Abstract
The Shallow Radar (SHARAD) on the Mars Reconnaissance Orbiter has imaged the internal stratigraphy of the north polar layered deposits of Mars. Radar reflections within the deposits reveal a laterally continuous deposition of layers, which typically consist of four packets of finely spaced reflectors separated by homogeneous interpacket regions of nearly pure ice. The packet/interpacket structure can be explained by approximately million-year periodicities in Mars' obliquity or orbital eccentricity. The observed ∼100-meter maximum deflection of the underlying substrate in response to the ice load implies that the present-day thickness of an equilibrium elastic lithosphere is greater than 300 kilometers. Alternatively, the response to the load may be in a transient state controlled by mantle viscosity. Both scenarios probably require that Mars has a subchondritic abundance of heat-producing elements.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1182-1185 |
| Number of pages | 4 |
| Journal | Science |
| Volume | 320 |
| Issue number | 5880 |
| DOIs | |
| State | Published - May 30 2008 |
| Externally published | Yes |
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ASJC Scopus subject areas
- General
Cite this
Mars north polar deposits : stratigraphy, age, and geodynamical response. / Phillips, Roger J.; Zuber, Maria T.; Smrekar, Suzanne E.; Mellon, Michael T.; Head, James W.; Tanaka, Kenneth L.; Putzig, Nathaniel E.; Milkovich, Sarah M.; Campbell, Bruce A.; Plaut, Jeffrey J.; Safaeinili, Ali; Seu, Roberto; Biccari, Daniela; Carter, Lynn M.; Picardi, Giovanni; Orosei, Roberto; Surdas Mohit, P.; Heggy, Essam; Zurek, Richard W.; Egan, Anthony F.; Giacomoni, Emanuele; Russo, Federica; Cutigni, Marco; Pettinelli, Elena; Holt, John W.; Leuschen, Carl J.; Marinangeli, Lucia.
In: Science, Vol. 320, No. 5880, 30.05.2008, p. 1182-1185.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Mars north polar deposits
T2 - stratigraphy, age, and geodynamical response
AU - Phillips, Roger J.
AU - Zuber, Maria T.
AU - Smrekar, Suzanne E.
AU - Mellon, Michael T.
AU - Head, James W.
AU - Tanaka, Kenneth L.
AU - Putzig, Nathaniel E.
AU - Milkovich, Sarah M.
AU - Campbell, Bruce A.
AU - Plaut, Jeffrey J.
AU - Safaeinili, Ali
AU - Seu, Roberto
AU - Biccari, Daniela
AU - Carter, Lynn M.
AU - Picardi, Giovanni
AU - Orosei, Roberto
AU - Surdas Mohit, P.
AU - Heggy, Essam
AU - Zurek, Richard W.
AU - Egan, Anthony F.
AU - Giacomoni, Emanuele
AU - Russo, Federica
AU - Cutigni, Marco
AU - Pettinelli, Elena
AU - Holt, John W.
AU - Leuschen, Carl J.
AU - Marinangeli, Lucia
PY - 2008/5/30
Y1 - 2008/5/30
N2 - The Shallow Radar (SHARAD) on the Mars Reconnaissance Orbiter has imaged the internal stratigraphy of the north polar layered deposits of Mars. Radar reflections within the deposits reveal a laterally continuous deposition of layers, which typically consist of four packets of finely spaced reflectors separated by homogeneous interpacket regions of nearly pure ice. The packet/interpacket structure can be explained by approximately million-year periodicities in Mars' obliquity or orbital eccentricity. The observed ∼100-meter maximum deflection of the underlying substrate in response to the ice load implies that the present-day thickness of an equilibrium elastic lithosphere is greater than 300 kilometers. Alternatively, the response to the load may be in a transient state controlled by mantle viscosity. Both scenarios probably require that Mars has a subchondritic abundance of heat-producing elements.
AB - The Shallow Radar (SHARAD) on the Mars Reconnaissance Orbiter has imaged the internal stratigraphy of the north polar layered deposits of Mars. Radar reflections within the deposits reveal a laterally continuous deposition of layers, which typically consist of four packets of finely spaced reflectors separated by homogeneous interpacket regions of nearly pure ice. The packet/interpacket structure can be explained by approximately million-year periodicities in Mars' obliquity or orbital eccentricity. The observed ∼100-meter maximum deflection of the underlying substrate in response to the ice load implies that the present-day thickness of an equilibrium elastic lithosphere is greater than 300 kilometers. Alternatively, the response to the load may be in a transient state controlled by mantle viscosity. Both scenarios probably require that Mars has a subchondritic abundance of heat-producing elements.
UR - http://www.scopus.com/inward/record.url?scp=46449139465&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=46449139465&partnerID=8YFLogxK
U2 - 10.1126/science.1157546
DO - 10.1126/science.1157546
M3 - Article
C2 - 18483402
AN - SCOPUS:46449139465
VL - 320
SP - 1182
EP - 1185
JO - Science
JF - Science
SN - 0036-8075
IS - 5880
ER -