Naslov (srp)

Uticaj paleosredine na raspodelu i obilnost zasićenih i aromatičnih ugljovodonika u sedimentima topličkog basena : doktorska disertacija

Autor

Burazer, Nikola M., 1991-

Doprinosi

Kašanin-Grubin, Milica, 1969-
Jovančićević, Branimir, 1962-
Stojanović, Ksenija, 1971-
Šajnović, Aleksandra, 1974-
Vasić, Nebojša D., 1954-

Opis (srp)

Osnovni cilj ove doktorske disertacije bio je proučavanje uticaja paleosredine taloženja naraspodelu i relativnu obilnost zasićenih i aromatičnih ugljovodonika u miocenskim jezerskimsedimentima Topličkog basena. Rezultati ovog istraživanja omogućili su procenu porekla, naftno-gasnog potencijala i zrelosti organske supstance u ispitivanim sedimentima. Takođe, ova disertacijaje razmatrala uticaje sedimentoloških procesa i tektonike na razvoj Topličkog basena i sastavsedimenata. Toplički basen do sada nije bio predmet ovakve vrste naučnih istraživanja.Ovo istraživanje je obuhvatalo interdisciplinarnu analizu i interpretaciju organskog ineorganskog dela odabranih sedimenata iz četiri istražne bušotine: BL3, BL4, BL5 i BL7. Neorganskideo je ispitivan primenom optičkih ispitivanja, rendgenske difraktometrije, rendgenske fluorescentnespektroskopije, indukovane kuplovane plazme sa masenom spektrometrijom, skenirajuće elektronskemikroskopije, kompleksometrijske analize sadržaja kalcijuma i magnezijuma. Organski deosedimenata je analiziran upotrebom petrografskih ispitivanja, Rok-Eval pirolize igasnohormatografsko-masenospektrometrijske metode.Na osnovu sedimentoloških, litoloških i mineraloških rezultata, Toplički basen je podeljen nazapadnu i istočnu subbasensku jedinicu. U dubljoj, zapadnoj subbasenskoj jedinici, ispitivani susedimenti bušotine BL7, dok su u plićoj, istočnoj subbasenskoj jedinici, ispitivani sedimenti bušotineBL3 i BL5. Bušotina BL4 nalazi se blizu prelaza između dve subbasenske jedinice, preko kojeg jeomogućena potencijalna komunikacija zapadnog i istočnog dela basena. Postojanje dve nezavisnesubbasenske jedinice omogućila je proučavanje uticaja različitih procesa na taloženje sedimenata ikarakteristike organske supstance. Pored navedenog, na osnovu litoloških i mineraloških podataka,miocenski sedimenti su raščlanjeni na nekoliko litofacijalnih jedinica koje su se međusobnorazlikovale po strukturnim i teksturnim osobenostima. U okviru ove disertacije detaljno su ispitivanitufozni, analcimizirani i bituminozni finozrni klastiti Čučala i finozrni klastiti Prebreze, taloženi ujezerskoj ili močvarnoj faciji. Sedimenti močvarne facije odlikuju samo bušotinu BL5.Vulkanizam je pratio taloženje sedimenata u Topličkom basenu, što se odražavalo krozprisustvo vulkanoklastičnog materijala duž vertikalnih profila ispitivanih bušotina.Vulkanski procesi su bili izraženiji u zapadnoj subbasenskoj jedinici, na šta je upućivao višisadržaj analcima u sedimentima bušotine BL7, kao i pojava tufogenog paketa, debljine 7 m. Značajnakoličina vulkanoklastičnog materijala koja je transportovana sa zapadnog dela u basen, podstakla jeproliferaciju algalnih i planktonskih zajednica, istovremeno pospešujući primarnu bioproduktivnost,što je uticalo na sadržaj organske supstance. Razvoj Topličkog basena praćen je tektonskimistanjivanjem kore, što je dovelo do pojačanog termalnog fluksa iz litosfere, čime je prouzrokovanopregrevanje organske supstance, koje je dalje podstaklo proizvodnju ugljovodonika i povećanjenjihovog ukupnog sadržaja. Organska supstanca sedimenata bušotine BL7 je nematurisana do ranomaturisana i izgrađena od kerogena tipa I ili II, koji imaju tendenciju ga generisanju tečnihugljovodonika. Akumulacija i očuvanje organske supstance u sedimentima BL7 je bilo omogućenozahvaljujući anoksičnim i mezo-slanim ili hiperslanim paleouslovima sredine, o kojima svedočipredominacija fitana, prisustvo i-C30, β-karotana, perilena, gamacerana, δ-metiltrimetildecilhromana,1,5- i 1,4-dimetilkarbazola.Taloženje sedimenata u istočnom delu Topličkog basena praćeno je intenzivnim aluvijalno-jezerskim procesima, što se odrazilo kroz izraženo prisustvo peskovite i šljunkovite komponente dužvertikalnog profila bušotine BL3, a u manjem obimu i u bušotini BL5. Peskovi i šljunkovi suznačajnije razblažili organsku supstancu ispitivanih sedimenata, koja je nematurisana i izgrađena odkerogena tipa III ili mešovitog kerogena tipa II/III. Predominacija viših neparnih n-alkana (n-C27, n-C29 i n-C31) i hopana u sedimentima bušotine BL3 i BL5, upućivali su na pojačano učešće višihkopnenih biljaka i mikrobiološki prerađene organske supstance. Sredina sedimentacije je bilageneralno anoksična i veoma dinamična. Na dinamiku sedimentacije uticala je energija jezera iDoktorska disertacija Nikola M. Burazeraluvijalni sistem putem kojeg se transportovala velika količina klastičnog materijala različite veličine.Klastični materijal je sa sobom dopremao organsku supstancu različitog porekla i stratigrafskepripadnosti, time ukazujući na prisustvo resuspendovane organske supstance u istočnoj subbasenskojjedinici. Organska supstanca, istaložena pod ovakvim okolnostima, je odražavala kompleksneinformacije o paleosredini taloženja.S obzirom da su više kopnene biljke dominantan prekursor u organskoj susptanci bušotina BL3i BL5, postojala je mogućnost razmatranja uticaja paleoklimatskih uslova na raspodelu i obilnostugljovodonika. Paleoklimatski uslovi su odražavali pojavu određenih biljnih taksona u organskojsupstanci ispitivanih sedimenata. Naime, visoke C-value i Rb/Sr, odnosno niske vrednosti Sr/Cuodnosa, praćene obilnijim učešćem zasićenih i aromatičnih triterpenoida koji vode poreklo odskrivenosemenica, odlikovali su veliku grupu ispitivanih sedimenata. Rezultati neorganskihgeohemijskih parametara i prisustvo skrivenosemenica odražavali su tople i semi-humidne/semi-aridne do semi-humidne paleoklimatske uslove sredine. Dobijeni podaci su u skladu sa dosadašnjimpaleoklimatskim istraživanjima neogenih basena jugoistočnog dela Evrope.S druge strane, tektonski procesi rastezanja kore i izdizanje (ekshumacija) Jastrebačkogkompleksa su pratili razvoj Topličkog basena tokom neogena. Razlike u sedimentološkim, litološkim,mineraloškim i organsko-geohemijskim osobenostima duž vertikalnog profila bušotine BL4, ukazalesu na pojavu cikličnosti u taloženju i četiri litočlana, A, B, C i D. U ovom slučaju cikličnost jepovezana sa tektonskim procesima. Naime, stvaranje prirodne „barijere“, u vidu ekshumiranogJastrebačkog kompleksa, kontrolisalo je prinos klastičnog materijala sa margina u zapadni i istočnideo ispitivanog basena. Tokom inicijalne faze razvoja Topličkog basena, prirodna „barijera“ jesprečila transport erodovanog materijala koji je odlikovao sedimente istočne subbasenske jedinice.Litočlanovi A i B odražavali su tip organske supstance i paleouslove slične kao u sedimentimazapadnog dela Topličkog basena (bušotina BL7). Mirna, anoksična i mezoslana sredina sedimentacije,pohranjena makro- i mikro- nutrijentima oslobođenih tokom vulkanskih procesa, odlikovala jeorgansku supstancu litočlanova A i B. O ovome svedoče znatne količine analcima, predominacijafitana, značajnije koncentracije i-C25 i i-C30, kao i izraženo prisustvo β-karotana. Organska supstancabila je pretežno obogaćena algalnim prekursorima.Sedimentacija se nastavila formiranjem litočlanova C i D. U tom trenutku, prirodna „barijera“ jesprečavala transport erodovanog materijala sa zapadne subbasenske jedinice. U ovom slučaju,organska supstanca odražavala je tip i paleouslove slične kao u sedimentima istočnog dela Topličkogbasena (bušotine BL3 i BL5). Organska susptanca bila je mešovitog porekla, istaložena u anoskično-disoksičnim i slatkovodnim uslovima sredine. U prilog iznešenom, potvrdu je predstavljalo iizraženije prisustvo peskovite komponente dopremljene aluvijalnim sistemom, promenljive vrednostiPr/Ph odnosa, smanjene relativne koncentracije i-C25 i i-C30, kao i odsustvo β-karotana.Sedimentacija u Topličkom basenu se okončala prinošenjem grubozrnih i srednjozrnih klastitasa svih margina, čime se polagano završila sedimentacija i nagovestilo gašenje neogenog jezerskogbasena.

Opis (srp)

Hemia - Geohemija / Chemistry - Geochemistry Datum odbrane: 23.11.2023.

Opis (eng)

The main goal of this doctoral dissertation was to study the influence of the paleoenvironmentalconditions on the distribution and relative abundance of saturated and aromatic hydrocarbons in theMiocene lake sediments of the Toplica basin. The results of this research enabled the assessment ofthe origin, oil and gas potential and maturity of the organic matter in the investigated sediments. Also,this dissertation considered the influence of sedimentological processes and tectonics on thedevelopment of the Toplica basin and composition of sediments. The Toplica basin has not been thesubject of previous scientific investigations.The research included an interdisciplinary analysis and interpretation of the organic andinorganic parts of selected sediments from four boreholes: BL3, BL4, BL5 and BL7. Examination ofthe inorganic part of the sediments was made possible by applying optical examinations, X-raydiffractometry, X-ray fluorescence spectroscopy, Inductively coupled plasma mass spectrometry,scanning electron microscopy, and complexometric analysis of calcium and magnesium content. Theorganic part of the sediments was analyzed using petrographic tests, Rock-Eval pyrolysis and gaschromatography-mass spectrometry methods.Based on sedimentological, lithological and mineralogical results, the Toplica basin wasdivided into western and eastern sub-basin units. In the deeper, western subbasin unit, the sedimentsof borehole BL7 were investigated, while in the shallower, eastern subbasin unit, the sediments ofboreholes BL3 and BL5 were examined. The BL4 borehole was located near the transition betweenthese sub-basin units, through which the potential communication of the western and eastern parts ofthe basin was probable. The existence of two independent sub-basin units opened the possibility ofstudying the influence of different processes on the deposition of sediments and the characteristics oforganic matter. In addition to the above, lithological and mineralogical data allowed thecategorization of Miocene sediments into several lithofacies, which were different in terms ofstructural and textural properties. Within the framework of this dissertation, the tuffaceous,analcimized and bituminous fine-grained clastites of Čučale and fine-grained clastites of Prebrezadeposited in lake or swamp lithofacies were examined. Swamp sediments were only detected withinthe borehole BL5.Volcanism characterized the deposition of sediments in the Toplica basin, which was reflectedin the presence of volcaniclastic material along the vertical profiles of the examined boreholes.Volcanic processes were more pronounced in the western subbasin unit, which was indicatedby the higher content of analcime in the sediments of borehole BL7, as well as the appearance of a 7m thick package of tuffs. Significant proportions of volcaniclastic material transported from thewestern part into the basin enhanced the proliferation of algal and planktonic communities,simultaneously increasing primary productivity, which affected organic matter content. Thedevelopment of the Toplica Basin was accompanied by crustal thinning that led to an increasedthermal flux from the lithosphere, which caused overheating of the organic matter and furtherstimulated the production of hydrocarbons and an increase in their total content. The organic matterin sediments of the borehole BL7 was immature to early mature and composed of type I or II kerogens,which tend to generate liquid hydrocarbons. The accumulation and preservation of organic matter inBL7 sediments were attributed to the anoxic and meso-saline or hypersaline paleoenvironmentalconditions, which is evidenced by the predominance of phytane, presence of i-C30, β-carotane,perylene, gammacerane, δ-methyltrimethyltridecyl chroman, 1,5- and 1,4-dimethyl carbazoles.The deposition of sediments in the eastern part of the Toplica basin was characterized by intensealluvial-lacustrine processes, which were reflected in the pronounced presence of sand and gravelcomponents throughout the borehole BL3 and, to a lesser extent, in well BL5. Sand and gravelcomponents significantly diluted the organic matter of the investigated sediments, which wasimmature and consisted of type III kerogen or mixed type II/III kerogen. The predominance of oddDoktorska disertacija Nikola M. Burazerlong-chain n-alkanes (n-C27, n-C29 and n-C31) and hopane in investigated sediments indicated anincreased participation of higher plants or microbiologically reworked organic matter. Thepaleoenvironmental conditions were generally anoxic and very dynamic. The sedimentationdynamics were influenced by the energy of the lake and the alluvial system through which a largeamount of clastic material of different sizes was transported. The clastic material transported organicmatter of mixed origins and stratigraphy, indicating resuspended organic matter in the easternsubbasin unit. The organic matter deposited under these circumstances reflected complex informationabout paleoenvironmental conditions.Given that higher terrestrial plants were the dominant precursor in the organic matter ofboreholes BL3 and BL5, the possibility of considering the influence of paleoclimatic conditions onthe distribution and relative abundance of hydrocarbons opened up. Paleoclimatic conditions reflectedthe occurrence of specific plant taxa in the organic matter of the investigated sediments. Namely, highC-value and Rb/Sr ratios, low Sr/Cu ratio values, followed by greater participation of saturated andaromatic triterpenoids originating from angiosperms, characterized a large group of investigatedsediments. The results of inorganic geochemical parameters and the presence of angiospermssuggested warm and semi-humid/semi-arid to semi-humid paleoclimate conditions. The obtained datawere in accordance with the previous paleoclimatic research of Neogene basins of the southeasternpart of Europe.On the other hand, tectonic processes of crustal extension and uplift (exhumation) of theJastrebac complex followed the development of the Toplica basin during the Neogene. Differencesin sedimentological, lithological, mineralogical and organic-geochemical characteristics along thevertical profile of the BL4 borehole indicated the occurrence of cyclicity in deposition andlithomembers A, B, C and D. In this case, cyclicity is associated with tectonic processes. Theformation of a natural "barrier" (exhumed Jastrebac complex) controlled the flow of clastic materialfrom the margins to the western and eastern parts of the studied basin. During the initial phase of thedevelopment of the Toplica basin, a natural "barrier" prevented the transport of eroded material thatcharacterized the sediments of the eastern sub-basin unit. Therefore, lithomembers A and B reflectedthe type of organic matter and paleoenvironmental conditions similar to those in the sediments of thewestern part of the Toplica basin (borehole BL7). A calm, anoxic and mesosaline paleoenvironment,stored with macro- and micro-nutrients released during volcanic processes, characterized theformation of lithomembers A and B. This was evidenced by significant amounts of analcime, thepredominance of phytane, significant concentrations of i-C25 and i-C30, and the pronounced presenceof β-carotene. The organic matter was predominantly enriched in algal precursors.Sedimentation continued with the formation of lithomembers C and D. At that point, a natural"barrier" prevented the transport of eroded material from the western subbasin unit. Therefore, theorganic matter reflected the type and paleoenvironmental conditions similar to those in the sedimentsof the eastern part of the Toplica basin (boreholes BL3 and BL5). The organic matter was of mixedorigin, deposited under anoxic-dysoxic and freshwater environmental conditions. In support of this,a more pronounced presence of the sandy fraction supplied by the alluvial system, fluctuating valuesof the Pr/Ph ratio, reduced concentrations of i-C25 and i-C30, as well as the absence of β-carotenecharacterized these lithomembers.Sedimentation in the Toplička basin ended with the deposition of coarse-grained and medium-grained clastites from all margins, which slowly ended the sedimentation and indicated the extinctionof the Neogene lake basin.

Jezik

srpski

Datum

2023

Licenca

Ovo delo je licencirano pod uslovima licence
Creative Commons CC BY-NC-ND 3.0 AT - Creative Commons Autorstvo - Nekomercijalno - Bez prerada 3.0 Austria License.

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Predmet

OSNO - Opšta sistematizacija naučnih oblasti, Ciklična jedinjenja. Derivati benzola

OSNO - Opšta sistematizacija naučnih oblasti, Geohemija

Toplica basin, Miocene, lake sediments, sedimentology, tectonics, mineralogy, petrology, saturated and aromatic hydrocarbons, paleoenvironment, paleoclimate

OSNO - Opšta sistematizacija naučnih oblasti, Ciklična jedinjenja. Derivati benzola

OSNO - Opšta sistematizacija naučnih oblasti, Geohemija

Toplički basen, miocen, jezerski sedimenti, sedimentologija, tektonika, mineralogija, petrologija, zasićeni i aromatični ugljovodonici, plaeosredina, paleoklima