacing feldspathoids were predicted [4] and were reported among other not dense hydrated minerals [5] So, massive development of low density materials on the highlands serves as an effective tool for diminishing the angular momentum of the highly standing continental segment. References: [1] Kochemasov G. G. (2004) Mars and Earth: two dichotomies - one cause // In Workshop on "Hemispheres apart: the origin and modification of the martian crustal dichotomy", LPI Contribution # 1203, Lunar and Planetary Institute, Houston, p. 37. [2] Kochemasov G.G. (1995) Possibility of highly contrasting rock types at martian highland/lowland contact // Golombek M.P., Edgett K.S., Rice J.W.Jr. (eds) Mars Pathfinder Landing Site Workshop II: Characteristics of the Ares Vallis Region and Field Trips to the Channeled Scabland, Washington. LPI Tech. Rpt. 95-01. Pt. 1. Lunar and Planetary Inst., Houston, 1995. (63 p.), P. 18-19; [3] Kochemasov G.G. (2001) The composition of the martian highlands as a factor of their effective uplifting, destruction and production of voluminous debris // In: Field Trip and Workshop on the Martian Highlands and Mojave Desert Analogs, LPI contrib. #1101, Lunar & Planetary Inst., Houston, 35-36. [4] Kochemasov G.G.(2006)(abs.), posted Feb. 2006 in a Workshop on Martian Water: Surface and Subsurface, NASA Ames Research Center, Moffett Field, Calif., Febr. 23-24, 2006 at http://es.ucsc.edu/~fnimmo/website/mars2006.html. . [5] Ehlmann B.L., Mustard J.F., Murchie S.L. (2009) Extensive aqueous alternation of Mars' earliest crust: recent results from NASA's CRISM hyperspectral imager & implications for planetary habitability // Vernadsky-Brown Microsymposium 50, Mosow, Russia, Oct. 12-14, 2009, abstract m50_11.

  10. The Mars Pathfinder Mission and Science Results

    NASA Technical Reports Server (NTRS)

    Golombek, M. P.

    1999-01-01

    Mars Pathfinder, the first low-cost, quick Discovery class mission to be completed, successfully landed on the surface of Mars on July 4, 1997, deployed and navigated a small rover, and collected data from 3 science instruments and 10 technology experiments. The mission operated on Mars for 3 months and returned 2.3 Gbits of new data, including over 16,500 lander and 550 rover images, 16 chemical analyses of rocks and soil, and 8.5 million individual temperature, pressure and wind measurements. The rover traversed 100 m clockwise around the lander, exploring about 200 square meters of the surface. The mission captured the imagination of the public, and garnered front page headlines during the first week. A total of about 566 million internet "hits" were registered during the first month of the mission, with 47 million "hits" on July 8th alone, making the Pathfinder landing by far the largest internet event in history at the time. Pathfinder was the first mission to deploy a rover on Mars. It carried a chemical analysis instrument, to characterize the rocks and soils in a landing area over hundreds of square meters on Mars, which provided a calibration point or "ground truth" for orbital remote sensing observations. The combination of spectral imaging of the landing area by the lander camera, chemical analyses aboard the rover, and close-up imaging of colors, textures and fabrics with the rover cameras offered the potential of identifying rocks (petrology and mineralogy). With this payload, a landing site in Ares Vallis was selected because it appeared acceptably safe and offered the prospect of analyzing a variety of rock types expected to be deposited by catastrophic floods, which enabled addressing first-order scientific questions such as differentiation of the crust, the development of weathering products, and the nature of the early Martian environment and its subsequent evolution. The 3 instruments and rover allowed seven areas of scientific investigation: the

  11. Esker-based computation of glacial load and new insights into glacio-fluvial depositional settings in southern Argyre Planitia, Mars

    NASA Astrophysics Data System (ADS)

    Bernhardt, Hannes; Hiesinger, Harald; Reiss, Dennis; Ivanov, Mikhail; Erkeling, Gino

    2013-04-01

    1. Introduction The southern rim of the Argyre basin on Mars between -52°S/-59°S and 310°E/322°E shows several landforms of likely glacio-fluvial origin [e.g., 1,2,3,4,5]. We compiled a new a detailed geomorphologic map of the study area, whose southern half consists of the heterogeneous Charitum Montes highland terrain representing the southern rim of the Argyre basin. The northern half represents the southern basin floor consisting mostly of rough, layered terrain, slowly changing to intermediate and smooth terrain within a ~100 km wide zone circumferential to the Charitum Montes. Sinuous, layered and branching ridges, up to 300 km in length and 160 m in height can be seen on the basin floor with their apparent vertices being located close to the mouth of Surius Vallis. 2. Morphology and stratigraphy Absolute model ages based on crater counts on the basin floor suggest a formation of the esker-like ridges along with a suite of layered sediments ~3.7 - 3.5 Gyr ago. On the basis of the braided pattern and state of degradation of the sinuous ridges, we subdivided them into two populations (relatively pristine and braiding vs. degraded and solitary), which could in turn reflect changing conditions of glacial retreat: Based on the analysis of crest shapes of the more pristine ridges and their surrounding surface gradients, we used the transition method and the oblique path method [6,7] to compute four ice surface gradients of the glacier under which they might have formed. According to this reconstruction, the ice sheet reached a thickness of ~2 km if a conservative glacial terminus near the end of the easternmost ridge is applied. This would imply at least ~100,000-150,000 km³ of ice on the southern floor of the Argyre basin during the time the relatively pristine ridges were deposited. 3. Discussion In order to explain the transition of layers from the ridges into their surroundings, subglacial cavities in contact with subice channels have previously been

  12. Auqakuh Valles

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 7 June 2002) The Science This ancient sinuous river channel, located near 30o N, 299o W (61o E), was likely carved by water early in Mars history. Auqakuh Valles cuts through a remarkable series of rock layers that were deposited and then subsequently eroded. This change from conditions favoring deposition to those favoring erosion indicates that the environment of this region has changed significantly over time. In addition, the different rock layers seen in this image vary in hardness, with some being relatively soft and easily eroded, whereas others are harder and resistant. These differences imply that these layers vary in their composition, physical properties, and/or degree of cementation, and again suggest that major changes have occurred during the history of this region. Similar differences occur throughout the southwest U.S., where hard rock layers, such as the limestones and sandstones in the Grand Canyon, form resistant cliffs, whereas softer mudstones are easily eroded to form broad slopes. The Martian layers, such as the smooth, dark-toned mesas visible in numerous places to the right (east) of the channel, were once continuous across the region. As these layers have eroded, they have produced a wide array of textures, from smooth surfaces, to knobby terrains, to the unusual lobate patterns seen in the upper right of the image. The most recent activity in the region appears to be the formation of mega-ripples by the wind. These ripples, spaced approximately 75 m apart, form perpendicular to the wind direction, and can be seen following the pattern of the channel floor as it curves through this region. This pattern shows that even this relatively small channel, which varies in width from about 500 to 750 m throughout this image, acts to funnel the wind down the channel. The Story Auqakuh Vallis, an ancient river channel that winds its way down the center of this image, is the 'fossil' remains of an earlier, probably more watery time in

  13. Evidence for Recent Liquid Water on Mars: Clues Regarding the Relative Youth of Martian Gullies

    NASA Technical Reports Server (NTRS)

    2000-01-01

    How recent is 'recent'? The small martian gullies discovered in Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) pictures of certain craters, troughs, and valleys between latitudes 30o and 70o appear to be geologically young. This means that, on the scale of a planet that is 4.5billion years old, the gullies may be only a few million, or less, years old. The youth of these gullies relative to the history of Mars is indicated by the lack of impact craters--formed by meteors--on the alcoves, channels, or aprons of these features. However, other evidence suggests that the gullies may, in many cases, be much younger than a few million years--in fact, some might be actively seeping water in modern times.

    The first picture, 'Apron Covering Dunes,' shows a deep, prominent martian gully in a south-facing wall in Nirgal Vallis near 29.4oS, 39.1oW. Sunlight illuminates the scene from the upper left. At the bottom of the picture is a series of evenly-spaced, almost parallel ridges. These ridges are dunes created by windblown sand. The apron--the fanlike deposit at the lower end of the deep channel--at this location is seen covering some of the dunes. The sand dunes are thus older than the apron of debris that came from the channel. The dune field has no small meteor impact craters on it, so it, like the gully landforms, is geologically young--yet older than the apron. If the dunes are active in the modern environment--which is uncertain despite the apparent youth of the dunes--then the apron would have had to form within the past few centuries or less. This picture was taken in September 1999.

    The second picture, 'Apron on Polygons,' shows aprons deposited at the base of the south-facing slope in an impact crater at 54.8oS, 342.5oW, in Noachis Terra. The slope and plains surrounding the apron materials have a bumpy pattern of evenly-spaced polygons. Polygonal patterns like this are common in the middle and high latitude regions of Mars, and, like their

  14. Geologic map of the Ganiki Planitia quadrangle (V-14), Venus

    USGS Publications Warehouse

    Grosfils, Eric B.; Long, Sylvan M.; Venechuk, Elizabeth M.; Hurwitz, Debra M.; Richards, Joseph W.; Drury, Dorothy E.; Hardin, Johanna

    2011-01-01

    The Ganiki Planitia (V-14) quadrangle on Venus, which extends from 25° N. to 50° N. and from 180° E. to 210° E., derives its name from the extensive suite of plains that dominates the geology of the northern part of the region. With a surface area of nearly 6.5 x 106 km2 (roughly two-thirds that of the United States), the quadrangle is located northwest of the Beta-Atla-Themis volcanic zone and southeast of the Atalanta Planitia lowlands, areas proposed to be the result of large scale mantle upwelling and downwelling, respectively. The region immediately south of Ganiki Planitia is dominated by Atla Regio, a major volcanic rise beneath which localized upwelling appears to be ongoing, whereas the area just to the north is dominated by the orderly system of north-trending deformation belts that characterize Vinmara Planitia. The Ganiki Planitia quadrangle thus lies at the intersection between several physiographic regions where extensive mantle flow-induced tectonic and volcanic processes are thought to have occurred. The geology of the V-14 quadrangle is characterized by a complex array of volcanic, tectonic, and impact-derived features. There are eleven impact craters with diameters from 4 to 64 km, as well as four diffuse 'splotch' features interpreted to be the product of near-surface bolide explosions. Tectonic activity has produced heavily deformed tesserae, belts of complex deformation and rifts as well as a distributed system of fractures and wrinkle ridges. Volcanic activity has produced extensive regional plains deposits, and in the northwest corner of the quadrangle these plains host the initial (or terminal) 700 km of the Baltis Vallis canali, an enigmatic volcanic feature with a net length of ~7,000 km that is the longest channel on Venus. Major volcanic centers in V-14 include eight large volcanoes and eight coronae; all but one of these sixteen features was noted during a previous global survey. The V-14 quadrangle contains an abundance of minor

  15. From the North American Great Basin to the planet Mars: Taking Lacustrine Geomorphology into the 21st Century

    NASA Astrophysics Data System (ADS)

    Edgett, Kenneth S.; Parker, Timothy J.

    1997-09-01

    basis of study for the past two decades. In the mid-1980s some investigators began to speak of Mars as having a more "wet" history than was discussed earlier [3, 4]. Parker et al. [5-7] showed similarities between landforms along the margins of the great northern plains of Mars and landforms along the margins of Great Basin Lakes Bonneville and Lahontan; this work has stimulated much additional research [e.g., 8] and controversy [e.g., 9]. Others began to identify smaller basins that seem to contain sediments deposited by various channels. Among the earliest convincing arguments were presented by De Hon [10], who simply noted the occurrence of places where water had ponded along the course of some of the giant martian outflow channels. Evidence Mounts: The most commonly-cited place on Mars that may have been an ancient lake is within a 175 km-diameter crater, Gusev, located at 5°S, 184.5°W. A channel, Ma'adim Vallis, flowed into this crater; and an eroded, delta-like deposit is found at the site where the channel contacts the basin. This particular site has been repeatedly described in recent years as a place worthy of future Mars landers and sample returns, largely because it is one of the few possible lake features that most of the Mars science community can agree upon. Many more possible ancient lakebeds have been identified and summarized by Goldspiel and Squyres [11], Scott et al. [12], De Hon [13], Wharton et al. [14], and Parker and Currey [15]. Most of the proposed lakebeds are areas of low elevation where one or more channels appear to terminate at the location of a smooth, flat-lying deposit. In some cases, the smooth deposit has been eroded to form buttes and mesas. Other lake features are identified on the basis of thick, layered deposits [16]; or high-albedo deposits on crater floors, interpreted to be possible evaporates [17]. Parker [18, 19] has continued the approach of looking for Bonneville-like paleoshore features, but has moved from looking at the

  16. MOC's Highest Resolution View of Mars Pathfinder Landing Site

    NASA Technical Reports Server (NTRS)

    2000-01-01

    states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander; their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards (which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view.

    The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two