Evidence of epibenthic microbial mats in Early Jurassic (Sinemurian) tidal deposits, Kulla Gunnarstorp, southern Sweden
(2013) In Dissertations in Geology at Lund University GEOL01 20131Department of Geology
- Abstract
- Wrinkle structures, a type of microbially induced sedimentary structures (MISS) were found in Jurassic tidally deposited heterolites of Kulla Gunnarstorp, southern Sweden. Wrinkle structures are characterizeded by minute, commonly elongate crinkles on the upper bedding planes of fine grained arenites. These structures, as well as MISS in general, form in siliciclastic sediments due to bacterial secretion of extracellular polymeric substance (EPS), which is strongly cohesive. The wrinkle structures of the present study originated as thick epibenthic microbial mats, and are of the non-transparent type, meaning that underlying bedforms are completely concealed by the bacterial remains. Where the mat grew, EPS hindered erosion of the... (More)
- Wrinkle structures, a type of microbially induced sedimentary structures (MISS) were found in Jurassic tidally deposited heterolites of Kulla Gunnarstorp, southern Sweden. Wrinkle structures are characterizeded by minute, commonly elongate crinkles on the upper bedding planes of fine grained arenites. These structures, as well as MISS in general, form in siliciclastic sediments due to bacterial secretion of extracellular polymeric substance (EPS), which is strongly cohesive. The wrinkle structures of the present study originated as thick epibenthic microbial mats, and are of the non-transparent type, meaning that underlying bedforms are completely concealed by the bacterial remains. Where the mat grew, EPS hindered erosion of the substrate, thus changing the premises of the physical distribution of sediments.
The wrinkle structures were exclusively found on the upper bedding planes of wavy bedded micaceous arenites whose bioturbation indices range from 2–4. Microbial mat formation and preservation was facilitated since bioturbation and grazing was restricted by the fluctuating conditions (for instance regarding salinity) in the tidal depositional environment. (Less) - Abstract (Swedish)
- Skrynkelstrukturer, en typ av mikrobiellt inducerade sedimentstrukturer (MISS) har återfunnits i jurassiska tidalt avsatta heteroliter i skånska Kulla Gunnarstorp. Skrynkelstrukturer kännetecknas av små, ofta avlånga veck på överytan av finkorniga sandstenar. Dessa strukturer, liksom MISS i allmänhet, bildas i siliciklastiska sediment under inverkan av bakteriellt utsöndrad extracellulär polymerisk substans (EPS), vilket är starkt kohesivt.
Skrynkelstrukturerna i den aktuella avhandlingen härrör från tjocka, epibentiska bakteriemattor, och är av den icke-transparenta typen, vilket innebär att underliggande bäddformer helt täcks av de bakteriella lämningarna. Där mattan växte hindrades erosionen av EPS och på detta vis ändrades premisserna... (More) - Skrynkelstrukturer, en typ av mikrobiellt inducerade sedimentstrukturer (MISS) har återfunnits i jurassiska tidalt avsatta heteroliter i skånska Kulla Gunnarstorp. Skrynkelstrukturer kännetecknas av små, ofta avlånga veck på överytan av finkorniga sandstenar. Dessa strukturer, liksom MISS i allmänhet, bildas i siliciklastiska sediment under inverkan av bakteriellt utsöndrad extracellulär polymerisk substans (EPS), vilket är starkt kohesivt.
Skrynkelstrukturerna i den aktuella avhandlingen härrör från tjocka, epibentiska bakteriemattor, och är av den icke-transparenta typen, vilket innebär att underliggande bäddformer helt täcks av de bakteriella lämningarna. Där mattan växte hindrades erosionen av EPS och på detta vis ändrades premisserna för den rent fysiska distributionen av sediment.
Skrynkelstrukturerna återfanns uteslutande på det övre bäddplanet glimmerrika areniter, vilkas bioturbationsindex varierar mellan 2–4. Bildning och bevaring av bakteriemattan möjliggjordes då bioturbation och betning hölls nere av de fluktuerande förhållandena (avseende bl. a. salthalt) som rådde i den tidala bildningsmiljön. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/3809529
- author
- Peterffy, Olof LU
- supervisor
- organization
- alternative title
- Bevis på epibentiska mikrobiella mattor i tidala avlagringar från äldre jura (Sinemurian), Kulla Gunnarstorp i Skåne
- course
- GEOL01 20131
- year
- 2013
- type
- M2 - Bachelor Degree
- subject
- keywords
- Sweden, Kulla Gunnarstorp, jurassic, wrinkle structures, microbially induced sedimentary structures, skrynklestrukturer, mikrobiellt inducerade sedimentstrukturer, jura, Sverige
- publication/series
- Dissertations in Geology at Lund University
- report number
- 345
- language
- English
- id
- 3809529
- date added to LUP
- 2013-06-11 12:25:03
- date last changed
- 2013-06-11 12:25:03
@misc{3809529, abstract = {{Wrinkle structures, a type of microbially induced sedimentary structures (MISS) were found in Jurassic tidally deposited heterolites of Kulla Gunnarstorp, southern Sweden. Wrinkle structures are characterizeded by minute, commonly elongate crinkles on the upper bedding planes of fine grained arenites. These structures, as well as MISS in general, form in siliciclastic sediments due to bacterial secretion of extracellular polymeric substance (EPS), which is strongly cohesive. The wrinkle structures of the present study originated as thick epibenthic microbial mats, and are of the non-transparent type, meaning that underlying bedforms are completely concealed by the bacterial remains. Where the mat grew, EPS hindered erosion of the substrate, thus changing the premises of the physical distribution of sediments. The wrinkle structures were exclusively found on the upper bedding planes of wavy bedded micaceous arenites whose bioturbation indices range from 2–4. Microbial mat formation and preservation was facilitated since bioturbation and grazing was restricted by the fluctuating conditions (for instance regarding salinity) in the tidal depositional environment.}}, author = {{Peterffy, Olof}}, language = {{eng}}, note = {{Student Paper}}, series = {{Dissertations in Geology at Lund University}}, title = {{Evidence of epibenthic microbial mats in Early Jurassic (Sinemurian) tidal deposits, Kulla Gunnarstorp, southern Sweden}}, year = {{2013}}, }