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  • The North Westland deformation front runs offshore for 320 km between Cape Farewell and Hokitika at a distance of 3–30 km from the coast. From marine seismic reflection profiles integrated with published sediment core and coastal uplift data, we infer late Quaternary activity on six major reverse faults. The principal structures are the Cape Foulwind, Kahurangi and Kongahu faults and the newly named Farewell, Elizabeth and Razorback faults. They include Late Cretaceous and Paleogene rift faults that were reactivated as reverse faults during the late Cenozoic. Best estimates of late Quaternary (<120 ka) slip rates for different faults range from 0.05–0.75 mm a–1. Nine potential earthquake sources are identified, including four segments of the Cape Foulwind Fault. They are of length c. 20–120 km, are potentially capable of producing moderate- to large-magnitude earthquakes of Mw 6.7–7.8 and represent a seismic risk to coastal communities. Best estimates of recurrence intervals for individual fault sources range from about 7600 years to 30,400 years, with large uncertainties in slip rates of up to –0.4, +1.0 mm a–1 reflected by the wide range of recurrence intervals.
    Data Types:
    • Collection
  • The North Westland deformation front runs offshore for 320 km between Cape Farewell and Hokitika at a distance of 3–30 km from the coast. From marine seismic reflection profiles integrated with published sediment core and coastal uplift data, we infer late Quaternary activity on six major reverse faults. The principal structures are the Cape Foulwind, Kahurangi and Kongahu faults and the newly named Farewell, Elizabeth and Razorback faults. They include Late Cretaceous and Paleogene rift faults that were reactivated as reverse faults during the late Cenozoic. Best estimates of late Quaternary (<120 ka) slip rates for different faults range from 0.05–0.75 mm a–1. Nine potential earthquake sources are identified, including four segments of the Cape Foulwind Fault. They are of length c. 20–120 km, are potentially capable of producing moderate- to large-magnitude earthquakes of Mw 6.7–7.8 and represent a seismic risk to coastal communities. Best estimates of recurrence intervals for individual fault sources range from about 7600 years to 30,400 years, with large uncertainties in slip rates of up to –0.4, +1.0 mm a–1 reflected by the wide range of recurrence intervals.
    Data Types:
    • Collection
  • The North Westland deformation front runs offshore for 320 km between Cape Farewell and Hokitika at a distance of 3–30 km from the coast. From marine seismic reflection profiles integrated with published sediment core and coastal uplift data, we infer late Quaternary activity on six major reverse faults. The principal structures are the Cape Foulwind, Kahurangi and Kongahu faults and the newly named Farewell, Elizabeth and Razorback faults. They include Late Cretaceous and Paleogene rift faults that were reactivated as reverse faults during the late Cenozoic. Best estimates of late Quaternary (<120 ka) slip rates for different faults range from 0.05–0.75 mm a–1. Nine potential earthquake sources are identified, including four segments of the Cape Foulwind Fault. They are of length c. 20–120 km, are potentially capable of producing moderate- to large-magnitude earthquakes of Mw 6.7–7.8 and represent a seismic risk to coastal communities. Best estimates of recurrence intervals for individual fault sources range from about 7600 years to 30,400 years, with large uncertainties in slip rates of up to –0.4, +1.0 mm a–1 reflected by the wide range of recurrence intervals.
    Data Types:
    • Collection
  • The North Westland deformation front runs offshore for 320 km between Cape Farewell and Hokitika at a distance of 3–30 km from the coast. From marine seismic reflection profiles integrated with published sediment core and coastal uplift data, we infer late Quaternary activity on six major reverse faults. The principal structures are the Cape Foulwind, Kahurangi and Kongahu faults and the newly named Farewell, Elizabeth and Razorback faults. They include Late Cretaceous and Paleogene rift faults that were reactivated as reverse faults during the late Cenozoic. Best estimates of late Quaternary (<120 ka) slip rates for different faults range from 0.05–0.75 mm a–1. Nine potential earthquake sources are identified, including four segments of the Cape Foulwind Fault. They are of length c. 20–120 km, are potentially capable of producing moderate- to large-magnitude earthquakes of Mw 6.7–7.8 and represent a seismic risk to coastal communities. Best estimates of recurrence intervals for individual fault sources range from about 7600 years to 30,400 years, with large uncertainties in slip rates of up to –0.4, +1.0 mm a–1 reflected by the wide range of recurrence intervals.
    Data Types:
    • Collection
  • Center for Advanced Marine Core Research, Kochi University
    Data Types:
    • Collection
  • Abstract Low-latitude continental shelves, mixed siliciclastic–carbonate sedimentary systems, provide an understanding of sedimentary environments driven by paleoclimatological processes. The Bonaparte Gulf, northwestern Australian continental shelf, is among the widest in the world, ranging to 500 km, with shallow carbonate terraces and platforms that were exposed during periods of lower sea level. The dominant sediments type switches between carbonate and siliciclastic over a sea-level cycle. However, the mechanism of sedimentary environmental change in the Bonaparte Gulf is not clearly understood. Here, we present a record of sedimentary environmental change from ca. 24 to 35 ka that is related to sea-level variability and exposure of carbonate terraces and platforms. Multi-proxy data from a marine sediment core show a sea-level change induced switch in sedimentary environment from siliciclastic to carbonate-dominated sedimentation during the last glaciation. Radiocarbon ages constrain the timing of this switch to ca. 26 ka, associated with a local sea-level fall of −90 m.
    Data Types:
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  • Quaternary Palynology Laboratory, Birbal Sahni Institute of Palaeobotany
    Data Types:
    • Dataset
  • Pollen records from a 1.8-m deep sediment profile from Lakadandh Swamp, Baikunthpur Forest Range of Koriya District, Chhattisgarh (C'garh, central India), show the late Quaternary vegetation and climate history. Lakadandh Swamp occurs in the core monsoon zone of India. The study revealed that between ∼12,785 and ∼9035 cal. yrs BP, tree savannah vegetation, – composed of Poaceae, Amaranthaceae, Tubuliflorae along with the tree taxa Holoptelea sp. and Sapotaceae; sparsely distributed Acacia sp., Emblica officinalis, Lagerstroemia sp., Madhuca indica and Syzygium sp., thickets of Ricinus and Zizyphus sp. – occurred in the region under a cool and dry climate probably indicative of reduced monsoon precipitation. The early part of this phase is comparable with the Younger Dryas (YD) cold event which occurred between ∼12,800 and ∼11,500 yrs BP. Between ∼9035 and ∼4535 cal. yrs BP, the expansion of existing taxa Holoptelea sp., Sapotaceae, Madhuca indica, Ailanthus excelsa and Lagerstroemia sp. as well as the appearance of Acacia, and Shorea robusta, Acanthaceae, Rungia sp., and Ricinus sp., shows the tree savannah vegetation was replaced by open mixed tropical deciduous forest under a regime of warm and moderately humid climate with increased monsoon precipitation. Since ∼4535 cal. yrs BP to Present, owing to the improvement of most of the forest constituents, particularly Madhuca indica, Holoptelea sp., Sapotaceae and Lannea coromandelica, and also with immigration of Terminalia sp., Diospyros sp., Butea sp. and Maytenus sp., mixed tropical deciduous forest has taken over the space covered by open mixed tropical deciduous forest under a warm and relatively more humid climate, with further increase in monsoon precipitation. The existing cereal-based agricultural practice increased during the latter two phases, which could be attributed to increased monsoon precipitation.
    Data Types:
    • Dataset