Mapping site-level microtopography with Real- Time Kinematic Global Navigation Satellite Systems (RTK GNSS) and Unmanned Aerial Vehicle Photogrammetry (UAVP)

Abstract

Microtopographic mapping has a long history in archaeology and has gained prominence recently owing to the proliferation of digital technologies. With such proliferation, it becomes necessary to compare and contrast different approaches based on a common set of criteria. This article compares the implementation and efficiency of two methods of mapping microtopography – ground-based Real-Time Kinematic Global Navigation Satellite System (RTK GNSS) and Unmanned Aerial Vehicle Photogrammetry (UAVP) survey – assessing the pros and cons of each, including those related to data quality. ‘Off-the-shelf’ solutions for methods were used to create the comparative dataset of microtopographic maps of six Middle and Late Bronze Age sites over the course of four seasons between 2007 and 2013 in the study area of the Central Lydia Archaeological Survey in western Turkey. Comparison of results demonstrate that the methods are similar with respect to ease of implementation, cost efficiency, and the (in)significance of data defects, while, unsurprisingly, UAVP survey can be greater than one order of magnitude more labor efficient than RTK GNSS survey and over two orders of magnitude more detailed as measured by data density. The accuracy of both methods is high, within typical error budgets for site-level mapping, and comparable to other recent digital mapping approaches. Accordingly, the results suggest that, given site suitability, UAVP is the more labor and cost-efficient method in the long run, with significant data quality benefits.

Keywords

• Agisoft Photoscan Pro
• RTK GNSS
• Mapping Microtopography
• Photogrammetry
• Unmanned Aerial Vehicle (UAV)
• Turkey
• Anatolia
• Kaymakçı
• Marmara Lake basin
• Gediz Valley