Geometric Analysis of the Minor Structures in Iraqi Part of the Zagros Belt, NE Iraq

• Geometric analysis was carried out on part of the Zagros Belt, along the border between Iraq andIran, within rocks of Cretaceous age, which are composed of alternative sequences of competentand incompetent layers, and it contains a number of minor structures. The minor folds identifiedwithin the study area have different shapes, orientations and sizes, and exhibit high intensityfolding. Their wave length and amplitude range from few centimeters up to tens of meters. They areranged from gentle to tight according to the Fleuty, 1964 classification. Class 1B is dominated andfollowed by class 1C according to the Ramsay, 1967. The orientation of the minor folds, theirrelation with the major structures, variance in their shapes and sizes and difference interlimb angle,all indicate that they were developed progressively and in harmony with the major structuredevelopment. It can be concluded that the congruous and subcongruous minor folds weredeveloped successively during a single phase of deformation with simulation of variouscompressive stress directions (generally, at NE-SW and E-W), and the reorientation of the stressfield from one direction to another is attributed to the oblique collision between the Arabian andEurasian plates and to the anticlockwise rotation of the Arabian plate relative to Eurasian plate.

Subject headings

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Geologi (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Geology (hsv//eng)

Keyword

Geomertrical Analysis

Minor Folds

Zagros Belt

Applied Geology

Tillämpad geologi

Publication and Content Type

vet (subject category)

kon (subject category)