GRAIN SIZE ANALYSIS OF SOME OLISTOSTROMES BETWEEN BALKUYUMCU AND ALCI (SW ANKARA)

Yıl 1993, Cilt: 115 Sayı: 115, 31 - 48, 01.08.1993

Engin Olgun Teoman Norman

Öz

Sedimentary features and the detailed grain size analyses of six olistostromes (debris flows) have been
examined; they are located between Alcı and Balkuyumcu villages, 40 km. southwest of Ankara. Photograph-grid method and
sieving methods are used for gram size distribution analyses. The distribution of clast sizes within olistostromes are shown as
histograms and cumulative curves. After calculating the main gram size parameters, their relations with respect to each other
are examined on distribution diagrams (scatter diagrams). So, some of the distinguishing characteristics of olistostrome clast
size distributions have been established. Studies on the clast size distribution and clast roundness indicate that, olistostromes
are, in general, very poorly sorted, either negatively or positively skewed, mostly platykurtic. Clasts are angular to sub angular.
Generally, scatter plots of grain size parameters of olistostromes are distinct when compared with other sedimentary deposits.

Anahtar Kelimeler

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Kaynakça

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