Question

From the following, choose the offshore platform that can be used ONLY for offshore drilling purpose.

• A. Jacket platform
• B. Jackup platform
• C. Tension leg platform
• D. SPAR

Hint:

Think about mobility and purpose. If a platform is easily movable and self-installing like a jackup or a semi-submersible rig, it's likely a drilling unit. If it's permanently fixed (Jacket) or moored for a very long term (TLP, SPAR, FPSO), it's a production platform.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
The question asks to identify an offshore platform type that is used exclusively for drilling, not for long-term production of oil and gas. This requires knowledge of the different types of offshore structures and their primary functions.
Step 2: Detailed Analysis of Each Platform Type:
- (A) Jacket platform: This is a fixed platform with a steel lattice structure (the "jacket") piled into the seabed. Jacket platforms are very common and are designed for long-term production (and often drilling as well) in shallow to medium water depths. They are not exclusively for drilling.
- (B) Jackup platform (or Jackup rig): This is a mobile offshore drilling unit (MODU). It consists of a buoyant hull and a number of movable legs. It is towed to the location with its legs up, and then the legs are jacked down onto the seabed, lifting the hull out of the water. Jackups are used for exploratory drilling. Once drilling is complete, the well is either suspended or completed with a production structure, and the jackup rig moves to a new location. It is a temporary installation used ONLY for drilling.
- (C) Tension leg platform (TLP): This is a floating platform tethered to the seabed by vertical tensioned "tendons." TLPs are used for long-term production in deep water. They are stable platforms that can support both drilling and production facilities. They are not exclusively for drilling.
- (D) SPAR: This is a deep-draft floating platform, consisting of a large-diameter vertical cylinder supporting a deck. SPARs are moored to the seabed and are used for long-term production in very deep water. They can also support drilling operations. They are not exclusively for drilling.
Step 3: Why This is Correct:
Among the options listed, the Jackup platform is the only one that is a mobile drilling rig designed for temporary installation for the sole purpose of drilling wells. The others (Jacket, TLP, SPAR) are types of fixed or floating production platforms designed for long-term operations at a single field.