Testing of a Permanent Orbital Surface Source and Distributed Acoustic Sensing for monitoring of unconventional reservoirs: preliminary results from the Eagle Ford Shale

Geophysics ◽  
2020 ◽  
pp. 1-42
Author(s):  
Feng Cheng ◽  
Julia Correa ◽  
Shan Dou ◽  
Barry Freifeld ◽  
Todd Wood ◽  
...  
Keyword(s):  
High Resolution ◽  
Horizontal Well ◽  
Low Cost ◽  
Time Lapse ◽  
Unconventional Reservoirs ◽  
S Wave ◽  
Eagle Ford ◽  
Preliminary Results ◽  
Distributed Acoustic Sensing ◽  
High Repeatability

The effective monitoring of hydraulic fracturing in unconventional oil and gas production requires tools to quantify elastic property variations even in the absence of microseismic activity. To track the subtle time-lapse variations in reservoir properties during such activities, monitoring techniques with high repeatability and high resolution, both spatially and temporally, are required. Distributed Acoustic Sensing (DAS) is a rapidly maturing fiber-optic technology for low-cost, permanent, high density in-well monitoring. Surface Orbital Vibrators (SOVs) are an inexpensive fixed rotary seismic sources that offer the opportunity to frequently interrogate the subsurface with energies comparable to vibroseis sources. We present a field VSP test, conducted in the Eagle Ford play, pairing an SOV source recorded by DAS behind casing in a deviated well to better evaluate the potential of the technology set for unconventional reservoir monitoring. We demonstrate the data processing workflow for reservoir monitoring using SOV-DAS system. We analyze the data characteristics of SOV-DAS system, including S/N (signal to noise ratio) characteristics and source repeatability. High-quality P- and S- wave reflections, as well as mode conversions, are visible in the vertical section. In addition, clear P-P reflections are also observable along the horizontal well sections. Time-shifts with a mean value 10 μs between different datasets demonstrate the high repeatability for the semi-permanent SOV source, which is crucial for time-lapse analysis. We also apply reflection imaging on both P- and S- to reveal reflection depths. In a first-of-its-kind deployment, we implemented a rotating SOV with a slewing bearing and discuss the possibility to optimize S-wave construction along the horizontal well with specific SOV orientation directions. Our preliminary results show that the combination of repeatable surface sources such as SOVs with DAS has significant potential for providing a low-cost approach for high resolution seismic monitoring of unconventional reservoirs.

A time-lapse seismic repeatability test using the P-Cable high-resolution 3D marine acquisition system

2020 ◽  
Vol 39 (7) ◽  
pp. 480-487
Author(s):  
Patrick Smith ◽  
Brandon Mattox
Keyword(s):  
High Resolution ◽  
Seismic Data ◽  
Low Cost ◽  
Low Frequency ◽  
Time Lapse ◽  
Seismic Signal ◽  
Residual Energy ◽  
Acquisition System ◽  
Positioning Errors ◽  
Seismic Surveying

The P-Cable high-resolution 3D marine acquisition system tows many short, closely separated streamers behind a small source. It can provide 3D seismic data of very high temporal and spatial resolution. Since the system is containerized and has small dimensions, it can be deployed at short notice and relatively low cost, making it attractive for time-lapse seismic reservoir monitoring. During acquisition of a 3D high-resolution survey in the Gulf of Mexico in 2014, a pair of sail lines were repeated to form a time-lapse seismic test. We processed these in 2019 to evaluate their geometric and seismic repeatability. Geometric repetition accuracy was excellent, with source repositioning errors below 10 m and bin-based receiver positioning errors below 6.25 m. Seismic data comparisons showed normalized root-mean-square difference values below 10% between 40 and 150 Hz. Refinements to the acquisition system since 2014 are expected to further improve repeatability of the low-frequency components. Residual energy on 4D difference seismic data was low, and timing stability was good. We conclude that the acquisition system is well suited to time-lapse seismic surveying in areas where the reservoir and time-lapse seismic signal can be adequately imaged by small-source, short-offset, low-fold data.

Frequent 4D monitoring with DAS 3D VSP in deep water to reveal injected water-sweep dynamics

2020 ◽  
Vol 39 (7) ◽  
pp. 471-479 ◽  
Author(s):  
Denis Kiyashchenko ◽  
Albena Mateeva ◽  
Yuting Duan ◽  
Duane Johnson ◽  
Jonathan Pugh ◽  
...  
Keyword(s):  
Deep Water ◽  
Low Cost ◽  
Water Injection ◽  
Time Lapse ◽  
Reservoir Model ◽  
Seismic Profiles ◽  
Vertical Seismic Profiles ◽  
Distributed Acoustic Sensing ◽  
The Impact

Time-lapse monitoring using 3D distributed acoustic sensing vertical seismic profiles (DAS VSPs) is rapidly maturing as a nonintrusive low-cost solution for target-oriented monitoring in deep water. In a Gulf of Mexico field, DAS fibers deployed in active wells enable detailed tracking of the water flood in two deep reservoirs. Multiple tests in adverse well conditions let us understand the impact of source size and other factors on the spatially dependent quality of time-lapse DAS data and prove that excellent image repeatability is achievable under typical field conditions. Frequent repeat surveys allowed us to predict the timing of water arrival in a producer and to observe new water injection patterns that are important for understanding water-flood performance. Going forward, DAS 4D monitoring is envisioned as a tool that can assist with proactive wells and reservoir management, new well planning, and reservoir model updates.

Estimation of rock frame weakening using time-lapse crosswell: The Frio brine pilot project

Geophysics ◽  
2016 ◽  
Vol 81 (6) ◽  
pp. B235-B245 ◽  
Author(s):  
Mohammed Al Hosni ◽  
Stéphanie Vialle ◽  
Boris Gurevich ◽  
Thomas M. Daley
Keyword(s):  
High Resolution ◽  
Rock Physics ◽  
Pilot Project ◽  
Time Lapse ◽  
Analysis Method ◽  
Resolution Time ◽  
S Wave ◽  
Geomechanical Properties ◽  
Before And After ◽  
Rock Microstructure

[Formula: see text] injection into subsurface reservoirs leads to pressure and saturation changes. Furthermore, [Formula: see text]-brine-minerals interaction could result in dissolution or reprecipitation of rock frame-forming minerals. Observed time-lapse seismic associated with [Formula: see text] injection into poorly consolidated sandstone at the Frio [Formula: see text] injection site (Texas, USA) could not be predicted using classical rock-physics models (i.e., models involving elastic changes in the rock frame due to saturations and/or pressures changes only, and assuming no changes in the rock microstructure). That, and the changes in the fluid chemistry after [Formula: see text] injection, suggests that the assumption of a constant rock microstructure might be violated. Using high-resolution time-lapse crosswell data, we have developed a methodology for estimating changes in the rock frame by quantifying the rock-frame drained moduli before and after [Formula: see text] injection. Based on rock microstructure diagnostics, we found that the changes in the drained frame elastic properties are due to the changes in the grain contact-cement percentage. The reduction in contact-cement percent is found to be variable throughout the reservoir, with a maximum near the injection well, down to 0.01% from the initial 0.1% contact cement; this results in more than 40% reduction in the drained frame shear and bulk moduli. [Formula: see text] saturation was estimated using this model for uniform and patchy saturation cases. Our rock-physics analysis may allow improved interpretation of time-lapse seismic for [Formula: see text] saturation in the context of other poorly consolidated sandstones with similar geomechanical properties. Having the P- and S-wave velocity time-lapse data is key to improve saturation estimates with this analysis method.

scholarly journals A Novel Low-Cost, High-Resolution Camera System for Measuring Peat Subsidence and Water Table Dynamics

2021 ◽  
Vol 9 ◽  
Author(s):  
Chris D. Evans ◽  
Nathan Callaghan ◽  
Adi Jaya ◽  
Alistair Grinham ◽  
Sofie Sjogersten ◽  
...  
Keyword(s):  
High Resolution ◽  
Water Table ◽  
Large Scale ◽  
Low Cost ◽  
Ghg Emissions ◽  
Time Lapse ◽  
Surface Elevation ◽  
Carbon Loss ◽  
Camera System ◽  
Peat Surface

Peatlands are highly dynamic systems, able to accumulate carbon over millennia under natural conditions, but susceptible to rapid subsidence and carbon loss when drained. Short-term, seasonal and long-term peat surface elevation changes are closely linked to key peatland attributes such as water table depth (WTD) and carbon balance, and may be measured remotely using satellite radar and LiDAR methods. However, field measurements of peat elevation change are spatially and temporally sparse, reliant on low-resolution manual subsidence pole measurements, or expensive sensor systems. Here we describe a novel, simple and low-cost image-based method for measuring peat surface motion and WTD using commercially available time-lapse cameras and image processing methods. Based on almost two years’ deployment of peat cameras across contrasting forested, burned, agricultural and oil palm plantation sites in Central Kalimantan, Indonesia, we show that the method can capture extremely high resolution (sub-mm) and high-frequency (sub-daily) changes in peat surface elevation over extended periods and under challenging environmental conditions. WTD measurements were of similar quality to commercially available pressure transducers. Results reveal dynamic peat elevation response to individual rain events, consistent with variations in WTD. Over the course of the relatively severe 2019 dry season, cameras in deep-drained peatlands recorded maximum peat shrinkage of over 8 cm, followed by partial rebound, leading to net annual subsidence of up to 5 cm. Sites with higher water tables, and where borehole irrigation was used to maintain soil moisture, had lower subsidence, suggesting potential to reduce subsidence through altered land-management. Given the established link between subsidence and CO2 emissions, these results have direct implications for the management of peatlands to reduce high current greenhouse gas (GHG) emissions. Camera-based sensors provide a simple, low-cost alternative to commercial elevation, WTD and GHG flux monitoring systems, suitable for deployment at scale, and in areas where existing approaches are impractical or unaffordable. If ground-based observations of peat motion can be linked to measured GHG fluxes and with satellite-based monitoring tools, this approach offers the potential for a large-scale peatland monitoring tool, suitable for identifying areas of active carbon loss, targeting climate change mitigation interventions, and evaluating intervention outcomes.

Modeling the seismic response of individual hydraulic fracturing stages observed in a time-lapse distributed acoustic sensing vertical seismic profiling survey

Geophysics ◽  
2020 ◽  
Vol 85 (4) ◽  
pp. T225-T235
Author(s):  
Gary Binder ◽  
Aleksei Titov ◽  
Youfang Liu ◽  
James Simmons ◽  
Ali Tura ◽  
...  
Keyword(s):  
Hydraulic Fracturing ◽  
Decay Time ◽  
Time Lapse ◽  
S Wave ◽  
Acoustic Sensing ◽  
Seismic Profiling ◽  
Vertical Seismic Profiling ◽  
Effective Medium Model ◽  
Surface Time ◽  
Distributed Acoustic Sensing

In 2017, distributed acoustic sensing (DAS) technology was deployed in a horizontal well to conduct a vertical seismic profiling survey before and after each of 78 hydraulic fracturing stages. From two vibroseis source locations at the surface, time shifts of P- and S-waves were observed but decayed over days. Some stages also showed waves scattered off the stimulated rock volume. We have used 2D finite difference elastic wavefield modeling to understand these observations and connect them to underlying properties of the stimulated rock. We have developed an effective medium model of vertical fractures that close exponentially with time as fluid leaks off into the formation can match the distribution of P- and S-wave time shifts along the well. This has enabled estimates of the height, normal and tangential fracture compliance values, and decay time of the stimulated rock volume. Additionally, the kinematics of scattered waves observed in the data have been found to be consistent with PS conversion across the stimulated rock volume from an individual stage. With higher quality DAS data, stage-by-stage inversion for height, fracture compliance, and decay time attributes may be possible for characterizing variations in the effectiveness of hydraulic fracturing.

scholarly journals Extracting High Resolution Snow Distribution Information with Inexpensive Autonomous Cameras

10.29007/93gh ◽  
2018 ◽  
Author(s):  
Pauline Millet ◽  
Hendrik Huwald ◽  
Steven V. Weijs
Keyword(s):  
High Resolution ◽  
Low Cost ◽  
Time Lapse ◽  
Distortion Correction ◽  
Snow Covered Area ◽  
Covered Area ◽  
Digital Elevation ◽  
Snow Distribution ◽  
Elevation Model ◽  
Time Lapse Photography

This study details a procedure to derive high resolution snow cover information using low-cost autonomous cameras. Images from time lapse photography of target areas are used to obtain temporally resolved binary snow-covered area information. Various image processing steps, such as distortion correction, alignment, projection using the Digital Elevation Model (DEM), and classification using clustering are described. Several innovations, such as matching the mountain silhouette with the DEM, and application of specific filters are described to make this terrestrial remote sensing method generally applicable to derive valuable snow information.

Signature of Transpressional Tectonics in the Holocene Stratigraphy of Lake Azuei, Haiti: Preliminary Results From a High-Resolution Subbottom Profiling Survey

2018 ◽  
Author(s):  
Marie-Helene Cormier ◽  
Heather Sloan ◽  
Dominique Boisson ◽  
Britta Brown ◽  
Kelly Guerrier ◽  
...  
Keyword(s):  
High Resolution ◽  
The Holocene ◽  
Preliminary Results ◽  
Holocene Stratigraphy ◽  
Subbottom Profiling

scholarly journals A Framework for a New Approach to Empower Users Through Low-Cost and Do-It-Yourself Assistive Technology

2021 ◽  
Vol 18 (6) ◽  
pp. 3039
Author(s):  
Thais Pousada García ◽  
Jessica Garabal-Barbeira ◽  
Patricia Porto Trillo ◽  
Olalla Vilar Figueira ◽  
Cristina Novo Díaz ◽  
...  
Keyword(s):  
Assistive Technology ◽  
Outcome Measures ◽  
Design Thinking ◽  
Low Cost ◽  
Well Being ◽  
Pilot Project ◽  
Assistive Device ◽  
Preliminary Results ◽  
Do It Yourself ◽  
Principles Of Design

Background: Assistive Technology (AT) refers to “assistive products and related systems and services developed for people to maintain or improve functioning and thereby to promote well-being”. Improving the process of design and creation of assistive products is an important step towards strengthening AT provision. Purpose: (1) to present a framework for designing and creating Low-Cost AT; (2) to display the preliminary results and evidence derived from applying the framework. Methodology: First, an evidence-based process was applied to develop and conceptualize the framework. Then, a pilot project to validate the framework was carried out. The sample was formed by 11 people with disabilities. The measure instruments were specific questionnaire, several forms of the Matching Person-Technology model, the Psychosocial Impact of Assistive Device Scale, and a tool to assess the usability and universal design of AT. Results: The framework integrates three phases: Identification (Design), Creation (Making the prototype), and Implementation (Outcome Measures), based on the principles of Design Thinking, and with a user-centered perspective. The preliminary results showed the coherence of the entire process and its applicability. The matching between person and device was high, representing the importance of involving the user in the design and selection of AT. Conclusions: The framework is a guide for professionals and users to apply a Low-Cost and Do-It-Yourself perspective to the provision of AT. It highlights the importance of monitoring the entire procedure and measuring the effects, by applying the outcome measures.

scholarly journals Fabrication and Compressive Behavior of a Micro-Lattice Composite by High Resolution DLP Stereolithography

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 785
Author(s):  
Chow Shing Shin ◽  
Yu Chia Chang
Keyword(s):  
High Resolution ◽  
Lattice Structure ◽  
Low Cost ◽  
Hierarchical Structures ◽  
Dip Coating ◽  
Unit Cell ◽  
Digital Light Processing ◽  
Unit Cell Size ◽  
Wide Range ◽  
And Performance

Lattice structures are superior to stochastic foams in mechanical properties and are finding increasing applications. Their properties can be tailored in a wide range through adjusting the design and dimensions of the unit cell, changing the constituent materials as well as forming into hierarchical structures. In order to achieve more levels of hierarchy, the dimensions of the fundamental lattice have to be small enough. Although lattice size of several microns can be fabricated using the two-photon polymerization technique, sophisticated and costly equipment is required. To balance cost and performance, a low-cost high resolution micro-stereolithographic system has been developed in this work based on a commercial digital light processing (DLP) projector. Unit cell lengths as small as 100 μm have been successfully fabricated. Decreasing the unit cell size from 150 to 100 μm increased the compressive stiffness by 26%. Different pretreatments to facilitate the electroless plating of nickel on the lattice structure have been attempted. A pretreatment of dip coating in a graphene suspension is the most successful and increased the strength and stiffness by 5.3 and 3.6 times, respectively. Even a very light and incomplete nickel plating in the interior has increase the structural stiffness and strength by more than twofold.

scholarly journals Development of single-cell-level microfluidic technology for long-term growth visualization of living cultures of Mycobacterium smegmatis

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Han Wang ◽  
Gloria M. Conover ◽  
Song-I Han ◽  
James C. Sacchettini ◽  
Arum Han
Keyword(s):  
Drug Treatment ◽  
Single Cell ◽  
Mycobacterium Smegmatis ◽  
Culture Media ◽  
Low Cost ◽  
Bacterial Pathogen ◽  
Growth Dynamics ◽  
Time Lapse ◽  
Cell Phenotype

AbstractAnalysis of growth and death kinetics at single-cell resolution is a key step in understanding the complexity of the nonreplicating growth phenotype of the bacterial pathogen Mycobacterium tuberculosis. Here, we developed a single-cell-resolution microfluidic mycobacterial culture device that allows time-lapse microscopy-based long-term phenotypic visualization of the live replication dynamics of mycobacteria. This technology was successfully applied to monitor the real-time growth dynamics of the fast-growing model strain Mycobacterium smegmatis (M. smegmatis) while subjected to drug treatment regimens during continuous culture for 48 h inside the microfluidic device. A clear morphological change leading to significant swelling at the poles of the bacterial membrane was observed during drug treatment. In addition, a small subpopulation of cells surviving treatment by frontline antibiotics was observed to recover and achieve robust replicative growth once regular culture media was provided, suggesting the possibility of identifying and isolating nonreplicative mycobacteria. This device is a simple, easy-to-use, and low-cost solution for studying the single-cell phenotype and growth dynamics of mycobacteria, especially during drug treatment.

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