A couple of Sitka residents who were fishing for halibut last month noticed an unusual feature on their depth sounder as they set gear a few miles north of town. Two-hundred feet below the surface of the water, the sounder slowly painted a picture of what appeared to be a volcano: A perfectly-formed cone about 100 feet tall, with a plum of gas trailing from the top.

Experts who’ve seen the image say it is no cause for alarm. It’s most likely a “mud volcano,” and it’s also not the only one near Sitka.

Locals don’t use rods and reels much to fish for halibut in Sitka. Rather, most set a subsistence skate – a long line baited with a dozen or more hooks that is laid right along the bottom from a slowly-moving boat.

Jacyn Schmidt was doing just this in November near the entrance to Nakwasina Sound, 5 miles north of Sitka. Schmidt was on deck, paying out the line.

“And then my friend who I was out fishing with was inside watching the depths on the sonar, and he noticed just a weird shape, and called me in to look at it with him,” said Schmidt.  

KCAW – “And what was it?”

“Well, I didn’t know what it was when I first saw it,” Schmidt continued, “but it certainly looked like some things I had seen before. I think we both immediately saw that cone shape and the kind of trail coming out of it, thinking that it could be an underwater volcano of a sort.”

Had it been anyone else, this might have been an invitation to head for the hills. But Schmidt is the regional geoscience specialist for the Tlingit and Haida Central Council. She’d been in Sitka for what has been a very interesting year – geologically – for the region. Her first impulse was to try and find the feature again, and then get on the phone.

“I’m aware of the geologic context of Sitka and the surrounding islands,” said Schmidt, “and spatially where the Queen Charlotte Fault is and where the Mt. Edgecumbe Volcanic Field is, and this location was just not adding up with the story that I know about our geology here. And so I just called the people who I knew had spent a lot of time thinking about the seafloor here.”

“It’s a classic example of what we have seen out on the (Queen Charlotte) Fault, down around Dixon entrance,” said Dr. Gary

Greene, one of the people Schmidt called.

Greene is a marine geologist, emeritus professor at the Moss Landing Marine Labs, and a leading expert on the undersea geology of the Queen Charlotte Fault.

“These types of plumes that come out of this volcanic-like cone are associated with what what we call mud volcanoes,” said Greene. “They’re not really active volcanoes, where magma comes flowing out, but it’s mainly fluids that come up from depth and carry with it sulfide-rich gasses and what have you.”

Greene has done sonar studies of the Queen Charlotte Fault that have produced images that are surprisingly similar to what Schmidt and her fishing partner saw on their depth sounder. The term “mud volcano” tends to conjure up thoughts of destruction, but – with a few exceptions – their only similarity to terrestrial volcanoes, like the nearby Mt. Edgecumbe, is their shape.

“If there’s a better term, I’d love to use it,” said Cheryl Cameron, “And right now, I don’t know about one.”

Cameron is a state geologist at the Alaska Volcano Observatory, and another expert Jacyn Schmidt consulted. Cameron is from Sitka, and is familiar with the depth sounders people use here while fishing. She hesitates to draw any conclusions from the image Schmidt captured, but admits that there are plenty of possibilities.

“A fishfinder is  looking for reflections within the water column,” she explained. “And so anything that has a density different from that of the rest of the water will cause a reflection. And so that reflector could be indicating a change in temperature or composition, it could be any kind of gas leaking out of the ground that would generate a plume with a different impedance, and thus a reflection. So it could be CO2 (carbon dioxide), it could be methane, it could be fluid with particulates in it –  there are a lot of possible causes that are not related to volcanism.”

Nakwasina, where Schmidt was fishing, is not within the Mt. Edgecumbe Volcanic Field – but it’s right next door. Edgecumbe generated headlines last spring when an earthquake swarm signaled that magma was stirring beneath the long-dormant crater. Subsequent radar studies showed that the flanks of the mountain had inflated by several inches over the last couple of years.  Although the mud volcano is probably not volcanic, Gary Greene says there’s not enough information to rule out that it might be related to what’s happening beneath Mt. Edgecumbe.

“It could very well be associated with that magma that’s moving up into the cone,” said Greene. “It could be that the heat from that magma has started a convection of warm or  hot waters that are now venting at that locality.”

The mud volcano is near a place called the Beehive. Everyone who’s been to Sitka on the ferry passes just a stone’s throw away. Jacyn Schmidt didn’t catch any halibut on the cone, but that unhappy fact hasn’t kept her away. Now, she’s fishing for information. 

“Well, we keep going back again,” she said. “My friend, whose boat I was on, has gone back to the same place to check again and again, and it’s still a bump under the water. I still have so many questions, and would like to go back with better instrumentation where you could really see but I’ll leave that to Gary and to Cheryl to direct.”

Although Schmidt is a professional scientist, accidentally discovering an underwater mud volcano is a form of citizen science that is very useful to researchers. Cheryl Cameron welcomes any and all observations of geologic phenomena at the Alaska Volcano Observatory. Gary Greene is going a step further, and looking for research funding to go down and take a look at the mud volcano, or at least take its temperature.

The Sitka Fire Department and Coast Guard Air Station Sitka were busy over the weekend, performing multiple rescues and medevacs throughout Southeast.

Around 6 p.m. on Friday evening (11/1/19), Search And Rescue responded to a call from two people in Nakwasina Sound who were caught in the dark in steep terrain.

Sitka firefighter Craig Warren said a search and rescue team responded to help get the pair back to their boat safely. Then, they escorted the pair back to the Starrigavan Boat Ramp. All-in-all, it took around nine hours, with the team returning to the fire station just before 3 a.m.

On Sunday (11/3/19), a Sitka-based Coast Guard crew medevaced a 76-year-old man with a head injury from Hoonah to Mt. Edgecumbe Medical Center in Sitka. 

The Coast Guard also reported Sunday it had medevaced a 24-year old man suffering from abdominal pain from Angoon to Sitka for medical treatment.

A local seafood processor is getting into the shellfish game. Silver Bay Seafoods applied for two mariculture leases earlier this year. The leases are good for ten years. If approved by the state, they will install 22 rafts in two separate locations northwest of Sitka for raising shellfish.

According to documents from the Alaska Department of Natural Resources, Silver Bay would lease 163 acres of state-owned tidelands in Nakwasina Sound, near Beehive Island, and 182 acres in Krestof Sound, south of Olga Point. There, they would cultivate both Pacific oysters and spat, which is oyster larvae, grow-out rafts of untreated wood supported by steel beams.

DNR now has until December 5th to review the lease application for Krestof Sound and until December 15th for Nakwasina Sound. Their decision also depends on the Alaska Department of Fish and Game, which must grant Silver Bay a permit for growing Pacific oysters and oyster spat. After that, DNR will announce their preliminary decision.  

Correction: An earlier version of this story stated that the period for public comment had closed. The state is actually taking public comment when their review process is complete. However, the period for the city of Sitka to comment closed in November.

A map shows the state land that the Department of Natural Resources is proposing to sell, near Dog Point north of Sitka. (KCAW photo/Rachel Waldholz)

The Department of Natural Resources is proposing a sale of state land at Nakwasina Sound, about eight miles north of Sitka.

The period for public comment on the proposal ends at 5pm, Thursday, March 20th.

The Assembly on Tuesday night (3-11-14) heard a brief presentation from DNR resource manager Tim Shilling describing the proposed sale, which includes 485 acres of land on the west side of Lisianski Peninsula, near Dog Point. The land is off Sitka’s road system, about three miles north of the Starrigavan ferry terminal by water.

Assembly member Ben Miyasato asked Shilling what kind of public response the plan had received.

“Has there been any opposition to the 485-acre [sale] and does it affect anyone in that area?” Miyasato asked.

“We did hold a public open house yesterday evening, and we had thirteen in attendance.  There was not any objection raised at that time, nor have we received any public comment, as of yet,” Shilling said.

The proposed land for sale wraps around 160 acres owned by Sitka’s Littlefield family. The family first staked it two generations ago, under the Alaska Native Allotment Act. For years they have run the Dog Point fish camp for kids on the property each summer.

Reached by phone, John Littlefield told KCAW that he has concerns about the plan, and will submit comment to the DNR this week. H said he wants to make sure that subsistence and historic sites on the peninsula are protected and that areas are set aside for public recreational use. Littlefield also noted that the proposal calls for dividing the land into no more than 50 parcels. He would like to see smaller parcels, he said, so that individuals can afford to purchase the land, rather than larger developers.

You can submit public comment by faxing your written comment to the Department of Natural Resources at 907-451-2751, or via email at landsales@alaska.gov.

You can find the public notice of the proposed sale here and the preliminary decision here.