BP 的Argos平台的吨位远超 60,000 吨，是美国墨西哥湾 (GOM) 深水区的巨头中的巨头。该平台高 27 层，平台长度和宽度相当于美式橄榄球场，是 BP 在该地区最大的平台之一。KBR 的前子公司 GVA 设计了这艘半潜式钻井平台，它是这家超级巨头耗资 90 亿美元的 Mad Dog II 项目的核心部分，该项目旨在释放中新世油藏的额外生产潜力，估计可容纳超过 50 亿桶石油。

但这并不总是计划。

十多年前，英国石油公司的疯狗二号看起来完全不同。从理论上讲，该生产商正在考虑一项全海底开发项目，该项目与另一个大型圆石平台（称为“ Big Dog” ）相连，以容纳额外的储量。该开发计划设想了一个巨大的桁架梁。

Tipping the scales at well over 60,000 tons, BP’s Argos platform is a giant among giants in the deepwater US Gulf of Mexico (GOM). Standing 27 stories tall, the platform has a deck the length and width of an American football field and is one of BP’s largest in the region. One-time KBR subsidiary GVA designed the semisubmersible, the centerpiece of the supermajor’s $9 billion Mad Dog II project built to unlock additional production potential of the Miocene-aged reservoirs estimated to hold more than 5 billion bbl of oil in place.

But that wasn’t always the plan.

Over a decade ago, BP’s Mad Dog II looked quite different. On paper, the producer was looking at an all-subsea development tied back to another large spar platform—dubbed Big Dog—to host the additional reserves. The development plan envisioned a massive truss spar.