Keywords : Northern Iraq

New Classopollis Species From Triassic-Jurassic Boundary In Northern Iraq

Iraqi National Journal of Earth Sciences, 2018, Volume 18, Issue 2, Pages 49-60

A new Classopollis species are described from Upper Triassic- Lower Jurassic Butmah Formation in borehole Tel-Hajar-1- northern Iraq. These are Classopollis scabratus, Classopollis polygonus, Classopollis microgranulatus, Classopollis zonatus and Classopollis crescentus; these taxa reveal distinctive morphologic features which lead to regard them as a new species..

The Effect of Some Engineering Properties of Rocks on Stress Distribution around the Proposed Sheikh Ibrahim Tunnel -SouthJazirah Irrigation Project- Northern Iraq

Azealdeen S. Al-Jawadi Hadeer G. M. Adeeb

Iraqi National Journal of Earth Sciences, 2010, Volume 10, Issue 2, Pages 1-18

This paper tackles engineering properties of rocks and stress distribution
around the assumed tunnel at the proposed site of the Sheikh Ibrahim Tunnel,
South Jazirah Irrigation Project, North of Iraq. A full description has been obtained
depending on available records, that taken from the executed soil investigation
reports of the project. The investigations were done in two stages: the first was the
field investigation and the second was the laboratory. The rock mass in Sheikh
Ibrahim tunnel mainly consists of evaporite, carbonate, and clastic rocks (marl,
sandstone and claystone). Engineering properties have been determined and
evaluated through (13) boreholes as previously mentioned in the records and then
to establish the preliminary design of the tunnel. The data of (129) rock samples,
that conclude laboratory testing (mechanical, dynamical, physical) and field testing
( study of fractures and permeability test), have been used in stress and distribution
analysis around the assumed 10 meters diameter tunnel by using the two
dimensional finite element analysis program.

The Fold Style Variations of Baikher Anticline - Northern Iraq

Safwan T. Al-Hubiti; Nabeel K. Al-Azzawi

Iraqi National Journal of Earth Sciences, 2009, Volume 9, Issue 1, Pages 1-20

The changes in fold style of Baikher Anticline were obtained by determining the fold shape, the values of interlimb angle and the degree of cylindricity in four cross-sectional traverses. The fold shape was calculated mathematically using the Fourier analysis method whereas the Ramsay and Huber classification method was applied for deciphering the cylindricity of the fold and the Pi-diagrams for determining the values of interlimb angle in each traverse.
The axial changes of the fold style revealed that the area that is occupied by Baikher Anticline was divided structurally into four segments according to their trend and vergence besides their comparison laterally with the related faults.
Data analysis revealed that Baikher Anticline is double plunging, asymmetrical, open to gentle and cylindrical in the four segments, whereas the fold vergence and shape differ from a segment to another. Baikher Anticline is verged southwestwards in the first and third segments, northeastwards in the second segment and northwards in the forth one. The analyses revealed that the fold shape ranges from chevron to box shape from traverse to another.
The anticline related faults fall into two categories. The first is a set of strike-slip type which influenced the fold trend whereas the second is listric faults that affected the fold vergence.
Vertical investigations of fold style were also carried out in the second and third traverses. The second traverse proved the Middle Eocene reactivation of the foreland listric fault, whereas unexpected vergences showed in the third one.