Spatial Correlation Analysis between Acoustic Basement Depth and Marine Magnetic Anomalies Derived from Sub-Bottom Profiling and Marine Magnetic Survey Data in the Offshore Area of Ulsan Port

Eun Min Yeo; Chan Su Kim; Seung Pyo Choi; Sung-Ryul Shin; Wookeen Chung

doi:10.7582/GGE.2026.29.3.149

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2026 Vol.29, Issue 3 Next Page

Spatial Correlation Analysis between Acoustic Basement Depth and Marine Magnetic Anomalies Derived from Sub-Bottom Profiling and Marine Magnetic Survey Data in the Offshore Area of Ulsan Port 울산항 해역에서의 천부지층탐사 음향상 기반암과 해양 자력탐사 자기이상 사이의 공간적 상관관계 분석

31 August 2026. pp. 149-161

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Abstract

This study quantitatively analyzed the spatial correlation between acoustic basement depth and magnetic anomalies by integrating Chirp sub-bottom profiler (SBP) data and marine magnetic survey data acquired off Ulsan Port. Acoustic basement depth and magnetic anomalies were normalized to a 0–10 range, and their variation patterns were compared along representative survey lines. For the combined dataset of three representative lines, the Pearson correlation coefficient was r = –0.802 and the Spearman rank correlation coefficient was ρ = –0.845, indicating a strong negative correlation. This result implies an inverse spatial relationship in which magnetic anomalies are larger where the acoustic basement is shallower. However, in sections with thick sedimentary cover and weak reflector continuity, uncertainty in acoustic basement interpretation may increase, suggesting the need for additional validation. Despite these limitations, the joint application of sub-bottom profiling and marine magnetic surveys provides an effective approach for improving the reliability of shallow stratigraphy and basement structure interpretation in port and coastal areas.

Keywords

Sub-Bottom Profiling

Marine Magnetic Survey

Acoustic Basement Depth

Magnetic Anomaly

Correlation

본 연구에서는 울산항 해역에서 취득한 천부지층탐사(Chirp SBP)와 해양 자력탐사 자료를 통합하여, 음향상 기반암 심도와 자기이상의 공간적 상관관계를 정량적으로 분석하였다. 음향상 기반암 심도와 자기이상을 0–10 범위로 정규화한 후, 대표 측선에서 두 변수의 변화 양상을 비교하였다. 세 대표 측선 통합 자료에서 Pearson 상관계수 r = −0.802, Spearman 순위상관계수 ρ = −0.845로 나타나 강한 음의 상관관계가 확인되었다. 이는 기반암이 얕을수록 자기이상이 크게 나타나는 반비례적 공간 관계를 의미한다. 다만 퇴적층이 두껍고 반사면 연속성이 약한 구간에서는 음향상 기반암 해석의 불확실성이 증가할 수 있으므로 추가 검증이 필요하다. 이러한 한계를 고려하더라도, 천부지층탐사와 해양 자력탐사의 병행은 항만 및 연안 지역에서 천부 지층과 기반암 구조 해석의 신뢰성을 높이는 데 유효한 접근법임을 보여준다.

키워드

천부지층탐사

해양 자력탐사

음향상 기반암 심도

자기이상

상관관계

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Information

Publisher :Korean Society of Earth and Exploration Geophysicists
Publisher(Ko) :한국지구물리물리탐사학회
Journal Title :Geophysics and Geophysical Exploration
Journal Title(Ko) :지구물리와 물리탐사
Volume : 29
No :3
Pages :149-161
Received Date : 2026-05-14
Revised Date : 2026-06-10
Accepted Date : 2026-08-14
DOI :https://doi.org/10.7582/GGE.2026.29.3.149

Geophysics and Geophysical Exploration ISSN:1229-1064(Print) 2384-051X(Online) 지구물리와 물리탐사

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