Här annonserar vi kontinuerligt nya förslag till examensarbeten på avancerad nivå (GEOR02, 45 hp). De senaste förslagen ligger överst och gamla tas bort efter hand som de blir inaktuella. Kontakta huvudhandledaren om du är intresserad. Du är dessutom alltid välkommen att utifrån dina egna intressen diskutera olika möjligheter med dina lärare. Här kan du se exempel på tidigare masterarbeten. Notera att du måste vara antagen till masterprogrammet i geologi vid Lunds universitet för att kunna genomföra ett av de föreslagna projekten.

Production and storage of fire derived black carbon in boreal forest soils

Black carbon (BC) is produced by incomplete combustion of biomass and fossil fuels and consists of carbon rich aromatic residues (char) and condensed carbon particles (soot). It is found in the atmosphere, ocean and inland waters, soils and sediments. It is of great significance for the carbon cycling on Earth and is one of the most important green-house substances. The high surface area can also function as an absorbent of other organic pollutants. BC particles are resistant to degradation and have a long residence time in soils and sediments and are considered a potential carbon sink. The natural production and storage and of BC in soils are therefore key factors in understanding the carbon cycle.

In this project we will measure BC content in soils from forests that burnt in the summer 2018. Our study sites include 50 forest fire sites from southern to norther Sweden, with additional control plots that have not burnt recently. In a previous study (Eckdahl et al in prep) we show that the BC stocks in the mineral soils doubled as a consequence of the forest fires. In this study we will analyse how and where these additional BC is stored in the mineral soils. The BC in soils can be either bound to mineral grains or as free particles in the soils. The research question is to answer if the added BC is in free particulate form or bound to mineral grains in the soils. This is a key question for understanding the cycling of naturally produced BC.

Project plan

The task is to set up a method for separating the mineral bound BC fraction from the free BC fraction. The separation of the two fractions will be achieved by sieving and heavy-liquid separation. BC of the fractions will be isolated by thermal and chemical oxidation, and quantified by flash-combustion elemental analysis. We will also use spectroscopic methods and microscopy to characterise the BC-fractions, potentially including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and x-ray photon spectroscopy (XPS).

The laboratory work will be at the Department of Geology during spring 2022.

The project can be either set up as a 30 or 45 credit project.

Is this for you?

This project is laboratory intense and is suitable if you want to develop laboratory skills and work in a research project. We think that you have some basic laboratory training from previous courses and want to work with new methods and method development.

Main supervisor: Karl Ljung (Geology Lund Univeristy).

Co-supervisors: Johan Eckdahl (Lund and Umeå Univeristy); Dan Metcalfe (Umeå University); Jeppe Kristensen (Oxford University)

Contact: Karl Ljung, karl [dot] ljung [at] geol [dot] lu [dot] se (karl[dot]ljung[at]geol[dot]lu[dot]se), 046-2223996

Inlagt: 2022-01-03

Age and origin of postglacial sediment slumps in Lake Siljan, central Sweden

As part of an ongoing project focussing on the deglaciation dynamics and subsequent lake development of the Siljan region in the county of Dalarna, sediment records from 20-50 m depth in Lake Orsajön have already been obtained. Together with detailed sonar-based bathymetry surveys, these investigations provide evidence of km-sized sediment slumps at great depths that probably took place in the early Holocene. To clarify their timing and triggering processes, similar slump deposits in the even larger and deeper Lake Siljan will be sampled by piston coring in the early spring of 2022. An opportunity for a master thesis project, preferably involving participation in the fieldwork, is offered based on this material. The methods involved will include age determination and age modelling based on radiocarbon dating, lithological and geochemical analyses of lake sediments, as well as interpretation of geophysical data. NOTE: The fieldwork is planned take place during the first week of March, so please let us know as soon as possible if you are interested.

Handledare: Dan Hammarlund, Per Möller, Karl Ljung
Inlagt: 2020-12-02
 

Solar storms in a paleoperspective

The recent discovery of abrupt short-term radionuclide production rate increases received considerable attention since they can be related to enormous solar storms (see e.g. https://www.iflscience.com/space/traces-giant-solar-storms-found/ ).  Such an event could have devastating effects on our technological infrastructure today. Significant efforts are nowadays focusing on high-resolution (annual) 14C measurements in tree rings to identify more of such events. However, ice core 10Be and 36Cl records have the potential to (i) increase the possibility for more reliable detection of such strong solar storm events and (ii) characterise such events in terms of number of particles and energy.

The master thesis will focus on the investigation of potential new solar storm events. It will likely involve ice core sampling at the ice core storage in Copenhagen and it will involve 10Be and 36Cl sample preparation at Lund University. The analysis will include an assessment of the likelihood of the identification of new solar storm event and an assessment of its characteristics.

Handledare: Raimund Muscheler, Florian Mekhaldi
Inlagt: 2019-01-24
 

Är du geologistudent och intresserad av arkeologi och palynologi?

Skriv ditt examensarbete inom projektet ”Arkeologi i Vännebo – en forskningsundersökning”

VAR?
I Roasjö socken, Svenljunga kommun, Västergötland (ca 20 mil norr om Lund) ligger Vännebosjön. Invid dess östra strand har vid tre tillfällen påträffats ett antal metallföremål som delvis utgjordes av förgyllda ryttardetaljer, vapen med mera som typologiskt kunnat dateras till folkvandringstiden, alltså ca 400-550 e. Kr.

VARFÖR?
Området är förhållandevis okänt trots sitt spektakulära fyndmaterial. Därför vill vi med hjälp av modern arkeologisk metodik och tvärvetenskapliga arbetssätt försöka förstå platsens utveckling under förhistorisk tid i allmänhet och folkvandringstid i synnerhet. Fanns det en boplats i anslutning till offerplatsen, var låg den i så fall? När etablerades den eventuella bebyggelsen och hur har landskapet och vegetationen förändrats i sjöns närhet under mellersta och yngre järnålder?

HUR?
Pollenanalys av sjösedimenten i Vännebosjön, gärna två borrkärnor – det blir Din uppgift!
Övriga tvärvetenskapliga metoder som kommer användas: markkemiska analyser, georadar- och magnetometerundersökningar, metalldetektering.

NÄR?
Målet är att genomföra fältarbetsmomenten (bland annat pollenanalyserna) under 2021 och 2022. Tidsramen är flexibel och beroende på hur analysresultaten faller ut kommer projektet förlängas.

Handledare: Karl Ljung, Anne Birgitte Nielsen
I samarbete med: Elinor Malmberg, Simon Karlsson, Kulturmiljö, VGR
Inlagt: 2021-04-16