Theoretical Developments in Electromagnetic Induction Geophysics with Selected Applications in the Near Surface

Near-surface applied electromagnetic geophysics is experiencing an explosive period of growth with many innovative techniques and applications presently emergent and others certain to be forthcoming. An attempt is made here to bring together and describe some of the most notable advances. This is a difficult task since papers describing electromagnetic induction methods are widely dispersed throughout the scientific literature. The traditional topics discussed herein include modeling, inversion, heterogeneity, anisotropy, target recognition, logging, and airborne electromagnetics (EM). Several new or emerging techniques are introduced including landmine detection, biogeophysics, interferometry, shallow-water electromagnetics, radiomagnetotellurics, and airborne unexploded ordnance (UXO) discrimination. Representative case histories that illustrate the range of exciting new geoscience that has been enabled by the developing techniques are presented from important application areas such as hydrogeology, contamination, UXO and landmines, soils and agriculture, archeology, and hazards and climat

Remote Sensing of World War II Era Unexploded Bombs Using Object-Based Image Analysis and Multi-Temporal Datasets: A Case Study of the Fort Myers Bombing and Gunnery Range

During World War II, United States Army and Navy pilots trained on several hundred bombing ranges encompassing more than 12 million acres of land, leaving behind crater-scarred landscapes across the country. Post-war estimates suggest that 10-15% of aerial bombs used failed to detonate as intended, so these areas today are contaminated by a large number of dangerous unexploded bombs (UXB) which remain under the surface. Until recently, detecting UXB has been a tedious and expensive process done in three stages: (1) identifying and mapping general areas of concentrated bomb craters using historical air photos and records; (2) intensely searching these areas at a larger scale for much smaller UXB entry holes; and (3) confirming the presence of individual UXB using magnetometry or ground-penetrating radar. This research aims to streamline the workflow for stage 1 and 2 using semi-automated object-based image analysis (OBIA) methods with multi-source high spatial-resolution imagery. Using the Fort Myers Bombing and Gunnery Range in Florida as a study area, this thesis determines what OBIA software and Imagery is best at locating UXB in this environment. I assess the use of LiDAR-derived DEMs, historical air photos and high-resolution color digital orthophotos in Feature Analyst and Imagine Objective, and discuss optimal inputs and configurations for UXB searches in karst wetlands. This methodology might be applied by the detection and clearance industry in former war zones, and aid in restoring former training ranges to safe land uses in the U.S

The Journal of ERW and Mine Action Issue 17.1 (2013)

Clearance Operations | Gender and Age Issues | Notes from the Field | Research and Developmen

Mine Action 2020: Book of Papers

Book of papers that was to be presented at the 2020 Mine Action Symposium in Croatia. The Symposium canceled due to COVID-19

The Journal of ERW and Mine Action Issue 10.1 (2006)

Feature: Explosive Remnants of War | Focus: Africa | Profiles | Making it Personal | Notes from the Field | Research and Developmen

Developing a Hyperspectral Non-Technical Survey for Minefields via UAV and Helicopter

The main topic discussed in this paper is the research, development, and implementation of hyperspectral remote sensing technology in humanitarian mine action (HMA), mainly for non-technical survey (NTS) from aerial platforms. NTS should be conducted to determine whether landmines or unexploded ordnance (UXO) exist in considered areas and whether clearance is needed and if so, in what scope. The availability of the hyperspectral sensors (2011–2012) that are suitable for use with multi-engine unmanned aerial vehicles (UAV) enabled the development of systems for HMA. While large and costly airborne hyperspectral systems have been available for over two decades, they had little to no impact on HMA. Optical spectroscopy brought out interest in the relationship between vegetation and explosives, and this relationship is considered herein. Therefore, we briefly analyzed the state of landmine detection via hyperspectral technology, particularly the efforts to detect the mines due to the influence of explosives on vegetation reflectance spectra

A Field Evaluation of Airborne Techniques for Detection of Unexploded Ordnance

US Defense Department estimates indicate that as many as 11 million acres of government land in the U. S. may contain unexploded ordnance (UXO), with the cost of identifying and disposing of this material estimated at nearly $500 billion. The size and character of the ordnance, types of interference, vegetation, geology, and topography vary from site to site. Because of size or composition, some ordnance is difficult to detect with any geophysical method, even under favorable soil and cultural interference conditions. For some sites, airborne methods may provide the most time and cost effective means for detection of UXO. Airborne methods offer lower risk to field crews from proximity to unstable ordnance, and less disturbance of sites that maybe environmentally sensitive. Data were acquired over a test site at Edwards AFB, CA using airborne magnetic, electromagnetic, multispectral and thermal sensors. Survey areas included sites where trenches might occur, and a test site in which we placed deactivated ordnance, ranging in size from small ''bomblets'' to large bombs. Magnetic data were then acquired with the Aerodat HM-3 system, which consists of three cesium magnetometers within booms extending to the front and sides of the helicopter, and mounted such that the helicopter can be flown within 3m of the surface. Electromagnetic data were acquired with an Aerodat 5 frequency coplanar induction system deployed as a sling load from a helicopter, with a sensor altitude of 15m. Surface data, acquired at selected sites, provide a comparison with airborne data. Multispectral and thermal data were acquired with a Daedelus AADS 1268 system. Preliminary analysis of the test data demonstrate the value of airborne systems for UXO detection and provide insight into improvements that might make the systems even more effective