Remote sensing of eskers from Vormsi and Väinameri vicinity, northwestern Estonia

Abstract

We have utilised techniques of remote sensing in combination with ground observations in order to investigate eskers of the Vormsi and Väinameri region of northwestern Estonia. Landsat Thematic Mapper (TM) images were the basis for recognition and regional interpretation of esker systems, and kite aerial photography was employed for detailed, low-height views of selected eskers. A special Landsat TM composite was developed to enhance the display of shallow sea floor features. On this basis, we have extended known, land-based eskers across the sea floor, and we have identified additional probable eskers marked by shallow shoals and tiny islands. The known and suspected eskers of Vormsi and surroundings demonstrate a regular pattern in their distribution, which we suggest represents a subglacial drainage network that was anastomosing in character. The esker network is located along the central pathway of the Väinameri ice lobe, and the overall direction of drainage was toward the Palivere glacial limit. We interpret eskers of the Vormsi-Väinameri vicinity as evidence for substantial meltwater discharge beneath the Väinameri ice lobe, which terminated in a proglacial lake.