Academia.eduAcademia.edu

Figure 2 – uploaded by David Pieri

See full PDFdownloadDownload figure
Fig. 15. Regional mosaic of the eastern Acidalia Planitia- Cydonia Mensae region of Mars. Gradational boundary indicated by black line; Interior plains boundary by white line. Gaps in these lines indicate regions where continuity is equivocal, either due to gaps in the available high resolution images or to subsequent modification of the boundaries. Subsequent figure locations are indicated.

Figure 15 Regional mosaic of the eastern Acidalia Planitia- Cydonia Mensae region of Mars. Gradational boundary indicated by black line; Interior plains boundary by white line. Gaps in these lines indicate regions where continuity is equivocal, either due to gaps in the available high resolution images or to subsequent modification of the boundaries. Subsequent figure locations are indicated.

Related Figures (22)

‘ig. la. Global sinusoidal projections of Mars showing distribution of plains boundaries vithin the northern lowlands (adapted from U.S. Geological Survey/NASA, [1991]). Shaded reas represent approximate extent of flooded portions of northern plains. Thick lines indicate ontacts that are well-expressed in medium to high resolution Viking Orbiter images and appear easonably well-preserved. Thin lines indicate contacts covered by lower resolution images nd/or less well-preserved. In areas such as Tharsis and Elysium, where the boundaries may ave been obscured by later volcanism, boundary location is approximated by thin lines (to nable closure). (Upper map) Youngest plains surface (boundary equivalent to contact 2 Parker et al., 1989}). Total area is approximately 27 x 106 km*. (Lower map) Earlier northern lains surface (boundary equivalent to contact 1 [Parker et al., 1989]). Total area is pproximately 46 x 10° km?. These data will then be used to describe an emerging lacustrine or marine model of the evolution of the northern plains. Preliminary comparisons between the volume of the basin and proposed source channels will be made to determine whether discrete channeling events are sufficient to fill a dry basin. Source volumes that are too small to do so may indicate A suite of features along and within the lowland/upland boundary have been interpreted as wave-generated shorelines of an ephemeral sea or ocean that formed as a consequence of
‘ig. la. Global sinusoidal projections of Mars showing distribution of plains boundaries vithin the northern lowlands (adapted from U.S. Geological Survey/NASA, [1991]). Shaded reas represent approximate extent of flooded portions of northern plains. Thick lines indicate ontacts that are well-expressed in medium to high resolution Viking Orbiter images and appear easonably well-preserved. Thin lines indicate contacts covered by lower resolution images nd/or less well-preserved. In areas such as Tharsis and Elysium, where the boundaries may ave been obscured by later volcanism, boundary location is approximated by thin lines (to nable closure). (Upper map) Youngest plains surface (boundary equivalent to contact 2 Parker et al., 1989}). Total area is approximately 27 x 106 km*. (Lower map) Earlier northern lains surface (boundary equivalent to contact 1 [Parker et al., 1989]). Total area is pproximately 46 x 10° km?. These data will then be used to describe an emerging lacustrine or marine model of the evolution of the northern plains. Preliminary comparisons between the volume of the basin and proposed source channels will be made to determine whether discrete channeling events are sufficient to fill a dry basin. Source volumes that are too small to do so may indicate A suite of features along and within the lowland/upland boundary have been interpreted as wave-generated shorelines of an ephemeral sea or ocean that formed as a consequence of
Fig. 1c. Regional mosaic of the western Isidis Planitia region of Mars. Interior plains boundary indicated by white line (gradational boundary obscured by younger Syrtis Major Volcanic plains). Gaps in this line indicates regions where continuity is equivocal, as in figure 1b. Subsequent figure locations are indicated.
Fig. 1c. Regional mosaic of the western Isidis Planitia region of Mars. Interior plains boundary indicated by white line (gradational boundary obscured by younger Syrtis Major Volcanic plains). Gaps in this line indicates regions where continuity is equivocal, as in figure 1b. Subsequent figure locations are indicated.
Fig. 2. Detailed views of sloped surfaces at the “gradational" boundary, with terrestrial analogs from Pleistocene Lake Bonneville. (a) Portion of high resolution Viking Orbiter image of "gradational" boundary on northward sloping margin of upland terrain in the northern Acheron Fossae region (39° latitude, 141° longitude). Contact runs from lower left to upper right corners of scene (base of slope to north). Inset image has been stretched to enhance subtle striations on slope parallel to the gradational boundary and lying between it and the lowland plains surface. Viking Orbiter image 129a32.
Fig. 2. Detailed views of sloped surfaces at the “gradational" boundary, with terrestrial analogs from Pleistocene Lake Bonneville. (a) Portion of high resolution Viking Orbiter image of "gradational" boundary on northward sloping margin of upland terrain in the northern Acheron Fossae region (39° latitude, 141° longitude). Contact runs from lower left to upper right corners of scene (base of slope to north). Inset image has been stretched to enhance subtle striations on slope parallel to the gradational boundary and lying between it and the lowland plains surface. Viking Orbiter image 129a32.
Fig. 2b. Concentric striae surrounding massifs in the northern plains. (Upper image) Group of massifs in upper image lie in Arcadia Planitia, east of Phlegra Montes (45° latitude, 186° longitude). Each massif has been stretched in boxes at right to enhance apron detail. Viking Orbiter image 076b84. (Lower image) Very high resolution (9.5 m/pixel) Viking Orbiter image mosaic of massif outlier in the Protonilus Mensae region (at 45° latitude, 317.5° longitude). Debris apron on northeast side (upper right) exhibits concentric striae on its surface that resolve into a system of gentle ridges and swales, or steps, on the sloped apron surface. Viking Orbiter images 461b08,09. Fig 2c. Stereo aerial photo triplet of strandlines cut into bajada surface in the northwest Lake Bonneville region of Utah. Mountain front is at bottom of scene. Bajada surface runs from center left to lower right. West edge (bottom of frame) of reworked bajada surface is Bonneville shoreline. Numerous striae parallel to shoreline are strandlines associated with receding lake levels (darkest is the Provo level). Compare this surface with Figure 2a. Dark feature at upper left is an island massif linked to the bajada by a tombolo. Varied albedo surface from top left to right center is modern active playa. Aerial photos courtesy Eros Data Center.
Fig. 2b. Concentric striae surrounding massifs in the northern plains. (Upper image) Group of massifs in upper image lie in Arcadia Planitia, east of Phlegra Montes (45° latitude, 186° longitude). Each massif has been stretched in boxes at right to enhance apron detail. Viking Orbiter image 076b84. (Lower image) Very high resolution (9.5 m/pixel) Viking Orbiter image mosaic of massif outlier in the Protonilus Mensae region (at 45° latitude, 317.5° longitude). Debris apron on northeast side (upper right) exhibits concentric striae on its surface that resolve into a system of gentle ridges and swales, or steps, on the sloped apron surface. Viking Orbiter images 461b08,09. Fig 2c. Stereo aerial photo triplet of strandlines cut into bajada surface in the northwest Lake Bonneville region of Utah. Mountain front is at bottom of scene. Bajada surface runs from center left to lower right. West edge (bottom of frame) of reworked bajada surface is Bonneville shoreline. Numerous striae parallel to shoreline are strandlines associated with receding lake levels (darkest is the Provo level). Compare this surface with Figure 2a. Dark feature at upper left is an island massif linked to the bajada by a tombolo. Varied albedo surface from top left to right center is modern active playa. Aerial photos courtesy Eros Data Center.
Fig. 3a. High resolution Viking Orbiter image mosaic and map of southwest Cydonia Mensae region (centered at 32° latitude, 17° longitude). Cratered upland surfaces and large, fresh impact craters are coded with light tone; gradational boundary and arcuate plains boundaries (both albedo boundaries and sharp breaks in slope) are delineated with solid black lines; curvilinear ridges are dark gray. Viking Orbiter images 227s04-15.
Fig. 3a. High resolution Viking Orbiter image mosaic and map of southwest Cydonia Mensae region (centered at 32° latitude, 17° longitude). Cratered upland surfaces and large, fresh impact craters are coded with light tone; gradational boundary and arcuate plains boundaries (both albedo boundaries and sharp breaks in slope) are delineated with solid black lines; curvilinear ridges are dark gray. Viking Orbiter images 227s04-15.
Fig. 2d. Stereo aerial photo pair of southwest Lake Bonneville, Utah. Horizontal steps are strandlines associated with recession of the lake from the Bonneville level. These strandlines are most easily visible in aerial photos when they lie on relatively gentle slopes that face the main body of the lake. Several prominent strandlines are seen to curve around from the right side of a promontory (at upper left) and fade out on its left side. The slope on the left side of the promontory is steeper than on the right, and the right side faces the main body of the lake. Wave energy was greater on the right side than on the left. Perhaps in similar fashion, the Protonilus massif in Figure 2c has concentric striae on its northeast side, which locally faces the open northern plains, away from the lowland/upland boundary escarpment. Aerial photos courtesy the Earth Technology Corporation.
Fig. 2d. Stereo aerial photo pair of southwest Lake Bonneville, Utah. Horizontal steps are strandlines associated with recession of the lake from the Bonneville level. These strandlines are most easily visible in aerial photos when they lie on relatively gentle slopes that face the main body of the lake. Several prominent strandlines are seen to curve around from the right side of a promontory (at upper left) and fade out on its left side. The slope on the left side of the promontory is steeper than on the right, and the right side faces the main body of the lake. Wave energy was greater on the right side than on the left. Perhaps in similar fashion, the Protonilus massif in Figure 2c has concentric striae on its northeast side, which locally faces the open northern plains, away from the lowland/upland boundary escarpment. Aerial photos courtesy the Earth Technology Corporation.
Fig. 3b. Enlarged and contrast enhanced view of region near bottom left in Figure 3a. Interior plains boundary winds around cluster of low knobs in center of scene. This boundary exhibits both erosion and onlapping of the intermediate plains surface. Areas where erosion has occurred are indicated with black arrows, while those at which onlapping is evident are indicated with white arrows.
Fig. 3b. Enlarged and contrast enhanced view of region near bottom left in Figure 3a. Interior plains boundary winds around cluster of low knobs in center of scene. This boundary exhibits both erosion and onlapping of the intermediate plains surface. Areas where erosion has occurred are indicated with black arrows, while those at which onlapping is evident are indicated with white arrows.
Fig. 3c. Enlarged and contrast enhanced view of region at bottom center in Figure 3a. Interior plains surface directly contacts cratered upland outlier where an erosional cliff has been cut (labeled PC). Note partial crater in upland surface at this location. Contact continues around plateau outlier as a sharp break in slope in the plains surface (labeled AB), and grades into a curvilinear ridge linking three small knobs with the outlier. This and other ridges are labeled CR.
Fig. 3c. Enlarged and contrast enhanced view of region at bottom center in Figure 3a. Interior plains surface directly contacts cratered upland outlier where an erosional cliff has been cut (labeled PC). Note partial crater in upland surface at this location. Contact continues around plateau outlier as a sharp break in slope in the plains surface (labeled AB), and grades into a curvilinear ridge linking three small knobs with the outlier. This and other ridges are labeled CR.
Fig. 4. High resolution Viking Orbiter image mosaic (centered at 15° latitude, 282° longitude) of the west Isidis Planitia region. Plains and upland units and interior plains boundary (curvilinear ridges and arcuate plains boundaries) are indicated as in Figure 3, though locally the cratered uplands and gradational boundary have been obscured by the Syrtis Major volcanic plains. Viking Orbiter images 151s01-14; 152s04-10,12-24; 153s11-17,21-24.
Fig. 4. High resolution Viking Orbiter image mosaic (centered at 15° latitude, 282° longitude) of the west Isidis Planitia region. Plains and upland units and interior plains boundary (curvilinear ridges and arcuate plains boundaries) are indicated as in Figure 3, though locally the cratered uplands and gradational boundary have been obscured by the Syrtis Major volcanic plains. Viking Orbiter images 151s01-14; 152s04-10,12-24; 153s11-17,21-24.
Fig. 5. High resolution Viking Orbiter image mosaic (centered at 39° latitude, 7° longitude) of "gradational" and "interior" plains boundaries in the northeast Cydonia Mensae region. Major plains and upland surfaces are labeled in map inset. Note arcuate shape of interior plains boundary, with concave elements facing the interior plains. Viking Orbiter images 070a16,18,20; 072a13-18.
Fig. 5. High resolution Viking Orbiter image mosaic (centered at 39° latitude, 7° longitude) of "gradational" and "interior" plains boundaries in the northeast Cydonia Mensae region. Major plains and upland surfaces are labeled in map inset. Note arcuate shape of interior plains boundary, with concave elements facing the interior plains. Viking Orbiter images 070a16,18,20; 072a13-18.
Fig. 8. Stereo aerial photo pairs of lacustrine analogs from Lake Bonneville to the martian stepped massifs. (a) Pavant Butte, a 300 m high volcanic cone near Delta, Utah. Pavant Butte is a basaltic ash cone that erupted into Lake Bonneville within 500 years of the lake's spillover at Red Rock Pass [Oviatt and Nash, 1989]. The Bonneville shore platform (white arrows) is about 80 m high and as much as 0.5 km wide. The southwest side of the cone has been completely eroded by wave action. Black arrow indicates sea cliff at the Provo level, which has undercut the Bonneville platform on Pavant Butte's north side. Aerial photos courtesy of U.S. Department of Agriculture.
Fig. 8. Stereo aerial photo pairs of lacustrine analogs from Lake Bonneville to the martian stepped massifs. (a) Pavant Butte, a 300 m high volcanic cone near Delta, Utah. Pavant Butte is a basaltic ash cone that erupted into Lake Bonneville within 500 years of the lake's spillover at Red Rock Pass [Oviatt and Nash, 1989]. The Bonneville shore platform (white arrows) is about 80 m high and as much as 0.5 km wide. The southwest side of the cone has been completely eroded by wave action. Black arrow indicates sea cliff at the Provo level, which has undercut the Bonneville platform on Pavant Butte's north side. Aerial photos courtesy of U.S. Department of Agriculture.
Fig. 8b. Wave-eroded island in northern Lake Bonneville. Massif consists of fractured quartzite with carbonate cementing fractures. Prominent shore platform is cut at the Bonneville highstand. Bench on slope to east is the Provo level. Aerial photos courtesy Donald Currey, University of Utah.
Fig. 8b. Wave-eroded island in northern Lake Bonneville. Massif consists of fractured quartzite with carbonate cementing fractures. Prominent shore platform is cut at the Bonneville highstand. Bench on slope to east is the Provo level. Aerial photos courtesy Donald Currey, University of Utah.
Fig. 9. Sketch map of the Magdalen Islands, a series of small bedrock islands linked by long barrier beaches, or tombolos, in the Gulf of St. Lawrence, Quebec [adapted from Owens and McCann, 1980]. Dark gray indicates bedrock islands; wave pattern indicates Gulf of St. Lawrence and lagoons; medium gray indicates barrier beaches and spits; large arrows are dominant wind resultants; small arrows are longshore current directions. Compare this map with distribution of curvilinear ridges relative to massifs in Figure 3.
Fig. 9. Sketch map of the Magdalen Islands, a series of small bedrock islands linked by long barrier beaches, or tombolos, in the Gulf of St. Lawrence, Quebec [adapted from Owens and McCann, 1980]. Dark gray indicates bedrock islands; wave pattern indicates Gulf of St. Lawrence and lagoons; medium gray indicates barrier beaches and spits; large arrows are dominant wind resultants; small arrows are longshore current directions. Compare this map with distribution of curvilinear ridges relative to massifs in Figure 3.
Fig. 10a. High resolution Viking Orbiter image mosaic of part of lower Ares Vallis (25° latitude, 30° longitude). Inset illustrates principal morphologic elements: dark gray is the preflood plains surface; medium gray is the channel floor; light gray is the lobate, high albedo deposit. Lobate, high albedo deposit appears to have flowed southward, opposite the direction of channel flow. Numerous curvilinear ridges are confined to this unit. Viking Orbiter images 670a12-15.
Fig. 10a. High resolution Viking Orbiter image mosaic of part of lower Ares Vallis (25° latitude, 30° longitude). Inset illustrates principal morphologic elements: dark gray is the preflood plains surface; medium gray is the channel floor; light gray is the lobate, high albedo deposit. Lobate, high albedo deposit appears to have flowed southward, opposite the direction of channel flow. Numerous curvilinear ridges are confined to this unit. Viking Orbiter images 670a12-15.
Fig. 106. Enlargement of west bank of lower Ares Valles showing deflection of lobate, high albedo deposit (black arrows) around knobs at margin of channel floor (white arrows).
Fig. 106. Enlargement of west bank of lower Ares Valles showing deflection of lobate, high albedo deposit (black arrows) around knobs at margin of channel floor (white arrows).
Fig. 12. Medium resolution Viking Orbiter image mosaic of lobate, high albedo deposit in southwest Utopia Planitia (28° latitude, 270° longitude). Black arrows indicate inferred flow direction of bright material around knobs (white arrows). Open, topographically lower plains are toward right side of frame, lowland/upland boundary is toward left. Scene width, approximately 75 km. North is toward top of frame. Viking Orbiter images 572a26,28. Fig. 11. Medium resolution Viking Orbiter image mosaic of channel scour in vicinity of craters Kipini (top center) and Wahoo (bottom left). Lower Ares Vallis is at right, "coalesced" Chryse channels at left of center. Inset map highlights apparent flow of lobate, high albedo deposit up-channel from the plains. Area of Figure 10 is at upper right corner. Viking Orbiter images 827a21,22.
Fig. 12. Medium resolution Viking Orbiter image mosaic of lobate, high albedo deposit in southwest Utopia Planitia (28° latitude, 270° longitude). Black arrows indicate inferred flow direction of bright material around knobs (white arrows). Open, topographically lower plains are toward right side of frame, lowland/upland boundary is toward left. Scene width, approximately 75 km. North is toward top of frame. Viking Orbiter images 572a26,28. Fig. 11. Medium resolution Viking Orbiter image mosaic of channel scour in vicinity of craters Kipini (top center) and Wahoo (bottom left). Lower Ares Vallis is at right, "coalesced" Chryse channels at left of center. Inset map highlights apparent flow of lobate, high albedo deposit up-channel from the plains. Area of Figure 10 is at upper right corner. Viking Orbiter images 827a21,22.
Fig. 13. High resolution Viking Orbiter image mosaic of "channel fissures" in northern Chryse (28° latitude, 34° longitude). Channel flow direction was toward upper right. Inset map highlights longitudinally dominant rectilinear pattem of fissures. Viking Orbiter images 670a12-15.
Fig. 13. High resolution Viking Orbiter image mosaic of "channel fissures" in northern Chryse (28° latitude, 34° longitude). Channel flow direction was toward upper right. Inset map highlights longitudinally dominant rectilinear pattem of fissures. Viking Orbiter images 670a12-15.
Fig. 14. Stereo aerial photos of pingos and a pingo-like ice-cored hill on the Tuktoyaktuk Peninsula of the Canadian Arctic Coast (69° latitude, 133°W Longitude). (Upper pair) "Split Pingo" (upper) and "Ibyuk Pingo” (lower) and the drained thaw-lakes in which they formed (now inundated during high tides). (Lower pair) Pingo-like ice-cored hill in same general vicinity. Though exact origin is problematic, this structure exhibits a small spring at its summit on the northeast side, suggesting an active water lens under pressure beneath the hill.
Fig. 14. Stereo aerial photos of pingos and a pingo-like ice-cored hill on the Tuktoyaktuk Peninsula of the Canadian Arctic Coast (69° latitude, 133°W Longitude). (Upper pair) "Split Pingo" (upper) and "Ibyuk Pingo” (lower) and the drained thaw-lakes in which they formed (now inundated during high tides). (Lower pair) Pingo-like ice-cored hill in same general vicinity. Though exact origin is problematic, this structure exhibits a small spring at its summit on the northeast side, suggesting an active water lens under pressure beneath the hill.
Related topics:
image resolution
580 California St., Suite 400
San Francisco, CA, 94104
© 2025 Academia. All rights reserved