WorldView2 satellite imagery in remote sensing a past gold trading trail in Luzon: Testing ethnohistory-based and GIS-based models

This article examines the application of image enhancement techniques on high resolution and multi-spectral WorldView 2 satellite images in aid of remote sensing a past gold trading trail in Northwestern Luzon that was used from the PreSpanish Contact Period 10th to 16th c and the Spanish Contact Period (17th to 19th c). In delineating the corridor for the research, several ethnohistorical accounts were followed as interlocutors. The article posits that segments of the Aringay-Tonglo-Balatok gold trail are still visible on the landscape while other segments may have been converted to contemporary farm-to-market roads. Identification of the segments was made possible by application of image enhancement techniques on WorldView2 satellite imagery including resolution merge using Brovey transform, unsupervised classification using a fusion of built-up index and vegetation index. Satellite band combination for mining operations (yellow-NIR1-red edge), modified false color Infrared (NIR1-green-blue), and soils and constructions (red-blue-yellow) have also been of immense utility.