scholarly journals A high-resolution record of early Miocene Antarctic glacial history from ODP Site 1165, Prydz Bay

2005 ◽  
Vol 20 (2) ◽  
pp. n/a-n/a ◽  
Author(s):  
Trevor Williams ◽  
David Handwerger
Keyword(s):  
High Resolution ◽  
Early Miocene ◽  
Prydz Bay ◽  
Glacial History

scholarly journals Combined high-resolution seismostratigraphic and morphobathymetric analysis reveals glacial history of the northwestern Chukchi margin, Arctic Ocean

2020 ◽  
Author(s):  
Sookwan Kim ◽  
Leonid Polyak ◽  
Young Jin Joe ◽  
Frank Niessen ◽  
Hyoung Jun Kim ◽  
...  
Keyword(s):  
High Resolution ◽  
Arctic Ocean ◽  
Glacial History ◽  
History Of

Imaging the Ice Sheet and Uppermost Crustal Structures with a Dense Linear Seismic Array in the Larsemann Hills, Prydz Bay, East Antarctica

2021 ◽  
Author(s):  
Lei Fu ◽  
Jingxue Guo ◽  
Junlun Li ◽  
Bao Deng ◽  
Guofeng Liu ◽  
...  
Keyword(s):  
High Resolution ◽  
Ice Sheet ◽  
Velocity Model ◽  
Dispersion Curves ◽  
Body Waves ◽  
East Antarctica ◽  
Prydz Bay ◽  
Larsemann Hills ◽  
Geophysical Surveys ◽  
Short Period

Abstract Comprehensive geophysical surveys including magnetotelluric, seismic, and aerial gravity–magnetic surveys are essential for understanding the history of Antarctic tectonics. The ice sheet and uppermost structure derived from those geophysical methods are relatively low resolution. Although ice-penetrating radar can provide high-resolution reflectivity images of the ice sheet, it cannot provide constraints on subice physical properties, which are important for geological understanding of the Antarctic continent. To obtain high-resolution images of the ice sheet and uppermost crustal structure beneath the Larsemann Hills, Prydz Bay, East Antarctica, we conduct an ambient noise seismic experiment with 100 short-period seismometers spaced at 0.2 km intervals. Continuous seismic waveforms are recorded for one month at a 2 ms sampling rate. Empirical Green’s functions are extracted by cross correlating the seismic waveform of one station with that of another station, and dispersion curves are extracted using a new phase-shift method. A high-resolution shear-velocity model is derived by inverting the dispersion curves. Furthermore, body waves are enhanced using a set of processing techniques commonly used in seismic exploration. The stacked body-wave image clearly shows a geological structure similar to that revealed by the shear-wave velocity model. This study, which is the first of its kind in Antarctica, possibly reveals a near-vertical intrusive rock covered by an ice sheet with a horizontal extent of 4 km. Our results help to improve the understanding of the subice environment and geological evolution in the Larsemann Hills, Prydz Bay, East Antarctica.

Forty million years of Antarctic glacial history yielded by Leg 119 of the Ocean Drilling Program

Polar Record ◽  
1989 ◽  
Vol 25 (153) ◽  
pp. 99-106 ◽  
Author(s):  
Michael J. Hambrey ◽  
Birger Larsen ◽  
Werner U. Ehrmann
Keyword(s):  
Large Scale ◽  
Middle Eocene ◽  
Prydz Bay ◽  
Glacial History ◽  
Ice Shelf ◽  
Ocean Drilling Program ◽  
Ocean Drilling ◽  
Early Oligocene ◽  
Amery Ice Shelf ◽  
Antarctic Continental Shelf

AbstractDuring Leg 119 of the Ocean Drilling Program, between December 1987 and February 1988, six holes were drilled in the Kerguelen Plateau, southern Indian Ocean, and five in Prydz Bay at the mouth of the Amery Ice Shelf, on the East Antarctic continental shelf. The Prydz Bay holes, reported here, form a transect from the inner shelf to the continental slope, recording a prograding sequence of possible Late Paleozoic to Eocene continental sediments of fluvial aspect, followed by several hundred metres of Early Oligocene (possibly Middle Eocene) to Quaternary glaciallydominated sediments. This extends the known onset of large-scale glaciation of Antarctica back to about 36–40 million years ago, the sedimentary record suggesting that a fully developed East Antarctic Ice Sheet reached the coast at Prydz Bay at this time, and was more extensive than the present sheet. Subsequent glacial history is complex, with the bulk of sedimentation in the outer shelf taking place close to the grounding line of an extended Amery Ice S helf. However, breaks in the record and intervals of no recovery may hide evidence of periods of glacial retreat.

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