Ultra-deepwater reservoirs are important non-conventional reservoirs that hold
the potential to produce billions of barrels of hydrocarbons but present major
challenges. Hydraulic fracturing or frac-packing high permeability reservoirs is
different from the conventional hydraulic fracturing technology used in low
permeability formations. While the main purpose of the conventional technique is to
create a long, highly conductive path, frac-packing on the other hand is used predominantly
to get past near wellbore formation damage, control sand production and
reduce near wellbore pressure drop. Ultra-deepwater reservoirs are usually high
temperature and high pressure with high permeabilities. Frac-packing these types of
wells requires short fractures packed with high proppant concentrations.
Understanding the behavior of the fracture fluid and proppant is critical to pump such a
job successfully and to ensure long term productivity from the fracture.
A series of laboratory experiments have been conducted to research the
different problems resulting from high temperature and pressure which negatively
affect conductivity. Unlike conventional long-term conductivity measurements, we placed the proppant into the fracture and pumped fracture fluid through it and then
measured conductivity by pumping oil to represent true reservoir conditions. Proppant
performance and fracture fluids clean-up during production were examined. High
strength proppant is ideal for deep fracture stimulations and in this study different
proppant loadings at different stresses were tested to measure the impact of crushing
and embedment on conductivity.
The preliminary test results indicated that oil at reservoir conditions does
improve clean-up of fracture fluid left back in the proppant pack. Increasing the
proppant concentration in the fracture showed higher conductivity values even at high
closure stress. The increase in effective closure stress with high temperature yielded
significant loss in conductivity values as compared to those obtained from industry
tests.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/ETD-TAMU-2009-08-6977 |
| Date | 2009 August 1900 |
| Creators | Fernandes, Preston X. |
| Contributors | Zhu, Ding |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Thesis, text |
| Format | application/pdf |
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