Like Sherlock Holmes, historians are on the prowl for interesting cases.   At times they cry out with enthusiasm, “The game’s afoot!” when they discover something that engages their attention so completely that it overrides their sense of public presence.  So it was when I came upon the following article from the Morning Record, dated June 15, 1899:

Strange Phenomenon

The annual explosion in the bay, opposite the G.R. & I depot occurred Monday. The water boiled furiously for several minutes and finally burst into the air with considerable force raising a large body of water about four feet above the surface.  These submarine disturbances have been a mystery for many years and as yet no explanation has been made to account for the disturbances.  The gushing of the water was observed by several persons yesterday.

Lucille Zoulek’s index to local newspapers indicated another article upon the same subject thirteen days later.  It gave even more details:

Boiling Again

There was another submarine explosion on the bay yesterday east of the G.R. & I depot.  The water was thrown into the air about 20 feet and the commotion was vigorous and continued several minutes.  Some persons in a boat chanced to be over the spot at the time and they had a lively time for a few minutes. This is the third eruption of the kind this season.

The G.R. & I depot was located near the water where the Boardman River empties into the Bay.  In the first account, the water boiled and burst four feet high, but in the second, it shot up some twenty feet high.  Indeed, boat passengers nearby would have a lively time of it. This was not a trivial rise of the water which occurs as a result of different air pressures on the Lake basin, but was something far more dramatic.

Questions arise like the bubbles of the furious bay: Was the account true?  Was it accurate?  Had such eruptions been observed in the past—or afterwards?  Did they occur at the same time of year?  And, finally, what causes them?  Most troubling to this historian is the bare fact that he is neither a geologist nor a student of the phenomena of the Great Lakes.   Still, there is the love of seeking out answers, a curiosity that grabs you by the neck and pushes you forward.  “The game is afoot!”

The first article indicated the phenomenon had been observed “for many years.”  The first thing to do would be to locate other articles that could give new locations, new times of year the eruptions occurred, and new descriptions that might shed light on its nature.  A fellow historian searched not the deepest recesses of the state archives, but the deepest recesses of the internet.  She turned up the following account recorded in the Jackson Citizen-Patriot, August, 1883:

In Grand Traverse bay recently, at some distance out in deep water, between Traverse City and Marion Island, the water began to boil and surge, and presently rose in vast jets to the height of from 10 to 20 feet.  Being observed from the shore no details could be given on account of the distance, but the same thing had taken place years before and some two years ago, according to an account given by the Herald at that time, parties in a boat were so nearly on the spot that they were obliged to hasten out of its way.  They describe the water as apparently boiling from the very bottom of the bay, which in that place was nearly or quite one hundred feet deep, bringing up with it vast quantities of mud and other substances and emitting an intensely unpleasant sulphurous smell.  The area of the eruption, if it may be so called, was about twenty feet in diameter and the time about half an hour.  At intervals the water would subside into calmness and then the commotion would begin again.  It is said by old settlers that the same thing has occurred in other years.  The disturbance is always in a line between Traverse City and the island.  It is well known by old residents that there are places in the bay where salt water springs bubble up through the water, in the neighborhood of the island.  It is possible there are submarine openings of other descriptions, either volcanic or otherwise.  It is know to scientific men that there is a tract of country on the eastern shore of Michigan, in the neighborhood of Thunder bay directly across the state from Grand Traverse bay, where slight earthquakes are frequent, and in fact the bay was named by the Indians from the rumbling noise that from time to time was heard in the interior of the earth.  It is possible that the tidal waves, as well as Traverse bay disturbances, may arise from volcanic action as a common cause, and all newspaper readers are well aware that there has never been a time within the memory of the present generation when the earth seemed to be in such a state of internal agitation as at the present, many of the known volcanoes of the world being in active eruption, now ones breaking out where none were known before, and earthquake shocks, both slight and severe, frequent in every part of the world.

This eruption was in August!  So they do not always occur in June.  The location was somewhat different: Marion Island (now known as Power island) is some distance from the city.  However, upsurges and boilings occur along a line that runs from Traverse City to the island.  Would that imply an underwater seam of rock exists there?  Could that suggest a cause?

This eruption occurred in a deep part of the Bay at a place “more than a hundred feet deep.”  Furthermore, it sent up mud to discolor that water and emitted a “sulphurous smell,” an observation that set the editor to wondering if volcanic activity might be responsible.  At a time before plate tectonics and fault lines were understood, that suggestion was reasonable: after all, weren’t volcanoes like Vesuvius erupting all over the Earth?  Krakatoa was making ominous rumblings, though it’s eruption would occur later in August.  In the light of our present knowledge about volcanoes and earthquakes we reject the likelihood of volcanic activity so close to home.  There must be another explanation for event.

Once again, my historian friend comes to the rescue: she sends me a link to Alexander Winchell’s, A Report on the Geological and Industrial Resources of the Counties of Antrim, Grand Traverse, Benzie and Leelanaw in the Lower Peninsula of Michigan, printed in 1866.  On page 59 a clue jumps from the page that helps me to understand the cause of the “strange phenomenon” upon the bay.

The well authenticated existence of an ancient salt spring on the neck of land connecting Harbor (Hog) island (now, Marion or Power island) with the peninsula, I should regard as a confirmation of this opinion [that the salt/gypsum layer found in SE Michigan should be found elsewhere in the lower Peninsula] since, if a fissure existed in the overlapping rocks, the brine would tend to rise by hydrostatic pressure, as an artesian boring.  Deacon Dame of Northport, one of the oldest residents of the region, has furnished me with detailed information which seems to fully authenticate the current tradition relative to the former existence of this spring.

Winchell is saying that a layer of salt water lies trapped between two layers of rock in a manner that reminds him of rock formations in southeastern Michigan.  The liquid is under pressure and, if rock layers are exposed, it will come out to make a saltwater spring.  I wonder: if a wider fissure in the overlying rocks occurred, wouldn’t the brine jet out to form a fountain twenty feet high?  Is the cause of boiling and surging due to the sudden release of pressure as an underwater seam of rock opens?

If only observers back then had tested the water for salt!  Asking them to taste it would have been more than anyone should ask.  I predict it would be salty, perhaps so salty nearby fish would have been killed.   At any rate, the salt springs found locally could be linked to the eruptions in the bay.

The mystery of surging bay water has been ignored for most of the twentieth century because it was not observed over that period of time: I have been unable to find further descriptions of it after 1899.   Why has the bay been so quiet over the past hundred years?  I do not know, but I would like to find out.  Are there geologists out there who would like to participate in this investigation?  Goodness knows—there are tons of questions to be answered.

Richard Fidler is co-editor of Grand Traverse Journal.