Corallian Energy Limited

A private oil and gas appraisal and exploration company

8 MARCH 2019 - 07:00

Colter well and side-track: completion of drilling operations

As previously reported on 25 February 2019, the Colter well (98/11a-6) was drilled as a vertical well with the Ensco-72 jack-up rig and reached a Total Depth of 1870m MD in the Sherwood Sandstone. The well was drilled to appraise the 98/11-3 well, drilled in 1986 by British Gas, within the Colter Prospect. The 98/11a-6 well unexpectedly remained on the southern side of the Colter Prospect bounding fault but encountered oil and gas shows over a 9.4m interval at the top of the Sherwood Sandstone reservoir. A petrophysical evaluation of the LWD data has calculated a net pay of 3m. Similar indications of oil and gas were encountered in the 98/11-1 well, drilled in 1983 by British Gas, within the Colter South fault terrace. Provisional analysis of the new data indicates that the two wells may a share a common oil-water-contact having both intersected the down-dip margin of the Colter South prospect. Corallian’s most recent assessment of the Colter South Prospect prior to drilling the 98/11a-6 well had estimated a mean recoverable volume of 15 mmbbls. Further work will be required to refine this assessment with the new well data.


A decision was made by the Joint Venture to drill a side-track (98/11a-6Z) to the north to evaluate the Colter Prospect. The well has now been drilled to a Total Depth of 1910m MD and encountered the Sherwood Sandstone below the oil-water-contact of the 98/11-3 well. Initial evaluation of the data from both wells indicates that the Colter Prospect is smaller than pre-drill estimates. The Colter South discovery remains an opportunity to evaluate further as it is now areally more extensive than indicated by the pre-drilling mapping. In addition, the side-track encountered oil and gas shows in the Jurassic Cornbrash-Lower Oxfordian interval, the producing reservoirs in the Kimmeridge oilfield, and this provides an interesting potential target on trend to the west within the onshore licences held by the Joint Venture. The data from these well results and existing data will be incorporated to determine the best forward plan.


Corallian and its Joint Venture partners would like to thank the well operator Fraser Well Management, rig operator Ensco and all the many contractors who assisted with the drilling operations which have been completed safely in an environmentally sensitive area.

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25 february 2019 - 07:00

Colter well update

The Colter well (98/11a-6) has been drilled as a vertical well with the Ensco-72 jack-up rig and has reached a Total Depth of 1870m MD in the Sherwood Sandstone. The well is an appraisal of the 98/11-3 well, drilled in 1986 by British Gas, within the Colter Prospect.


The 98/11a-6 well unexpectedly remained on the southern side of the Colter Prospect bounding fault but encountered oil and gas shows over a 9.4m interval at the top of the Sherwood Sandstone reservoir. A petrophysical evaluation of the LWD data has calculated a net pay of 3m. Similar indications of oil and gas were encountered in the 98/11-1 well, drilled in 1983 by British Gas, within the Colter South fault terrace. Provisional analysis of the new data indicates that the two wells may a share a common oil-water-contact having both intersected the down-dip margin of the Colter South prospect. Corallian’s most recent assessment of the Colter South Prospect prior to drilling the 98/11a-6 well had estimated a mean recoverable volume of 15 mmbbls. Further work will be required to refine this assessment with the new well data.


The joint venture has commenced preparations to side-track the 98/11a-6 well. The side-track will be drilled directionally to a Sherwood Sandstone target within the Colter prospect on the northern side of the bounding fault, and will take approximately 2 weeks to complete.


It is encouraging that the well has confirmed a discovery in the Colter South Prospect. More work will be required to determine the resource potential within the structure and we look forward to the results of the side-track to evaluate the Colter Prospect. 

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6 February 2019 - 11:00

Spud of the Colter well

Corallian as Exploration Operator for Licence P1918 is pleased to report that drilling of the Colter exploration well (98/11a-6), using the Ensco-72 Jack-Up rig, commenced at 10:10 hrs on 6 February 2019. The drilling is expected to take approximately 3 weeks to reach a planned total depth of 1,830 metres. Following the completion of drilling operations the well will be evaluated and permanently plugged and abandoned.

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16 JANUARY 2019 - 09:35

2019 Drilling Programme Update

  

Our first well, 11/24b-4, on the Wick prospect has disappointingly not been successful. We have safely completed drilling operations and will now proceed to plug and abandon the well.


The 11/24b-4 exploration well has been drilled to a total depth of 1,000m. The objective of the well, the Beatrice Sandstone, was encountered at a depth of 933.5m but is water bearing. 


Provisional petrophysical analyses indicate that the Beatrice Sandstone has a gross thickness of 22.8m with 19.8m of net sandstone of 17.2% average porosity. 


The well had the highest risk in the Corallian portfolio with a pre-drill chance of success estimated at 30%, with trap integrity considered the greatest risk element, and this appears to be why the well failed. It was an exciting prospect with pre-drill Pmean Prospective Resources estimated at 26 million barrels of recoverable oil.
 

The 11/24b-4 well is Corallian’s first well as Exploration Operator and drilling operations have been completed safely, in an environmentally sensitive area with multiple stakeholders and complex regulations. 


We look forward to drilling the Colter appraisal well and will provide an update when drilling commences. We assess the pre-drill chance of success of the Colter well to be 58%. The pre-drill Pmean Prospective Resources are estimated at 23 million barrels of recoverable oil. Corallian holds a 49% interest.
 

We continue to make good progress with securing funding partners for two further wells in 2019, the Curlew-A appraisal well in licence P2396 and the Oulton West appraisal / exploration well in licence P2222. 

ENSCO-72

ENSCO-72

25 December 2018 - 08:00

Spud of the Wick well

Corallian as Exploration Operator for Licence P2235 is pleased to report that drilling of the Wick exploration well (11/24b-4) commenced at 00:45 hrs on 25 December 2018. The Ensco-72 drilling rig will be on location for approximately 3 weeks.

ENSCO-72

ENSCO-72