일반명 : 충격암 (Impact Rock)
학명 (Crater Name) : Ternovka
발견지(Location) : Ukraine
위도(Latitude) : N 48° 08'
경도(Longitude) : E 33° 31'
운석공작용직경 : Diameter (km) : 11
만들어진시기: Age (Ma)* : 280 ± 10
Exposed(노출등급) : N
Drilled(천공등급) : Y
Target Rock** : C

MINERALOGICAL, GEOCHEMICAL AND GEOLOGICAL DATA FOR THE
INTERPRETATION OF THE CRATER BASE STRUCTURE OF THE COMPLEX
TERNY ASTROBLEME (KRIVOY ROG, UKRAINE). A. A. Valter, Malyshko Stra., 3,
apt. 449.

The deeply eroded (H ³ 0.8 km) Terny astrobleme was formed in the rocks of the Krivoy Rog iron formation and
related banded Lower Proterosoic metamorphic rocks and granitoids [1-4]. The present-day diameter of the structure is estimated to be 8 km, but the original one might be twice as large. The diameter of the eroded central uplift is about 2.5 km. In the exploration and prodaction of ores the sinking of quorries (to 350 m deep), mines (to 1 km deep), and boreholes were performed within the astrobleme.
The K-Ar age determination of glass impactites gave the value of 280±10 Ma.
The obsevations in the mines show that monoclinal -occurrence rocks were crashed into blocks and overturned "to be
pulled up" into the up lift area. As the depth exceeds 1 km the occurrence approch the normal value.
Numerous bodies of fine fragmented breccia which separate large blocks of rocks have a preffered orintation
which corresponds to the tectonic plan of the region. Thus the evidence of the breccia zones formation along the weakest and strained planes of the massif is receved.
The ferroginous glassy impactites near the center of the uplift are formed by the melting of ferroginous quartzities, shists and iron ores. The most impactide bodies are of complicated origin: the shock
metamorphism, rock crushing and mixing of fragments varying in shock alteration, and finally, secondary heating by the gaseous fluids. In these impactites the condensation of the Fe-Cr-Ni - phase with the composition approaching the eutectic one was found. The geochemical traces of the "meteorite explosion cloud" were observed down to the deepest level of the glassy impactite occurrence (850 m): 2.4 ppb of Ir (x 60 enrichment) and 86 ppm of Ni ((x 40 enrichment) and ration Ni/Co=12 and Ir/Au=2.
The veins of alkaline silicate impactites of the Western Part of the uplift occur in the microgneisses shists of similar composition. These impactites exhibited no significant meteorite material vontamination. The presents of impact diamond grains found in these veins shows that the impulse pressure is achived sufficient for silicate melting in the shock ware or the rarefaction wave. The models of impactite formation and mass dynamics in the crater base are proposed. Owning to a good exposure and the specific composition of the target rocks the Terny astrobleme can be used as a standard in the studies of large meteorite crater bases.