The use of geoscience methods for aquatic forensic searches

There have been few publications on the forensic search of water and fewer still on the
use of geoforensic techniques when exploring aqueous environments. Here we consider
what the nature of the aqueous environment is, what the forensic target(s) may be,
update the geoforensic search assets we may use in light of these, and provide a search
strategy that includes multiple exploration assets. Some of the good practice involved in
terrestrial searches has not been applied to water to-date, water being seen as
homogenous and without the complexity of solid ground: this is incorrect and a full
desktop study prior to searching, with prioritized areas, is recommended. Much
experimental work on the decay of human remains is focused on terrestrial surface
deposition or burial, with less known about the nature of this target in water, something
which is expanded upon here, in order to deploy the most appropriate geoforensic
method in water-based detection. We include case studies where detecting other
forensic targets have been searched for; from metal (guns, knives) to those of a nonmetallic
nature, such as submerged barrels/packages of explosives, drugs, contraband
and items that cause environmental pollution. A combination of the consideration of the
environment, the target(s), and both modern and traditional search devices, leads to a
preliminary aqueous search strategy for forensic targets. With further experimental
research and criminal/humanitarian casework, this strategy will continue to evolve and
improve our detection of forensic targets.