This image was copied from wikipedia:en.

Eleven layers of the GISP2 w:en:ice core from a depth of 1855m.

Caption: "19 cm long section of GISP 2 ice core from 1855 m showing annual layer structure illuminated from below by a fiber optic source. Section contains 11 annual layers with summer layers (arrowed) sandwiched between darker winter layers."

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This image or file is a work of a U.S. Army Corps of Engineers soldier or employee, taken or made as part of that person's official duties. As a work of the U.S. federal government, the image is in the public domain. English | italiano | Nederlands | پښتو | русский | sicilianu | slovenščina | Türkçe | українська | +/−

http://www.ncdc.noaa.gov/paleo/slides/slideset/15/15_281_slide.html

The PNG crusade bot automatically converted this image to the more efficient w:en:PNG format. The image was previously uploaded as "GISP2 1855m ice core layers.gif".

03:20:24, 13 May 2005 (UTC) . . SEWilco (Talk | Contribs) . . 768x513 (183,345 bytes) (Eleven layers of the GISP2 w:en:ice core from a depth of 1855m. {{PD-USGov-DOC-NOAA}} http://www.ncdc.noaa.gov/paleo/slides/slideset/15/15_281_slide.html)

18:59:03, 21 April 2007 (UTC) Remember the dot (Talk | Contribs) ({{ShouldBePNG}})
03:30:54, 13 May 2005 (UTC) SEWilco (Talk | Contribs) (Add USACE notice)
03:20:24, 13 May 2005 (UTC) SEWilco (Talk | Contribs) (Eleven layers of the GISP2 w:en:ice core from a depth of 1855m. {{PD-USGov-DOC-NOAA}} http://www.ncdc.noaa.gov/paleo/slides/slideset/15/15_281_slide.html)