Estimation of water layer correction in shallow time-lapse streamer data sets

Ong, Beng S.; Hembd, Jeshurun; Srinivasan, Arjun; Chu, Dez; Johnston, David H.

doi:10.1190/segam2015-5866701.1

Cited by 3 publications

(2 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This approach is not accurate when targeting the shallow reflectors near the sea floor because of limited near offset data and a poorly recorded water bottom. Therefore, Ong et al (2015) provided an extension to the method for the case of shallow water marine streamer datasets by including overburden reflectors in addition to the water bottom. The method will not work if there is a dip or 3D variations in the water layer.…”

Section: Tide and Seawater Velocity Variationsmentioning

confidence: 99%

See 1 more Smart Citation

A review and analysis of errors in post‐stack time‐shift interpretation

MacBeth

Izadian

2023

Geophysical Prospecting

View full text Add to dashboard Cite

This study complements two earlier papers on the interpretation and estimation of post‐stack time‐shifts that detail the most popular measurement methods to date. In this current work, the focus is on describing the magnitude and identifying the origin of the uncertainty present in these time‐shift values. We also consider how the underlying assumptions behind conventional time‐shift estimation methods can contribute to the inadequate resolution of the subsurface time‐lapse changes. The various errors fall into three broad categories: (1) those related to intrinsic data limits that cannot be avoided; (2) those associated with seismic measurement methods that can be corrected with some effort; and finally (3) those that arise due to approximations to the wave physics made during the design or implementation of the methods. In the first category are limitations due to sampling rate and signal‐to‐noise ratio, and wavelet interferences resulting from the narrow band nature of the seismic data and the heterogeneous nature of the geology itself. The effects produce errors of typically a fraction of a millisecond, but exceptionally in 4D data with poor repeatability up to 1 ms. In the second category are acquisition and processing errors. These are usually of the order of a few milliseconds but can reach up to 10s of milliseconds and are, therefore, essential to correct. It is possible to correct the effects of tides and seawater variations in marine acquisition if these changes are monitored and measured. Navigation and timing are identified as issues to consider carefully. For land data, daily and seasonal near‐surface variations are still problematic, and source and sensors must be buried to deliver interpretable time‐shifts. The impact of choices made during processing can be significant but is specific to the workflow and dataset and thus cannot be generically assessed. However, the effects from residual multiples can be identified and treated. Of moderate importance is the third category of errors, which consists of four items. Of these, the effect of lateral image shifts and amplitude effects are judged to play a minor role. Deviation from the assumption of vertical ray‐paths during post‐stack analysis appears to be of concern only for reservoirs with noticeably dipping structures and strong contrasts. The effect of pre‐stack variations on the post‐stack measurements remains a topic to be more thoroughly examined, and the conclusion is unclear. Finally, it is apparent that uncertainties in all categories are strongly dependent on the field setting and geographical location.

show abstract

Section: Tide and Seawater Velocity Variationsmentioning

confidence: 99%

“…Therefore, Ong et al. (2015) provided an extension to the method for the case of shallow water marine streamer datasets by including overburden reflectors in addition to the water bottom. The method will not work if there is a dip or 3D variations in the water layer.…”

Section: Acquisition and Processing‐related Errorsmentioning

confidence: 99%

A review and analysis of errors in post‐stack time‐shift interpretation

MacBeth

Izadian

2023

Geophysical Prospecting

View full text Add to dashboard Cite

show abstract

Correction of water column height variation on 2D grid high-resolution seismic data using dGPS based methodology

Abegunrin

Hepp

Mörz

2020

Sci Rep

View full text Add to dashboard Cite

Variations in the physical properties of water column usually impede exact water column height correction on high-resolution seismic data, especially when the data are collected in shallow marine environments. Changes in water column properties can be attributed to variation in tides and currents, wind-generated swells, long and short amplitude wave-fronts, or variation in salinity and water temperature. Likewise, the proper motion of the vessel complicates the determinability of the water column height. This study provides a less time-consuming and precise differential Global Positioning System based methodology that can be applied to most types of high-resolution seismic data in order to significantly improve the tracking and quality of deduced geological interpretations on smaller depth scales. The methodology was tested on geophysical profiles obtained from the German sector of the North Sea. The focus here was to identify, distinguish and classify various sub-surface sedimentary structures in a stratigraphically highly complex shallow marine environment on decimeter small-scale. After applying the correction to the profiles, the sea floor, in general, occurs 1.1 to 3.4 m (mean of 2.2 m) deeper than the uncorrected profiles and is consistent with the sea floor from published tide corrected bathymetry data. The corrected seismic profiles were used in plotting the depth of the base of Holocene channel structures and to define their gradients. The applied correction methodology was also crucial in glacial and post-glacial valley features distinction, across profile correlation and establishing structural and stratigraphic framework of the study area.

show abstract

Time-shift correction of towed streamer 4D seismic data for complex reservoirs

Zou

2016

SEG Technical Program Expanded Abstracts 2016

View full text Add to dashboard Cite

Estimation of water layer correction in shallow time-lapse streamer data sets

Cited by 3 publications

References 3 publications

A review and analysis of errors in post‐stack time‐shift interpretation

A review and analysis of errors in post‐stack time‐shift interpretation

Correction of water column height variation on 2D grid high-resolution seismic data using dGPS based methodology

Time-shift correction of towed streamer 4D seismic data for complex reservoirs

Contact Info

Product

Resources

About