Grain-Size Distribution and Structural Characteristics of Varved Sediments from Lake Żabińskie (Northeastern Poland)

Maurycy Żarczyński,Wojciech Tylmann,Jacek Szmańda

doi:10.3390/quat2010008

Maurycy Żarczyński, Wojciech Tylmann + Show 1 more

Open Access

https://doi.org/10.3390/quat2010008

Copy DOI

Abstract

Typically, the description of varve microfacies is based on microscopic sedimentary structures, while standard grain-size analysis is commonly applied with lower resolution. Studies involving a direct comparison of varve microfacies and particle-size distributions, common for clastic environments, are scarce for biogenic varves. In this study, we analyzed nine-year resolution grain-size data from Lake Żabińskie (northeastern Poland) to detect differences between varve microfacies. Six varve microfacies were differentiated using grain-size distributions and sedimentological attributes (calcite layer thickness, dark layer thickness, mass accumulation rate). However, changes in particle-size distributions between different varve types are relatively small and indicate a similar source for the material deposited. Decomposition of grain-size distributions with the end-member approach allows recognition of relative changes for the deposition of allochthonous (mineral) and autochthonous (carbonates, (hydr)oxides) components. Grain-size data suggest that sources of allochthonous material remained constant, while varve formation was controlled mostly by in-lake processes.

Highlights

IntroductionLacustrine sedimentary records are one of the most important paleoenvironmental archives [1]
Lacustrine sedimentary records are one of the most important paleoenvironmental archives [1].Among these, records with varved sediments offer a rare opportunity for annually resolved chronologies and analyses [2,3]
Records with varved sediments offer a rare opportunity for annually resolved chronologies and analyses [2,3]

Summary

Introduction

Lacustrine sedimentary records are one of the most important paleoenvironmental archives [1]. Records with varved sediments offer a rare opportunity for annually resolved chronologies and analyses [2,3]. Studies based on varved sediments require careful recognition and confirmation of the annual deposition cycle [4,5]. This is mostly achieved with microfacies analysis, which is based on recognition of microscopic sedimentary structures forming the varves [4,6]. Textural analysis, including particle-size of the accumulated material, provides one of the fundamental characteristics for the study of sedimentary material [12]. Grain-size analyses offer a variety of research opportunities for lacustrine settings

Objectives

Methods

Results

Discussion

Conclusion