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Micrometeorites from the northern ice cap of the Novaya Zemlya archipelag

Russia: The first occurrence

Dmitry D. BADJUKOV1* and Jouko RAITALA2

1V. I. Vernadsky Institute of Geochemistry and Analytical Chemistry RAS, Kosygin Str.,119991, Moscow, Russia

2Astronomy, Department of Physical Sciences, P.O. Box 3000, FIN-90014 University of Oulu, Finland

*Corresponding author.

(Received 7 May 2002; revision accepted 28 February 2003)

Abstract–Glacial deposits at the margins of the ice cap of the northern island of the Novaya Zemlya archipelago, Russia, contain numerous spherules and rare scoriaceous particles thought to be extraterrestrial. The 1 Kyr old glacier has decreased in volume and coverage during the last 40 years, leaving the spherules contained in the ice at the margins of the glacier where they can be easily collected.

The spherules are similar in their appearance, texture, and mineralogy to cosmic spherules found in deep-sea sediments in Greenland and Antarctica. Silicate spherules have typical bar-like textures (75%) or porphyritic textures (15%), while other spherules are glassy (7%). The spherules from Novaya Zemlya are altered only slightly. There are spherules consisting of iron oxides, metal cores with iron oxide rims, a continuous network of iron oxide dendrites in a glass matrix, and particles rich in chromite (3%). Some spherules contain metal droplets and relict forsterite and low-Ca pyroxene...

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