The northward motion of India since the Late Cretaceous

Author(s): Peirce, J. W.
Author Affiliation(s): Primary:
Woods Hole Oceanogr. Inst.-Mass. Inst. Technol., Woods Hole, Mass., United States
Volume Title: Geophysical Journal of the Royal Astronomical Society
Source: for the [Geophysical Journal of the Royal Astronomical Society, 52(2), p.277-311. Publisher: Blackwell] Royal Astronomical Society, London, United Kingdom. ISSN: 0016-8009 CODEN: GEOJAN
Note: In English. Woods Hole Oceanogr. Inst., Contrib. No. 3930. 65 refs.; illus. incl. tables, sketch maps
Summary: Paleomagnetic data are presented from the sediments and basalts at DSDP sites 213, 214, 215, 216, and 217 on or near the Ninetyeast Ridge in the eastern Indian Ocean. The paleolatitudes confirm that the ridge is attached to the Indian plate and that both have moved rapidly northwards since the Late Cretaceous. The Indian plate moved northwards with respect to the South Pole at an average rate of 14.9 cm/yr from 70 Myr ago until about 40 Myr ago when it slowed to its present rate of 5.2 cm/yr. Basement paleolatitudes on the Ninetyeast Ridge indicate that its volcanic source was approximately fixed in latitude near 50 S, supporting the concept that the ridge is the trace of the Kerguelen hotspot on the northward moving Indian plate. The existence of a mirror ridge on the Antarctic plate and the very shallow depths of basement formation on the ridge suggest that the Indian/Antarctic spreading center must have remained near the hotspot from 80 to 40 Myr in spite of one-limb spreading rates of up to 12 cm/yr. This is unexpected in view of the apparently small amount of motion of the Antarctic plate during this time. It is suggested that Antarctica was held nearly fixed by the geometry of other plate motions, and therefore the Kerguelen hotspot caused asymmetric accretion of new plate material at the southwestern end of the Ninetyeast Ridge. (Auth. mod.)
Year of Publication: 1978
Research Program: DSDP Deep Sea Drilling Project
Key Words: 18 Geophysics, Solid-Earth; Asia; Basalts; Cenozoic; Continental drift; Cretaceous; DSDP Site 213; DSDP Site 214; DSDP Site 215; DSDP Site 216; DSDP Site 217; Data; Deep Sea Drilling Project; Evolution; Genesis; Hot spots; Igneous rocks; India; Indian Ocean; Indian Peninsula; Latitude; Leg 22; Magnetic anomalies; Mesozoic; Mid-ocean ridges; Movement; Ninetyeast Ridge; Paleolatitude; Paleomagnetism; Plate tectonics; Pole positions; Rates; Stratigraphy; Tectonophysics; Upper Cretaceous; Volcanic rocks
Coordinates: S300000 N120000 E0950000 E0850000
Record ID: 1978021064
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from the Antarctic Bibliography, United States