Friday, October 31, 2014

DFDP-2 @ 396 m: Calamity! Dropped bottom-hole-assembly (BHA)

Rupert Sutherland, GNS Science and Victoria University of Wellington
John Townend, Victoria University of Wellington
Virginia Toy, University of Otago

Drill site 22/10/2014  Photo J. Thomson
We removed the drill from the hole last Thursday (23/10/2014) at a depth of 396 m, so that we could survey the hole and reconfigure the drill. The wireline logging survey went smoothly. It is about 56 degrees Celsius near the bottom of the hole.

Wireline logging tool. Photo: J. Thomson.
The drill bit was found to be worn and the hole had reached 12° off vertical. The deviation was caused by mechanical interaction between the drill and the dipping rock fabric. At least it was heading in the right direction (northwest, towards the fault).

Worn PDC drill bit. Photo: R. Sutherland
 Tricone bit, collars, and stabilisers. 
24/10/2014 Photo: R. Sutherland.

The drilling team reconfigured the drill pipe and switched to a new drill bit. This time we used a tri-cone type of bit. The bit is attached to heavy, rigid ‘collars’, and wider pieces of pipe called ‘stabilisers’ that centralize them in the hole. The entire ‘bottom-hole assembly’ (BHA) weighs 7400 kg in mud and is 72 m long. It is connected to the surface with steel drill pipes.

Fishing tool and fragment of
recovered wire rope. 
Photo: R. Sutherland.

Calamity struck at 13:09 last Friday afternoon (24/10/2014), just before the Labour Day long weekend. A wire rope snapped and the entire BHA dropped down the hole. We are very relieved that nobody was hurt. An independent technical investigation is being conducted by an engineer and we await his findings.

Our immediate strategy is to try and retrieve the BHA from the hole. This process is known as ‘fishing’. The BHA weighs 7.4 tons, so the first step in fishing is to extricate anything preventing a good grip. The drillers were successful in fishing out of the hole some broken fragments of wire rope and some of the top fixings. They are now working to establish whether they can lower a socket over the top of the BHA. If that is possible, they will use a special tool used in the oil drilling world to lock onto the BHA and lift it back to the surface. This tool is being transported from New Plymouth.

Fishing tool 30/10/2014  
Photo: J. Townend.

What does this mean for the project? It is certainly going to delay progress, but everyone is working hard to recover and continue. While fishing operations are underway, we have been analysing the data collected so far and documenting our preliminary findings.

If the BHA cannot be retrieved, we will cement it in place and side-track (deviate) the hole above it. This will mean re-drilling about 100 m of hole, but we can re-use most of the steel casing already installed.
We had expected delays of some sort from the outset, so we have contingency built into our scheduling. The delays so far mean that the project will continue into December, and we are very much hoping to get back on track so that we can finish before Christmas.

Nobody said it would be easy!

Check out our new video that shows you what a bottom-hole-assembly actually looks like before it is assembled and put in the hole...

Check out our video that describes the purpose of the DFDP project...

Some comedians did a parody of the safety of our project last week, but is it safe? We think it is, but don't take our word for it. See the video made by the Chairman of our independent Safety Panel...

See also:
The DFDP-2 wiki pages

Primary funders of the DFDP-2 project are: the International Continental Scientific Drilling Program (ICDP), the Marsden Fund of the Royal Society of New Zealand, GNS Science, Victoria University of Wellington, and the University of Otago.


  1. Love your website design, colour. I procrastinate a whole lot and never manage to get anything done.
    kerala houseboat


  2. كنت أكثر من سعيد للكشف عن هذا الموقع الرائع. أريد أن أشكرك على وقتك بسبب هذه القراءة الرائعة !! لقد استمتعت بكل تأكيد بكل ما أوتيت من إشارة مرجعية لرؤية معلومات جديدة على مدونتك.
    نقل اثاث بالشارقة

  3. I hope it will be helpful for almost all peoples that are searching for this type of topic. I Think this website is best for such topic. good work and quality of articles Thanks
    Shakti Video Episode

  4. Wonderful goods from you, man. I have understand your stuff previous to and you’re just extremely great.I actually like what you’ve acquired here, certainly like what you are stating and the way in which you say it. You make it entertaining and you still care for to keep it wise.I can’t wait to read far more from you. This is actually a terrific website.
    Namah Video Episode

  5. I was more than happy to uncover this great site. I need to to thank you for your time due to this fantastic read! If you want to search best movers and packers Best Furniture Packers Movers In Abu Dhabi. I definitely enjoyed to give the answer of this and this article I really enjoy every bit of it and I have you bookmarked to see new information on your blog.
    نقل اثاث ابوظبي

  6. Professional movers and packers in dubai Aw, this was a very nice post. Taking the time and actual effort to produce a superb article… but what can I say… I procrastinate a whole lot and never manage to get anything done. professional movers and packers in dubai and cheap movers and packers in dubai is a Registered Company in Dubai.
    Cheap movers and packers in Dubai

  7. I think that is among the such a lot vital information for me.
    And i’m glad studying your article. But should remark on few normal issues, The website taste is great, the articles are really excellent : D. Good activity, cheers
    cheap moving companies in dubai

  8. درب ضد سرقت ارزان گزینه مناسبی برای افزایش امنیت خانواده های ایرانی است

  9. چگونه عمر ایزوگام خود را دو برابر کنیم؟
    مسئله عمر ایزوگام ارتباط زیادی به نحوه نگهداری و مراقبت از این عایق رطوبتی دارد.


  10. ال جی سرویس ارور ماشین لباسشویی ال جی یا همان کد خطای لباسشویی الجی را در مدلهای مختلف ، همراه با عیب یابی و دلیل خطا شرح داده است ، تا چنانچه بر روی صفحه نمایش لباسشویی الجی خود اروری مشاهده نمودید، چنانچه مشکل جزئی است به تعمیر لباسشویی ال جی خود بپردازید یا برای استفاده از خدمات و تعمیرکار الجی از نمایندگی تعمیرات ال جی بهره مند شوید.

  11. قیمت انواع حفاظ شاخ گوزنی نسبت به حفاظ‌های سرنیزه‌ای و آبشاری بیشتر است و به طور کلی قیمت این نوع حفاظ دیوار با توجه به تعداد شاخه ها، ارتفاع و عرض حفاظ، و کیفیت ساخت آن تعیین می‌شود.

    کلیک نمایید

  12. Assistir Online Assistir Big Brother Brasil completo em HD. Mais recente transmita Grátis online ou baixe Assistir Novelas ao vivo.

  13. The advantages of geothermal drilling rig are numerous. It offers a reliable and constant source of power, unlike solar and wind energy, which are subject to weather conditions. This baseload capability can play a crucial role in stabilizing our energy grids. Additionally, geothermal plants have a relatively small land footprint and produce minimal greenhouse gas emissions once operational, making them an environmentally friendly option.