A team of geophysicists will travel from Yorkshire to conduct surveys at Old Scatness and the Sands of Sound.
The University of Leeds specialists will be working in collaboration with Shetland Amenity Trust.
At Old Scatness they will attempt to establish if the archaeological site is bigger than previously thought, while the focus of their work in
Lerwick will be on a wall, possibly of Neolithic origin, that was unearthed due to coastal erosion earlier this year.
Survey work is due to begin on Thursday 30th June and will last about a week.
Old Scatness, was discovered in the 1970s during excavation work to extend the runway at Sumburgh Airport. The site contains settlements in the form of a broch and village, spanning at least 2000 years and ranging in age from Late Bronze Age to Iron Age.
Amenity trust geology project officer Jim Henderson said there was some indirect evidence that the known site may be larger although the exact extent and nature remained unknown. The Leeds survey would target the potential extension.
At the Sands of Sound much less is known about the recently discovered stonework and it is hoped that geophysics will help to delineate this settlement.
Mr Henderson said: “Geophysical surveys are a great way to discover more. Not only, are they a lot quicker to conduct than excavating, they are also non-invasive.
“In the particular case at Sands of Sound, any excavation could potentially destabilise the land and accelerate natural erosion.”
The survey techniques to be used in this project include magnetometry, ground penetrating radar and electromagnetics and will be carried out by two students, supervised by University of Leeds geophysics lecturer Adam Booth.
Mr Henderson said people were encouraged to visit the sites if they wished to find out more.
He added: “The Leeds team will be more than happy to explain their techniques and answer questions.
“For those planning to visit, it would be worth checking beforehand to find out which site the survey team are working at – details will be added to the Shetland Amenity Trust website when the work begins, and also added to the Facebook page.”