However, there is still no trace of Mr Morgan's body, despite the positive identification of his helicopter using underwater sonar and camera equipment.
Wanaka Search and Rescue (SAR) co-ordinator Sergeant Aaron Nicholson said specialist Naval dive squads have now searched to depths of about 30m around the edge of the lake near the crash site.
Six further possible underwater targets have been identified by sonar equipment and these remain under investigation in the bid to locate signs of Mr Saxton, he said.
A southerly storm which passed over the region on Tuesday night brought high winds, snow down to almost lake level, and bitter cold.
The 31-year-old search and rescue pilot and his helicopter disappeared on Saturday afternoon, during a flight across Lake Wanaka from Haast.
Salvage and search attempts are focused on a location, north of Mou Waho Island and about 200m from the eastern shore of Lake Wanaka, where Stony Creek enters the lake from near the foot of Mount Burke.
Aerial searchers located an oil slick on the lake on Sunday, where bubbles of oil rose from underwater.
A heavy commercial barge is anchored over the site, where the heli- copter wreckage has been identified.
Uncertainty remains about whether the underwater wreckage and Mr Saxton's body, if found, will be recovered from the lake depths.
Navy diving team commander Andrew McMillan said the underwater terrain of Lake Wanaka had been "incredibly difficult" to search.
The underwater crash location is in one of the deepest parts of the lake, with sheer underwater cliffs dropping to depths of up to 300m.
A decision on whether the helicopter will be salvaged from the lake will be made by the Civil Aviation Authority as part of its crash investigation.
Any such recovery mission would take considerable time and effort, and would be a costly exercise carried out by commercial divers, Lt-cmdr McMillan said.
At the time of his crash, Mr Saxton and his father David were both on bail pending an appeal after being jailed for more than two years in February for the theft of Ngai Tahu greenstone from South Westland.
Both men are respected pilots, credited with many rescue missions, and the decision to convict them enraged many of their staunch supporters on the West Coast.
