New Map Provides More Evidence Mars Once Like Earth (Forwarded)

Cynthia O'Carroll
Goddard Space Flight Center, Greenbelt, Md. October 12, 2005

New Map Provides More Evidence Mars Once Like Earth

NASA scientists have discovered additional evidence that Mars once
underwent plate tectonics, slow movement of the planet's crust, like the
present-day Earth. A new map of Mars' magnetic field made by the Mars
Global Surveyor spacecraft reveals a world whose history was shaped by
great crustal plates being pulled apart or smashed together.

Scientists first found evidence of plate tectonics on Mars in 1999.
Those initial observations, also done with the Mars Global Surveyor's
magnetometer, covered only one region in the Southern Hemisphere. The
data was taken while the spacecraft performed an aerobraking maneuver,
and so came from differing heights above the crust.

This high resolution magnetic field map, the first of its kind, covers
the entire surface of Mars. The new map is based on four years of data
taken in a constant orbit. Each region on the surface has been sampled
many times. "The more measurements we obtain, the more accuracy, and
spatial resolution, we achieve," said Dr. Jack Connerney,
co-investigator for the Mars Global Surveyor magnetic filed
investigation at NASA's Goddard Space Flight Center, Greenbelt, Md.

"This map lends support to and expands on the 1999 results," said Dr.
Norman Ness of the Bartol Research Institute at the University of
Delaware, Newark. "Where the earlier data showed a "striping" of the
magnetic field in one region, the new map finds striping elsewhere. More
importantly, the new map shows evidence of features, transform faults,
that are a "tell-tale" of plate tectonics on Earth." Each stripe
represents a magnetic field pointed in one direction* -- positive or
negative* -- and the alternating stripes indicate a "flipping" of the
direction of the magnetic field from one stripe to another.

Scientists see similar stripes in the crustal magnetic field on Earth.
Stripes form whenever two plates are being pushed apart by molten rock
coming up from the mantle, such as along the Mid-Atlantic Ridge. As the
plate spreads and cools, it becomes magnetized in the direction of the
Earth's strong global field. Since Earth's global field changes
direction a few times every million years, on average, a flow that cools
in one period will be magnetized in a different direction than a later
flow. As the new crust is pushed out and away from the ridge, stripes of
alternating magnetic fields aligned with the ridge axis develop.
Transform faults, identified by "shifts" in the magnetic pattern, occur
only in association with spreading centers.

To see this characteristic magnetic imprint on Mars indicates that it,
too, had regions where new crust came up from the mantle and spread out
across the surface. And when you have new crust coming up, you need old
crust plunging back down* -- the exact mechanism for plate tectonics.

Connerney points out that plate tectonics provides a unifying framework
to explain several Martian features. First, there is the magnetic
pattern itself. Second, the Tharsis volcanoes lie along a straight line.
These formations could have formed from the motion of a crustal plate
over a fixed "hotspot" in the mantle below, just as the Hawaiian islands
on Earth are thought to have formed. Third, the Valles Marineris, a
large canyon six times as long as the Grand Canyon and eight times as
deep, looks just like a rift formed on Earth by a plate being pulled
apart. Even more, it is oriented just as one would expect from plate
motions implied by the magnetic map.

"It's certainly not an exhaustive geologic analysis," said Dr. Mario
Acuña, principal investigator for the Mars Global Surveyor magnetic
filed investigation at Goddard Space Flight Center. "But plate tectonics
does give us a consistent explanation of some of the most prominent
features on Mars."

Results were published in the Oct. 10 edition of the Proceedings of the
National Academy of Science.

Other scientists working on the project included Dr. G. Kletetschka of
the Catholic University of America, Washington, DC, and Goddard Space
Flight Center; Dr. D.L. Mitchell and Dr. R.P. Lin of the University of
California at Berkeley; and Dr. H. Reme of the Centre d'Etude Spatiale
des Rayonnements in France. Dr. Acuña leads the international team that
built and operates the Mars Global Surveyor magnetometers. The Jet
Propulsion Laboratory, a division of the California Institute of
Technology in Pasadena, manages the mission for NASA's Science Mission
Directorate in Washington.

[NOTE: Images supporting this release are available at
http://www.nasa.gov/centers/goddard/...gs_plates.html ]

[NOTE: Images supporting this release are available at
http://www.nasa.gov/centers/goddard/...gs_plates.html ]

Andrew Yee wrote:

Transform faults, identified by "shifts" in the magnetic pattern, occur
only in association with spreading centers.

Active spreading centers are invariably accompanied by black smokers,
whose average ocean depth is 2.1 km.
http://www.ocean.udel.edu/kiosk/bsmoker.html
To achieve the same hydrostatic pressure, Mars' ocean had to be 6.3 km
deep. Another inference is that black smokers are invariably
accompanied by biota, which makes the search for fossils thinkable.
http://www.marinetech.org/nine_degrees/index.php
John Curtis

"John Curtis" wrote in message
ups.com...
[NOTE: Images supporting this release are available at
http://www.nasa.gov/centers/goddard/...gs_plates.html ]

Andrew Yee wrote:

Transform faults, identified by "shifts" in the magnetic pattern, occur
only in association with spreading centers.

Active spreading centers are invariably accompanied by black smokers,
whose average ocean depth is 2.1 km.
http://www.ocean.udel.edu/kiosk/bsmoker.html
To achieve the same hydrostatic pressure, Mars' ocean had to be 6.3 km
deep. Another inference is that black smokers are invariably
accompanied by biota, which makes the search for fossils thinkable.
http://www.marinetech.org/nine_degrees/index.php
John Curtis

Not all spreading center locations contain black smokers, though it is true
that black smokers are nearly always associated with spreading centers.
Having said that, there is no reason to assume that spreading centers on
Mars need to have had similarly associated black smokers. The black
smokers are where they are along Earth's spreading centers because there is
abundant water, high geothermal gradient at the spreading center location,
and abundant deep fissures in the rock. Remove any one of these, and you
won't get black smokers. These three elements are required in order to
initiate the kind of deep hydrothermal circulation pattern we see at black
smokers. To date, I know of no data collected from Mars orbiters or Rovers
that suggest the presence of black smokers in the areas where the asssumed
spreading centers are located. Ideed, we have only just scratched the
surface in studying the tectonics of Mars. I'd wait until more detailed
data comes in on these areas before making such premature conclusions.

George wrote:

Not all spreading center locations contain black smokers, though it is true
that black smokers are nearly always associated with spreading centers.
Having said that, there is no reason to assume that spreading centers on
Mars need to have had similarly associated black smokers. The black
smokers are where they are along Earth's spreading centers because there is
abundant water, high geothermal gradient at the spreading center location,
and abundant deep fissures in the rock.

and a deep ocean averaging 2.1km.
http://www.ocean.udel.edu/kiosk/bsmoker.html
Active ocean floor spreading, magnetic striping and black smokers are
manifestations of deep ocean vulcanism.
http://pubs.usgs.gov/publications/te...anchor10748934
John Curtis

Remove any one of these, and you
won't get black smokers. These three elements are required in order to
initiate the kind of deep hydrothermal circulation pattern we see at black
smokers. To date, I know of no data collected from Mars orbiters or Rovers
that suggest the presence of black smokers in the areas where the asssumed
spreading centers are located. Ideed, we have only just scratched the
surface in studying the tectonics of Mars. I'd wait until more detailed
data comes in on these areas before making such premature conclusions.

"John Curtis" wrote in message
oups.com...

George wrote:

Not all spreading center locations contain black smokers, though it is
true
that black smokers are nearly always associated with spreading centers.
Having said that, there is no reason to assume that spreading centers on
Mars need to have had similarly associated black smokers. The black
smokers are where they are along Earth's spreading centers because there
is
abundant water, high geothermal gradient at the spreading center
location,
and abundant deep fissures in the rock.

and a deep ocean averaging 2.1km.
http://www.ocean.udel.edu/kiosk/bsmoker.html
Active ocean floor spreading, magnetic striping and black smokers are
manifestations of deep ocean vulcanism.
http://pubs.usgs.gov/publications/te...anchor10748934
John Curtis

I think the phrase "abundant water" would qualitfy as "deep ocean". I
think you know what I mean. But there are other places on earth where
spreading occurs besides the deep ocean. Yes? Like the East African rift
valley. Although vulcanism is common there, I don't know of any black
smokers there. That was my point, as it relates to Mars. Mars could very
well have had this kind of rifting, so there isn't necessarily any need to
come to the conclusion that because there was rifting on Mars, that there
were black smokers, and hence, life.

Remove any one of these, and you
won't get black smokers. These three elements are required in order to
initiate the kind of deep hydrothermal circulation pattern we see at
black
smokers. To date, I know of no data collected from Mars orbiters or
Rovers
that suggest the presence of black smokers in the areas where the
asssumed
spreading centers are located. Ideed, we have only just scratched the
surface in studying the tectonics of Mars. I'd wait until more detailed
data comes in on these areas before making such premature conclusions.

See for example he

Plate Tectonics: The Mechanism.
http://www.ucmp.berkeley.edu/geology/tecmech.html

Bob Clark



Andrew Yee wrote:
Cynthia O'Carroll
Goddard Space Flight Center, Greenbelt, Md. October 12, 2005

New Map Provides More Evidence Mars Once Like Earth

NASA scientists have discovered additional evidence that Mars once
underwent plate tectonics, slow movement of the planet's crust, like the
present-day Earth. A new map of Mars' magnetic field made by the Mars
Global Surveyor spacecraft reveals a world whose history was shaped by
great crustal plates being pulled apart or smashed together.

Scientists first found evidence of plate tectonics on Mars in 1999.
Those initial observations, also done with the Mars Global Surveyor's
magnetometer, covered only one region in the Southern Hemisphere. The
data was taken while the spacecraft performed an aerobraking maneuver,
and so came from differing heights above the crust.

This high resolution magnetic field map, the first of its kind, covers
the entire surface of Mars. The new map is based on four years of data
taken in a constant orbit. Each region on the surface has been sampled
many times. "The more measurements we obtain, the more accuracy, and
spatial resolution, we achieve," said Dr. Jack Connerney,
co-investigator for the Mars Global Surveyor magnetic filed
investigation at NASA's Goddard Space Flight Center, Greenbelt, Md.

"This map lends support to and expands on the 1999 results," said Dr.
Norman Ness of the Bartol Research Institute at the University of
Delaware, Newark. "Where the earlier data showed a "striping" of the
magnetic field in one region, the new map finds striping elsewhere. More
importantly, the new map shows evidence of features, transform faults,
that are a "tell-tale" of plate tectonics on Earth." Each stripe
represents a magnetic field pointed in one direction* -- positive or
negative* -- and the alternating stripes indicate a "flipping" of the
direction of the magnetic field from one stripe to another.

Scientists see similar stripes in the crustal magnetic field on Earth.
Stripes form whenever two plates are being pushed apart by molten rock
coming up from the mantle, such as along the Mid-Atlantic Ridge. As the
plate spreads and cools, it becomes magnetized in the direction of the
Earth's strong global field. Since Earth's global field changes
direction a few times every million years, on average, a flow that cools
in one period will be magnetized in a different direction than a later
flow. As the new crust is pushed out and away from the ridge, stripes of
alternating magnetic fields aligned with the ridge axis develop.
Transform faults, identified by "shifts" in the magnetic pattern, occur
only in association with spreading centers.

To see this characteristic magnetic imprint on Mars indicates that it,
too, had regions where new crust came up from the mantle and spread out
across the surface. And when you have new crust coming up, you need old
crust plunging back down* -- the exact mechanism for plate tectonics.

Connerney points out that plate tectonics provides a unifying framework
to explain several Martian features. First, there is the magnetic
pattern itself. Second, the Tharsis volcanoes lie along a straight line.
These formations could have formed from the motion of a crustal plate
over a fixed "hotspot" in the mantle below, just as the Hawaiian islands
on Earth are thought to have formed. Third, the Valles Marineris, a
large canyon six times as long as the Grand Canyon and eight times as
deep, looks just like a rift formed on Earth by a plate being pulled
apart. Even more, it is oriented just as one would expect from plate
motions implied by the magnetic map.

"It's certainly not an exhaustive geologic analysis," said Dr. Mario
Acuña, principal investigator for the Mars Global Surveyor magnetic
filed investigation at Goddard Space Flight Center. "But plate tectonics
does give us a consistent explanation of some of the most prominent
features on Mars."

Results were published in the Oct. 10 edition of the Proceedings of the
National Academy of Science.

Other scientists working on the project included Dr. G. Kletetschka of
the Catholic University of America, Washington, DC, and Goddard Space
Flight Center; Dr. D.L. Mitchell and Dr. R.P. Lin of the University of
California at Berkeley; and Dr. H. Reme of the Centre d'Etude Spatiale
des Rayonnements in France. Dr. Acuña leads the international team that
built and operates the Mars Global Surveyor magnetometers. The Jet
Propulsion Laboratory, a division of the California Institute of
Technology in Pasadena, manages the mission for NASA's Science Mission
Directorate in Washington.

[NOTE: Images supporting this release are available at
http://www.nasa.gov/centers/goddard/...gs_plates.html ]

Robert Clark wrote:
See for example he

Plate Tectonics: The Mechanism.
http://www.ucmp.berkeley.edu/geology/tecmech.html



Has Stuart seen this? (Just wondering.)

Robert Clark wrote:
See for example he

Plate Tectonics: The Mechanism.
http://www.ucmp.berkeley.edu/geology/tecmech.html

Bob Clark


Where there is a fluid in motion,all celestial objects display both
differential rotation and an Equatorial bulge.

http://www.astronomynotes.com/starsun/sun-rotation.gif

As the rotations generates uni-directional rotation bands from
Equatorial to polar regions there is never any need to invoke
hemispherical Coriolis type explanations such asthe following one -

http://www.pa.msu.edu/~steinr/talks/mhd01/mdi.gif

As differential rotation bands implies seperate cells which straddle
the Equator rather than a hemispherical divisions which occur at the
Equator,there is no great difficulty in grafting in the mechanism for
the bulge with the component plates which make up that bulge.

Now,whatever you people imagine you are doing,it is obvious that you
don't take yourselves or geology seriously.As ignoring the largest
known geological feature -the shape of the planet, is no mean feat
whatever you choose to apply to crustal behavior is fine,the omission
of the largest geological feature from whatever mechnaism you choose
will always be a botched job.










Andrew Yee wrote:
Cynthia O'Carroll
Goddard Space Flight Center, Greenbelt, Md. October 12, 2005

New Map Provides More Evidence Mars Once Like Earth

NASA scientists have discovered additional evidence that Mars once
underwent plate tectonics, slow movement of the planet's crust, like the
present-day Earth. A new map of Mars' magnetic field made by the Mars
Global Surveyor spacecraft reveals a world whose history was shaped by
great crustal plates being pulled apart or smashed together.

Scientists first found evidence of plate tectonics on Mars in 1999.
Those initial observations, also done with the Mars Global Surveyor's
magnetometer, covered only one region in the Southern Hemisphere. The
data was taken while the spacecraft performed an aerobraking maneuver,
and so came from differing heights above the crust.

This high resolution magnetic field map, the first of its kind, covers
the entire surface of Mars. The new map is based on four years of data
taken in a constant orbit. Each region on the surface has been sampled
many times. "The more measurements we obtain, the more accuracy, and
spatial resolution, we achieve," said Dr. Jack Connerney,
co-investigator for the Mars Global Surveyor magnetic filed
investigation at NASA's Goddard Space Flight Center, Greenbelt, Md.

"This map lends support to and expands on the 1999 results," said Dr.
Norman Ness of the Bartol Research Institute at the University of
Delaware, Newark. "Where the earlier data showed a "striping" of the
magnetic field in one region, the new map finds striping elsewhere. More
importantly, the new map shows evidence of features, transform faults,
that are a "tell-tale" of plate tectonics on Earth." Each stripe
represents a magnetic field pointed in one direction* -- positive or
negative* -- and the alternating stripes indicate a "flipping" of the
direction of the magnetic field from one stripe to another.

Scientists see similar stripes in the crustal magnetic field on Earth.
Stripes form whenever two plates are being pushed apart by molten rock
coming up from the mantle, such as along the Mid-Atlantic Ridge. As the
plate spreads and cools, it becomes magnetized in the direction of the
Earth's strong global field. Since Earth's global field changes
direction a few times every million years, on average, a flow that cools
in one period will be magnetized in a different direction than a later
flow. As the new crust is pushed out and away from the ridge, stripes of
alternating magnetic fields aligned with the ridge axis develop.
Transform faults, identified by "shifts" in the magnetic pattern, occur
only in association with spreading centers.

To see this characteristic magnetic imprint on Mars indicates that it,
too, had regions where new crust came up from the mantle and spread out
across the surface. And when you have new crust coming up, you need old
crust plunging back down* -- the exact mechanism for plate tectonics.

Connerney points out that plate tectonics provides a unifying framework
to explain several Martian features. First, there is the magnetic
pattern itself. Second, the Tharsis volcanoes lie along a straight line.
These formations could have formed from the motion of a crustal plate
over a fixed "hotspot" in the mantle below, just as the Hawaiian islands
on Earth are thought to have formed. Third, the Valles Marineris, a
large canyon six times as long as the Grand Canyon and eight times as
deep, looks just like a rift formed on Earth by a plate being pulled
apart. Even more, it is oriented just as one would expect from plate
motions implied by the magnetic map.

"It's certainly not an exhaustive geologic analysis," said Dr. Mario
Acuña, principal investigator for the Mars Global Surveyor magnetic
filed investigation at Goddard Space Flight Center. "But plate tectonics
does give us a consistent explanation of some of the most prominent
features on Mars."

Results were published in the Oct. 10 edition of the Proceedings of the
National Academy of Science.

Other scientists working on the project included Dr. G. Kletetschka of
the Catholic University of America, Washington, DC, and Goddard Space
Flight Center; Dr. D.L. Mitchell and Dr. R.P. Lin of the University of
California at Berkeley; and Dr. H. Reme of the Centre d'Etude Spatiale
des Rayonnements in France. Dr. Acuña leads the international team that
built and operates the Mars Global Surveyor magnetometers. The Jet
Propulsion Laboratory, a division of the California Institute of
Technology in Pasadena, manages the mission for NASA's Science Mission
Directorate in Washington.

[NOTE: Images supporting this release are available at
http://www.nasa.gov/centers/goddard/...gs_plates.html ]

Robert Clark wrote:
See for example he

Plate Tectonics: The Mechanism.
http://www.ucmp.berkeley.edu/geology/tecmech.html

Sea floor spreading and magnetic striping stem from
basalt being formed at the ruptures in the oceanic
crust. Basalt is good for forming magnetic stripes,
but poor for sealing the ruptures in the crust.
Consequently, the spreading continues until the
water receeds and basalt formation ceases.
Water (under high pressure) is necessary for the
formation of basalt:
Si + 4H2O ---H4SiO4 (silicic acid) +2H2
H4SiO4 + 2Fe ---Fe2SiO4 (olivine) + 2H2
http://www.pmel.noaa.gov/vents/chemi...ges/vents2.gif
John Curtis

John Curtis wrote:
Robert Clark wrote:
See for example he

Plate Tectonics: The Mechanism.
http://www.ucmp.berkeley.edu/geology/tecmech.html

Sea floor spreading and magnetic striping stem from
basalt being formed at the ruptures in the oceanic
crust. Basalt is good for forming magnetic stripes,
but poor for sealing the ruptures in the crust.
Consequently, the spreading continues until the
water receeds and basalt formation ceases.
Water (under high pressure) is necessary for the
formation of basalt:
Si + 4H2O ---H4SiO4 (silicic acid) +2H2
H4SiO4 + 2Fe ---Fe2SiO4 (olivine) + 2H2
http://www.pmel.noaa.gov/vents/chemi...ges/vents2.gif
John Curtis

John, I thought a while back you were maintaining that the Earth had
its budget of water since the beginning, and that it covered the Earth
to great depth in the Archean (we had a difference where I referred to
the presence of conglomerates to refute that view). But if what you
say now is true (which supports the view of Expansion, that the
production of water is commensurate with the production of mantle) then
where is all the water that has accompanied the creation of the ocean
floors? That's an awwwful lot of water since the mesozoic. Where is
it all?