Analysis of Ocean Bottom Pressure Anomalies and Seismic Activities in the MedRidge Zone

Hakan S Kutoglu,Kazimierz Becek

doi:10.3390/rs13071242

Abstract

The Mediterranean Ridge accretionary complex (MAC) is a product of the convergence of Africa–Europe–Aegean plates. As a result, the region exhibits a continuous mass change (horizontal/vertical movements) that generates earthquakes. Over the last 50 years, approximately 430 earthquakes with M ≥ 5, including 36 M ≥ 6 earthquakes, have been recorded in the region. This study aims to link the ocean bottom deformations manifested through ocean bottom pressure variations with the earthquakes’ time series. To this end, we investigated the time series of the ocean bottom pressure (OBP) anomalies derived from the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) satellite missions. The OBP time series comprises a decreasing trend in addition to 1.02, 1.52, 4.27, and 10.66-year periodic components, which can be explained by atmosphere, oceans, and hydrosphere (AOH) processes, the Earth’s pole movement, solar activity, and core–mantle coupling. It can be inferred from the results that the OBP anomalies time series/mass change is linked to a rising trend and periods in the earthquakes’ energy time series. Based on this preliminary work, ocean-bottom pressure variation appears to be a promising lead for further research.

Highlights

The satellite gravimetry technique has been developed to measure gravity anomalies across the Earth
Using the periodogram function found in MatLab, we identified 10.66, 4.27, 1.52, and 1.02-year periods in the detrended ocean bottom pressure (OBP) time series
MedRidge is one of the most critical subduction zones in the world. This fault system has produced earthquakes > M8 that devastated the ancient cities in the region

Summary

Introduction

The satellite gravimetry technique has been developed to measure gravity anomalies across the Earth. The gravity anomalies are caused by mass variations, including those in ocean basins. The ocean basin mass variations are linked to changes in the hydrostatic pressure at the seafloor [1]. This hydrostatic pressure at the seafloor is known as the ocean bottom pressure (OBP). The OBP is the combined pressure caused by the column of seawater’s weight and the atmosphere above the seafloor [2]. The OBP can be derived from gravity anomaly data [3]

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Methods

Results

Discussion

Conclusion