STRATIGRAPHY OF THE LATE QUATERNARY RAISED BEACH DEPOSITS IN THE NORTHERN PART OF LANGHOVDE, LUTZOW-HOLM BAY, EAST ANTARCTICA

• Main Authors: マエモク ヒデアキ, ミウラ ヒデキ, サイグサ シゲル, モリワキ キイチ, Hideaki MAEMOKU, Hideki MIURA, Shigeru SAIGUSA, Kiichi MORIWAKI
• Format: Report
• Language: English
• Published: Department of Geography. Yamaguchi University 1997
• Subjects: late Quaternary; raised beach; radiocarbon age; East Antarctic Ice Sheet; sea-level; Antarctic; East Antarctica; Langhovde; Raised Beach; Antarc*; Antarctica; Ice Sheet
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=2853; http://id.nii.ac.jp/1291/00002853/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=2853&item_no=1&attribute_id=18&file_no=1

Two trenches into a raised beach at the northern part of Langhovde revealed that the beach deposits are clearly divided into two marine sediment layers by an unconformity. Both sediment layers are mainly composed of sand and include in situ fossil shells of Laternula elliptica. Radiocarbon ages of the fossil shells collected from the upper layer ranged from 5270±60 yBP to 4050±80 yBP without a reservoir correction, and those from the lower layer ranged from 46420±1500 yBP to 32430±270 yBP. The Holocene upper layer is interbedded with deltaic sediments including reworked shell fragments. The unconformity is overlaid with a gravel layer that includes no marine fossils. The gravel layer was deposited under a terrestrial environment during a period of low-stand sea-level. These facts suggest the following : 1) The East Antarctic Ice Sheet retreated from the northern part of Langhovde and a transgression occurred prior to the Last Glacial Maximum (LGM); 2) The Ice Sheet had not re-advanced over the beach of the northern Langhovde even during the LGM; 3) Holocene transgression occurred around 5k yBP, and 4) Minor regression and transgression occurred during the Holocene transgression.