Long-term Investigation of Sr- Isotope and Rare Earth Element Fractionation Processes Within Three Major Aquifers in the Äspö Hard Rock Laboratory (Sweden)

Year:

2015

Type of Publication:

Article

Authors:

Hengsuwan, Manussawee; Heim, Christine; Hansen, Bent T.

Journal:

Geomicrobiology Journal

Volume:

32

Number:

3-4

Pages:

243-254

BibTex:

@article{doi:10.1080/01490451.2014.962121, author = "Manussawee Hengsuwan and Christine Heim and Bent T. Hansen", abstract = " The 450 m deep {\"A}sp{\"o} Hard Rock Laboratory ({\"A}sp{\"o} HRL) provides a unique opportunity to access different aquifer systems within the Precambrian granodioritic basement of the Baltic Shield. In this study, emphasis will be placed on systematic variations of the isotopic and chemical composition including fractionation patterns of rare earth elements (REE) of three different aquifers. The aim is to identify end-member groundwater compositions and increase the knowledge and understanding of the groundwater evolution, and water rock interaction, parameters which are important for the subsurface microbial activity in the {\"A}sp{\"o} HRL. Groundwaters at the shallow and intermediate aquifers were influenced most from Baltic Sea water and meteoric water. The analyses of Sr-data and REE show especially long-term groundwater-rock interaction and δ18O values indicate the presence of glacial meltwater in the deep aquifer. During the 5 years of investigation, significant chemical changes caused by internal mixing processes or present microbial activity were not observed. ", doi = "10.1080/01490451.2014.962121", journal = "Geomicrobiology Journal", number = "3-4", pages = "243-254", title = "{L}ong-term {I}nvestigation of {S}r- {I}sotope and {R}are {E}arth {E}lement {F}ractionation {P}rocesses {W}ithin {T}hree {M}ajor {A}quifers in the {\"{A}}sp{\"o} {H}ard {R}ock {L}aboratory ({S}weden)", url = "http://dx.doi.org/10.1080/01490451.2014.962121 ", volume = "32", year = "2015", }

Abstract:

The 450 m deep Äspö Hard Rock Laboratory (Äspö HRL) provides a unique opportunity to access different aquifer systems within the Precambrian granodioritic basement of the Baltic Shield. In this study, emphasis will be placed on systematic variations of the isotopic and chemical composition including fractionation patterns of rare earth elements (REE) of three different aquifers. The aim is to identify end-member groundwater compositions and increase the knowledge and understanding of the groundwater evolution, and water rock interaction, parameters which are important for the subsurface microbial activity in the Äspö HRL. Groundwaters at the shallow and intermediate aquifers were influenced most from Baltic Sea water and meteoric water. The analyses of Sr-data and REE show especially long-term groundwater-rock interaction and δ18O values indicate the presence of glacial meltwater in the deep aquifer. During the 5 years of investigation, significant chemical changes caused by internal mixing processes or present microbial activity were not observed.