Crosswell monitoring using virtual sources and horizontal wells

Geophysics ◽  
2010 ◽  
Vol 75 (3) ◽  
pp. SA37-SA43 ◽  
Author(s):  
Joongmoo Byun ◽  
Jeongmin Yu ◽  
Soon Jee Seol
Keyword(s):  
Heavy Oil ◽  
Synthetic Data ◽  
Horizontal Wells ◽  
Time Lapse ◽  
Potential Change ◽  
New Method ◽  
Virtual Source ◽  
Vertical Wells ◽  
Monitoring Method ◽  
First Arrival

Time-lapse crosswell seismic provides an efficient way to monitor the migration of a [Formula: see text] plume or its leakage after [Formula: see text] injection into a geologic formation. Recently, crosswell seismic has become a powerful tool for monitoring underground variations, using the concept of a virtual source, with virtual sources positioned at the receivers installed in the well and thus the positions of sources and receivers can be invariant during monitoring. However, time-lapse crosswell seismic using vertical wells and virtual sources has difficulty in describing the front of a [Formula: see text] plume, which usually is parallel to the vertical wells, and in obtaining sufficient ray coverage for the first-arrival tomography. These problems arise because of the theoretical downward-illumination-directivity limitation of the virtual source. We have developed an effective monitoring method that uses virtual sources and two horizontal wells: one above and one below the [Formula: see text]sequestration reservoir. In our method, we redatum the traces that are recorded at geophones in horizontal wells from sources on the surface. The redatumed traces then become virtual traces recorded at geophones in the lower well and sent from virtual sources at the positions of the geophones in the upper well. The geometry of our method has advantages for locating the front of the [Formula: see text] plume, which is normal to the horizontal wells, compared with either real or virtual sources. The method also is advantageous in acquiring full ray coverage between the wells, and that coverage is superior to coverage acquired using vertical crosswell seismic with virtual sources. In addition, we can avoid problems related to any potential change in the medium above the reservoir and in the source and receiver positions. The results of applying our method to synthetic data that simulate [Formula: see text]-sequestration monitoring show that the front of a [Formula: see text] plume in the reservoir is depicted accurately in a velocity tomogram. The new method also can be used to monitor a reservoir during production of heavy oil.

A Study to Prevent Bottom Water From Coning in Heavy-Oil Reservoirs: Design and Simulation Approaches

2008 ◽  
Vol 130 (3) ◽  
Author(s):  
Binshan Ju ◽  
Xiaofeng Qiu ◽  
Shugao Dai ◽  
Tailiang Fan ◽  
Haiqing Wu ◽  
...  
Keyword(s):  
Heavy Oil ◽  
Bottom Water ◽  
Horizontal Wells ◽  
Oil Well ◽  
Vertical Wells ◽  
Water Contact ◽  
Water Columns ◽  
Heavy Oil Reservoirs ◽  
Oil Water ◽  
Downhole Water Sink

The coning problems for vertical wells and the ridging problems for horizontal wells are very difficult to solve by conventional methods during oil production from reservoirs with bottom water drives. If oil in a reservoir is too heavy to follow Darcy’s law, the problems may become more complicated for the non-Newtonian properties of heavy oil and its rheology. To solve these problems, an innovative completion design with downhole water sink was presented by dual-completion in oil and water columns with a packer separating the two completions for vertical wells or dual-horizontal wells. The design made it feasible that oil is produced from the formation above the oil water contact (OWC) and water is produced from the formation below the OWC, respectively. To predict quantitatively the production performances of production well using the completion design, a new improved mathematical model considering non-Newtonian properties of oil was presented and a numerical simulator was developed. A series of runs of an oil well was employed to find out the best perforation segment and the fittest production rates from the formations above and below OWC. The study shows that the design is effective for heavy oil reservoir with bottom water though it cannot completely eliminate the water cone formed before using the design. It is a discovery that the design is more favorable for new wells and the best perforation site for water sink (Sink 2) is located at the upper 1/3 of the formation below OWC.

Correcting source and receiver scaling for virtual source imaging and monitoring

Geophysics ◽  
2018 ◽  
Vol 83 (3) ◽  
pp. Q15-Q24 ◽  
Author(s):  
Andrey Bakulin ◽  
Dmitry Alexandrov ◽  
Christos Saragiotis ◽  
Abdullah Al Ramadan ◽  
Boris Kashtan
Keyword(s):  
Synthetic Data ◽  
Time Lapse ◽  
Destructive Interference ◽  
Virtual Source ◽  
Source Imaging ◽  
Data Set ◽  
Subsurface Geology ◽  
Monitoring Applications ◽  
Source Signal ◽  
Amplitude Level

Virtual source redatuming is a data-driven interferometric approach that relies on constructive and destructive interference, and as a result it is quite sensitive to input seismic trace amplitudes. Land surveys are prone to amplitude changes that are unrelated to subsurface geology (source/receiver coupling, etc.). We have determined that such variations may be particularly damaging to construct a virtual-source signal for imaging and seismic monitoring applications, and they need to be correctly compensated before satisfactory images, repeatability, and proper relative amplitudes are achieved. We examine two methods to correct for these variations: a redatuming approach based on multidimensional deconvolution and multisurvey surface-consistent (SC) scaling. Using synthetic data, we discover that the first approach can only balance time-dependent variations between repeat surveys, e.g., compensate for variable shot scaling. In contrast, a multisurvey SC approach can compensate for shot and receiver scaling within each survey and among the surveys. As a result, it eliminates redatuming artifacts, brings repeat surveys to a common amplitude level, while preserving relative amplitudes required for quantitative interpretation of 4D amplitude differences. Applying an SC approach to a land time-lapse field data set with buried receivers from Saudi Arabia, we additionally conclude that separate SC scaling of early arrivals and deep reflections may produce better image and repeatability. This is likely due to the significantly different frequency content of early arrivals and deep reflections.

New Method of Steam Channeling Plugging in Horizontal Wells of Heavy Oil Steam Stimulation

2016 ◽  
Author(s):  
Haiyang Yu ◽  
Liangchuan Li ◽  
Jiapeng Zheng ◽  
Wenjuan Ji ◽  
Xiaoping Qin ◽  
...  
Keyword(s):  
Heavy Oil ◽  
Horizontal Wells ◽  
New Method ◽  
Steam Stimulation

scholarly journals Visual4DTracker: a tool to interact with 3D + t image stacks

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Ermanno Cordelli ◽  
Paolo Soda ◽  
Giulio Iannello
Keyword(s):  
Synthetic Data ◽  
Time Lapse ◽  
Temporal Data ◽  
Image Stack ◽  
Biological Phenomena ◽  
Insulin Granules ◽  
Matlab Package ◽  
User Friendly ◽  
Drosophila Cells ◽  
Over Time

Abstract Background Biological phenomena usually evolves over time and recent advances in high-throughput microscopy have made possible to collect multiple 3D images over time, generating $$3D+t$$ 3 D + t (or 4D) datasets. To extract useful information there is the need to extract spatial and temporal data on the particles that are in the images, but particle tracking and feature extraction need some kind of assistance. Results This manuscript introduces our new freely downloadable toolbox, the Visual4DTracker. It is a MATLAB package implementing several useful functionalities to navigate, analyse and proof-read the track of each particle detected in any $$3D+t$$ 3 D + t stack. Furthermore, it allows users to proof-read and to evaluate the traces with respect to a given gold standard. The Visual4DTracker toolbox permits the users to visualize and save all the generated results through a user-friendly graphical user interface. This tool has been successfully used in three applicative examples. The first processes synthetic data to show all the software functionalities. The second shows how to process a 4D image stack showing the time-lapse growth of Drosophila cells in an embryo. The third example presents the quantitative analysis of insulin granules in living beta-cells, showing that such particles have two main dynamics that coexist inside the cells. Conclusions Visual4DTracker is a software package for MATLAB to visualize, handle and manually track $$3D+t$$ 3 D + t stacks of microscopy images containing objects such cells, granules, etc.. With its unique set of functions, it remarkably permits the user to analyze and proof-read 4D data in a friendly 3D fashion. The tool is freely available at https://drive.google.com/drive/folders/19AEn0TqP-2B8Z10kOavEAopTUxsKUV73?usp=sharing

scholarly journals Reconstruction scheme for excitatory and inhibitory dynamics with quenched disorder: application to zebrafish imaging

2021 ◽  
Author(s):  
Lorenzo Chicchi ◽  
Gloria Cecchini ◽  
Ihusan Adam ◽  
Giuseppe de Vito ◽  
Roberto Livi ◽  
...  
Keyword(s):  
Structural Information ◽  
Activity Patterns ◽  
Synthetic Data ◽  
Light Sheet ◽  
Time Lapse ◽  
Inhibitory Neurons ◽  
Mean Field Approximation ◽  
Directed Network ◽  
Dynamical Regime ◽  
Power Law Distribution

AbstractAn inverse procedure is developed and tested to recover functional and structural information from global signals of brains activity. The method assumes a leaky-integrate and fire model with excitatory and inhibitory neurons, coupled via a directed network. Neurons are endowed with a heterogenous current value, which sets their associated dynamical regime. By making use of a heterogenous mean-field approximation, the method seeks to reconstructing from global activity patterns the distribution of in-coming degrees, for both excitatory and inhibitory neurons, as well as the distribution of the assigned currents. The proposed inverse scheme is first validated against synthetic data. Then, time-lapse acquisitions of a zebrafish larva recorded with a two-photon light sheet microscope are used as an input to the reconstruction algorithm. A power law distribution of the in-coming connectivity of the excitatory neurons is found. Local degree distributions are also computed by segmenting the whole brain in sub-regions traced from annotated atlas.

A New Method for Designing 3D Trajectory in Sidetracking Horizontal Wells Under Multi-constraints

1999 ◽  
Author(s):  
Jiang Shengzong ◽  
Wang Xilu ◽  
Cao Limin ◽  
Liu Kunfang
Keyword(s):  
Horizontal Wells ◽  
New Method

Stochastic inversion of pressure and saturation changes from time-lapse AVO data

Geophysics ◽  
2006 ◽  
Vol 71 (5) ◽  
pp. C81-C92 ◽  
Author(s):  
Helene Hafslund Veire ◽  
Hilde Grude Borgos ◽  
Martin Landrø
Keyword(s):  
Stochastic Model ◽  
Seismic Data ◽  
Synthetic Data ◽  
Time Lapse ◽  
Bayesian Framework ◽  
Reservoir Modeling ◽  
Data Set ◽  
The North ◽  
Fluid Saturation ◽  
Likelihood Model

Effects of pressure and fluid saturation can have the same degree of impact on seismic amplitudes and differential traveltimes in the reservoir interval; thus, they are often inseparable by analysis of a single stacked seismic data set. In such cases, time-lapse AVO analysis offers an opportunity to discriminate between the two effects. We quantify the uncertainty in estimations to utilize information about pressure- and saturation-related changes in reservoir modeling and simulation. One way of analyzing uncertainties is to formulate the problem in a Bayesian framework. Here, the solution of the problem will be represented by a probability density function (PDF), providing estimations of uncertainties as well as direct estimations of the properties. A stochastic model for estimation of pressure and saturation changes from time-lapse seismic AVO data is investigated within a Bayesian framework. Well-known rock physical relationships are used to set up a prior stochastic model. PP reflection coefficient differences are used to establish a likelihood model for linking reservoir variables and time-lapse seismic data. The methodology incorporates correlation between different variables of the model as well as spatial dependencies for each of the variables. In addition, information about possible bottlenecks causing large uncertainties in the estimations can be identified through sensitivity analysis of the system. The method has been tested on 1D synthetic data and on field time-lapse seismic AVO data from the Gullfaks Field in the North Sea.

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