AGL proposes two-dimensional seismic exploration in sections of two large licence areas extending from Raymond Terrace and Lake Macquarie to Merriwa in the Upper Hunter.

The chosen sites are concentrated between Cessnock, Broke and Singleton and around Scone.

AGL said seismic exploration used sound waves to create a map of the structures beneath the earth's surface. Geologists and geophysicists interpret the data for possible gas reserves and develop a plan for exploration drilling.

AGL said it was"non-intrusive" and planned to start in autumn.

The two areas are petroleum exploration licence area four, which covers Merriwa, Scone and Muswellbrook, and the contentious petroleum exploration licence area 267, which covers the Pokolbin and Broke Fordwich vineyards.

The Hunter Valley Protection Alliance and Hunter Valley Wine Industry Association have campaigned to have the vineyards area removed from the licence, which the government is assessing for another six-year renewal.

Alliance spokesman Graeme Gibson said the seismic exploration appeared to enter Pokolbin State Forest, and the group wanted to know when the company would submit its environmental review.

AGL said it was still in the project's technical assessment phase.

The public information session will begin at midday and will be held at AGL offices in John Street, Singleton.