Güvenli Çamur Ağırlık Penceresinin Değerlendirilmesi: Bir Kuyu Stabilite Analizi, Rumaila Petrol Sahası, Güney Irak

Yıl 2025, Cilt: 49 Sayı: 2, 77 - 100, 11.12.2025

Saad Saadi , Nihad Saoud Aljuboori , Mohammed Zainal Qader , Elaf Mohammed Shakir , Ahmed Ibrahim Saleh Alnaemi Ibrahim Saleh , Lizan Ahmed Saleh

Öz

Kuyu kararsızlığı, sondaj sürecinde ciddi operasyonel kesintilere ve mali kayıplara yol açarak petrol ve doğal gaz sektöründe ek üretimsiz zamanlara neden olur. Bu çalışma, kuyu tasarımını iyileştirmek amacıyla Irak’ın güneyindeki Rumaila petrol sahasında kuyu stabilitesi sorunlarının doğasını anlamak için yürütülmüştür. Çalışmanın amacı, bir boyutlu jeomekanik model oluşturmaktır. Modeli geliştirmek için açık kuyu loglarından elde edilen ölçümlere ihtiyaç duyulmuştur. Kuyu duvarının sağlam kalması için gerekli minimum çamur ağırlığını belirlemek ve kuyu genişlemelerini analiz etmek amacıyla Mohr–Coulomb, Mogi–Coulomb ve Modifiye Lade olmak üzere üç farklı yenilme kriteri kullanılmıştır. Jeomekanik modelin doğruluğunu artırmak için, kuyu için öngörülen duraysızlık profili, kaliper logu ile raporlanan gözlenen kuyu başarısızlığı ile karşılaştırılmıştır. Bulgular, çalışma alanında çamur ağırlığı aralığının alt sınırını tahmin etmede Mogi–Coulomb kriterinin diğer iki kriterden daha doğru sonuç verdiğini, dolayısıyla en uygun yöntem olduğunu göstermektedir. Kuyu duraysızlığı analizi, düşük eğimli ve 40°’den az sapmaya sahip dik kuyuların daha güvenli ve daha sağlam olduğunu ortaya koymuştur. Duraysızlıkların büyük bölümünü azaltmak için önerilen çamur ağırlığı 10,5 ppg’ye yükseltilmiştir. Elde edilen sonuçlar, incelenen bölgeye yakın kuyuların planlanmasına yardımcı olacak, böylece üretimsiz zamanların ve maliyetlerin azaltılmasına katkı sağlayacaktır.

Anahtar Kelimeler

Jeomekanik model , kuyu duyarsızlığı , tek boyutlu jeomekanik model , güvenli çamur ağırlık penceresi , Mogi-Coulomb kriteri

Evaluation of the Safe Mud Weight Window: Wellbore Stability Analysis, Rumaila Oilfield, Southern Iraq

Öz

Wellbore instability leads to severe operational interruption and financial losses during the drilling process, resulting in additional non-productive periods in the petroleum and natural gas sector. This study was undertaken to comprehend the nature of wellbore stability challenges at the Rumaila oilfield, southern Iraq for the purpose of enhancing well design. The aim of this study was to create a one-dimensional geomechanical model. Measurements from open hole well logs were required to create the model. Three failure criteria including Mohr-Coulomb, Mogi-Coulomb, and Modified Lade were utilized to figure out the minimum mud weight required for a solid (stable) wellbore wall and also to analyze borehole breakouts. To improve the precision of the geomechanical model, a comparison was made between the projected instability profile of the borehole with the observed failure of the borehole, as reported by the caliper log. The findings indicate that the Mogi-Coulomb criterion more accurately predicts well failure than the other two criteria, establishing it as the superior method for forecasting the rock lowest boundary of mud weight window in the study area. The study of wellbore instability indicated that low and vertical wells with a deviation of less than 40º are safer and more stable. The suggested mud weight was increased to 10.5 ppg to mitigate the majority of instability issues. The findings will aid in planning development for wells adjacent to the examined region, and hence reduce non-productive time and costs.

Anahtar Kelimeler

Geomechanical model , wellbore instability , one-dimensional geomechanical model , safe mud weight window , Mogi-Coulomb criterion

Etik Beyan

The authors have not disclosed any conflict of interest.

Teşekkür

Saadi and other authors would like to express gratitude to Mosul University, Mosul. Iraq for support in completing this work. For much fruitful cooperation on filed trips, laboratory work and reviews, we thank

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