Ismenius Lacus quadrangle - Revision history

Suitupshowup: /* Upper Plains Unit */ added ref

2026-03-25T01:04:08Z

Upper Plains Unit: added ref

Suitupshowup: removed image

2026-03-10T23:06:07Z

removed image

Suitupshowup: added image

2026-03-10T23:04:48Z

added image

Suitupshowup: /* Other craters */

2026-03-10T16:59:35Z

Other craters

Suitupshowup: /* Dunes */

2026-02-26T23:40:35Z

Dunes

Suitupshowup: /* Glaciers */ added new info and ref

2025-09-01T21:55:13Z

Glaciers: added new info and ref

Suitupshowup: /* Glaciers */ added ref

2025-06-02T19:35:16Z

Glaciers: added ref

Suitupshowup at 16:04, 24 January 2025

2025-01-24T16:04:53Z

Suitupshowup: /* Other craters */ added more description

2025-01-22T16:09:45Z

Other craters: added more description

Suitupshowup: /* Other craters */ added more description

2025-01-22T16:02:52Z

Other craters: added more description

@@ Line 424: / Line 424: @@
 </gallery>
-This unit also degrades into "brain terrain."  Brain terrain is a region of maze-like ridges 3–5 meters high.  The closed cell brain terrain may still hold an ice core, so they may be sources of water for future colonists.
+This unit also degrades into "brain terrain." <ref> https://www.hou.usra.edu/meetings/lpsc2026/pdf/1626.pdf</ref>  <ref>Dundas, C., et al.  2026.  STRATIGRAPHIC OBSERVATIONS OF MARTIAN “BRAIN TERRAIN” AND IMPLICATIONS FOR
 <gallery class="center"  widths="380px" heights="360px">

← Older revision		Revision as of 23:06, 10 March 2026
Line 24:		Line 24:
	Typical features of Ismenius Lacus quadrangle		Typical features of Ismenius Lacus quadrangle

−
−	~~[[File:Collage ismenius lacus 02.jpg\|More ypical features of Ismenius Lacus quadrangle, as seen by HiRISE under under HiWish program\|600pxr\| More typical features of Ismenius Lacus quadrangle]]~~
−
−	~~More typical features of Ismenius Lacus quadrangle~~

	This quadrangle has some of the most mysterious-looking landscapes on the planet. It truly looks like another world here. Strong evidence of a past ocean on Mars exists in this region and is described below. The Ismenius Lacus quadrangle contains regions called Deuteronilus Mensae and Protonilus Mensae, two places that are of special interest to scientists. They contain abundant evidence of present and past glacial activity. They also have a landscape unique to Mars, called Fretted terrain. The largest crater in the area is Lyot Crater, which contains channels probably carved by liquid water.<ref>Carter \| first1 = J. \| last2 = Poulet \| first2 = F. \| last3 = Bibring \| first3 = J.-P. \| last4 = Murchie \| first4 = S. \| year = 2010 \| title = Detection of Hydrated Silicates in Crustal Outcrops in the Northern Plains of Mars \| url = \| journal = Science \| volume = 328 \| issue = 5986\| pages = 1682–1686 \| </ref>		This quadrangle has some of the most mysterious-looking landscapes on the planet. It truly looks like another world here. Strong evidence of a past ocean on Mars exists in this region and is described below. The Ismenius Lacus quadrangle contains regions called Deuteronilus Mensae and Protonilus Mensae, two places that are of special interest to scientists. They contain abundant evidence of present and past glacial activity. They also have a landscape unique to Mars, called Fretted terrain. The largest crater in the area is Lyot Crater, which contains channels probably carved by liquid water.<ref>Carter \| first1 = J. \| last2 = Poulet \| first2 = F. \| last3 = Bibring \| first3 = J.-P. \| last4 = Murchie \| first4 = S. \| year = 2010 \| title = Detection of Hydrated Silicates in Crustal Outcrops in the Northern Plains of Mars \| url = \| journal = Science \| volume = 328 \| issue = 5986\| pages = 1682–1686 \| </ref>

← Older revision		Revision as of 23:04, 10 March 2026
Line 17:		Line 17:

	[[File:Collage Ismenius Lacus quadrangle 03.jpg\|Typical features of Ismenius Lacus quadrangle, as seen by HiRISE under under HiWish program\|600pxr\| Typical features of Ismenius Lacus quadrangle]]		[[File:Collage Ismenius Lacus quadrangle 03.jpg\|Typical features of Ismenius Lacus quadrangle, as seen by HiRISE under under HiWish program\|600pxr\| Typical features of Ismenius Lacus quadrangle]]
		+
		+	Typical features of Ismenius Lacus quadrangle
		+
		+	[[File:Collage ismenius lacus 01.jpg\|Typical features of Ismenius Lacus quadrangle, as seen by HiRISE under under HiWish program\|600pxr\| Typical features of Ismenius Lacus quadrangle]]

	Typical features of Ismenius Lacus quadrangle		Typical features of Ismenius Lacus quadrangle

@@ Line 213: / Line 213: @@
 File:ESP 076130 2165craterdepositswide 01.jpg|Wide view of craters with strange deposits, as seen by HiRISE under HiWish program
 File:Close view of strange crater deposit 02.jpg|Close view of crater with strange, layered deposit, as seen by HiRISE
-File:Close view of strange crater deposit with layers 03.jpg|close view of crater with strange layered deposit
+File:Close view of strange crater deposit with layers 03.jpg|Close view of crater with strange layered deposit
 File:Crater with mesa ESP 074745 2105.jpg|Crater with mesa. First the crater was formed. Later material was deposited in the area. That material was eroded all over, except in this crater. This image was named HiRISE picture of the day for January 18, 2024.

@@ Line 614: / Line 614: @@
 <gallery class="center"  widths="380px" heights="360px">
 ESP 044861 2225dunes.jpg|Wide view of dunes in Moreux Crater
 </gallery>
 <gallery class="center"  widths="380px" heights="360px">
 File:55095 2170dunelinecolor.jpg|Close, color view of dunes, as seen by HiRISE under [[HiWish program]]
 File:55095 2170dunelinecolor2.jpg|Close, color view of dunes
 File:55095 2170dunelinecolor3.jpg|Close, color view of a dune
 </gallery>

@@ Line 259: / Line 259: @@
                    Glacier, as seen by HiRISE under HiWish program
-The Ismenius Lacus quadrangle might well be called the land of glaciers.  Glaciers formed much of the observable surface in large areas of Mars.  Much of the area in high latitudes, especially the Ismenius Lacus quadrangle, is believed to still contain enormous amounts of water ice.<ref>Hugh H. Kieffer (1992). Mars. University of Arizona Press. ISBN 978-0-8165-1257-7</ref> <ref> Plaut, J. et al. 2008. Radar Evidence for Ice in Lobate Debris Aprons in the Mid-Northern Latitudes of Mars. Lunar and Planetary Science XXXIX. 2290.pdf</ref> <ref>http://www.esa.int/SPECIALS/Mars_Express/SEMBS5V681F_0.html</ref>  In March 2010, scientists released the results of a radar study of an area called Deuteronilus Mensae that found widespread evidence of ice lying beneath a few meters of rock debris.<ref>http://news.discovery.com/space/mars-ice-sheet-climate.html</ref> The ice was probably deposited as snowfall during an earlier climate when the poles were tilted more.<ref>Madeleine, J. et al.  2007.  Exploring the northern mid-latitude glaciation with a general circulation model.  In:  Seventh International Conference on Mars.  Abstract 3096.</ref>  It would be difficult to take a hike on the fretted terrain where glaciers are common because the surface is folded, pitted, and often covered with linear striations.<ref>http://www.uahirise.org/ESP_018857_2225</ref>  The striations show the direction of movement.  Much of this rough texture is due to sublimation of buried ice.  The ice goes directly into a gas (this process is called sublimation) and leaves behind an empty space.  Overlying material then collapses into the void.<ref>http://hirise.lpl.arizona.edu/PSP_009719_2230</ref>  Glaciers are not pure ice; they contain dirt and rocks.  At times, they will dump their load of materials into ridges.  Such ridges are called moraines.
+The Ismenius Lacus quadrangle might well be called the land of glaciers.  Glaciers formed much of the observable surface in large areas of Mars.  Much of the area in high latitudes, especially the Ismenius Lacus quadrangle, is believed to still contain enormous amounts of water ice.<ref>Hugh H. Kieffer (1992). Mars. University of Arizona Press. ISBN 978-0-8165-1257-7</ref> <ref> Plaut, J. et al. 2008. Radar Evidence for Ice in Lobate Debris Aprons in the Mid-Northern Latitudes of Mars. Lunar and Planetary Science XXXIX. 2290.pdf</ref> <ref>http://www.esa.int/SPECIALS/Mars_Express/SEMBS5V681F_0.html</ref>  In March 2010, scientists released the results of a radar study of an area called Deuteronilus Mensae that found widespread evidence of ice lying beneath a few meters of rock debris.<ref>http://news.discovery.com/space/mars-ice-sheet-climate.html</ref> The ice was probably deposited as snowfall during an earlier climate when the poles were tilted more.<ref>Madeleine, J. et al.  2007.  Exploring the northern mid-latitude glaciation with a general circulation model.  In:  Seventh International Conference on Mars.  Abstract 3096.</ref>
 <gallery class="center"  widths="380px" heights="360px">

@@ Line 303: / Line 303: @@
 Image:Glacier as seen by ctx.JPG|Mesa in Ismenius Lacus quadrangle, as seen by CTX.  Mesa has several glaciers eroding it.  One of the glaciers is seen in greater detail in the next two images from HiRISE.
-Image:Wide view of glacier showing image field.JPG|Glacier as seen by HiRISE under the HiWish program.  Area in rectangle is enlarged in the next photo.  Zone of accumulation of snow at the top.  Glacier is moving down valley, then spreading out on plain.  Evidence for flow comes from the many lines on surface.  Location is in Protonilus Mensae.
+Image:Wide view of glacier showing image field.JPG|Glacier as seen by HiRISE under the HiWish program.  Area in rectangle is enlarged in the next photo.  Zone of accumulation of snow at the top.  Glacier is moving down valley, then spreading out on plain.  Evidence for flow comes from the many lines on surface.  Location is in Protonilus Mensae.<ref> https://www.uahirise.org/hipod/PSP_008809_2215</ref>
 Image:Glacier close up with hirise.JPG|Enlargement of area in rectangle of the previous image.  On Earth the ridge would be called the terminal moraine of an alpine glacier.

← Older revision		Revision as of 16:04, 24 January 2025
Line 16:		Line 16:


−	[[File:Collage ~~ismenius lacus 01~~.jpg\|Typical features of Ismenius Lacus quadrangle, as seen by HiRISE under under HiWish program\|600pxr\| Typical features of Ismenius Lacus quadrangle]]	+	[[File:Collage Ismenius Lacus quadrangle 03.jpg\|Typical features of Ismenius Lacus quadrangle, as seen by HiRISE under under HiWish program\|600pxr\| Typical features of Ismenius Lacus quadrangle]]

	Typical features of Ismenius Lacus quadrangle		Typical features of Ismenius Lacus quadrangle

@@ Line 176: / Line 176: @@
 Impact craters generally have a rim with ejecta around them; in contrast volcanic craters usually do not have a rim or ejecta deposits.  As craters get larger (greater than 10 km in diameter), they usually have a central peak.<ref>http://www.lpi.usra.edu/publications/slidesets/stones/</ref> The peak is caused by a rebound of the crater floor following the impact.<ref>Hugh H. Kieffer|title=Mars|url=https://books.google.com/books?id=NoDvAAAAMAAJ|accessdate=7 March 2011|date=1992|publisher=University of Arizona Press|isbn=978-0-8165-1257-7}}</ref>  Sometimes craters will display layers in their walls.  Since the collision that produces a crater is like a powerful explosion, rocks from deep underground are tossed unto the surface.  Hence, craters are useful for showing us what lies deep under the surface.  We can examine the ejecta to tell us about the nature of the rocks under the surface.
-Some ejecta is lower than the surrounding ground, this may be due to the hot ejecta melting ground ice.  On the other hand some craters and their ejecta sit on raised platforms or pedestals.  We call them pedestal craters.  The ejecta in these cases  proteced the underlying ground  from erosion. Ater a time, the crater ended up sitting higher.
 <gallery class="center"  widths="380px" heights="360px">

@@ Line 175: / Line 175: @@
 ==Other craters==
-Impact craters generally have a rim with ejecta around them; in contrast volcanic craters usually do not have a rim or ejecta deposits.  As craters get larger (greater than 10 km in diameter), they usually have a central peak.<ref>http://www.lpi.usra.edu/publications/slidesets/stones/</ref> The peak is caused by a rebound of the crater floor following the impact.<ref>Hugh H. Kieffer|title=Mars|url=https://books.google.com/books?id=NoDvAAAAMAAJ|accessdate=7 March 2011|date=1992|publisher=University of Arizona Press|isbn=978-0-8165-1257-7}}</ref>  Sometimes craters will display layers in their walls.  Since the collision that produces a crater is like a powerful explosion, rocks from deep underground are tossed unto the surface.  Hence, craters are useful for showing us what lies deep under the surface.
+Impact craters generally have a rim with ejecta around them; in contrast volcanic craters usually do not have a rim or ejecta deposits.  As craters get larger (greater than 10 km in diameter), they usually have a central peak.<ref>http://www.lpi.usra.edu/publications/slidesets/stones/</ref> The peak is caused by a rebound of the crater floor following the impact.<ref>Hugh H. Kieffer|title=Mars|url=https://books.google.com/books?id=NoDvAAAAMAAJ|accessdate=7 March 2011|date=1992|publisher=University of Arizona Press|isbn=978-0-8165-1257-7}}</ref>  Sometimes craters will display layers in their walls.  Since the collision that produces a crater is like a powerful explosion, rocks from deep underground are tossed unto the surface.  Hence, craters are useful for showing us what lies deep under the surface.  We can examine the ejecta to tell us about the nature of the rocks under the surface.
 <gallery class="center"  widths="380px" heights="360px">
@@ Line 185: / Line 186: @@
 File:ESP 054963 1950craterbench.jpg|Crater with a bench  A crater with a bench may be formed from settling of the crater wall or it may be due to impact into something with vastly different types of layers.
-File:ESP 066174 2110doublecrater.jpg|Double crater.  Box indicates the size of a football field in this scene.  This image was named HiRISE picture of the day.
+File:ESP 066174 2110doublecrater.jpg|Double crater.  Box indicates the size of a football field in this scene.  This image was named HiRISE picture of the day.  This was made when the impacting body broke into two right before it hit the ground.
 File:ESP 056953 2160expandedcraters.jpg|Possible expanded secondary craters, as seen by HiRISE under [[HiWish program]]  These craters may have become much wider, as ice left the ground around the rims.<ref>http://www.uahirise.org/epo/nuggets/expanded-secondary.pdf</ref> <ref>Viola, D., et al.  2014.  EXPANDED CRATERS IN ARCADIA PLANITIA: EVIDENCE FOR >20 MYR OLD SUBSURFACE ICE. Eighth International Conference on Mars (2014).  1022pdf.</ref>