| Title | Protolith lithostratigraphy of the Greater Himalayan Series in Langtang, Nepal: implications for the architecture of the northern Indian margin |
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| Author | Dyck, B; St-Onge, M; Searle, M P; Rayner, N ; Waters, D; Weller, O M |
| Source | Himalayan tectonics: a modern synthesis; by Treloar, P J (ed.); Searle, M P (ed.); Geological Society, Special Publication 483, 2018 p. 1-24, https://doi.org/10.1144/SP483.9  Open Access |
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| Year | 2018 |
| Alt Series | Earth Sciences Sector, Contribution Series 20160307 |
| Publisher | Geological Society of London |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Area | Langtang; Himalayas; Nepal |
| Lat/Long WENS | 72.0000 96.0000 36.5000 25.0000 |
| Subjects | stratigraphy; geochronology; structural geology; lithostratigraphy; bedrock geology; basement geology; lithology; metamorphic rocks; metasedimentary rocks; amphibolite facies; gneisses; augen gneisses;
sedimentary rocks; quartzites; pelites; psammites; semipelites; igneous rocks; intrusive rocks; leucogranites; structural features; faults, thrust; fault zones; sutures; plate margins; radiometric dating; uranium lead dating; geological history;
depositional history; tectonic history; deformation; metamorphism; crustal shortening; intrusions; structural controls; isograds; structural analyses; Greater Himalayan Series; Indian Craton; Trans-Himalayan Batholith; Kohistan-Ladakh Arc; Indus
Tsangpo Suture Zone; Tethyan Himalayan Series; Lesser Himalayan Series; Great Counter Thrust; South Tibetan Detachment System; Main Central Thrust zone; Main Boundary Thrust; Peshawar Basin; Kashmir Basin; Sutlej Basin; Phanerozoic; Cenozoic;
Paleozoic; Silurian; Ordovician; Cambrian; Precambrian; Proterozoic |
| Illustrations | geoscientific sketch maps; cross-sections; photographs; Concordia diagrams; spectra; tables; schematic cross-sections |
| Program | GEM2: Geo-mapping for Energy and Minerals Baffin Bedrock Mapping |
| Released | 2018 09 20 |
| Abstract | Reconstruction of the protolith lithostratigraphy of amphibolite-facies metasedimentary rocks of the Greater Himalayan Series (GHS) in Nepal documents a single, long-lived passive-margin succession that
was deposited along the northern margin of the Indian Craton. In the Langtang area, Paleoproterozoic gneisses are unconformably overlain by a succession of upper Neoproterozoic-Ordovician fluvio-deltaic quartzite, basinal pelite and psammitic beds
that grade upsection into micaceous semipelite and pelite. U-Pb zircon geochronology yields maximum depositional ages between c. 815 and 460 Ma for the GHS in Langtang. Regional variations in the composition and thickness of the GHS along the length
of the Himalaya are attributed to siliciclastic depocentres centred on Zanskar in northern India, Langtang and Everest in central to western Nepal, which contrast with coeval marine carbonate shelf deposition in the Annapurna region. The protolith
lithostratigraphy documented for Langtang provides a coherent framework for interpreting subsequent Cenozoic Himalayan deformation, specifically the homogeneously distributed layer-normal shortening (i.e. flattening) and layer-parallel stretching
(i.e. transport-parallel stretching) that characterizes the GHS. Within the context of a single protracted northern Indian marginal sedimentary succession, the distinction between the Lesser, Greater and Tethyan Himalaya is structural rather than
lithostratigraphic in origin. |
| Summary | (Plain Language Summary, not published)
Reconstruction of the stratigraphy of metasedimentary rocks of the Greater Himalayan Series in Nepal documents a single, long-lived passive margin
sequence deposited on the northern margin of the Indian craton. U-Pb zircon geochronology constrains the timing of deposition of the Greater Himalayan Series in Langtang between ca. 815 and 460 Ma. Regional variation in the first-order composition
and thickness of the Greater Himalayan Series along the length of the Himalaya is attributed to the occurrence of siliciclastic depocenters centered on Zanskar in northern India, and Langtang and Everest in central to western Nepal, which contrast
with coeval marine carbonate shelf strata in Annapurna. Within the context of a single protracted northern Indian marginal sedimentary sequence, the distinction between the Lesser, Greater and Tethyan Himalaya appears to be more structural than
stratigraphic in origin. |
| GEOSCAN ID | 299615 |
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