KAZAKHSTAN UPSTREAM OIL AND GAS technology and R&d ...

4.1 Drilling and well costs
Challenge commentary
Kazakhstan has some of the most complex
reservoirs in the world, containing oil and gas
at high pressures and temperatures, as well as
high levels of H 2
S and CO 2
. Drilling is always
going to be a challenge under these conditions.
On top of this, there are the practical and
logistical difficulties associated with the limited
internal infrastructure in parts of the country, lack
of a sea route for drilling equipment into the
country and the harsh winters.
Under the circumstances, rig safety is a
major challenge in Kazakhstan, undertaking
exploration or development drilling or well
intervention in a manner that reduces the
risk to the people involved as well as local
communities. The challenge is most acute in
fragile formations and where there are issues
of well integrity – the Kenkiyak, Korolev,
Kumkol South and North Buzachi fields are
examples. Casing pressure management is
also a safety-related issue in many fields,
especially in sedimentary sub-salt reservoirs
such as Karachaganak, Kenkiyak, Zhanazhol
and Alibekmola.
Drilling through low pressure zones is a
widespread challenge, given the prevalence
of carbonate reservoirs in Kazakhstan and
their tendency to contain cavities (vugs or
karsts) or otherwise low mechanical strength
rock structures. Mud loss, well bore stability
and pipe sticking are common problems
in, for example, Karachaganak, Kenkiyak,
Kumkol South and North Buzachi.
Given the drilling challenges faced in
Kazakhstan, well costs are generally high.
Drilling in shallow water generally entails
the construction of concrete drill pads. But
the main cost issues arise from the need to
bring every element of the drilling process
(rigs, tools and equipment, chemicals and,
not least, skilled people) into Kazakhstan.
Unsurprisingly, cost over-runs are common:
reducing their likelihood is a big challenge.
VALUE
CHALLENGE (elements)
Rig safety
4.1.7
4.1.1
4.1.2
4.1.3
4.1.4
4.1.5
4.1.6
TECHNOLOGY SOLUTIONS
4.1.1 Casing & liners with improved pressure
containment capabilities
4.1.2 Drilling through abnormal pressures,
high temperatures & H 2
S
ATTRACTIVENESS
4.1.3 Surface pressure control equipment for improved safety
(on land & shallow water)
4.1.4 Drilling safety methods
83
Drilling through low pressures
(losses, stability)
4.1.2 Drilling through abnormal pressures,
high temperatures & H 2
S
4.1.5 Cost effective drilling techniques
4.1.6 Directional drilling & reach
4.1.7 Improved drilling rigs with directional drilling capabilities
Reduce well costs
Kazakhstan Upstream oil & gas technology and R&D roadmap