TIGHAR
Amelia Earhart Search Forum => The Islands: Expeditions, Facts, Castaway, Finds and Environs => Topic started by: Heath Smith on June 03, 2012, 02:47:09 PM
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I was comparing a couple of overlay images in Google Earth, the NZ survey aerial photo taken in 1940 and a recent satellite image, and the two images do not match up.
Is it possible that somehow the wreck moved about 330ft to the North?
My guess is that there must be some issue with the positioning of the overlays but I wanted to see if the wreck could have possibly moved since 1940.
Thanks.
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Is it possible that somehow the wreck moved about 330ft to the North?
I haven't been to Niku.
I will almost certainly never go to Niku.
I'm morally certain that the NC carved a pretty deep trench for itself when it climbed aboard the reef.
You couldn't lift it out of there and move it 330 ft. without massive equipment (what kind of rig would it take to lift 5000 tons?) and without leaving behind the scar from the original wreck.
My wildly amateur guess is that you should treat the NC as a fixed point and suppose that the other features are what have changed over the years.
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Could a major storm have moved the wreck?
Something is amiss. To make the 1938 image fit in to the satellite image location you have to rotate and move the image. Something is not right.
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For sure, the NC hasn't moved from its original position.
I think that Marty is right on, you need to match up the NC and anything else that doesn't match is the stuff that has moved.
keep in mind that the GE imagery is from space, while the NZ survey is from an oblique angle from an aircraft, so there are probably differences in the way things look, but the NC would be impossible to move, even by major storm.
Andrew
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Here is another couple of photographs to consider.
It is hard to imagine the shoreline moving by such a significant amount.
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I am not a photo analysis and interpretation expert, although TIGHAR does has the services of a very, very capable one available - for a fee, and I am sure he would be happy to assist if you fee that answering this question would in some way advance the cause. While I'm not saying it's impossible that the ship has moved since it hit the reef while going at full speed and running more than half its length up onto dry land, I'd give the odds at somewhere between 0 and 1 on a scale of 1 to 5.
LTM, who knows an expert is one who knows when it's time to call in the experts,
Monty Fowler, TIGHAR No. 2189 CER
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I tend to agree with Monty. I will say, however, that with the storms and tidal action over the past 75 years, it is 'possible' that the shore line has changes some from erosion. Doubt the reef has.
Tom
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Another photo.
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Now, as having been on a dive once or twice and been through a storm or two I would like to offer my non-expert thaughts here. I would be more apt to believe the NC moved than the land did. I have seen tankers thrown inland 3 city blocks, I have scene sunken wrecks moved 300 some odd yards. While I agree with you that it is not likely the NC moved I do think it is very possible that it has moved.
To be sure though you will need an expert as the angles are all different on those images. You have a good point and you may be right. But I do have to ask how does this help?
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Heath, if I could sugggest? You are trying to "match up" inherently dynamic elements that are separated by 60-odd years. It's not surprising to me at all that shorelines have changed, or that reeflines have changed. And at the end of the day, as Rich asks, ummmmm, To what end?
LTM,
Monty Fowler, TIGHAR No. 2189 CER
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Monty,
I originally was attempting to accurately locate the NC on the reef to take a few measurements when I noticed the discrepancy between the current wreck location and the photographs.
The question remains, did the shoreline move by 300ft or so, or did the shoreline?
Perhaps the shorelines did move, that is something that I think is worth looking at.
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Chris,
It is hard to say what kind of event could move such a ship.
It is possible as Andrew stated that it could not move and the island shoreline has changed significantly over time.
I am still trying to find a good landmark to use to sort it out.
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Rich does bring up a good point. I live very near Hunting Island, SC, and can attest that during my stay her---since 1965--that erosion has deffinately changes its shoreline, beach, and overal acreage of the island. Landmarks of just 20 years ago are noe very near bech front. Jeff--i would think the same of Tybee Island.
Now----i normally would say that a storm moving a grounded ship like the NC would not be possible, but having seen the effects of Hurricane Hugo in Charleston firsthand, I can attest that the power of wind and water is something to behold. (Never would have believed I would see a LARGE barge with a VERY LARGE crane, high and dry on Lockwood Blvd-waterfront--but I did.
So is it possible that Niku endured a storm of sufficent magnitude--or even a tsunami- that could have altered the NC's location. Yes it is.
Tom
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Thats correct Chris. Might be an interesting undertaking to find out how many storms, and the intensity since 1937. I do know of several earthquakes near Samoa, that may have triggered some activity.
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Irrespective of the camera angle used on the photo that was an overlay in Google Earth, the below photo shows that the ship was clearly South of the shoreline in this 1942 image.
As stated before, either the ship moved or the shoreline moved some 300ft+.
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For what it's worth, the shoreline moving gets my vote.
And at the end of the day, well, it's only a picture. That and $5 will get you a cup of coffee in DC.
LTM,
Monty Fowler, TIGHAR No. 2189CER
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Before getting too excited I would want to have the photos orthocorrected. There is so much skew introduced in them that you cannot take a good measurement. This is especially true when dealing with dynamic elements like reef based features.
You would need to get some pics from as top down as you could get and then find non dynamic fiducial points to work from to flatten the image. When working with highly variable edges like shorelines the tide level, surf edges and wave action, erosion fronts, vegetation encroachment or withdrawal, and a host of other factors means if you were actively trying to get images to work with you would have to go inland or more likely have to place artificial fiducial points.
Given that the wreck was so far onto the reef and no longer buoyant - I would suspect that it was pretty solidly fixed.
On the other hand if you take the ship as a fixed point and plot changing shoreline against it you might get some ideas on potential debris trains or burial dynamics.
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An interesting point to consider when it comes to analyzing the Bevington photo and the "Bevington Object" (aka Nessie), if only the position of the ship is static, and the shoreline is moving by perhaps as much as 300ft, shouldn't the ship be used as the single reference point assuming that it is the only object in the photo that didn't move?
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It would make for an interesting study for sure. There may be some photogrametric things that can be tried using the knowns on the ship size etc to get implied shoreline dynamics. Things like sand deposition and erosion. It isn't just the water levels that could be exposing and hiding artifacts. Cover a piece of landing gear with 2 feet of sand and to the visual search it may as well be invisible even when walking right over it. Two years later somebody glides over that same spot in their canoe and asks "Where the heck did THAT come from??!!"
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Shorelines are known to change a LOT, whereas reef edges change slowly. Looking at the various aerial photos of Niku over the years, the tree line can be seen to change distance from the "beach". Also, there is an easily observable change in vegitation at some distance from the beach, likely due to storms washing away the intermediate foliage, which also changes the observed shoreline.
I think the shoreline is a poor choice for reference. The Norwich City location is a better reference, but may have changed heading. The reef edge will also have changed, but slowly, as I understand. We need an expert on the subject.
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Take a look at This post (http://tighar.org/smf/index.php/topic,391.msg4460.html#msg4460) to see a dramatic shift in the Southern coastline.