Al Naqfah Fort
Topographic Survey
Al Naqfah Fort is a historic fortification located in the city of Al Ain, near the southern border of Al Ain Oasis. The archaeological site is built upon the eastern side of Jebel Hafit and has deteriorated substantially over time. The components that remained, including earthen block foundations, remnants of pebble-and-clay clad walls, as well as pottery sherds dating back to the Late Islamic and Iron Ages, alluded to a fortification used to protect Al Ain Oasis.
Terrestrial photogrammetry.
3-D point cloud in ReCap.
Digital Elevation Model (DEM) of Naqfa Fort Context.
Topographic Contour Map and Profile of Al Naqfah Fort’s Cultural Landscape
The team members met to discuss the methodology for documentation containing different landscape components. This case study highlights the global and local applications of survey technologies in documenting the historic environment of Abu Dhabi.
It was agreed to carry out documentation exercises for two particular spatial levels: the rocky hillside section of
Wadi Al Sarooj (Level 1), and
Al Naqfah Fort (Level 2).
The area for the survey, which covered an area of approximately 20 square kilometres, was determined based on the desired deliverables for the case study.
Level of Detail: 2 and 3.
Measurement of 13 control points throughout the site was facilitated through a Leica total station.
This data was used to orient
the 3-D scan data.
3-D scanning was conducted with a FARO laser scanner to capture the geometry of Al Naqfah Fort and the surrounding landscape. A total of 28 scans were performed.
Aerial photography was conducted using an RPA (drone) to capture the site’s topographic data.
Photographs were taken with a high-quality digital camera to produce a photographic portfolio for the site, and for use in the
photogrammetric applications.
Terrestrial photography was used to capture the details of the Fort.
Creation of a metrically accurate 3-D point cloud using 3-D scan software FARO SCENE and AutoDesk Recap software. The scans were merged in the software using the control points measured with the total station.
Creation of a metrically accurate photogrammetric model of the Fort using terrestrial photography and photogrammetry software Agisoft Metashape. It illustrates the efficiency of aerial photogrammetry in producing high quality, metrically accurate 3-D models, even for very large areas and landscapes.
A highly detailed and metrically accurate 3-D model of Al Naqfah Fort was developed. The model was exported as a 3-D PDF file which could be measured and manipulated in Adobe Acrobat. A topographic landscape model was created using the aerial photographs, photogrammetry software and the control points from the total station and 3-D scanner. A digital elevation model (DEM) was created in ESRI ArcGIS software and used to develop the contour lines for the topographic contour map.
The contour lines were imported into AutoCAD to create topographic drawings. The drawings were generated following the standardised AutoCAD template.