Analyzing fracture stratigraphy

Patent metadata

Field	Value
Publication number	US-9377547-B2
Application number	US-201213646093-A
Country	US
Kind code	B2
Filing date	Oct 5, 2012
Priority date	Oct 5, 2012
Publication date	Jun 28, 2016
Grant date	Jun 28, 2016

Abstract

Systems, methods, and software can be used to calculate fracture stratigraphy of a subterranean zone. In some aspects, microseismic event data associated with a fracture treatment of a subterranean zone are received, and the subterranean zone includes multiple subsurface layers. A filter is used to select a subset of the microseismic event data corresponding to fractures in a particular subsurface layer. Fracture stratigraphy is calculated for the particular subsurface layer from fracture planes associated with the selected subset of the microseismic event data.

First claim

The invention claimed is:

1. A computer-implemented method for identifying fracture stratigraphy based on microseismic data, the method comprising:
receiving microseismic event data associated with a fracture treatment of a subterranean zone, the subterranean zone including a plurality of subsurface layers;
using a filter to select a subset of the microseismic event data, the selected subset of the microseismic event data associated with a particular subsurface layer in the subterranean zone, wherein the filter includes filter parameters that define a specified region within the particular subsurface layer, wherein using the filter to select the subset of the microseismic event data includes identifying microseismic events in the specified region;
generating, by data processing apparatus, a plurality of fracture planes based on the selected subset of microseismic event data associated with the identified microseismic events in the specified region within the particular subsurface layer;
calculating, by data processing apparatus, a fracture stratigraphy for the particular subsurface layer, wherein the fracture stratigraphy is calculated from the fracture planes generated using the selected subset of the microseismic event data associated with the identified microseismic events in the specified region within the particular subsurface layer; and
correlating the calculated fracture stratigraphy with mechanical stratigraphy for the particular subsurface layer, wherein correlating the calculated fracture stratigraphy with mechanical stratigraphy for the particular subsurface layer comprises comparing spatial variations in the calculated fracture stratigraphy with spatial variations in mechanical properties of rock in the particular subsurface layer of the subterranean zone; and
controlling an injection treatment based on the calculated fracture stratigraphy.

2. The method of claim 1 , wherein using the filter to select the subset of the microseismic event data includes identifying microseismic events associated with fracture planes intersecting the specified region, and the fracture stratigraphy is calculated for the specified region based on the identified microseismic events associated with fracture planes intersecting the specified region.

3. The method of claim 2 , wherein at least one of the fracture planes intersects the specified region and at least one other subsurface layer, and the identified microseismic events include at least one microseismic event in the other subsurface layer.

4. The method of claim 1 , wherein the filter parameters define the specified region as a range of vertical depth.

5. The method of claim 1 , further comprising:
generating a user interface that includes a graphical representation of the particular subsurface layer of the subterranean zone and locations of microseismic events; and
receiving, through the user interface, a user selection of the filter parameters.

6. The method of claim 1 , wherein calculating fracture stratigraphy comprises at least one of:
generating a statistical description of fracture orientations for fracture planes associated with the particular subsurface layer;
generating a statistical description of fracture spacing for fracture planes associated with the particular subsurface layer; or
generating a statistical description of fracture dip angles for fracture planes associated with the particular subsurface layer.

7. The method of claim 1 , wherein the selected subset of the microseismic event data includes all microseismic events in the particular subsurface layer.

8. The method of claim 1 , wherein the selected subset of the microseismic event data includes a less than all microseismic events in the particular subsurface layer.

9. The method of claim 1 , wherein the selected subset of the microseismic event data includes all fracture planes in the particular subsurface layer.

10. The method of claim 1 , wherein the selected subset of the microseismic event data includes a less than all fracture planes in the particular subsurface layer.

11. A non-transitory computer-readable medium encoded with instructions that, when executed by data processing apparatus, perform operations comprising:
receiving microseismic event data associated with a fracture treatment of a subterranean zone, the subterranean zone including a plurality of subsurface layers;
using a filter to select a subset of the microseismic event data, the selected subset of the microseismic event data associated with fracture planes in a particular subsurface layer in the subterranean zone, wherein the filter includes filter parameters that define a specified region within the particular subsurface layer, wherein using the filter to select the subset of the microseismic event data includes identifying microseismic events in the specified region;
generating a plurality of fracture planes based on the selected subset of microseismic event data associated with the identified microseismic events in the specified region within the particular subsurface layer;
calculating a fracture stratigraphy for the particular subsurface layer, wherein the fracture stratigraphy is calculated from the fracture planes generated using the selected subset of the microseismic event data associated with the identified microseismic events in the specified region within the particular subsurface layer; and
correlating the calculated fracture stratigraphy with mechanical stratigraphy for the particular subsurface layer, wherein correlating the calculated fracture stratigraphy with mechanical stratigraphy for the particular subsurface layer comprises comparing spatial variations in the calculated fracture stratigraphy with spatial variations in mechanical properties of rock in the particular subsurface layer of the subterranean zone; and
controlling an injection treatment based on the calculated fracture stratigraphy.

12. The computer-readable medium of claim 11 , wherein the filter includes parameters that define a specified region within the particular subsurface layer, using the filter to select the subset of the microseismic event data includes identifying microseismic events associated with fracture planes intersecting the specified region, and the fracture stratigraphy is calculated for the specified region based on the identified microseismic events.

13. The computer-readable medium of claim 11 , wherein calculating fracture stratigraphy comprises at least one of:
generating a statistical description of fracture orientations for fracture planes associated with the particular subsurface layer;
generating a statistical description of fracture spacing for fracture planes associated with the particular subsurface layer; or
generating a statistical description of fracture dip angles for fracture planes associated with the particular subsurface layer.

14. A system comprising:
a computer-readable non-transitory medium that stores microseismic event data associated with a fracture treatment of a subterranean zone, the subterranean zone including a plurality of subsurface layers; and
data processing apparatus operable to:
use a filter to select a subset of the microseismic event data, the selected subset of the microseismic event data associated with a particular subsurface layer of a plurality of subsurface layers in the subterranean zone, wherein the filter includes filter parameters that define a specified region within the particular subsurface layer, wherein using the filter to select the subset of the microseismic event data includes identifying microseismic events in the specified region;
generate a plurality of fracture planes

Assignees

• Halliburton Energy Services Inc

Inventors

• Williams Kenneth E
• Ma Jianfu
• Lin Avi

Classifications

• G01V1/288 Primary

  Event detection in seismic signals, e.g. microseismics (G01V1/36 takes precedence) · CPC title

• G01V2210/646

  Fractures · CPC title

• E21B43/26

  by forming crevices or fractures · CPC title

• G06F30/20

  Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) · CPC title