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    Non-existent seamount in Google Earth
    From: Frank Reed
    Date: 2013 Dec 26, 15:39 -0800

    I think I've found a phantom atoll or seamount in Google Earth. It's pretty big, too: at least ten miles by five miles. It's suspiciously rectangular, AND its sides are nearly aligned with latitude and longitude lines.

    In Google Earth this phantom seamount is shown rising from the deep Pacific nearly to the surface near 0° 50' N, 174° 41' W. That's less than 200 miles southeast of Howland Island. You'll notice also that it has no detailed mapping associated with it. It appears to be a shallow zone with auto-generated seamount slopes fitting it to the nearby ocean floor model. I would bet a dollar that it simply doesn't exist! There are lots of small bumps and mountains in ocean floor maps that are spurious and result from converting gravity data into implied bathymetry, but this is different. I suspect some data source has this nearly rectangular region erroneously tagged at a very shallow depth when in fact it is very deep, and the algorthms that Google uses to generate the maps simply assimilated this erroneous data.

    I spotted this by comapring my deflection of the vertical map against Google Earth's bathymetric map. These usually line up pretty well. Compare in the attached image: each island or small group of islands has a corresponding "halo" around it in the map of the deflection of the vertical. But notice my "Mysterious Island". There is no matching halo --not even a hint of one. Some islands do not have any gravitational anomaly around them, but that's unlikely here. I think it's just bad data in Google Earth similar to the faux "Sandy Island" that made news last Spring.

    -FER


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