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The Vostochno-Messoyakhskoe field is the northernmost active continental field in the Russian Federation (Fig. 1). This field is located 250 km from the Arctic Circle, in the arctic climatic zone. Full production drilling only began in 2015 because of the field's geological complexity and lack of transportation structure. Weather conditions, such as strong winds and extremely low temperatures, can be hazardous to personnel and equipment. Additionally, this oil field has permafrost zones (400m from the surface) and low formation temperatures at the production zone. Also, because of permafrost zones, there is a high risk of thawing the wellhead formation. These conditions significantly affect which technologies can be applied during drilling and completion of the wells. Therefore, special cement designs are necessary to help reduce risks associated with low temperatures and permafrost zones in the Vostochno-Messoyakhskoe field. Production is further complicated by a gas layer at 720 to 820m true vertical depth (TVD) and high formation pore pressure. This can make the cement operations with the production casings difficult. While the TVD of the casing landing is not relatively deep, the measured depth (MD) in extended reach drilling (ERD) wells is significant (Fig. 2). ERD wells can challenge cement displacement efficiency (Sabins, 1990). Mud removal efficiency may not be enough to create a high-quality cement barrier and isolate formations from gas migration. Poor mud removal can affect future life of the wells and crude oil production. To perform remedial jobs, it is necessary to stop production for several days. Due to experience in performing remedial jobs in the Messoyakhskoe field, it is usually necessary to perform a few attempts of the remedial cementing operation to reach positive results. Therefore, the operator decided to utilize hydraulic packers to create a second barrier between the surface and production casings to help prevent gas migration to the surface, save time associated with remedial operations, and extend the life of future wells.

Cement bond logs in the Messoyakha field indicated only 65% achieved mud displacement, which resulted in poor zonal isolation, resulting in annular pressure and remediation. Casing standoff is the most important factor to achieving better mud displacement from the annular space. The wellbore profile and the presence of caverns have significant impact on casing standoff. At the same time, increased centralization, in some cases, has a critical impact on running the casing to planned depth. Analysis in the use of different types of centralizers, their spacing patterns, and placement on the casing in the horizontal wells in this field are detailed in addition to the results of trial operations.

Lost circulation (LC) is commonly encountered in drilling and cementing operations and can significantly contribute to non-productive time (NPT). An operator in the Kyumbinskoe Field faced this challenge in a fractured production section of the formation, and conventional LC solutions had been ineffective at achieving strict regulatory top of cement (TOC) requirements and satisfactory cement bonding. This paper describes the experience of utilizing foam cementing technology as a primary solution to solve a lost circulation issue on the project. For this project a foam cementing solution was designed to meet operational parameters for cementing a production casing in one stage (multi-stage tool was eliminated). Use of foam cementing technology helped to minimize losses experienced in all cementing operations previously on this project. CBL results were also improved. All Customer requirements were met: Planned Top Of Cement (TOC)Minimum losses during cementing operationsRig time savingImproving CBL results.