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Cited by 75Astro and Planetary ScienceGeological Studies and ExplorationGeological and Geochemical Analysis

The DOI matches its Crossref record; 52 of the 53 references it cites were found in a registry or an index; none of the 40 sources its claims cite is checked for support yet.

Tectonic influences on the morphometry of the Sudbury impact structure: Implications for terrestrial cratering and modeling

Open access
Spray, John G., Butler, Hadyn R., Thompson, Lucy M.·2004·Meteoritics & Planetary Science
DOI 10.1111/j.1945-5100.2004.tb00341.x
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Abstract

Abstract— Impact structures developed on active terrestrial planets (Earth and Venus) are susceptible to pre‐impact tectonic influences on their formation. This means that we cannot expect them to conform to ideal cratering models, which are commonly based on the response of a homogeneous target devoid of pre‐existing flaws. In the case of the 1.85 Ga Sudbury impact structure of Ontario, Canada, considerable influence has been exerted on modification stage processes by late Archean to early Proterozoic basement faults. Two trends are dominant: 1) the NNW‐striking Onaping Fault System, which is parallel to the 2.47 Ga Matachewan dyke swarm, and 2) the ENE‐striking Murray Fault System, which acted as a major Paleoproterozoic suture zone that contributed to the development of the Huronian sedimentary basin between 2.45–2.2 Ga. Sudbury has also been affected by syn‐ to post‐impact regional deformation and metamorphism: the 1.9–1.8 Ga Penokean orogeny, which involved NNW‐directed reverse faulting, uplift, and transpression at mainly greenschist facies grade, and the 1.16–0.99 Ga Grenville orogeny, which overprinted the SE sector of the impact structure to yield a polydeformed upper amphibolite facies terrain. The pre‐, syn‐, and post‐impact tectonics of the region have rendered the Sudbury structure a complicated feature. Careful reconstruction is required before its original morphometry can be established. This is likely to be true for many impact structures developed on active terrestrial planets. Based on extensive field work, combined with remote sensing and geophysical data, four ring systems have been identified at Sudbury. The inner three rings broadly correlate with pseudotachylyte (friction melt) ‐rich fault systems. The first ring has a diameter of ˜90 km and defines what is interpreted to be the remains of the central uplift. The second ring delimits the collapsed transient cavity diameter at ˜130 km and broadly corresponds to the original melt sheet diameter. The third ring has a diameter of ˜180 km. The fourth ring defines the suggested apparent crater diameter at ˜260 km. This approximates the final rim diameter, given that erosion in the North Range is <6 km and the ring faults are steeply dipping. Impact damage beyond Ring 4 may occur, but has not yet been identified in the field. One or more rings within the central uplift (Ring 1) may also exist. This form and concentric structure indicates that Sudbury is a peak ring or, more probably, a multi‐ring basin. These parameters provide the foundation for modeling the formation of this relatively large terrestrial impact structure.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

The 1.85 Ga Sudbury impact structure was strongly influenced by pre-existing basement faults and later overprinted by the Penokean and Grenville orogenies, so its original morphometry must be reconstructed. The authors identify four concentric ring systems and infer an apparent/final rim diameter of ~260 km, a collapsed transient cavity/melt sheet diameter of ~130 km, and a ~90 km central uplift.

Key findings

  • Four ring systems are identified from Landsat MSS lineaments and geophysics: Ring 1 at ~45 km radius (~90 km diameter, central uplift), Ring 2 at ~65 km radius (~130 km diameter, collapsed transient cavity and probable original melt sheet diameter), Ring 3 at ~90 km radius (~180 km diameter), and Ring 4 at ~130 km radius (~260 km diameter, apparent/final rim diameter).
  • Pre-impact fault systems controlled target structure: the NNW-striking Onaping Fault System is parallel to the 2.47 Ga Matachewan dyke swarm, and the ENE-striking Murray Fault System acted as a Paleoproterozoic suture zone linked to the Huronian basin; these formed a pre-existing fault grid reactivated during impact and post-impact adjustment.
  • E-type pseudotachylyte defines concentric ring systems, with enhanced zones at 25–35 km, 42–48 km, and 78–80 km beyond the Sudbury igneous complex; the South Range Breccia Belt is up to 1 km wide and 45 km long. S-type pseudotachylyte veins in the North Range occur typically every 50 cm, with individual offsets <2 mm, equivalent to total strain of 2 m per km of target rock.
  • The 2.47 Ga Matachewan dykes lose their magnetic signature at Ring 2, interpreted as shock demagnetization >1 GPa or thermal resetting above the Curie point; this supports a ~65 km radius for the demagnetized core and probable melt sheet. A ~130 km transient cavity corresponds to a projectile diameter of ~20 km for a 20 km/s impact using Schmidt and Housen (1987).

Methods

  • The study integrates extensive field work with remote sensing (Landsat multi-spectral scanning lineament analysis) and regional geophysical data, especially magnetic dyke distributions, to reconstruct Sudbury’s ring structure and morphometry.
  • Morphometric constraints come from final rim diameter estimates, maximum radial extent of melt sheet dykes (65 km), the demagnetized core zone, and concentric E-type pseudotachylyte-rich fault systems.
  • Calculated transient cavity, central uplift, and structural uplift dimensions are compared with terrestrial crater scaling relationships (Table 3), using a final rim diameter of 260 km.

Limitations

  • The paper states that Ring 4 has not been ground-truthed in the field, no definitive most distal impact-induced structural disturbance has been established, rock exposure is estimated at ~20% at best, and only ~30% of the region has been mapped at 1:30,000 scale.
  • The authors state that much morphometric information comes from rocks north of the Penokean Front, and that Penokean and Grenville overprinting makes reconstruction of the original crater form difficult in the South Range.
  • The text also makes evident that ring structures are recognized north of the Penokean Front but not definitively south of it, and that sparse terrestrial crater inventory limits understanding of central peak, peak ring, and multi-ring basin transitions on Earth.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1111/j.1945-5100.2004.tb00341.x

Cites

52 of 52 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

0 of 40 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Ring 1 has a diameter of ~90 km.

    “The first ring has a diameter of ~90 km”
    Quote in the paperSubstantial claim
  • Findingown data

    Based on extensive field work, combined with remote sensing and geophysical data, four ring systems have been identified at Sudbury.

    “Based on extensive field work, combined with remote sensing and geophysical data, four ring systems have been identified at Sudbury.”
    Quote in the paperSubstantial claim
  • Findingnone given

    The NNW-trending Onaping Fault System constitutes a major lineament set in the Sudbury region.

    “The NNW-trending Onaping Fault System constitutes a major lineament set in the Sudbury region (Fig. 2).”
    Quote in the paperSubstantial claim
  • Findingown data

    Ring 4 defines the suggested apparent crater diameter at ~260 km.

    “The fourth ring defines the suggested apparent crater diameter at ~260 km.”
    Quote in the paperSubstantial claim
  • Findingown data

    Ring 3 (East Bull Lake-Temagami ring) has a radius of 90 km.

    “Ring 3, the East Bull Lake-Temagami ring, is 90 km radius”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim. 13
  • It may state two separate claims as one. 39

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Findingnone given

    Impact damage beyond Ring 4 may occur, but has not yet been identified in the field.

    “Impact damage beyond Ring 4 may occur, but has not yet been identified in the field.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.

    Findingnone given

    The NNW-striking Onaping Fault System is parallel to the 2.47 Ga Matachewan dyke swarm.

    “the NNW-striking Onaping Fault System, which is parallel to the 2.47 Ga Matachewan dyke swarm”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingcitation

    The Murray Fault System has a WNW trend in the west, swinging to an ENE trend in the east, and an E and NE trend through the Sudbury basin, where it evolves to include the South Range Shear Zone.

    “The Murray Fault System has a WNW trend in the W of the region, swinging round to an ENE trend in the E, and an E and NE trend through the Sudbury basin, where it evolves to include the South Range Shear Zone (SRSZ in Fig. 2; Riller et al. 1998).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Riller et al. 1998 source

  • It may state two separate claims as one.

    Findingown data

    In the less deformed North Range, S-type veins typically occur every 50 cm and form a crude mesh, with individual offsets of <2 mm (equivalent to a total strain of 2 m per km of target rock).

    “In the less deformed and less faulted North Range, S-type veins typically occur every 50 cm and they form a crude mesh (at high angles to one another), with individual offsets of <2 mm (this is equivalent to a total strain of 2 m per km of target rock).”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingcitation

    Landsat MSS data reveals 4 main ring structures at Sudbury, labelled 1-4, with collective centers located just S of the SIC and W of the Copper Cliff offset dyke.

    “The Landsat data reveals 4 main ring structures, labelled 1-4 in Fig. 3, which have their collective centers located just S of the SIC and W of the Copper Cliff offset dyke.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Butler 1994

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one.

    Findingown data

    The four main ring structures are recognized north of the Penokean Front but not definitively south of it.

    “These are recognized N of the Penokean Front, but not definitively S of it (Fig. 7).”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingnone given

    The maximum established radius of the longest melt sheet dyke is 65 km, although this is not the proven end of the dyke.

    “The maximum established radius of the longest melt sheet dyke is 65 km, although this is not the proven end of the dyke.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingnone given

    Ring 1 coincides with the concentric Hess offset dyke in the North Range and certain large E-type pseudotachylyte bodies.

    “Ring 1 coincides with the concentric Hess offset dyke in the North Range and certain large Etype pseudotachylyte bodies.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    This 65 km radius approximately coincides with Ring 2 as defined by lineament imagery and E-type pseudotachylyte concentration, and with the limit of erased remnant magnetization in the 2.47 Ga Matachewan dykes.

    “This radius approximately coincides with Ring 2 as defined by lineament imagery and E-type pseudotachylyte concentration.It also coincides with the limit of erased remnant magnetization as seen in the 2.47 Ga Matachewan dykes (Fig. 4).”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingnone given

    The rings occur at radii from their projected center: Ring 1 at 45 km, Ring 2 at 65 km, Ring 3 at 90 km, and Ring 4 at 130 km.

    “The rings occur at the following radii from their projected center: Ring 1 at 45 km, Ring 2 at 65 km, Ring 3 at 90 km and Ring 4 at 130 km.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingcitation

    In the North Range, the annular trough coincides with downfaulted Huronian outliers and Archean greenstones, and with a change in strike and vertical offset in the Foy dyke.

    “In the North Range, this trough coincides with downfaulted Huronian outliers and Archean greenstones, and a change in strike and vertical offset in the Foy dyke (Tuchscherer and Spray 2002).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Tuchscherer and Spray 2002 source

  • It may state two separate claims as one.

    Findingnone given

    The core zone comprises a 90 km diameter central uplift and a surrounding 20 km-wide annular trough.

    “The core zone comprises a 90 km diameter central uplift and a surrounding 20 km-wide annular trough.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingnone given

    The central uplift is circular and bounded, at least in part, by a concentric zone of enhanced pseudotachylyte development.

    “The central uplift is circular and bounded, at least in part, by a concentric zone of enhanced pseudotachylyte development.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingreasoning

    The Matachewan dykes lose their magnetic signature on approaching Ring 2 and are magnetically 'invisible' within Ring 2.

    “The Matachewan dykes lose their magnetic signature on approaching Ring 2 and they are magnetically”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingnone given

    Within Ring 1, the rocks are pervaded by S-type pseudotachylytes and can be extensively shatter coned.

    “Within Ring 1 (i.e., within the area defined by an original radius of 45 km), the rocks are pervaded by S-type pseudotachylytes and the rocks can be extensively shatter coned.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationcitation

    This magnetic erasure places Ring 2 as a shock isobar of >1 GPa for the erasure of pre-existing remnant magnetization, or >10 GPa for the reduction of magnetic susceptibility.

    “This places Ring 2 as a shock isobar of >1 GPa for the erasure of pre-existing remnant magnetization, or >10 GPa for the reduction of magnetic susceptibility (Cisowski and Fuller 1978).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Cisowski and Fuller 1978 source

  • Probably not a substantial claim. It may state two separate claims as one.

    Premisenone given

    The 1.85 Ga Sudbury impact event affected an already complicated tectonic region, and the structure now straddles the present-day erosional boundaries between three different Precambrian provinces.

    “The 1.85 Ga Sudbury impact event affected an already complicated tectonic region and the structure now straddles the present day erosional boundaries between three different Precambrian provinces.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The Sudbury impact occurred at 1.85 Ga.

  • It may state two separate claims as one.

    Interpretationnone given

    This fault mesh did not appear to facilitate syn-impact wrench movement, but probably accommodated mainly vertical displacements beneath the evolving impact structure.

    “This fault mesh did not appear to facilitate syn-impact wrench movement, but probably accommodated mainly vertical displacements beneath the evolving impact structure.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. It may be too vague to check against evidence.

    Interpretationreasoning

    Careful reconstruction is required before Sudbury's original morphometry can be established.

    “Careful reconstruction is required before its original morphometry can be established.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationnone given

    At Sudbury, the inner S-type pseudotachylyte-rich zone correlates with the central uplift, the boundaries of which are marked in the North Range by the Hess Offset.

    “At Sudbury, we correlate this inner S-type pseudotachylyte-rich zone with the central uplift (discussed later), the boundaries of which are marked in the North Range by the Hess Offset (Fig. 1).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper may give no reason why it holds. It may state two separate claims as one.

    Premisenone given

    Hypervelocity impact occurred at 1.85 Ga into a continental margin terrain that was actively undergoing late stage deformation and metamorphism as part of the Penokean orogeny.

    “Hypervelocity impact occurred at 1.85 Ga into a continental margin terrain that was actively undergoing late stage deformation and metamorphism as part of the Penokean orogeny (Table 1).”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The Sudbury impact occurred at 1.85 Ga.

  • Probably not a substantial claim. It may be too vague to check against evidence. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.

    Interpretationreasoning

    This need for careful reconstruction is likely true for many impact structures developed on active terrestrial planets.

    “This is likely to be true for many impact structures developed on active terrestrial planets.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    Ideal cratering models are commonly based on the response of a homogeneous target devoid of pre-existing flaws, so impact structures on active planets cannot be expected to conform to them.

    “This means that we cannot expect them to conform to ideal cratering models, which are commonly based on the response of a homogeneous target devoid of pre-existing flaws.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    Pseudotachylyte at Sudbury has been used as an indicator of crater dimensions.

    “Pseudotachylyte occurs throughout the Sudbury structure and it has been used as an indicator of crater dimensions (Spray and Thompson 1995) .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Spray and Thompson 1995 source

  • It may state two separate claims as one.

    Interpretationreasoning

    The Onaping faults are generally straight, indicating a high angle disposition.

    “The Onaping faults are generally straight, indicating a high angle disposition.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Premisecitation

    E-type pseudotachylyte post-dates S-type pseudotachylyte and generally forms veins >1 cm thick, up to dyke-like bodies 1 km wide.

    “E-type pseudotachylyte post-dates S-type pseudotachylyte, and generally forms veins >1 cm thick, up to spectacular dyke-like bodies 1 km wide (Spray 1998b).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Spray 1998b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one.

    Interpretationreasoning

    Most of the displacement on the Onaping faults is pre-impact, and the faults are not responsible for causing major post-impact deformation of the Sudbury structure.

    “Most of the displacement on these faults is pre-impact, and the faults are not responsible for causing major post-impact deformation of the Sudbury structure.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisenone given

    E-type pseudotachylyte is formed by frictional melting during the modification stage of the impact process in response to gravity driven processes.

    “E-type pseudotachylyte is formed by frictional melting during the modification stage of the impact process in response to gravity driven processes.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    The form and concentric structure of Sudbury indicates that it is a peak ring or, more probably, a multi-ring basin.

    “This form and concentric structure indicates that Sudbury is a peak ring or, more probably, a multi-ring basin.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    The apparent crater diameter (~260 km) approximates the final rim diameter, given that erosion in the North Range is <6 km and the ring faults are steeply dipping.

    “This approximates the final rim diameter, given that erosion in the North Range is <6 km and the ring faults are steeply dipping.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Thompson et al. 1998 source

  • It may state two separate claims as one.

    Premisecitation

    The 1.9-1.8 Ga Penokean orogeny involved NNW-directed reverse faulting, uplift, and transpression at mainly greenschist facies grade at Sudbury.

    “the 1.9-1.8Ga Penokean orogeny, which involved NNW-directed reverse faulting, uplift, and transpression at mainly greenschist facies grade”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Riller et al. 1999

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one.

    Premisecitation

    The 1.85 Ga Sudbury structure is one of the largest impact structures on Earth, comparable in size to the 2.02 Ga Vredefort structure (~300 km diameter).

    “The 1.85 Ga Sudbury structure is now recognized as one of the largest impact structures on Earth, comparable in size to the 2.02 Ga Vredefort structure of South Africa (~300 km diameter, based on the maximum radius of damage; Therriault et al. 1997).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Therriault et al. 1997 source
    • Rests on an assumption: The Sudbury impact occurred at 1.85 Ga.

  • It may state two separate claims as one.

    Premisenone given

    More intense faulting and metamorphism in the South Range makes its reconstruction difficult, while the North Range is less deformed and less altered by post-impact processes.

    “More intense faulting and metamorphism in the South Range makes its reconstruction in the southern sector difficult, while the North Range is less deformed and less altered by postimpact processes.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    Sudbury contains the largest known pseudotachylyte body: the South Range Breccia Belt, which is up to 1 km wide and 45 km long.

    “Sudbury contains the largest known pseudotachylyte body: the South Range Breccia Belt, which is up to 1 km wide and 45 km long (Spray 1997;Scott andSpray 1999, 2000).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Spray 1997

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Scott and Spray 1999, 2000

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one.

    Interpretationnone given

    The Onaping Fault System was probably initiated in the late Archean and was active by early Proterozoic times.

    “Overall, the Onaping Fault System was probably initiated in the late Archean, and was active by early Proterozoic times.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    The Sudbury impact structure affected a target area of at least 53,000 km2, given that damage effects may extend beyond the final rim.

    “This means that the Sudbury impact structure probably had a final rim diameter of ~260 km, and so affected a target area of at least 53,000 km 2 , given that damage effects may extend beyond the final rim.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    The Late Penokean orogeny involved greenschist to sub-greenschist facies.

    “Greenschist to sub-greenschist facies”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Holm et al. (2001)

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one.

    Interpretationnone given

    Ring 4 is the furthest recognizable feature found to date associated with the Sudbury impact structure, and it represents the apparent crater diameter.

    “Given that Ring 4 is the furthest recognizable feature found to date associated with the Sudbury impact structure, we take this to represent the apparent crater diameter.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Premisenone given

    The main effects of the Penokean orogeny are felt in the South Range, where NNW-directed reverse faulting generated the South Range Shear Zone.

    “The main effects of the Penokean are felt in the South Range, where NNW-directed reverse faulting generated the South Range Shear Zone (SRSZ of Fig. 2).”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Premisecitation

    During the later stages of the Penokean orogeny, the Murray Fault acted as a dextral transpressive system in its western sector and, to a lesser degree, with the same sense in its eastern sector.

    “Correlation of the Murray Fault System with the Great Lakes tectonic zone to the W (Sims et al. 1980) indicates that, during the later stages of the Penokean orogeny, the Murray Fault acted as a dextral transpressive system in its western sector and, to a lesser degree, with the same sense in its eastern sector.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Sims et al. 1980

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • It may state two separate claims as one.

    Interpretationreasoning

    The demagnetization requires shock pressures >1 GPa, or thermal resetting above the Curie point of the magnetic phase(s).

    “This requires shock pressures >1 GPa, or thermal resetting above the Curie point of the magnetic phase(s).”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Premisereasoning

    Grenville deformation resulted in NW-directed reverse faulting and folding in the SE sector, and limited reactivation of pre-existing fault systems NW of the Grenville Front.

    “Grenville deformation resulted in NW-directed reverse faulting and folding in the SE sector, and limited reactivation of pre-existing fault systems NW of the Grenville Front.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    Sudbury has an apparent crater diameter of ~260 km, with a comparable final rim diameter.

    “The above evidence suggests that Sudbury has an apparent crater diameter of ~260 km (with a comparable final rim diameter) and a melt sheet diameter of ~130 km.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationcitation

    The apparent crater diameter is approximately coincident with the final rim diameter Dfr, because erosion in the North Range since impact is relatively minor (<6 km) and the concentric fault systems appear to dip steeply.

    “Because the amount of erosion in the North Range since impact is relatively minor (<6 km; Thompson et al. 1998), and because the concentric fault systems appear to dip steeply, we suggest that the apparent crater diameter is approximately coincident with the final rim diameter D fr .”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Thompson et al. 1998 source

  • It may state two separate claims as one.

    Interpretationreasoning

    North of the Penokean Front, the ring structures have not undergone major offset by post-impact deformation, indicating that post-1.85 Ga wrench faulting was not significant (<<1 km) within the North Range.

    “North of the Penokean Front, the ring structures have not undergone major offset by post-impact deformation, which indicates that post-1.85Ga wrench faulting was not significant (i.e., <<1 km) within the North Range.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    The fault blocks were active during postimpact isostatic adjustment, especially along the pre-impact Penokean mountain front in the South Range and a transverse Penokean belt in the East Range, where gravity-driven adjustments were protracted even as the melt sheet cooled.

    “These were active during postimpact isostatic adjustment of the impact structure, especially along the pre-impact Penokean mountain front in the South Range and a transverse Penokean belt in the East Range, where gravity driven adjustments were protracted, even as the melt sheet cooled (as indicated by multiple intrusive relations between the SIC components).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper may give no reason why it holds.

    Interpretationnone given

    For Sudbury, high-angle NNW (Onaping type) and ENE (Murray type) lineament sets may have been coupled as a pre-existing fault grid that should be built in as flaws in target reconstructions.

    “For Sudbury, highangle NNW (Onaping type) and ENE (Murray type) lineament sets may have been coupled as a pre-existing fault grid that should be built in as flaws in target reconstructions.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper may give no reason why it holds.

    Interpretationnone given

    For many impact structures, pre-existing structural grain and synimpact strain fields in the target rocks may be important in controlling the cratering process.

    “For many impact structures, pre-existing structural grain and synimpact strain fields in the target rocks may be important in controlling the cratering process.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.

    Interpretationnone given

    The inward movement of pie-shaped blocks requires them to locally overlap and form transpression zones.

    “The inward movement of pie-shaped blocks requires them to locally overlap and form transpression zones.”
    Quote in the paperNot a substantial claim
49 of 49

  • The authors state this as an assumption.

    Melt sheet dykes were fed vertically from above, at least in their more distal portions.

    “assuming that melt sheet dykes were fed vertically from above, at least in their more distal portions”

  • The paper relies on this without support.

    The Sudbury impact occurred at 1.85 Ga.

    “The 1.85 Ga Sudbury impact structure”

  • The paper relies on this without support.

    The Murray Fault System represents the tectonic front of the Penokean orogen and cuts through the center of the Sudbury basin as the South Range Shear Zone.

    “The Murray Fault System is considered to represent the tectonic front of the Penokean orogen, and this cuts through the center of the Sudbury basin as the South Range Shear Zone.”

  • The paper relies on this without support.

    The Onaping and Murray Fault Systems are basement lineaments that controlled continental margin tectonics during late Archean to Paleoproterozoic times.

    “The Onaping and Murray Fault Systems are basement lineaments that controlled continental margin tectonics during late Archean to Paleoproterozoic times.”

  • The paper relies on this without support.

    The Penokean strain field involved NNW-directed compression and was active at the time of the Sudbury impact.

    “The Penokean strain field involved a NNW-directed compression and was active at the time of impact.”

  • The paper relies on this without support.

    The four main ring structures identified by lineament analysis are genetically related to the Sudbury impact event.

    “Lineament analysis, based on Landsat MSS data and regional geophysics, indicates the presence of four main ring structures.”
6 of 6

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Conflicting year for the Shand reference

    Minor

    The discussion cites Shand (1914) for pseudotachylyte at Vredefort, but the Shand work listed in the references is dated 1916.

  • Conflicting year for the Corfu and Andrews reference

    Minor

    The Nipissing diabase entry cites Corfu and Andrews (1980), while the paper's reference list gives their cited work as published in 1986. The prose also cites 1986 for the Nipissing diabase age.

2 of 2

Citations

Cites

Flagged first, then by citations

1 of the 53 references couldn’t be matched to a known paper.

Research works printed but not linked: 19

  1. Low Bar N. G.2000.Updates toThe catalog of large martian impact craters(abstract #1475). 31st Lunar and Planetary Science Conference. CD‐ROM.
  2. Bennett G., 1991, Geology of Ontario, 549
  3. Dence M. R., 1972, Evidence for an impact origin for Lake Wanapitei, Ontario, 117
  4. Easton R. M., 1992, Geology of Ontario., 713
  5. Easton R. M., 2002, Precambrian geology of Street Township, Southern and Grenville Provinces, 149
  6. Frarey M. J., 1982, Rb‐Sr and U‐Pb isotopic age studies, report 5, current research, part C., 129
  7. French B. M., 1998, Traces of catastrophe, 120
  8. Grant R. W., 1984, The geology and ore deposits of the Sudbury structure, 275
  9. Grieve R. A. F., 1996, The signature of terrestrial impacts, Journal of Australian Geology and Geophysics, 16, 399
  10. Grieve R. A. F., 1981, Multi‐ring basins, 37
  11. Holm D. K., 2001, Direct timing constraints on Paleoproterozoic metamorphism, southern Lake Superior region: Results from SHRIMP and EMP U‐Pb dating of metamorphic monazites (abstract), GSA Abstracts with Programs, 33, A401
  12. Jackson S. L., 1991, Geology of Ontario, 405
  13. KroghT. E.1989.Terrane identification in the Grenville Province from detrital and metamorphic zircon ages. InThe Abitibi Grenville Lithoprobe Project 1989 Transect report and updated Proposal.pp.63–65.
  14. Krogh T. E., 1984, The geology and ore deposits of the Sudbury structure, 431
  15. Krogh T. E., 1987, Mafic dyke swarms, 147
  16. PikeR. J.1980.Control of crater morphology by gravity and target type: Mars Earth Moon. Proceedings 11th Lunar and Planetary Science Conference. pp.2159–2189.
  17. 10.1130/0091-7613(1997)025 · DOI
  18. Sutcliffe R. H., 1991, Geology of Ontario, 627
  19. Thompson L. M., 1994, Large meteorite impacts and planetary evolution, 275

Cited by

Sorted by citations

Related

Metadata

Authors
Spray, J. G., Butler, H. R., & Thompson, L. M.
Affiliations
University of New Brunswick (CA)
Corresponding author
Spray, John G.
ORCID
Venue
Meteoritics & Planetary Science
Publisher
Wiley
Published
2004-02
Volume
39
Issue
2
Pages
287-301
ISSN
  • 1086-9379 (ISSN-L)
  • 1945-5100
DOI
10.1111/j.1945-5100.2004.tb00341.x
OpenAlex
W2037949447
Cited by
75
References
53
Citations by year
2026: 2 · 2025: 1 · 2024: 1 · 2022: 5 · 2021: 3 · 2020: 5 · 2019: 2 · 2018: 4 · 2017: 3 · 2016: 1 · 2015: 3 · 2014: 4 · 2013: 1 · 2012: 3
FWCI
4.37
Type
journal article
Language
en
Open access
Licence
onlinelibrary.wiley.com/termsAndConditions#vor (vor, 2186 d)
Locations
  • Meteoritics and Planetary Science (publishedVersion)
  • UA Campus Repository (The University of Arizona) (acceptedVersion)
Funders
Natural Sciences and Engineering Research Council of Canada
Topics
  • Physical Sciences › Earth and Planetary Sciences › Space and Planetary Science › Astro and Planetary Science
  • Physical Sciences › Earth and Planetary Sciences › Geology › Geological Studies and Exploration
  • Physical Sciences › Earth and Planetary Sciences › Geochemistry and Petrology › Geological and Geochemical Analysis
Keywords
Sudbury impact structure, basement faults, Penokean orogeny, Grenville orogeny, ring systems, central uplift, transient cavity, pseudotachylyte, ring faults, impact cratering

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

A language model drew the claims from the paper on 2026-11-10, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).

A second model labelled each claim on 2026-11-10 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

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