In the article recently posted by TREE there was a report by the author that some entities in the industry may have E/A concerns that "the carbonate style of the reservoir makes it more challenging and risky for development", and that this factor might "require many more wells to get it out of the ground".

This hypothesis was quickly dismissed by some posters and I am not looking to get back into that type of discussion.  However, I would like to at least understand what it is that this might or might not mean.  Obvioulsy not all gas in the ground is created equal.  I have remedial understanding of the importance of connectivity, porosity, etc., but zero understanding with regard to what differing "carbonate styles" could mean in terms of commerciality.  It is obviously very technical and I don't recall any discussion about this.

Any insight, PET?

'CAC' pid='65763' datel Wrote:

In the article recently posted by TREE there was a report by the author that some entities in the industry may have E/A concerns that "the carbonate style of the reservoir makes it more challenging and risky for development", and that this factor might "require many more wells to get it out of the ground".

This hypothesis was quickly dismissed by some posters and I am not looking to get back into that type of discussion.  However, I would like to at least understand what it is that this might or might not mean.  Obvioulsy not all gas in the ground is created equal.  I have remedial understanding of the importance of connectivity, porosity, etc., but zero understanding with regard to what differing "carbonate styles" could mean in terms of commerciality.  It is obviously very technical and I don't recall any discussion about this.

Any insight, PET?

CAC, I think it's a very good question, referring to issues like connectivity and whether it's a water driver, but there are likely to be more parameters, it would be useful to know more about these.

(01-08-2016, 02:04 AM)CAC Wrote:

In the article recently posted by TREE there was a report by the author that some entities in the industry may have E/A concerns that "the carbonate style of the reservoir makes it more challenging and risky for development", and that this factor might "require many more wells to get it out of the ground".

This hypothesis was quickly dismissed by some posters and I am not looking to get back into that type of discussion.  However, I would like to at least understand what it is that this might or might not mean.  Obvioulsy not all gas in the ground is created equal.  I have remedial understanding of the importance of connectivity, porosity, etc., but zero understanding with regard to what differing "carbonate styles" could mean in terms of commerciality.  It is obviously very technical and I don't recall any discussion about this.

Any insight, PET?

'petrengr1' pid='65769' datel Wrote:

'CAC' pid='65763' datel Wrote:

In the article recently posted by TREE there was a report by the author that some entities in the industry may have E/A concerns that "the carbonate style of the reservoir makes it more challenging and risky for development", and that this factor might "require many more wells to get it out of the ground".

This hypothesis was quickly dismissed by some posters and I am not looking to get back into that type of discussion.  However, I would like to at least understand what it is that this might or might not mean.  Obvioulsy not all gas in the ground is created equal.  I have remedial understanding of the importance of connectivity, porosity, etc., but zero understanding with regard to what differing "carbonate styles" could mean in terms of commerciality.  It is obviously very technical and I don't recall any discussion about this.

Any insight, PET?

CAC- I think the article is misleading regarding the quality of the Antelope Field. I think you have it figured out, it is all about porosity and connectivity.

 I can visualize a carbonate gas reservoir that might have problems like they mention but I do not think the Antelope Field has those characteristics.

For example if the reservoir was highly compartmentalize it might require more wells. Since we have no evidence that Antelope is compartmentalized and since we have the recent connectivity test that shows that Antelope-1 and Antelope-5 are connected, I do not think Antelope is compartmentalized but even if it was that should not be a killer for the project. I believe the Arun Field was compartmentalized and required a large number of wells but it was still highly successful. We will need to produce about 1 BCF/day for a two train plant. As we know the Antelope wells have extremely high flow potential and the rate seems to be only limited by the size of the tubulars. It is not realistic to expect these wells to produce at rates of 300- 700 MMCFD but rates of 100 -200 MMCFD are achievable. If we plan to produce each well at 100 MMCFD we will only require 10 wells.

Another type of problem that could occur in a highly fractured low porosity limestone with a strong water drive is that the water might flow through the fractures and water out the producing wells without recovering the gas in the low porosity rock. As we know the “reserve calculators” did not give much gas volume to the Elk Field because the porosity is low in the only producing well that has been drilled i.e. Elk-1.

The Antelope Field is probably highly fractured which probably accounts for the extremely high flow rates with minimum pressure drawdown. But since we have porosity of up to 25% in the reefal part of the formation and since GLJ thinks we will have a pressure depletion type drive and very little if any water drive, I think the Antelope Field is likely to have a very high recovery factor and will require a minimum number of wells.

The Majors will always try to squeeze a smaller company to get the gas at the lowest possible price. For example Hession had to give Total the first 3.5 TCF at zero cost to get the deal they eventually signed. I suppose that is because that is the minimum amount of gas required for a one train plant. If such a scenario actually played out IOC would still get their percentage of sales from the plant.

**********

That is helpful.  Thank you, PET.

'petrengr1' pid='65769' datel Wrote:

'CAC' pid='65763' datel Wrote:

In the article recently posted by TREE there was a report by the author that some entities in the industry may have E/A concerns that "the carbonate style of the reservoir makes it more challenging and risky for development", and that this factor might "require many more wells to get it out of the ground".

This hypothesis was quickly dismissed by some posters and I am not looking to get back into that type of discussion.  However, I would like to at least understand what it is that this might or might not mean.  Obvioulsy not all gas in the ground is created equal.  I have remedial understanding of the importance of connectivity, porosity, etc., but zero understanding with regard to what differing "carbonate styles" could mean in terms of commerciality.  It is obviously very technical and I don't recall any discussion about this.

Any insight, PET?

CAC- I think the article is misleading regarding the quality of the Antelope Field. I think you have it figured out, it is all about porosity and connectivity.

 I can visualize a carbonate gas reservoir that might have problems like they mention but I do not think the Antelope Field has those characteristics.

For example if the reservoir was highly compartmentalize it might require more wells. Since we have no evidence that Antelope is compartmentalized and since we have the recent connectivity test that shows that Antelope-1 and Antelope-5 are connected, I do not think Antelope is compartmentalized but even if it was that should not be a killer for the project. I believe the Arun Field was compartmentalized and required a large number of wells but it was still highly successful. We will need to produce about 1 BCF/day for a two train plant. As we know the Antelope wells have extremely high flow potential and the rate seems to be only limited by the size of the tubulars. It is not realistic to expect these wells to produce at rates of 300- 700 MMCFD but rates of 100 -200 MMCFD are achievable. If we plan to produce each well at 100 MMCFD we will only require 10 wells.

Another type of problem that could occur in a highly fractured low porosity limestone with a strong water drive is that the water might flow through the fractures and water out the producing wells without recovering the gas in the low porosity rock. As we know the “reserve calculators” did not give much gas volume to the Elk Field because the porosity is low in the only producing well that has been drilled i.e. Elk-1.

The Antelope Field is probably highly fractured which probably accounts for the extremely high flow rates with minimum pressure drawdown. But since we have porosity of up to 25% in the reefal part of the formation and since GLJ thinks we will have a pressure depletion type drive and very little if any water drive, I think the Antelope Field is likely to have a very high recovery factor and will require a minimum number of wells.

The Majors will always try to squeeze a smaller company to get the gas at the lowest possible price. For example Hession had to give Total the first 3.5 TCF at zero cost to get the deal they eventually signed. I suppose that is because that is the minimum amount of gas required for a one train plant. If such a scenario actually played out IOC would still get their percentage of sales from the plant.

Pet - My "gigantic"thanks for your informative and excellant answer to Cac's question . You tactfully and brilliantly " covered all the bases" in your response. Well done,sir.