Scintillation specialist Applied Scintillation Technologies (AST) has seen sales for its glass scintillator detectors for neutron porosity logging applications rise by 300% over the past year
Neutron porosity logging of oil-bearing is a well-established technique in oil exploration.
The search for new oil reserves not only means the identification of new oil fields, but ensuring the fullest use of existing oil fields.
This has led to increased use of detection systems as the absolute extremities of current oil fields are mapped to ensure maximum extraction.
AST sales and marketing director Stuart Quinn said: "AST has extensive knowledge and experience in the field of neutron detection and this is reflected in the increased sales volume for these detectors.
"We are always happy to develop custom products for neutron detection and imaging in instrumentation and other applications".
The thermal neutron detector features cerium activated lithium enriched scintillator glass manufactured by AST in the form of thin-walled precision machined and polished cylinders.
The system features two of these cylinders, which detect the unique thermal neutron signature from oil-bearing rocks while discriminating against gamma rays which could interfere with the signal.
A fast neutron source is used to irradiate the rocks around the drill bit.
The thermalised neutrons resulting from the interaction with oil-bearing rocks are converted by the scintillator into light.
This is in turn detected by a photomultiplier tube to give a characteristic thermal neutron peak.
The low response of the glass to gamma allows the neutron peak to be detected without interference from these interactions.
This is particularly important in this application since the neutron source used has a high gamma signal.
The glass not only offers outstanding detection performance, but also offers the robustness towards vibration and extremes of temperature (up to 200C) necessary to operate in a sonde working up to 3km below the earth's surface.
These properties give this technology a significant competitive advantage over 3He tube detectors which have until now dominated the market.
The combination of the robustness and competitive pricing of these scintillation glasses may lead to more widespread usage and re-emergence in neutron porosity logging and related applications.
