Depositional patterns constrained by slope topography changes on seamounts

Dewen Du,Fengdeng Shi,Gang Yang,Qinglei Song,Shijuan Yan,Yingchun Cui,Xuefa Shi,Zhiwei Zhu,Fengli Yang

doi:10.1038/s41598-020-77573-2

Abstract

Slope topography is known to control the spatial distribution of deposits on intraplate seamounts; however, relatively little is known about how slope topography changes constrain those depositional patterns. In this study, we analyse data on four lithotypes found on seamount slopes, including colloidal chemical deposits comprising mainly cobalt-rich crusts, and examine the relationships between the spatial distribution of these lithotypes and current slope topography. We use these relationships to discuss depositional patterns constrained by slope topography changes. Some depositional units in drill core samples are interpreted to have resulted from past topographic changes that created the current slope topography. Two or more types of deposits that accumulated at the same location implies that the slope topography changed over time and that the depositional patterns on seamount slopes are constrained by changes in slope topography.

Highlights

Slope topography is known to control the spatial distribution of deposits on intraplate seamounts; relatively little is known about how slope topography changes constrain those depositional patterns
The Magellan Seamounts in the northwest Pacific Ocean (Fig. 1) are typical intraplate seamounts that were active during the Late Cretaceous
Many submarine environmental factors might constrain such depositional p atterns[18,19,20,21,22,23,24,25]; geologic surveys have demonstrated that topography is one essential factor constraining their spatial distribution on seamount slopes[12,15,26,27,28,29,30]

Summary

Introduction

Slope topography is known to control the spatial distribution of deposits on intraplate seamounts; relatively little is known about how slope topography changes constrain those depositional patterns. The loose sediments on the flat tops of seamounts are similar to pelagic sediments everywhere, transitional zone sediments and cobalt-rich crusts on seamount slopes have distinct depositional patterns when compared with deep-sea basin and continental margin sediments.

Results

Conclusion