TY - JOUR
T1 - Tectonostratigraphy of the Late Archean Dharwar Supergroup, Dharwar Craton, India
T2 - Defining a tectonic history from spatially linked but temporally distinct intracontinental and arc-related basins
AU - Krapež, Bryan
AU - Srinivasa Sarma, D.
AU - Ram Mohan, M.
AU - McNaughton, Neal J.
AU - Rasmussen, Birger
AU - Wilde, Simon A.
PY - 2020/2
Y1 - 2020/2
N2 - The Dharwar Supergroup comprises the unconformity bound Bababudan and Chitradurga groups. The Bababudan Group, which is best preserved in the Western Dharwar Craton, records a divergent margin comprising a basalt-dominant intracontinental rift sequence, a shale-BIF drift sequence, and a sandstone-shale thermal-subsidence sequence. The rift stage evolved from ∼2765 Ma to ∼2720 Ma, whereas the succession was folded, uplifted and eroded during development of a convergent continental margin from ∼2680 Ma. Ocean opening was to the east or southeast. The Chitradurga Group records a two-stage back-arc basin behind an east-facing continental arc. Stage I evolved between ∼2609 Ma and ∼2582 Ma, and Stage II between ∼2582 Ma and ∼2540 Ma. The two stages are separated by a subaerial unconformity. Stage I comprises siliciclastic fluvial, shallow-marine and deep-marine sedimentary rocks and bimodal volcanic rocks. Stage I is best preserved in the Western Dharwar Craton, but there are equivalents in the Eastern Dharwar Craton. Stage II in the Western Dharwar Craton comprises deep-marine turbidites of siliciclastic and volcaniclastic provenance, and basaltic and felsic volcanic rocks. Volcanic Stage II sequences in the Eastern Dharwar Craton define an arc-adjacent position. Tectonically driven cyclic uplift and erosion were responsible for the mismatch between preserved stratigraphic thickness and time, particularly for Stage II sequences. A remnant of a <2540 Ma late-stage basin in the northeast of the Eastern Dharwar Craton defines a syncollisional tectonic setting. The Dharwar Supergroup was deformed in a SW-verging hinterland magmatic fold/thrust belt from ∼2540 Ma.
AB - The Dharwar Supergroup comprises the unconformity bound Bababudan and Chitradurga groups. The Bababudan Group, which is best preserved in the Western Dharwar Craton, records a divergent margin comprising a basalt-dominant intracontinental rift sequence, a shale-BIF drift sequence, and a sandstone-shale thermal-subsidence sequence. The rift stage evolved from ∼2765 Ma to ∼2720 Ma, whereas the succession was folded, uplifted and eroded during development of a convergent continental margin from ∼2680 Ma. Ocean opening was to the east or southeast. The Chitradurga Group records a two-stage back-arc basin behind an east-facing continental arc. Stage I evolved between ∼2609 Ma and ∼2582 Ma, and Stage II between ∼2582 Ma and ∼2540 Ma. The two stages are separated by a subaerial unconformity. Stage I comprises siliciclastic fluvial, shallow-marine and deep-marine sedimentary rocks and bimodal volcanic rocks. Stage I is best preserved in the Western Dharwar Craton, but there are equivalents in the Eastern Dharwar Craton. Stage II in the Western Dharwar Craton comprises deep-marine turbidites of siliciclastic and volcaniclastic provenance, and basaltic and felsic volcanic rocks. Volcanic Stage II sequences in the Eastern Dharwar Craton define an arc-adjacent position. Tectonically driven cyclic uplift and erosion were responsible for the mismatch between preserved stratigraphic thickness and time, particularly for Stage II sequences. A remnant of a <2540 Ma late-stage basin in the northeast of the Eastern Dharwar Craton defines a syncollisional tectonic setting. The Dharwar Supergroup was deformed in a SW-verging hinterland magmatic fold/thrust belt from ∼2540 Ma.
KW - Archean
KW - Back-arc basins
KW - Dharwar Craton
KW - Rift basins
KW - SHRIMP geochronology
KW - Tectonostratigraphy
UR - http://www.scopus.com/inward/record.url?scp=85076515006&partnerID=8YFLogxK
U2 - 10.1016/j.earscirev.2019.102966
DO - 10.1016/j.earscirev.2019.102966
M3 - Article
AN - SCOPUS:85076515006
SN - 0012-8252
VL - 201
JO - Earth-Science Reviews
JF - Earth-Science Reviews
M1 - 102966
ER -