3D executive chairman Noel Newell said this morning that in-house geotechnical studies continue to support the likelihood of a discovery in Tasmanian waters.

3D (70% and operator), which shares T/49P with Beach Energy (30%), believes that a successful discovery could be developed through the existing Thylacine and Geographe gas facilities, rapidly bringing new gas into the east coast market, possibly in time to meet a projected shortfall if the development is fast-tracked.

Flanagan sits in just 100m of water, ideal territory for a jack-up rig, and the area has been largely overlooked for around 50 years because of the complexity of the Otway Basin subsurface geology.

The junior has covered almost 25% of the northern area of T/49P with 3D seismic and believes it has significantly derisked its lead drilling candidate with recent petroleum system and amplitude-versus-offset analysis.

It can see evidence for both reservoir and seal units analogous to the neighbouring Thylacine and Geographe fields, and there are both amplitude and Class III AVO responses consistent with the presence of gas, as predicted by the petrophysical study.

The seismic response corresponds well to the mapped structure.

If it can affect a farm-out the drilling would assess a prospect with a best estimate prospective resource of 1.38 trillion cubic feet and upside to 2.68Tcf.

Success would help open up the overlooked area of the Otway Basin, where 3D believes enough gas has been generated to fill all of the mapped prospects and leads within the last 25 million years, reducing the risks of breaching.

The junior is also excited by the remapping of the Seal Rocks lead in the block's underexplored southern region, which appears to be significantly larger than previously interpreted, with multiple Tcfs contained in a series of adjacent fault blocks, although the area lacks 3D seismic.

The North West Shelf big gas style target is well positioned to receive significant gas charge while associated amplitude anomalies are also observed on seismic, Newell said.

3D shares were up 6% this morning to $0.035.