Geovisualization of the Excavation Process in the Lesvos Petrified Forest, Greece Using Augmented Reality

Abstract

Augmented reality (AR), in conjunction with 3D geovisualization methods, can provide significant support in monitoring geoconservation activities in protected geosites, such as the excavation process in fossil sites. The excavation process requires a monitoring methodology that will provide a complete and accurate overview of the fossils, their dimensions, and location within the different pyroclastic horizons, and the progress of the excavation works. The main purpose of this paper is the development of a user-friendly augmented map application, specifically designed for tracking the position of petrified tree trunks, providing information for their geometric features, and mapping the spatiotemporal changes occurring in the surrounding space. It also aims to probe whether the rapid acquisition of a 4K video can generate cartographic derivatives of petrified findings during a geosite excavation. A database accumulated 2D and 3D cartographic information, while the geovisualization environment displayed the surface alterations, at two scales: a) 1:500 (excavation area) and b) 1:50 (trench level). Unmanned aerial systems (UASs), used for data acquisition in three excavation periods, consisted of two flights at two different altitudes: one to record changes throughout the study area and the other to provide information on trunks at trench level, via a high-resolution (4K) video. Image-based 3D modeling followed, in which image georeferencing was conducted with ground control points (GCPs). Finally, 2D and 3D geovisualizations were created to depict the excavation changes through time. The cartographic products generated at two cartographic scales depicted the spatiotemporal changes of the excavation.

Scale-Variant Flight Planning for the Creation of 3D Geovisualization and Augmented Reality Maps of Geosites: The Case of Voulgaris Gorge, Lesvos, Greece

“…The Voulgaris river gorge geosite requires high-resolution mapping to capture its natural beauty and integrity. [20,[57][58][59][60][61][62]. However, few studies exist in the literature that investigate how the quality of the 3D model of outdoor geological formations affects the data collection, considering the geographical and cartographic scale of the geosite and issues of optical variables on the 3D virtual space.…”

“…One of the factors contributing significantly to cartography science in recent years was the development of new geospatial data-collection tools [13][14][15]. One of these tools was the unmanned aerial system (UAS), which transformed the collection process of high-resolution images in a time-efficient, highly repetitive, and safe way over hard-to-reach and dangerous areas [16][17][18][19][20][21][22]. Several recent publications have described methods and techniques for the 3D mapping of spatio-temporal phenomena using UAVs [20,[23][24][25][26][27][28][29][30][31].…”

“…One of these tools was the unmanned aerial system (UAS), which transformed the collection process of high-resolution images in a time-efficient, highly repetitive, and safe way over hard-to-reach and dangerous areas [16][17][18][19][20][21][22]. Several recent publications have described methods and techniques for the 3D mapping of spatio-temporal phenomena using UAVs [20,[23][24][25][26][27][28][29][30][31]. Currently, UAVs are a viable option for high-resolution, remote-sensing data collection, applicable in a wide range of scientific, agricultural, and environmental fields [18,29,[32][33][34][35][36][37][38].…”

“…In geosite promotion and management there are references to augmented and virtual reality applications where users can browse through virtual space and observe specific geological formations remotely [56]. Furthermore, in other cases, users can visit a geosite in situ and receive 3D or 2D information for the area through an application installed on their mobile phone [20,[57][58][59][60][61][62]. However, few studies exist in the literature that investigate how the quality of the 3D model of outdoor geological formations affects the data collection, considering the geographical and cartographic scale of the geosite and issues of optical variables on the 3D virtual space.…”

An Efficient, Platform-Independent Map Rendering Framework for Mobile Augmented Reality

“…In geographic information science (GIScience) and related domains, combining AR and GIS to form an augmented reality geospatial information system (AR-GIS) can provide unique opportunities to enhance spatial experiences. This helps to advance applications in planning, analysis, urban development, and other geosciences in a transparent and intuitive way [4,5]. Several studies have shown the high value of AR in earth science.…”