Help on No of wells

[petro]

hello all,

is there any well-illustrated document or someone can explain how to deterine the required no of wells to deplete a reservoir.

thanks!

[FANARCO]

From analogue (nearby fields) producing from the same reservoir you have an idea of well spacing.

From well spacing you know the average drainage radius per well and then you can calculate the drainage area / well

In your respective field you have the area in Acre

Divide the whole area on the area/well will come up with the number of wells

[petro]

Thank you Fanarco,

I think it is not only the drainge area, properties like permeability may play a role in determine number of wells. Low k reservoir, not the same as high K reservoir.

thanks!

[FANARCO]

Thank you Fanarco,

I think it is not only the drainge area, properties like permeability may play a role in determine number of wells. Low k reservoir, not the same as high K reservoir.

thanks!

The method i mentioned above if case you don't have any data for your field/prospect or you are in exploration phase. And conditioned to have the same expected properties.

If you have a well and reservoir data there is another method by Darcy equation in radial flow and estimate Re.

A third way if you know any idea about average EUR/well.....

Actually, to choose which way depends on the available data.

Let me share with you some material related to this topic tomorrow.

[petro]

Thank you Fanarco,

I think it is not only the drainge area, properties like permeability may play a role in determine number of wells. Low k reservoir, not the same as high K reservoir.

thanks!

The method i mentioned above if case you don't have any data for your field/prospect or you are in exploration phase. And conditioned to have the same expected properties.

If you have a well and reservoir data there is another method by Darcy equation in radial flow and estimate Re.

A third way if you know any idea about average EUR/well.....

Actually, to choose which way depends on the available data.

Let me share with you some material related to this topic tomorrow.

thank you for quick reply,

will wait for the material to read.

[FANARCO]

The below table provide you with the Primary Recovery in Stock Tank Barrels per Acre-foot per Percent Porosity for Depletion type Reservoirs.

For example if you have a well proposed to drain a sandstone reservoir with 15 % porosity and expected GOR 600 SCF/STB and 30 API, so from the table the expected range is 3.61 to 10.48

So, the expected EUR per well = 3.61 x 15 (porosity) x 100 (area in acre) x 30 (thickness in ft) = 162,450 STB (0.162 MM STB) ...... Minimum value

And vise verse for maximum and average

Now you know the EUR per well..

For the field you know the OIIP and Recovery Factor and hence the total EUR per field.

Divide the field EUR on EUR per well, this will come up with Number of well

[petro]

The below table provide you with the Primary Recovery in Stock Tank Barrels per Acre-foot per Percent Porosity for Depletion type Reservoirs.

For example if you have a well proposed to drain a sandstone reservoir with 15 % porosity and expected GOR 600 SCF/STB and 30 API, so from the table the expected range is 3.61 to 10.48

So, the expected EUR per well = 3.61 x 15 (porosity) x 100 (area in acre) x 30 (thickness in ft) = 162,450 STB (0.162 MM STB) ...... Minimum value

And vise verse for maximum and average

Now you know the EUR per well..

For the field you know the OIIP and Recovery Factor and hence the total EUR per field.

Divide the field EUR on EUR per well, this will come up with Number of well

This is a good material,

Thank you for your time and help!

Regards!