Features of Logging While Drilling in Horizontal Wells to Estimate Reservoir Properties

2019 ◽  
pp. 45-57
Author(s):  
M.A. Srebrodolskaya ◽  
Keyword(s):  
Horizontal Wells ◽  
Reservoir Properties ◽  
Logging While Drilling

Revealing Hidden Information: High-Resolution Logging-While-Drilling Slowness Measurements and Imaging Using Advanced Dual Ultrasonic Technology

2021 ◽  
Vol 62 (1) ◽  
pp. 89-108
Author(s):  
Matthew Blyth ◽  
◽  
Naoki Sakiyama ◽  
Hiroshi Hori ◽  
Hiroaki Yamamoto ◽  
...  
Keyword(s):  
High Resolution ◽  
Elastic Wave ◽  
Horizontal Wells ◽  
Wellbore Stability ◽  
Frequency Range ◽  
Ultrasonic Technology ◽  
Logging While Drilling ◽  
Pulse Echo ◽  
Depth Of Investigation ◽  
Wave Properties

A new logging-while-drilling (LWD) acoustic tool has been developed with novel ultrasonic pitch-catch and pulse-echo technologies. The tool enables both high-resolution slowness and reflectivity images, which cannot be addressed with conventional acoustic logging. Measuring formation elastic-wave properties in complex, finely layered formations is routinely attempted with sonic tools that measure slowness over a receiver array with a length of 2 ft or more depending upon the tool design. These apertures lead to processing results with similar vertical resolutions, obscuring the true slowness of any layering occurring at a finer scale. If any of these layers present significantly different elastic-wave properties than the surrounding rock, then they can play a major role in both wellbore stability and hydraulic fracturing but can be absent from geomechanical models built on routine sonic measurements. Conventional sonic tools operate in the 0.1- to 20-kHz frequency range and can deliver slowness information with approximately 1 ft or more depth of investigation. This is sufficient to investigate the far-field slowness values but makes it very challenging to evaluate the near-wellbore region where tectonic stress redistribution causes pronounced azimuthal slowness variation. This stress-induced slowness variation is important because it is also a key driver of wellbore geomechanics. Moreover, in the presence of highly laminated formations, there can be a significant azimuthal variation of slowness due to layering that is often beyond the resolution of conventional sonic tools due to their operating frequency. Finally, in horizontal wells, multiple layer slownesses are being measured simultaneously because of the depth of investigation of conventional sonic tools. This can cause significant interpretational challenges. To address these challenges, an entirely new design approach was needed. The novel pitch-catch technology operates over a wide frequency range centered at 250 kHz and contains an array of receivers having a 2-in. receiver aperture. The use of dual ultrasonic technology allows the measurement of high-resolution slowness data azimuthally as well as reflectivity and caliper images. The new LWD tool was run in both vertical and horizontal wells and directly compared with both wireline sonic and imaging tools. The inch-scale slownesses obtained show characteristic features that clearly correlate to the formation lithology and structure indicated by the images. These features are completely absent from the conventional sonic data due to its comparatively lower vertical resolution. Slowness images from the tool reflect the formation elastic-wave properties at a fine scale and show dips and lithological variations that are complementary to the data from the pulse-echo images. The physics of the measurement are discussed, along with its ability to measure near-wellbore slowness, elastic-wave properties, and stress variations. Additionally, the effect of the stress-induced, near-wellbore features seen in the slowness images and the pulse-echo images is discussed with the wireline dipole shear anisotropy processing.

scholarly journals THE ANALYSIS OF METHODS OF RESERVOIR POROSITY-PERMEABILITY PROPERTIES STUDY IN HORIZONTAL WELLS TO ESTIMATE THE BOTTOM-HOLE TREATMENT RESULTS

2016 ◽  
pp. 72-77
Author(s):  
I. I. Mannanov ◽  
L. I. Garipova
Keyword(s):  
Horizontal Wells ◽  
Practical Application ◽  
Treatment Results ◽  
Reservoir Properties ◽  
Bottom Hole ◽  
Reservoir Porosity ◽  
Analysis Of Dynamics

Obtaining of the information about reservoir properties of formations is the basis of designing and the results analysis of production stimulation methods. Now two directions have been widely studied and applied, i.e. the hydrodynamic studies implementation using the method of the level recovery and the prolong analysis of dynamics of well producing characteristics. The paper discusses the practical application of both approaches for estimation of the need in treatment and the results of production intensification methods.

scholarly journals Numerical simulation and dimension reduction analysis of electromagnetic logging while drilling of horizontal wells in complex structures

2020 ◽  
Vol 17 (3) ◽  
pp. 645-657
Author(s):  
Zhen-Guan Wu ◽  
Shao-Gui Deng ◽  
Xu-Quan He ◽  
Runren Zhang ◽  
Yi-Ren Fan ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Dimension Reduction ◽  
Horizontal Wells ◽  
Complex Structures ◽  
Logging While Drilling

FORMATION EVALUATION AND STATIC MODELLING IN THE WHEATSTONE GAS FIELD

2006 ◽  
Vol 46 (1) ◽  
pp. 161 ◽  
Author(s):  
P. Theologou ◽  
M. Whelan
Keyword(s):  
Experimental Design ◽  
Early Stage ◽  
Potential Range ◽  
Reservoir Properties ◽  
Gas Field ◽  
Formation Evaluation ◽  
Place Assimilation ◽  
Logging While Drilling ◽  
Realistic Information ◽  
The Impact

The Wheatstone gas discovery is located about 110 km north-northwest of Barrow Island in the Dampier Subbasin, northwest Australia. Gas was intersected within the AA sands of the Mungaroo Formation, and within a thin overlying Tithonian sand. Core was acquired through the base of the Tithonian sand and the upper section of the Mungaroo Formation.A combination of logging while drilling, wireline logging, core acquisition and special core analysis has formed the basis of an extensive formation evaluation program for Wheatstone–1. The acquisition of this dataset, and associated interpretation, has allowed Chevron to maximise its ability to characterise the reservoir early in the field’s history, and thereby has helped our understanding of the uncertainties associated with the formation evaluation and geological modelling of this fluvial system. Petrological studies indicate that reservoir properties and mineralogy are strongly correlated with the mean grain size of the formation. The mineralogy of the sands is relatively simple with minor quartz overgrowth, K-feldspar dissolution and kaolinite precipitation being the dominant diagenetic events. The better quality sands are generally devoid of significant amounts of clays such as illite-smectite. Within the Tithonian sand, more exotic mineral suites are present including glauconitic and phosphatic minerals.A comparison of resistivity data from wireline and logging while drilling (LWD) across cored and non-cored intervals through the Mungaroo Formation has revealed the impact that slow coring has had on formation filtrate invasion. It has been interpreted that the combination of slow rate of penetration, non-optimised mud properties, and coring assembly design resulted in deep invasion through cored intervals. Deep resistivity response through the invaded formation was subdued, and initially resulted in an underestimation of reserves. The incorporation of saturation information from capillary pressure data has provided for a more realistic view of gas-in-place.In this early stage of field appraisal, the generation of representative and fit-for-purpose reservoir models is somewhat difficult due to the small amount of available data existing away from the well. To provide realistic information on the potential range of gas-in-place for the field, experimental design methodology was incorporated into the modelling work-flow. Experimental design allows for rapid and comprehensive modelling of the possible range of the dependant variables, in this case GIIP (gas initially in place). Assimilation of geological analogues, formation evaluation and their inherent uncertainties has attempted to capture the range of GIIP in this world-class gas discovery.

scholarly journals Rapid assessment of perfect time for transferring wells to water injection for pressure maintenance in low-permeable sediments of Tyumen suite of LLC «RN-Uvatneftegas» oilfields

2021 ◽  
Vol 931 (1) ◽  
pp. 012003
Author(s):  
B S Shevchenko ◽  
R R Ziazev
Keyword(s):  
Rapid Assessment ◽  
Water Injection ◽  
Horizontal Wells ◽  
Analytical Tool ◽  
Reservoir Properties ◽  
Injection Wells ◽  
Permeable Sediments ◽  
Maintenance System ◽  
Reservoir Development ◽  
Organization Strategy

Abstract A significant part of the initial geological reserves of LLC “RN-Uvatneftegas” oilfields are concentrated in deposits with abnormally low reservoir properties (porosity, permeability). The organization strategy of pressure maintenance of such oilfields significantly affect to the economic profitability of the reservoir development. One of the major tasks to achieve this goal is to determine the perfect time for application injection wells in oil production before forming the pressure maintenance system. Often, the solution to this issue turns out to be labor-intensive. In this regard, the analytical tool has been developed that allows rapidly assess the perfect time for transferring wells to water injection for pressure maintenance forming. The developed tool is based on a statistical analysis of the decline rate of horizontal wells fluid rates at the RN-Uvatneftegas oilfields. And also a comparative analysis of the results of the developed tool and other existing methods was carried out. The analysis showed that the developed tool is distinguished by its accuracy, simplicity and efficiency of work.

IMPROVING RECOVERY IN A THIN OIL COLUMN RESERVOIR—TUNA M–1 RESERVOIR EXPERIENCE IN THE GIPPSLAND BASIN, SOUTHEAST AUSTRALIA

2003 ◽  
Vol 43 (1) ◽  
pp. 175
Author(s):  
C. Santamaria ◽  
R. Fish
Keyword(s):  
Horizontal Well ◽  
Pressure Support ◽  
Horizontal Wells ◽  
Surveillance Data ◽  
Reservoir Properties ◽  
Actual Performance ◽  
New West ◽  
Expected Performance ◽  
Oil Rim ◽  
Gippsland Basin

The Tuna M–1 reservoir was developed in 1997 from both the new West Tuna platform and the existing Tuna A platform in the Gippsland Basin. The M–1 reservoir is contained within an anticlinal closure with an approximate gross hydrocarbon column of 85 metres. The oil column was originally 12 m thick and is supported by a large gas cap and a strong flank aquifer.Performance from the M–1 reservoir has been good, due to excellent reservoir properties. The combination of conventional and geo-steered horizontal wells has performed well with recovery efficiencies of 70% observed in many parts of the field. Lower than expected performance from the northwestern edge of the oil rim was, however, a significant anomaly, with recovery efficiencies 10% lower than from comparable rock in the southern and eastern parts of the field. The underlying cause of this lower performance was believed to be the result of an anisotropic aquifer response allowing greater pressure support along the northwestern flank of the fieldA re-entry well was drilled from a watered out horizontal well on the Tuna A platform in December 2000. This well was drilled as an oil production opportunity and as a key surveillance data point for the northwestern flank of the field. Results led to further surveillance including contact monitoring and production logging in horizontal wells. In addition to this, simulations were updated to reflect actual performance and surveillance data. Subsequent analysis supported development of a work program for new M–1 drainage points, including additional drill wells and the conversion of existing, watered out horizontal wells to conventional wells. The M–1 redevelopment work has been highly successful with production rates increasing by about 20,000 barrels per day in the first nine months of the program.

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