TECTONICS OF QUATERNARY TRAVERTINE ACCUMULATION AT AL-FATHA AREA IN MIDDLE IRAQ

Yıl 2009, Cilt: 138 Sayı: 138, 1 - 7, 01.07.2009

İbrahim S.al Jumaıly Nazar M. S. Numan

Öz

Travertine deposits accumulation at Al-Fatha area occupy a narrow belt of about 200 m width, within the en-echelon overlap of Makhul and Hemrine North anticlines plunge noses, in the central area of Iraq. The aim of this work is to elucidate the local structural and tectonic control on the development of these deposits in the area. Mesofracture analyses in the vicinity of these deposits revealed the effect of two orthogonal ten- sional joint sets and two extensional shear fracture systems, as well as a system of strike slip shear fractures in development of these deposits. The stress tensors deduced from these fractures ought to stem from the extensional regime that accompanied and postulated folding process in the area. Meanwhile, travertine precipitation in the area seems to be a substantial outcome of these extensional stresses. Alternatively, the step over zone between two segments of a northwest-southeast trending subsurface left lateral fault also, might be the preferred location for these deposits in this area. However, the existence of this fault was approved previously by geophysical investigation. The alignment of separated warm water springs along side with the Dicle River bank in the area seems to be the surface expression of this fault.

Anahtar Kelimeler

Travertine, tectonic emplacement

Kaynakça

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