A New comprehension of the Basement undulation in The North of Iraq Resorting to Geomagnetic Investigation

Abstract

Because there are no wells in Iraq that go down to the basement complex of igneous and metamorphic rocks which are thought to be aggregated during the Late Precambrian, so the current study is important in tracking the surface boundary with the sedimentary cover and try to identify the structural appearance and the effect of this in construction of the geological situation in the region. The geophysical survey included 87 magnetic measurements with implantation the required corrections as well as using the upward continuation to remove the noises that not required in the present study.

A quantitative interpretation has been made using Oasis Montaj program across five magnetic profiles (Tr1, Tr2, Tr3, Tr4, and Tr5) with control of well logging, gravity, and seismic information. The results showed varying depths of the basement rocks ranging from 10 km in the northeastern part (Aqra structure) to less than 6 km in the south-west of the study area. In addition, a number of grabens, half grabens and horsts have been simulated in the magnetic sections for the present study.

Keywords

• Magnetic survey,Basement rocks,2D modeling,Oasis montage,Northern Iraq

Jeomanyetik Araştırmayla Kuzey Irak'taki Temel Ondülasyonu İçin Yeni Bir Anlayış

Abstract

Irak'ta, Geç Prekambriyen dönemine ait olduğu düşünülen magmatik ve metamorfik kayalardan oluşan temel kompleksine kadar inen hiçbir sondaj kuyusu bulunmadığından dolayı, bu çalışma; tortul istifle olan sınırı ve yapısal nitelikleri izlemek ve bölgedeki jeolojik gelişimin anlaşılması açısından önemlidir. Jeofizik araştırmada 87 manyetik ölçü alınmıştır, verilere gerekli düzeltmelerin yanında bu çalışma kapsamında olmayan ve gürültü olarak nitelendirilebilecek etkiler yukarı analitik uzanım tekniğiyle giderilmiştir. 

Beş adet manyetik profil verisi için (Tr1, Tr2, Tr3, Tr4 ve Tr5) kuyu logu, gravite ve sismik bilgilerin kontrolünde Oasis Montaj programı kullanılarak nicel bir yorumlama yapılmıştır. Sonuçlar, temel kayaların çalışma alanının kuzeydoğu kesiminde (Aqra yapısı) 10 km'den çalışma alanının güneybatısındaki 6 km'den daha düşük bir seviyeye kadar değişen derinliklerini göstermiştir. Ayrıca, bu çalışmada manyetik kesitlerde bir dizi graben, yarı-graben ve horst simüle edilmiştir.

Keywords

• Manyetik araştırma,Temel kayalar,Oasis Montaj,2D modelleme,Kuzey Irak

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