This study examines which is the margin of usability for Artificial Intelligence (AI) algorithms related to the rock properties distribution in static modeling. This novel method shows a forward modeling approach using neural networks and genetic algorithms to optimize correlation patterns among seismic traces of stack volumes and well rock properties. Once a set of nonlinear functions is optimized in the well locations, to correlate seismic traces and rock properties, spatial response is estimated using the seismic volume. This seismic characterization process is directly dependent on the error minimization during the structural seismic interpretation process, as well as, honoring the structural complexity while modeling. Previous points are key elements to obtain an adequate correlation between well data and seismic traces. The joint mechanism of neural networks and genetic algorithms globally optimize the nonlinear functions and its parameters to minimize the cost function. Estimated objective function correlates well rock properties with seismic stack data. This mechanism is applied to real data, within a high structural complexity and several wells. As an output, calibrated petrophysical time volumes in the interval of interest are obtained. Properties are used initially to generate a geological facies model. Subsequently, facies and seismic properties are used for the three-dimensional distribution of petrophysical properties such as: rock type, porosity, clay volume and permeability. Therefore, artificial intelligence algorithms can be widely exploited for uncertainty reduction within the rock property spatial estimation.
Even though coring of rocks is the best way to characterize reservoir and source rocks geologically and petrophysically, this method is considered expensive, having a relatively high cost per foot. Alternatively, side-wall cores and cuttings are widely used in reservoir characterization at a relatively low cost. However, this method has limitations related to cuttings bad physical conditions, size, mixed lithological and mineralogical characteristics which make the commonly used conventional evaluation methods not applicable. This study introduces a robust combination of digital and conventional core analysis methods to overcome these limitations and characterize reservoir and shale cuttings derived from two hydrocarbon-bearing formations in New Zealand.
Initially, all cuttings from both formations were screened based on their cutting sizes and later based on the visually observed textures using the stereomicroscope. This helped in selecting representative cuttings for the main identified textures. These cuttings were CT imaged at a resolution ranging from 40 to 4 microns/voxel resolution in order to confirm their rock textures and sedimentary structures for better characterization results. Next, mercury injection capillary pressure (MICP), X-ray diffraction (XRD), and petrographical analysis were conducted on all selected cuttings with different rock textures in order to understand the pore types, textural variations, diagenetic overprints and mineralogy of the cuttings samples. Then, they were scanned at optimum resolutions using Micro CT and 3D FIB-SEM microscopies. Finally, all acquired images were segmented digitally and 3D rock volumes were created. These volumes were used in computing porosity, permeability, formation factor resistivity (FRF) and poroperm trends digitally using numerical simulation techniques.
Conventional and digital rock analysis showed that the cuttings derived from the reservoir interval are composed of an argillaceous sandstone with a very good computed porosity (18% up to 31%) and permeability (30 to 200 mD). On the other hand, the cuttings derived from the shale source rock interval, which were predominately composed of clay minerals, have a computed porosity of 12% to 13% (mainly inorganic pores) and an absolute permeability in the range of 0.5 to 4 Micro-Darcy. The digital poroperm trend analysis identified distinct poroperm trends for each formation which helped in understanding their petrophysical aspects.
This integration between conventional and digital methods provided better geological and petrophysical understanding of both formations using a limited number of cuttings, less cost and time.
This paper summarizes the benefits of using a bipolymer crosslinking system in environments where water quality cannot be guaranteed. It also demonstrates the yielded cost savings per well that are achievable when reusing 100% produced or flowback water for hydraulic fracturing. Analyzing the properties of produced water is a difficult process because of the extreme levels of suspended and dissolved particulates contained in it, and a chemistry profile that is in constant flux. In this study, samples of flowback water and downhole shales are analyzed to investigate the mechanisms controlling the chemistry of flowback water. This paper details the experience of using new stabilized crosslinked-fracturing-fluid systems in the Permian Basin using borated produced water.
Most shale producers in North America have given little thought to the flowback stage following hydraulic fracturing. Others have come to realize it represents a valuable opportunity to learn more about their wells. A rigorous modeling approach is developed for effective management and inventory analysis of natural-gas storage in underground salt caverns.
The effects of adding iron oxide NPs on the rheological and filtration properties of aqueous bentonite suspensions have been studied by several researchers. This paper presents an investigation into the effect of catalytic nanoparticles on the efficiency of recovery from continuous steam injection. A number of ongoing industry research projects are developing nanoparticles that work at the reservoir level and for fluid treatment. Though they may be a few years away from finalization, these efforts highlight nanotechnology’s increasingly sophisticated and growing application scope. This work focuses on the laboratory techniques for developing, assessing, and analyzing innovative water-based drilling fluids containing iron oxide (Fe2O3) and silica (SiO2) nanoparticles.
The technical challenges imposed by tight well spacing and fracture interactions have become a focal point of recent earnings calls between investors and the leaders of several shale producers. The picture of the future is becoming clearer, and there are fewer oil wells in it. A close look at hundreds of feet of fractured core samples suggest that new fracture models are needed to simulate complicated reality.
Make or Breakeven: Is Unconventional Oil Production Getting More Efficient? If the benchmark oil price is $10/bbl higher than the breakeven price for production that means companies are making good money, right? Maybe, but it’s hard to know what goes into a breakeven price. How can operators and service companies go forward in a shale-dominated industry with low oil prices? At the recent Leaders in Industry luncheon in Houston, Jonny Jones told the interesting story of how Jones Energy grew from a small private entity to a company whose shares trade on the New York Stock Exchange.
Some of the trends and issues related to water management for tight oil and gas are discussed, including environmental, sustainability, and legislative issues associated with water handling for hydraulic fracturing. Some of the trends and issues related to water management for tight oil and gas are discussed, including environmental, sustainability, and legislative issues associated with water handling for hydraulic fracturing.
UK's First Carbon Capture and Storage Project Could Be Operational by Mid-2020s The Acorn Project will capture about 200,000 tonnes of carbon dioxide from the St. Fergus Gas Terminal and transport it for storage to one of three depleted gas fields using existing pipelines. Levels of stress and mental health problems among UK workers are at a 17-year high, according to the latest injury and ill health statistics published by the Health and Safety Executive. The UK’s offshore oil and gas industry continued to see improvement across a broad range of health and safety indicators last year, according to a key insight published by Oil & Gas UK. Offshore Industry Has Come'Perilously Close to Disaster,' Warns UK's Health and Safety Executive The Health and Safety Executive (HSE) has warned the UK’s offshore oil and gas operators that they must do more to tackle hydrocarbon releases in the North Sea after coming “perilously close to disaster” in recent years. Oil & Gas UK recently published guidelines with its most up-to-date information aimed at helping operators ensure they have the required financial measurements in place to meet the cost of cleanup for an oil release. North Sea oil and gas production was up but greenhouse gas emissions in 2016 were down against 2015 performance, according to Oil & Gas UK’s Environment Report.