The Kenmac Petroleum Corporation is planning to drill a new vertical exploratory well in their newly licensed Molly field. This report covers the detailed description of tasks that are required to be carried out for well planning.
Table of Contents
1.0 Executive Summary
2.0 Introduction
3.0 Assumptions
4.0 Basis of Well Planning and Design
4.1 Drilling Rig Selection
4.2 Pore and Fracture Pressure Gradient Estimation
4.3 Anticipated Drilling Problems / Lithological Characteristics
4.4 Casing Scheme
4.5 Mud Programme
4.6 Cement Programme
4.7 Derrick Capacity
4.8 Well Safety Considerations
4.9 Completion Design
4.10 Well Schematic
5.0 Conclusion
6.0 References
7.0 Appendices
Objectives and Scope
The primary goal of this report is to provide a comprehensive well planning and drilling design for a new vertical exploratory well in the Molly field. It addresses the technical requirements for safe and efficient drilling, covering everything from rig selection to final completion design, while ensuring the project's economic viability and operational safety.
- Rig selection and operational suitability for the Molly field
- Estimation of pore and fracture pressure gradients for casing design
- Analysis of geological lithology and mitigation of drilling problems
- Design of mud and cementing programs for well integrity
- Safety protocols and completion design for reservoir extraction
Excerpt from the Book
4.3 Anticipated Drilling Problems / Lithological Characteristics:
The Molly field lithological column suggests carboniferous sedimentary depositions with each of the layers may pose its own peculiar drilling problems.
Table 3 below lists some of the anticipated drilling problems which can encounter while drilling the well through these formations.
Sea-bed – 650 ft. Silts & soft clays, Unconsolidated clays: Hole Problems – Unconsolidated clays form Gumbo at surface. Mitigation: Drill section with seawater sweeps.
650-4260 ft. Paleocene middle shales, clays and light sandstones: Formation water migrations may occur at the top ends of the Paleocene middle shales – Shallow water kicks can be expected. Wellbore instability due to reactive shales – stuck pipe. Mitigation: Diverter will be installed from start of drilling. Pre-treatment with suitable filter cake enhancing additive, combined with good drilling practices will be the main methods for avoiding stuck pipe.
Chapter Summaries
1.0 Executive Summary: Outlines the project scope for the Molly field exploration well, highlighting the selection of the Trident II rig and the core technical components of the drilling program.
2.0 Introduction: Defines the field location in the North Sea and details the specific objectives, including drilling safely, obtaining quality reservoir data, and completing the well with minimal damage.
3.0 Assumptions: Lists the general technical and regulatory parameters that serve as the foundation for the well planning process.
4.0 Basis of Well Planning and Design: Serves as the primary technical section, covering rig selection, pressure estimations, lithological challenges, casing, mud, cement, derrick capacity, and completion design.
5.0 Conclusion: Summarizes that the proposed well design effectively balances cost-efficiency with conservative safety standards across the entire life cycle of the well.
6.0 References: Lists the industry standards, handbooks, and communications used to support the technical calculations.
7.0 Appendices: Provides supporting documentation, including rig specifications and detailed computation models for mud, casing, and safety ratings.
Keywords
Well Planning, Molly Field, Trident II, Drilling Rig, Pore Pressure, Casing Scheme, Mud Programme, Cementing, Derrick Capacity, Well Safety, Completion Design, Carboniferous Siltstone, Formation Evaluation, Hydraulic Requirements, Well Integrity
Frequently Asked Questions
What is the primary purpose of this document?
The document serves as a detailed well planning report for a vertical exploratory well located in the Molly field, covering all essential technical engineering aspects required for drilling.
What are the central topics covered in this report?
Key topics include rig selection, pressure gradient estimation, casing and cementing design, mud programs, drilling risk mitigation, and completion procedures.
What is the central research question or project goal?
The goal is to design a cost-effective, safe drilling program that ensures maximum economic value and long-term well integrity for the target reservoir.
What scientific methods were used for planning?
The report utilizes industry-standard calculations for pore/fracture pressure estimation, Eaton’s equation, hydrostatic pressure modeling, and derrick capacity assessment.
What does the main body of the work focus on?
The main body focuses on the operational specifications needed to navigate the specific geological conditions of the Molly field, including managing Zechstein salts and formation pressures.
Which keywords best characterize this work?
Keywords include Well Planning, Casing Scheme, Mud Programme, Derrick Capacity, and Well Safety.
Why was the Trident II rig selected for this project?
The Trident II was chosen based on its ability to operate within the specific water depth of the Molly field, its required derrick capacity, and its compliance with weather parameter conditions.
How are drilling problems like stuck pipes mitigated?
Mitigation strategies include using salt-saturated mud, loss circulation material (LCM) treatments, seawater sweeps for unconsolidated clays, and proper jar placement in the Bottom Hole Assembly (BHA).
What is the significance of the cementing program described?
The cementing program is designed to provide effective zonal isolation and pressure containment, while accounting for the mobility of the Zechstein salt formations.
- Arbeit zitieren
- Aakanksha Sadekar (Autor:in), 2011, Well planning report for the Molly field exploration well, München, GRIN Verlag, https://www.grin.com/document/271887
