Monitoring geological storage of CO2: a new approach

AbstractGeological CO2 storage can be employed to reduce greenhouse gas emissions to the atmosphere. Depleted oil and gas reservoirs, deep saline aquifers, and coal beds are considered to be viable subsurface CO2 storage options. Remote monitoring is essential for observing CO2 plume migration and potential leak detection during and after injection. Leak detection is probably the main risk, though overall monitoring for the plume boundaries and verification of stored volumes are also necessary. There are many effective remote CO2 monitoring techniques with various benefits and limitations. We suggest a new approach using a combination of repeated seismic and electromagnetic surveys to delineate CO2 plume and estimate the gas saturation in a saline reservoir during the lifetime of a storage site. This study deals with the CO2 plume delineation and saturation estimation using a combination of seismic and electromagnetic or controlled-source electromagnetic (EM/CSEM) synthetic data. We assumed two scenarios over a period of 40 years; Case 1 was modeled assuming both seismic and EM repeated surveys were acquired, whereas, in Case 2, repeated EM surveys were taken with only before injection (baseline) 3D seismic data available. Our results show that monitoring the CO2 plume in terms of extent and saturation is possible both by (i) using a repeated seismic and electromagnetic, and (ii) using a baseline seismic in combination with repeated electromagnetic data. Due to the nature of the seismic and EM techniques, spatial coverage from the reservoir's base to the surface makes it possible to detect the CO2 plume’s lateral and vertical migration. However, the CSEM low resolution and depth uncertainties are some limitations that need consideration. These results also have implications for monitoring oil production—especially with water flooding, hydrocarbon exploration, and freshwater aquifer identification.

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Geological origins of seismic bright spot reflections in the Ordovician strata in the Halahatang area of the Tarim Basin, western China

Canadian Journal of Earth Sciences ◽

10.1139/cjes-2018-0055 ◽

2018 ◽

Vol 55 (12) ◽

pp. 1297-1311 ◽

Cited By ~ 2

Author(s):

Wei Yang ◽

Xiaoxing Gong ◽

Wenjie Li

Keyword(s):

Tarim Basin ◽

Oil And Gas ◽

High Amplitude ◽

Hydrothermal Activity ◽

Hydrocarbon Exploration ◽

Western China ◽

Bright Spot ◽

Gas Reservoirs ◽

Seismic Section ◽

Bright Spots

Anomalously high-amplitude seismic reflections are commonly observed in deeply buried Ordovician carbonate strata in the Halahatang area of the northern Tarim Basin. These bright spots have been demonstrated to be generally related to effective oil and gas reservoirs. These bright spot reflections have complex geological origins, because they are deeply buried and have been altered by multi-phase tectonic movement and karstification. Currently, there is no effective geological model for these bright spots to guide hydrocarbon exploration and development. Using core, well logs, and seismic data, the geological origins of bright spot are classified into three types, controlled by karstification, faulting, and volcanic hydrothermal activity. Bright spots differing by geological origin exhibit large differences in seismic reflection character, such as reflection amplitude, curvature, degree of distortion, and the number of vertically stacked bright spots in the seismic section. By categorizing the bright spots and the seismic character of the surrounding strata, their geological origins can after be inferred. Reservoirs formed by early karstification were later altered by epigenetic karstification. Two periods of paleodrainage further altered the early dissolution pores. In addition, faults formed by tectonic uplift also enhanced the dissolution of the flowing karst waters. Some reservoirs were subsequently altered by Permian volcanic hydrothermal fluids.

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SmartBall™: A New Approach in Pipeline Leak Detection

2008 7th International Pipeline Conference, Volume 2 ◽

10.1115/ipc2008-64065 ◽

2008 ◽

Cited By ~ 14

Author(s):

Richard Fletcher ◽

Muthu Chandrasekaran

Keyword(s):

Oil And Gas ◽

Public Awareness ◽

Detection Threshold ◽

Leak Detection ◽

Acoustic Sensor ◽

New Approach ◽

Loss And Damage ◽

Product Loss ◽

Awareness Programs ◽

Noise Signature

Early detection of leaks in hazardous materials pipelines is essential to reduce product loss and damage to the environment. Small undetected leaks can result in very high clean-up costs and have the potential to grow to more serious failures. There are a variety of methods that can detect leaks in pipelines, ranging from manual inspection to advanced satellite based imaging. Typically, most operators opt for a combination of CPM where available, and direct observation methodologies including aerial patrols, ground patrols and public awareness programs that are designed to encourage and facilitate the reporting of suspected leaks. Permanent monitoring sensors based on acoustic or other technologies are also available. These methods can be costly, and none can reliably detect small leaks regardless of their location in the line. SmartBall is a radical new approach that combines the sensitivity of acoustic leak detection with the 100% coverage capability of in-line inspection. The free-swimming device is spherical and smaller than the pipe bore allowing it to roll silently through the line and achieve the highest responsiveness to small leaks. It can be launched and retrieved using conventional pig traps, but its size and shape allow it to negotiate obstacles that could otherwise render a pipeline unpiggable. The SmartBall technology was originally developed and successfully implemented for the water industry, and now refined for oil and gas pipelines over 4-inches in diameter. SmartBall has been proven capable of detecting leaks in liquid lines of less than 0.1 gallons per minute where conventional CPM methods can detect leaks no smaller than 1% of throughput. Development work is continuing to reduce the detection threshold still further. Whereas traditional acoustic monitoring techniques have focused on longitudinal deployment and spacing of acoustic sensors, the SmartBall uses only a single acoustic sensor that is deployed inside the pipeline. Propelled by the flow of product in the pipeline, the device will record all noise events as it traverses the length of the pipeline. This allows the acoustic sensor to pass in very close proximity to any leak whereby the sensor can detect very small leaks, whose noise signature can be clearly distinguished from any background noise.

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GEOLOGICAL CONSIDERATION FOR CO2 STORAGE IN INDONESIA: A BASINAL SCALE OUTLOOK

Journal of Applied Geology ◽

10.22146/jag.7224 ◽

2015 ◽

Vol 1 (1) ◽

Author(s):

Hendra Amijaya

Keyword(s):

Carbon Dioxide ◽

Oil And Gas ◽

Carbon Dioxide Capture ◽

Co2 Storage ◽

Geothermal Gradient ◽

Gas Reservoirs ◽

Coal Beds ◽

North East ◽

Geological Conditions ◽

And Storage

Carbon dioxide capture and storage (CSS) is alternative of reducing atmospheric emissions of CO2. The concepts of CO2 storage refer to the injection of carbon dioxide in dense form into aquifers, which basically must meet several conditions. Three types of geological formations that can be used for the geological storage of CO2 are oil and gas reservoirs, deep saline formations and unmineable coal beds. Indonesia has 60 Tertiary basins, however that great precautions must be taken for selecting particular sedimentary basin in Indonesia for carbon dioxide storage because of high possibility of leakage and the need to find deep formations as CO2 host since the geothermal gradient is high. One possibility to find proper basins is by selected “mature” basin as the detailed geological conditions are well known. Candidates are are North East Java or South Sumatra Basins. Keywords: Carbon dioxide capture, storage, emission, basin.

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