报告人：Sergey Popov(副教授)

时间：2023.7.12 9:30-11:30

地点：测绘馆401会议室

报告人简介

  Dr. Sergey Popov is a leading geophysicist of the Antarctic Division of the Polar Marine Geosurvey Expedition, Russia, also associate professor of Saint Petersburg State University. For thirty years he studies Antarctica by radio-echo sounding and GPR, also subglacial lakes especially Lake Vostok.

报告简介

  The main results of glaciological and geophysical engineering surveys, conducted during three summer field seasons of 2013– 2016 (59–61st Russian Antarctic Expeditions – RAE) near the Russian Station Mirny (East Antarctica), are presented in this lecture. The objective of these works was to site and then organize a new airfield for the landing of medium-range aircraft with ski landing gears. Investigations included aerial photography, GPR surveys (georadar profiling), ice core drilling, and the installation of landmarks to measure the velocity of the glacier motion. The GSSI ground-penetrating radars with the main frequencies of 270 MHz and 900 MHz were used. In addition, special explorations were conducted for detecting the englacial crevasses by means of remote-sensing methods. The GPR data allowed a revealing of the boundary between snow-firn layer and atmospheric ice. In the course of processing of 252 travel-time curves of the diffracted waves, a kinematic model of the sub-surface part of the glacier has been constructed. It was found that the dielectric permittivity of the snow-firn layer averages 2.43; a similar value for the atmospheric ice amounts to 3.0. The GPR data made it possible to determine interglacial (englacial) crevasses and to choose the most favorable field for the landing. On February 10, 2016, the first middle-range aircraft DC 3T (BT 67) landed on the new runway near the station Mirny.