Granitic coastal geomorphology: applying integrated terrestrial and bathymetric LiDAR with multibeam sonar to examine coastal landscape evolution

Citations Over TimeTop 10% of 2014 papers

Abstract

ABSTRACT Coasts composed of resistant lithologies such as granite are generally highly resistant to erosion. They tend to evolve over multiple sea level cycles with highstands acting to remove subaerially weathered material. This often results in a landscape dominated by plunging cliffs with shore platforms rarely occurring. The long‐term evolution of these landforms means that throughout the Quaternary these coasts have been variably exposed to different sea level elevations which means erosion may have been concentrated at different elevations from today. Investigations of the submarine landscape of granitic coasts have however been hindered by an inability to accurately image the nearshore morphology. Only with the advent of multibeam sonar and aerial laser surveying can topographic data now be seamlessly collected from above and below sea level. This study tests the utility of these techniques and finds that very accurate measurements can be made of the nearshore thereby allowing researchers to study the submarine profile with the same accuracy as the subaerial profile. From a combination of terrestrial and marine LiDAR data with multibeam sonar data, it is found that the morphology of granite domes is virtually unaffected by erosion at sea level. It appears that evolution of these landscapes on the coast is a very slow process with modern sea level acting only to remove subaerially weathered debris. The size and orientation of the joints determines the erosional potential of the granite. Where joints are densely spaced (<2 m apart) or the bedrock is highly weathered can semi‐horizontal surfaces form. Copyright © 2014 John Wiley & Sons, Ltd.

Related Papers

• Simulation Research on Submarine Evasion to Fight against Dipped Sonar Searching(2009)
• → How useful is bathymetric information in the classification of high frequency sonar surveys?(2004)
• A Study on the Modeling and Simulation of On-called Anti-submarine of ASW Helicopter by Using Dipping Sonar(2013)
• Function Simulation of Submarine Sonar(2004)
• → PRELIMINARY GEOMORPHIC ASSESSMENT OF SUBMARINE AND SUBAERIAL-TO-SUBMARINE LANDSLIDES IN BARRY ARM FJORD, ALASKA(2022)