Research On Formation Stability Profile Of Haituozi Area

There are many difficulties in drilling horizontal well in Haituozi area. So we carried out the study of drilling fluid with the function of anti-sloughing and anti-leaking in horizontal well. On the focus of smooth horizontal well drilling and well productivity improvement, we do a series of research on Nenjiang group, Yaojia group, Qingshankou group and Quantou group in Haituozi area, such as clay mineral analysis, physical and chemical property analysis and hole stability analysis. Finally, we got a conclusion that the upper side of Haituozi area has a high content of montmorillonite. This part belongs to moderate hydrate swelling formation. The lower-middle part mainly contains andreattite, and develops many bedding fractures. It belongs to hard brittle shale formation. The clay mineral disperses easily when contacting with water. The drilling fluid can penetrate into formation along the microcracks to form a thicker hydration film. This film can produce larger hydration repulsion. For this reason, the formation will collapse easily. On the whole, the formation performs weak/moderate swelling and moderate/strong dispersion. It’s easy to collapse. We studied and proposed the hole stability profile of Haituozi area. This profile can provide full, accurate and systematic basic data to study anti-slough and anti- leaking drilling fluid system for Haituozi area. As a result, we can realize the goal that safely and fast drill horizontal wells in Haituozi area. Also save the drilling cost effectively. Above all, improve well productivity and development effect.