Amadeus Basin Permit EP 145 Update

2 June 2021

Mosman Oil and Gas Limited

("Mosman" or the "Company")

Mosman awards contract at Amadeus Basin Permit EP 145

Mosman Oil and Gas Limited (AIM: MSMN) the oil exploration, development and production company, has awarded the contract for an airborne gravity and gradiometry survey over EP 145, in the Amadeus Basin in the Northern Territory of Australia, to CGG Aviation (Australia) Pty. Ltd.

The acquisition of data is planned for mid-June and is a significant step in the exploration programme for EP 145 as it is the first time data will be acquired across the whole permit in order to identify where to focus the seismic programme to enable Mosman to identify a drilling prospect. The survey operation is subject to NT government approval, which was applied for in May.

The cA$300,000 gravity survey will provide valuable data regarding the subsurface geology across the entire 818 sq km permit area. Current subsurface seismic data is limited to the NW and central part of the permit and existing regional gravity data is too sparse to provide sufficient detail of the complex salt related structures which have been identified as hydrocarbon and helium leads within the permit.

The survey will be acquired using the high resolution Falcon Airborne Gravity Gradiometry System which has the ability to image salt and subsalt geometry across a range of depths. The technique measures the density contrast of the different rock layers with a higher level of resolution and sensitivity than standard gravity tools, improving confidence in the interpretation of high density and gravity features including salt related structures. The Falcon system has been used to successfully interpret drill targets across a variety of geological settings around the world including the Canning Basin Western Australia.

John W Barr, Chairman of Mosman commented: "This is a significant step in the exploration of EP 145. We are delighted to have awarded this contract in order for Mosman to be able to use the Falcon gravity and gradiometry data to assist with refinement of the 2D seismic programme in order to focus on potential drill targets in the permit."

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