Figure 1.
Porosity distribution frequency.
Figure 1.
Porosity distribution frequency.
Figure 2.
Permeability distribution frequency.
Figure 2.
Permeability distribution frequency.
Figure 3.
Numerical simulation workflow.
Figure 3.
Numerical simulation workflow.
Figure 4.
The reservoir porosity model.
Figure 4.
The reservoir porosity model.
Figure 5.
The reservoir permeability model. (a) Permeability model in X and Y directions. (b) Permeability model in Z-direction.
Figure 5.
The reservoir permeability model. (a) Permeability model in X and Y directions. (b) Permeability model in Z-direction.
Figure 6.
Display of the target well inside the geological model.
Figure 6.
Display of the target well inside the geological model.
Figure 7.
Oil–water relative permeability curve.
Figure 7.
Oil–water relative permeability curve.
Figure 8.
Capillary pressure curve.
Figure 8.
Capillary pressure curve.
Figure 9.
The distribution of fractures without natural fractures. (a) Fracture propagation simulation results (No natural fractures). (b) Top view of fractures distribution (3D diagram (left), 2D diagram (right)).
Figure 9.
The distribution of fractures without natural fractures. (a) Fracture propagation simulation results (No natural fractures). (b) Top view of fractures distribution (3D diagram (left), 2D diagram (right)).
Figure 10.
Distribution of hydraulic fractures when the natural fracture angle is 0°. (a) Fracture propagation simulation results (0°). (b) Top view of fractures distribution (3D diagram (left), 2D diagram (right)).
Figure 10.
Distribution of hydraulic fractures when the natural fracture angle is 0°. (a) Fracture propagation simulation results (0°). (b) Top view of fractures distribution (3D diagram (left), 2D diagram (right)).
Figure 11.
Fracture network in two cases.
Figure 11.
Fracture network in two cases.
Figure 12.
Reservoir matrix pore pressure distribution with different fluid volumes.
Figure 12.
Reservoir matrix pore pressure distribution with different fluid volumes.
Figure 13.
The variation of bottom hole pressure at different fluid volumes.
Figure 13.
The variation of bottom hole pressure at different fluid volumes.
Figure 14.
The change in cumulative oil production under different fluid volumes.
Figure 14.
The change in cumulative oil production under different fluid volumes.
Figure 15.
The change in cumulative water production under different fluid volumes.
Figure 15.
The change in cumulative water production under different fluid volumes.
Figure 16.
The relationship of cumulative oil production and its increase under different fluid volumes.
Figure 16.
The relationship of cumulative oil production and its increase under different fluid volumes.
Figure 17.
Reservoir matrix pore pressure distribution with different shut-in times.
Figure 17.
Reservoir matrix pore pressure distribution with different shut-in times.
Figure 18.
The variation of bottom hole pressure at different shut-in times.
Figure 18.
The variation of bottom hole pressure at different shut-in times.
Figure 19.
The change in cumulative oil production under different shut-in times.
Figure 19.
The change in cumulative oil production under different shut-in times.
Figure 20.
The change in cumulative water production under different shut-in times.
Figure 20.
The change in cumulative water production under different shut-in times.
Figure 21.
The relationship of cumulative oil production and its increase under different shut-in times.
Figure 21.
The relationship of cumulative oil production and its increase under different shut-in times.
Figure 22.
The variation of bottom hole pressure at different original formation pressures.
Figure 22.
The variation of bottom hole pressure at different original formation pressures.
Figure 23.
The change and increase ratios in formation pressure under different original formation pressures.
Figure 23.
The change and increase ratios in formation pressure under different original formation pressures.
Figure 24.
The change in cumulative oil production under different original formation pressures.
Figure 24.
The change in cumulative oil production under different original formation pressures.
Figure 25.
The change in cumulative water production under different original formation pressures.
Figure 25.
The change in cumulative water production under different original formation pressures.
Figure 26.
Fracture network under different natural fracture angles.
Figure 26.
Fracture network under different natural fracture angles.
Figure 27.
Fracture network of 0° natural fracture.
Figure 27.
Fracture network of 0° natural fracture.
Figure 28.
Fracture network of 80° natural fracture.
Figure 28.
Fracture network of 80° natural fracture.
Figure 29.
Reservoir matrix pore pressure distribution with different natural fracture angles.
Figure 29.
Reservoir matrix pore pressure distribution with different natural fracture angles.
Figure 30.
Reservoir matrix pore pressure distribution with 0° natural fracture.
Figure 30.
Reservoir matrix pore pressure distribution with 0° natural fracture.
Figure 31.
The variation in bottom hole pressure at different natural fracture angles.
Figure 31.
The variation in bottom hole pressure at different natural fracture angles.
Figure 32.
The change in cumulative oil production under different natural fracture angles.
Figure 32.
The change in cumulative oil production under different natural fracture angles.
Figure 33.
The change in cumulative water production under different natural fracture angles.
Figure 33.
The change in cumulative water production under different natural fracture angles.
Table 1.
Table of reservoir and fluid properties parameters.
Table 1.
Table of reservoir and fluid properties parameters.
Type of Parameter | Value |
---|
Crude oil parameters | Viscosity of crude oil on Viscosity of crude oil in the subsurface/MPa·s | 6.12 |
Viscosity of crude oil in the subsurface/MPa·s | 1.5 |
Density of crude oil on the ground/(kg/m3) | 840 |
Oil volume factor | 1.293 |
Formation water parameters | Viscosity of formation water/MPa·s | 1 |
Volume factor of formation water | 1.02 |
Density of formation water/(kg/m3) | 1000 |
Reservoir parameters | Reservoir temperature/°C | 76 |
Original formation pressure/MPa | 15.8 |
Rock compression coefficient/MPa−1 | 7.69 × 10−4 |
Table 2.
The well structure design of well A1.
Table 2.
The well structure design of well A1.
Name of Pipe Column | Outer Diameter/mm | Wall Thickness/mm | Steel Grade | The Maxim Setting Depth/m | Cement Return Depth/m |
---|
Surface casing | 244.48 | 8.94 | J55 | 1189 | The ground |
Tubing casing | 139.70 | 7.72 | P110 | 4281 | - |
Table 3.
The physical and rock mechanics parameters.
Table 3.
The physical and rock mechanics parameters.
Parameters | Upper Interlayer | Oil-Bearing Formation | Lower Interlayer |
---|
Reservoir physical parameters | Formation Pressure/MPa | 15.8 | 15.8 | 15.8 |
Reservoir thickness/m | 8 | 15 | 8 |
Porosity/% | 2 | 9.9 | 2 |
Permeability/mD | 0.013 | 0.13 | 0.013 |
Rock mechanics parameters | Young’s modulus/GPa | 35 | 30 | 35 |
Poisson’s ratio | 0.35 | 0.2 | 0.35 |
Horizontal maximum principal stress/MPa | 38 | 36 | 40 |
Horizontal minimum principal stress/MPa | 30 | 28 | 32 |
Table 4.
Perforation data of well A1.
Table 4.
Perforation data of well A1.
Section Number | Cluster Number | Top Depth/m | Bottom Depth/m | Thickness/m | Spacing/m |
---|
1 | 1 | 2736 | 2741 | 5 | 13 |
2 | 2723 | 2728 | 5 | 13 |
3 | 2710 | 2715 | 5 | 13 |
2 | 1 | 2681 | 2686 | 5 | 13 |
2 | 2668 | 2673 | 5 | 13 |
3 | 2655 | 2660 | 5 | 13 |
3 | 1 | 2626 | 2631 | 5 | 13 |
2 | 2613 | 2618 | 5 | 13 |
3 | 2600 | 2605 | 5 | 13 |
4 | 1 | 2571 | 2576 | 5 | 13 |
2 | 2558 | 2563 | 5 | 13 |
3 | 2545 | 2550 | 5 | 13 |
5 | 1 | 2516 | 2521 | 5 | 13 |
2 | 2503 | 2508 | 5 | 13 |
3 | 2490 | 2495 | 5 | 13 |
6 | 1 | 2461 | 2466 | 5 | 13 |
2 | 2448 | 2453 | 5 | 13 |
3 | 2435 | 2440 | 5 | 13 |
7 | 1 | 2406 | 2411 | 5 | 13 |
2 | 2393 | 2398 | 5 | 13 |
3 | 2380 | 2385 | 5 | 13 |
8 | 1 | 2351 | 2356 | 5 | 13 |
2 | 2338 | 2343 | 5 | 13 |
3 | 2325 | 2330 | 5 | 13 |
9 | 1 | 2296 | 2301 | 5 | 13 |
2 | 2283 | 2288 | 5 | 13 |
3 | 2270 | 2275 | 5 | 13 |
10 | 1 | 2241 | 2246 | 5 | 13 |
2 | 2228 | 2233 | 5 | 13 |
3 | 2215 | 2220 | 5 | 13 |
Table 5.
Parameters of natural fracture.
Table 5.
Parameters of natural fracture.
Types | Names | Length/m | Angle/° |
---|
No natural fracture | - | - | - |
Change the angle of natural fractures | FN1 | 30 | 0 |
FN2 | 30 | 20 |
FN3 | 30 | 40 |
FN4 | 30 | 60 |
FN5 | 30 | 80 |
Table 6.
Pumping schedule for a single section.
Table 6.
Pumping schedule for a single section.
Construction Stage | Type of Liquid | Pumping Rate/ (m3/min) | Liquid Volume/m3 | Proppant Type | Proppant Concentration/(kg/m3) |
---|
pad fluid | Low viscosity slickwater | 6 | 230 | - | 0 |
Sand-carrying liquid | High viscosity slickwater | 6 | 150 | 30/50 low density ceramsite | 120 |
Sand-carrying liquid | High viscosity slickwater | 6 | 160 | 30/50 low density ceramsite | 140 |
Sand-carrying liquid | High viscosity slickwater | 6 | 160 | 30/50 low density ceramsite | 160 |
Sand-carrying liquid | High viscosity slickwater | 6 | 160 | 30/50 low density ceramsite | 200 |
Sand-carrying liquid | High viscosity slickwater | 6 | 160 | 30/50 low density ceramsite | 240 |
Sand-carrying liquid | High viscosity slickwater | 6 | 180 | 30/50 low density ceramsite | 280 |
Table 7.
Ratio of retained fluid volume to total fracturing fluid volume.
Table 7.
Ratio of retained fluid volume to total fracturing fluid volume.
Retained Fluid Volume/Total Fracturing Fluid Volume/(%) | Retained Fluid Volume/m3 |
---|
10 | 1200 |
20 | 2400 |
30 | 3600 |
40 | 4800 |
50 | 6000 |
60 | 7200 |
70 | 8400 |
80 | 9600 |
90 | 10,800 |