Mixed-norm modeling of airborne tensor gravity and total field magnetic data to image the intrusion-related gabbroic budgell harbour stock

Didar, Fatemeh; Hosseini, Mojtaba; Abedi, Maysam; Ebrahim Zadeh Ardestani, Vahid; Mohammadi Saroughi, Zahra Sadat

doi:10.22059/ijmge.2026.413985.595371

Mixed-norm modeling of airborne tensor gravity and total field magnetic data to image the intrusion-related gabbroic budgell harbour stock

Document Type : Research Paper

Authors

Fatemeh Didar ¹

Mojtaba Hosseini ¹

Maysam Abedi ¹

Vahid Ebrahim Zadeh Ardestani ²

Zahra Sadat Mohammadi Saroughi ²

¹ School of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran.

² Institute of Geophysics, University of Tehran, Tehran, Iran.

10.22059/ijmge.2026.413985.595371

Abstract

This study examines the subsurface architecture of a gabbroic body located in the Newfoundland region (Newfoundland and Labrador, Canada) by analyzing tensor gravity and total magnetic intensity data. The primary objective is to assess the effectiveness of various regularization strategies within a mixed-norm inversion framework for improving the reconstruction of the geometry and physical property distribution of the gabbroic body and its associated anomalous zones. To this end, following initial preprocessing, the gravity and magnetic datasets were inverted under three scenarios employing mixed , and norm configurations, respectively, thereby enabling a comparative evaluation of the influence of sparsity versus smoothness constraints on inversion outcomes. The results demonstrate that sparser norms are more effective at delineating compact, high-contrast anomalous bodies, while smoother norms yield superior recovery of continuous structural features and regional background trends. A comparative analysis of the two datasets reveals that magnetic data exhibit greater sensitivity to variations linked to magnetic mineralization within the gabbroic body whereas gravity data offer more robust constraints on the overall geometry and density distribution of the body. All inversion experiments achieved stable convergence, and the resulting models successfully delineated both the primary structure of the body and its associated anomalous zones. Collectively, the findings of this study indicate that employing a mixed-norm inversion framework jointly with gravity and magnetic data constitutes an effective approach for reducing ambiguity and enhancing the interpretation of subsurface structures in complex geological settings, such as gabbroic intrusions.

Keywords

Mixed-norm

Gabbroic intrusion

Newfoundland

Gravity and magnetic

Inversion

Subjects

Geophysics

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