Origin of the structure and planform of small impact craters in fractured targets

Endurance Crater at Meridiani Planum, Mars

Wesley A. Watters, John P. Grotzinger, James Bell, John Grant, Alex G. Hayes, Rongxing Li, Steven W. Squyres, Maria T. Zuber

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

We present observations and models that together explain many hallmarks of the structure and growth of small impact craters forming in targets with aligned fractures. Endurance Crater at Meridiani Planum on Mars (diameter ≈ 150. m) formed in horizontally-layered aeolian sandstones with a prominent set of wide, orthogonal joints. A structural model of Endurance Crater is assembled and used to estimate the transient crater planform. The model is based on observations from the Mars Exploration Rover Opportunity: (a) bedding plane orientations and layer thicknesses measured from stereo image pairs; (b) a digital elevation model of the whole crater at 0.3. m resolution; and (c) color image panoramas of the upper crater walls. This model implies that the crater's current shape was mostly determined by highly asymmetric excavation rather than long-term wind-mediated erosion. We show that modal azimuths of conjugate fractures in the surrounding rocks are aligned with the square component of the present-day crater planform, suggesting excavation was carried farther in the direction of fracture alignments. This was previously observed at Barringer Crater in Arizona and we show the same relationship also holds for Tswaing Crater in South Africa. We present models of crater growth in which excavation creates a " stellate" transient cavity that is concave-cuspate in planform. These models reproduce the " lenticular-crescentic" layering pattern in the walls of some polygonal impact craters such as Endurance and Barringer Craters, and suggest a common origin for tear faults and some crater rays. We also demonstrate a method for detailed error analysis of stereogrammetric measurements of bedding plane orientations.

Original languageEnglish (US)
Pages (from-to)472-497
Number of pages26
JournalIcarus
Volume211
Issue number1
DOIs
StatePublished - Jan 2011
Externally publishedYes

Fingerprint

planforms
endurance
craters
mars
crater
Mars
excavation
bedding plane
wind erosion
Mars exploration
stereo image
digital elevation models
Republic of South Africa
error analysis
sandstones

Keywords

  • Geological processes
  • Impact processes
  • Mars, Surface

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Origin of the structure and planform of small impact craters in fractured targets : Endurance Crater at Meridiani Planum, Mars. / Watters, Wesley A.; Grotzinger, John P.; Bell, James; Grant, John; Hayes, Alex G.; Li, Rongxing; Squyres, Steven W.; Zuber, Maria T.

In: Icarus, Vol. 211, No. 1, 01.2011, p. 472-497.

Research output: Contribution to journalArticle

Watters, WA, Grotzinger, JP, Bell, J, Grant, J, Hayes, AG, Li, R, Squyres, SW & Zuber, MT 2011, 'Origin of the structure and planform of small impact craters in fractured targets: Endurance Crater at Meridiani Planum, Mars', Icarus, vol. 211, no. 1, pp. 472-497. https://doi.org/10.1016/j.icarus.2010.08.030
Watters, Wesley A. ; Grotzinger, John P. ; Bell, James ; Grant, John ; Hayes, Alex G. ; Li, Rongxing ; Squyres, Steven W. ; Zuber, Maria T. / Origin of the structure and planform of small impact craters in fractured targets : Endurance Crater at Meridiani Planum, Mars. In: Icarus. 2011 ; Vol. 211, No. 1. pp. 472-497.
@article{f5c0b3549cb8438c8988f3c28abe36f2,
title = "Origin of the structure and planform of small impact craters in fractured targets: Endurance Crater at Meridiani Planum, Mars",
abstract = "We present observations and models that together explain many hallmarks of the structure and growth of small impact craters forming in targets with aligned fractures. Endurance Crater at Meridiani Planum on Mars (diameter ≈ 150. m) formed in horizontally-layered aeolian sandstones with a prominent set of wide, orthogonal joints. A structural model of Endurance Crater is assembled and used to estimate the transient crater planform. The model is based on observations from the Mars Exploration Rover Opportunity: (a) bedding plane orientations and layer thicknesses measured from stereo image pairs; (b) a digital elevation model of the whole crater at 0.3. m resolution; and (c) color image panoramas of the upper crater walls. This model implies that the crater's current shape was mostly determined by highly asymmetric excavation rather than long-term wind-mediated erosion. We show that modal azimuths of conjugate fractures in the surrounding rocks are aligned with the square component of the present-day crater planform, suggesting excavation was carried farther in the direction of fracture alignments. This was previously observed at Barringer Crater in Arizona and we show the same relationship also holds for Tswaing Crater in South Africa. We present models of crater growth in which excavation creates a {"} stellate{"} transient cavity that is concave-cuspate in planform. These models reproduce the {"} lenticular-crescentic{"} layering pattern in the walls of some polygonal impact craters such as Endurance and Barringer Craters, and suggest a common origin for tear faults and some crater rays. We also demonstrate a method for detailed error analysis of stereogrammetric measurements of bedding plane orientations.",
keywords = "Geological processes, Impact processes, Mars, Surface",
author = "Watters, {Wesley A.} and Grotzinger, {John P.} and James Bell and John Grant and Hayes, {Alex G.} and Rongxing Li and Squyres, {Steven W.} and Zuber, {Maria T.}",
year = "2011",
month = "1",
doi = "10.1016/j.icarus.2010.08.030",
language = "English (US)",
volume = "211",
pages = "472--497",
journal = "Icarus",
issn = "0019-1035",
publisher = "Academic Press Inc.",
number = "1",

}

TY - JOUR

T1 - Origin of the structure and planform of small impact craters in fractured targets

T2 - Endurance Crater at Meridiani Planum, Mars

AU - Watters, Wesley A.

AU - Grotzinger, John P.

AU - Bell, James

AU - Grant, John

AU - Hayes, Alex G.

AU - Li, Rongxing

AU - Squyres, Steven W.

AU - Zuber, Maria T.

PY - 2011/1

Y1 - 2011/1

N2 - We present observations and models that together explain many hallmarks of the structure and growth of small impact craters forming in targets with aligned fractures. Endurance Crater at Meridiani Planum on Mars (diameter ≈ 150. m) formed in horizontally-layered aeolian sandstones with a prominent set of wide, orthogonal joints. A structural model of Endurance Crater is assembled and used to estimate the transient crater planform. The model is based on observations from the Mars Exploration Rover Opportunity: (a) bedding plane orientations and layer thicknesses measured from stereo image pairs; (b) a digital elevation model of the whole crater at 0.3. m resolution; and (c) color image panoramas of the upper crater walls. This model implies that the crater's current shape was mostly determined by highly asymmetric excavation rather than long-term wind-mediated erosion. We show that modal azimuths of conjugate fractures in the surrounding rocks are aligned with the square component of the present-day crater planform, suggesting excavation was carried farther in the direction of fracture alignments. This was previously observed at Barringer Crater in Arizona and we show the same relationship also holds for Tswaing Crater in South Africa. We present models of crater growth in which excavation creates a " stellate" transient cavity that is concave-cuspate in planform. These models reproduce the " lenticular-crescentic" layering pattern in the walls of some polygonal impact craters such as Endurance and Barringer Craters, and suggest a common origin for tear faults and some crater rays. We also demonstrate a method for detailed error analysis of stereogrammetric measurements of bedding plane orientations.

AB - We present observations and models that together explain many hallmarks of the structure and growth of small impact craters forming in targets with aligned fractures. Endurance Crater at Meridiani Planum on Mars (diameter ≈ 150. m) formed in horizontally-layered aeolian sandstones with a prominent set of wide, orthogonal joints. A structural model of Endurance Crater is assembled and used to estimate the transient crater planform. The model is based on observations from the Mars Exploration Rover Opportunity: (a) bedding plane orientations and layer thicknesses measured from stereo image pairs; (b) a digital elevation model of the whole crater at 0.3. m resolution; and (c) color image panoramas of the upper crater walls. This model implies that the crater's current shape was mostly determined by highly asymmetric excavation rather than long-term wind-mediated erosion. We show that modal azimuths of conjugate fractures in the surrounding rocks are aligned with the square component of the present-day crater planform, suggesting excavation was carried farther in the direction of fracture alignments. This was previously observed at Barringer Crater in Arizona and we show the same relationship also holds for Tswaing Crater in South Africa. We present models of crater growth in which excavation creates a " stellate" transient cavity that is concave-cuspate in planform. These models reproduce the " lenticular-crescentic" layering pattern in the walls of some polygonal impact craters such as Endurance and Barringer Craters, and suggest a common origin for tear faults and some crater rays. We also demonstrate a method for detailed error analysis of stereogrammetric measurements of bedding plane orientations.

KW - Geological processes

KW - Impact processes

KW - Mars, Surface

UR - http://www.scopus.com/inward/record.url?scp=78650956777&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=78650956777&partnerID=8YFLogxK

U2 - 10.1016/j.icarus.2010.08.030

DO - 10.1016/j.icarus.2010.08.030

M3 - Article

VL - 211

SP - 472

EP - 497

JO - Icarus

JF - Icarus

SN - 0019-1035

IS - 1

ER -