A comparative study on some regional and local - residual separation of gravity anomalies for synthetic example and a case study from Mekong River, Vietnam

• Autorzy: Nguyen Hai , Nguyen Thanh , Dang Duy , To Loan

Identyfikatory

DOI

10.29227/IM-2025-01-02-028

• Konferencja: CESD 2024 : Conference on Earth Sciences : November 11th, 2024, Ho Chi Minh City, Vietnam
• Języki publikacji: EN

Abstrakty

EN

The division of anomalies into regional and local components is a critical and preliminary step when analyzing potential field data, including magnetic and gravity datasets. The regional component represents long-wavelength variations in the potential field associated with large-scale geophysical features, including crustal structures, tectonic boundaries, and density variations within the Earth's interior. Conversely, the residual component corresponds to shorter-wavelength variations linked to local geological structures or specific anomalies of interest. In Vietnam, researchers have employed various analytical methods such as the moving average (MA) and the quadratic least squares (QLS). However, due to the nonlinear and non-stationary nature of magnetic and gravity fields, these methods may not provide optimal solutions. In this study, we suggest a different method that utilizes bidimensional/image empirical mode decomposition (BEMD/iEMD) instead of Fourier and wavelet transforms. To assess the effectiveness of our method, we conducted validation using a gravitational anomaly model consisting of six spherical blocks, which yielded reliable results. Furthermore, we applied the MA, QLS, and iEMD methods to analyze Bouguer data from the Mekong River (in Vietnam), covering the region from the west of the Saigon River to the southwestern coastal area. Comparative analysis demonstrated that the iEMD method outperformed the MA and QLS methods as it allowed for simultaneous analysis of multiple local and regional components. This approach facilitated the generation of local maps and regional maps corresponding to the source field at various depths.

Słowa kluczowe

EN

gravity field; regional component; residual component; separating field technique; bidimensional/image empirical mode decomposition; Mekong river

PL

pole grawitacyjne; składowa regionalna; składowa resztkowa; technika rozdzielania pola; dekompozycja modów empirycznych dwuwymiarowa/obrazowa; rzeka Mekong

• Wydawca: Polskie Towarzystwo Przeróbki Kopalin
• Czasopismo: Inżynieria Mineralna
• Rocznik: 2025
• Tom: Vol. 2, no. 1
• Strony: art. no. 28
• Opis fizyczny: Bibliogr. 17 poz., rys., tab.

Twórcy

autor

Nguyen Hai

• Climate Change Institute, An Giang University, An Giang, Vietnam
• Faculty of Science, Nong Lam University, Ho Chi Minh City, Vietnam
• Vietnam National University, Ho Chi Minh City, Vietnam

autor

Nguyen Thanh

• Climate Change Institute, An Giang University, An Giang, Vietnam
• Vietnam National University, Ho Chi Minh City, Vietnam

autor

Dang Duy

• Faculty of Physics and Engineering Physics, University of Science, Ho Chi Minh City, Vietnam
• Vietnam National University, Ho Chi Minh City, Vietnam

autor

To Loan

• Personnel Office, An Giang University, An Giang, Vietnam
• Vietnam National University, Ho Chi Minh City, Vietnam

Bibliografia

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Uwagi

Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki i promocja sportu (2026).