Tag Archives: Splooge

Fieldwork Picture of the Day 9

Danny at the helm,  aaaargh Billy.

Danny at the helm, aaaargh Billy.

Underwater research at Section Cove, near Gaadu Din. I posted a picture earlier of a diver on the bottom.  Here is a view from topside — Danny, boat skipper, wise-ass and all round rock solid good guy — has a GPS-linked laptop in front of him which is displaying the bathymetry of Section Cove.  (see the image on Danny’s screen here, courtesy of Daryl).  This enables him to tow the sonar fish exactly where required, or, on this occasion, help position a small dredging bucket for bottom sampling purposes.  With differential GPS, you can position the ship to within less than a metre of where you want it, relative to the bottom.  This means measuring the distance between the GPS antenna and the crane and building in an offset, which is trickier than it sounds. The bathymetry is also sub-metre in resolution.  Thus, we can target the bucket exactly where we want it — of course strong currents and bucket flutter can still move it around some.  It has been slow progress on this work but all the pieces are in place for what could be an exciting breakthrough –  a base camp on a small lake, now drowned, dating to sometime older than 11,500 solar years ago would be most welcome considering most of our other sites of this age are rather one-dimensional.

The purpose of the camp could be base camp for bear hunting in the nearby Gaadu Din caves, or more likely sockeye fishing in the lake-stream system that used to flow along the terrain here, under Danny’s  keel.

The lake, the salmon, the cave, the creek.  Green tones are now underwater.

The lake, the salmon, the cave, the creek. Green tones are now underwater. Image prepared by Daryl.

Fieldwork Picture of the Day 8

black bog abbey road

John, Walrus, George and the Sandhill Crane

In which we do our best impression of the Beatles Abbey Road cover on Porcher Island (map).  Lining up like this was necessary because the surface of this bog was so mucky we had to dismantle an old grow-op to make a trail across the surface (yes, we then dismantled our trail).  This bog is a few metres  above sea level, but quite quickly down in the core sample there was a clear break to marine sediments, showing sea level had once been higher than today and then dropped to or past modern.  Carbon dating a piece of sediment from the interface showed sea level had fallen past this point by  10,000 years ago.

Terrestrial (left) overlay marine (right) sediments.

Terrestrial (left) overlay marine (right) sediments.

The picture to the right shows the core sample, with the clear distinction made between the brown, terrestrial, pond deposits to the left (upper) side of the core) while in the right (lower, older) part of the core you can see the sediments turn to a greenish marine clay, which contained small shell fragments and salt-water diatoms.  Taking a number of these core samples from different elevations (and therefore of preumptively different dates of sea level change) allows us to stitch together a curve or graph of sea-level history.  Using this curve, we can then identify ancient coastlines (both underwater and above high tide) with greater certainty and accuracy, allowing for more efficient and productive archaeological survey on these ancient landforms.  On the map linked above, you can see the long linear lakes and ponds paralleling the modern shoreline.  These lakes highlight the former  eastern shores of  Oval Bay at higher sea levels.

Fieldwork Picture of the Day

Duncan with his feet in a 12,000 year old bog

Duncan with his feet in a 12,000 year old bog

While doing the Anthro 449 site, I’m finding a lot of pictures I haven’t seen lately, so I might as well post some of them here.  This one shows Duncan digging at Kilgii Gwaay (map) in 2002.  This was an unusual project, working in the intertidal zone between tidal windows — so about 6 hours per day of frenzied activity (read: poor napping) until the unit flooded again.  In this instance, the unit was 4 foot by 4 foot to accomodate the dimensions of plywood shoring.  There wasn’t a lot down in this unit, at least not archaeologically, but we do have a huge sample of woody bits from the organic deposits at the bottom.  In essence, the unit was placed on the edge of an ancient pond that formed post-glacially and  then lived a quiet life in the anonymous southern forests of Haida Gwaii – only to be rudely interrupted around 9450 14C years ago by rising sea levels, which made it attractive for a brief window of human occupation.  So – from a small pond in the forest, to a busy camp site, to a beach, all in a span of about 50 years.  And now, with falling sea levels, back to a beach.  The archaeological site is eroding somewhat, but nonetheless there are patches of intact shell midden and as it shows here, a large amount of terrestrial freshwater-saturated pond splooges under this beach.