Identification and significance of ice-flow-transverse subglacial ridges (Rogen moraines) in northern central Ireland

J Knight, AM McCabe

    Research output: Contribution to journalArticle

    53 Citations (Scopus)

    Abstract

    In the Omagh Basin, north central Ireland, subglacial diamict ridges lie transverse to southwestward Late Devensian (ca. 23-13 ka) ice flow. These ridges (0.5-2.5 km long, 100-450 m wide, 15-35 m high), are similar morphologically to Rogen moraines, which have not been described previously from the British Isles. The crests of some transverse ridges are streamlined, cross-cut or overprinted by drumlins, whereas other ridges are unmodified and were not affected by later drumlinisation. At Kilskeery, west-east trending eskers overlying unmodified transverse ridges post-date drumlinisation (17-14 C-14 ka). Esker formation shows that the subglacial thermal regime changed from cold-based, favouring bedform preservation, to warm-based with meltwater flowing through enclosed subglacial channels. Patterns of flow-transverse-ridges and spatial variations in the degree of bedform modification record dynamic changes in regional subglacial environments during the last deglacial cycle. This ice-mass variability cannot be reconciled with current Irish glacial models, which are based on immobile ice centres and ordered stages of ice retreat. In a wider context, these changes in bedform patterns and basal ice regimes have a similar signature to millennial-scale ice-mass oscillations recorded by dated proxy evidence elsewhere in the amphi-North Atlantic.
    LanguageEnglish
    Pages519-524
    JournalJournal of Quaternary Science
    Volume12
    Issue number6
    DOIs
    Publication statusPublished - Nov 1997

    Fingerprint

    ice flow
    bedform
    ice
    subglacial environment
    esker
    basal ice
    drumlin
    ice retreat
    Devensian
    thermal regime
    meltwater
    spatial variation
    oscillation
    basin

    Cite this

    @article{230529ffab1e4dffaae33705d192ae58,
    title = "Identification and significance of ice-flow-transverse subglacial ridges (Rogen moraines) in northern central Ireland",
    abstract = "In the Omagh Basin, north central Ireland, subglacial diamict ridges lie transverse to southwestward Late Devensian (ca. 23-13 ka) ice flow. These ridges (0.5-2.5 km long, 100-450 m wide, 15-35 m high), are similar morphologically to Rogen moraines, which have not been described previously from the British Isles. The crests of some transverse ridges are streamlined, cross-cut or overprinted by drumlins, whereas other ridges are unmodified and were not affected by later drumlinisation. At Kilskeery, west-east trending eskers overlying unmodified transverse ridges post-date drumlinisation (17-14 C-14 ka). Esker formation shows that the subglacial thermal regime changed from cold-based, favouring bedform preservation, to warm-based with meltwater flowing through enclosed subglacial channels. Patterns of flow-transverse-ridges and spatial variations in the degree of bedform modification record dynamic changes in regional subglacial environments during the last deglacial cycle. This ice-mass variability cannot be reconciled with current Irish glacial models, which are based on immobile ice centres and ordered stages of ice retreat. In a wider context, these changes in bedform patterns and basal ice regimes have a similar signature to millennial-scale ice-mass oscillations recorded by dated proxy evidence elsewhere in the amphi-North Atlantic.",
    author = "J Knight and AM McCabe",
    year = "1997",
    month = "11",
    doi = "10.1002/(SICI)1099-1417(199711/12)12:6<519::AID-JQS313>3.0.CO;2-Q",
    language = "English",
    volume = "12",
    pages = "519--524",
    journal = "Journal of Quaternary Science",
    issn = "0267-8179",
    number = "6",

    }

    Identification and significance of ice-flow-transverse subglacial ridges (Rogen moraines) in northern central Ireland. / Knight, J; McCabe, AM.

    In: Journal of Quaternary Science, Vol. 12, No. 6, 11.1997, p. 519-524.

    Research output: Contribution to journalArticle

    TY - JOUR

    T1 - Identification and significance of ice-flow-transverse subglacial ridges (Rogen moraines) in northern central Ireland

    AU - Knight, J

    AU - McCabe, AM

    PY - 1997/11

    Y1 - 1997/11

    N2 - In the Omagh Basin, north central Ireland, subglacial diamict ridges lie transverse to southwestward Late Devensian (ca. 23-13 ka) ice flow. These ridges (0.5-2.5 km long, 100-450 m wide, 15-35 m high), are similar morphologically to Rogen moraines, which have not been described previously from the British Isles. The crests of some transverse ridges are streamlined, cross-cut or overprinted by drumlins, whereas other ridges are unmodified and were not affected by later drumlinisation. At Kilskeery, west-east trending eskers overlying unmodified transverse ridges post-date drumlinisation (17-14 C-14 ka). Esker formation shows that the subglacial thermal regime changed from cold-based, favouring bedform preservation, to warm-based with meltwater flowing through enclosed subglacial channels. Patterns of flow-transverse-ridges and spatial variations in the degree of bedform modification record dynamic changes in regional subglacial environments during the last deglacial cycle. This ice-mass variability cannot be reconciled with current Irish glacial models, which are based on immobile ice centres and ordered stages of ice retreat. In a wider context, these changes in bedform patterns and basal ice regimes have a similar signature to millennial-scale ice-mass oscillations recorded by dated proxy evidence elsewhere in the amphi-North Atlantic.

    AB - In the Omagh Basin, north central Ireland, subglacial diamict ridges lie transverse to southwestward Late Devensian (ca. 23-13 ka) ice flow. These ridges (0.5-2.5 km long, 100-450 m wide, 15-35 m high), are similar morphologically to Rogen moraines, which have not been described previously from the British Isles. The crests of some transverse ridges are streamlined, cross-cut or overprinted by drumlins, whereas other ridges are unmodified and were not affected by later drumlinisation. At Kilskeery, west-east trending eskers overlying unmodified transverse ridges post-date drumlinisation (17-14 C-14 ka). Esker formation shows that the subglacial thermal regime changed from cold-based, favouring bedform preservation, to warm-based with meltwater flowing through enclosed subglacial channels. Patterns of flow-transverse-ridges and spatial variations in the degree of bedform modification record dynamic changes in regional subglacial environments during the last deglacial cycle. This ice-mass variability cannot be reconciled with current Irish glacial models, which are based on immobile ice centres and ordered stages of ice retreat. In a wider context, these changes in bedform patterns and basal ice regimes have a similar signature to millennial-scale ice-mass oscillations recorded by dated proxy evidence elsewhere in the amphi-North Atlantic.

    U2 - 10.1002/(SICI)1099-1417(199711/12)12:6<519::AID-JQS313>3.0.CO;2-Q

    DO - 10.1002/(SICI)1099-1417(199711/12)12:6<519::AID-JQS313>3.0.CO;2-Q

    M3 - Article

    VL - 12

    SP - 519

    EP - 524

    JO - Journal of Quaternary Science

    T2 - Journal of Quaternary Science

    JF - Journal of Quaternary Science

    SN - 0267-8179

    IS - 6

    ER -