مقا سهي پارامترهاي پي ز يرول راك-اول و بايوماركرها: مطالعه موردي سنگ منشاهورنوالي سيلتستون، مركز استرال ا

Comparative study between Rock-Eval pyrolysis and

در اﻳﻦ ﻣﻄﺎﻟﻌﻪ ﺗﻌﺪاد 44 ﻧﻤﻮﻧﻪ از ﺳﻨﮓﻫﺎي رﺳﻮﺑﻲ ﺳﺎزﻧﺪ ﻫﻮرن واﻟﻲ ﺳﻴﻠﺘﺴﺘﻮن (Horn Valley Siltstone) از ﺣﻮﺿﻪ آﻣﺎدﺋﻮس (Amadeus Basin) در ﻣﺮﻛﺰ اﺳﺘﺮاﻟﻴﺎ، ﺑﻪ وﺳﻴﻠﻪي دو روش ﺷﻴﻤﻴﺎﻳﻲ ﻴﭘ ، ﻴﺮوﻟ ﺰ راك-اول (R-E) و ﻛﺮوﻣﺎﺗﻮﮔﺮاﻓﻲ ﮔﺎزي_اﺳﭙﻜﺘﺮوﻣﺘﺮي ﺟﺮﻣﻲ (GC-MS) ﻣﻮرد ﺗﺠﺰﻳﻪ و ﺗﺤﻠﻴﻞ ﻗﺮار ﮔﺮﻓﺘﻪاﻧﺪ. اﻳﻦ روشﻫﺎ ﺑﺮاي ﺑﻪ دﺳﺖ آوردن ﭘﺎراﻣﺘﺮﻫﺎي ﻣﺴﺘﻘﻞ از ﺗﺮﻛﻴﺒﺎت ﻣﻮاد آﻟﻲ ﻣﺎﻧﻨﺪ ﺑﻠﻮغ ﺣﺮارﺗﻲ و ﻣﺤﻴﻂ رﺳﻮبﮔﺬاري اﺳﺘﻔﺎده ﻣﻲﺷﻮﻧﺪ. اﻳﻦ ﻣﻄﺎﻟﻌﻪ اﻧﻄﺒﺎق ﻧﺰدﻳﻜﻲ ﺑﻴﻦ اﻃﻼﻋﺎت ﺑﺪﺳﺖ آﻣﺪه از ﭘﻴ ﻴﺮوﻟ ﺰ راك-اول و ﺑﺎﻳﻮﻣﺎرﻛﺮﻫﺎي (biomarkers) ﭼﻨﺪ ﺣﻠﻘﻪاي ﻣﺎﻧﻨﺪ ﻫﭙﺎن (ﻫﺎ hopanes) و اﺳﺘﺮنﻫﺎ (steranes را ) ﻧﺸﺎن ﻣﻲدﻫﺪ. ﭘﻴ ﺰ ﻴﺮوﻟ RE و GC-MS ﻧﺸﺎن ﻣﻲدﻫﺪ ﻛﻪ رﺳﻮﺑﺎت ﺣﻮﺿﻪ آﻣﺎدﺋﻮس ﺣﺎوي رﺧﺴﺎرهﻫﺎي ﻏﻨﻲ ازﻣﻮاد آﻟﻲ در ﺗﻤﺎم ﺳﺎزﻧﺪ ﻫﻮرن واﻟﻲ ﺳﻴﻠﺘﺴﺘﻮن ﻣﻲﺑﺎﺷﺪ و ﮔﻮاه روﺷﻨﻲ ﺑﺮ ﻛﺮوژن ﻧﻮع II اﺳﺖ ﻛﻪ در ﻣﺮﺣﻠﻪ ﭘﻨﺠﺮه ﺗﻮﻟﻴﺪ ﻧﻔﺖ ﻗﺮار ﮔﺮﻓﺘﻪ ا ﺳﺖ (اواﺧﺮ دﻳﺎژﻧﺰ ـ اواﺳﻂ ﻛﺎﺗﺎژﻧﺰ). اﻳﻦ ﭘﮋوﻫﺶ در ﺣﻮﺿﻪ آﻣﺎدﺋﻮس، ﻧﺸﺎن ﻣﻲدﻫﺪ ﻛﻪ اﻳﻦ روشﻫﺎ ﺑﺪون ﺷﻚ ﺟﻬﺖ ارزﻳﺎﺑﻲ ﺻﺤﻴﺢ ﭘﺘﺎﻧﺴ ﻞﻴ ﻧﻔﺖ ﻳزا ﻲ ﺳﻨﮓﻫﺎي ﻣﻨﺸﺎ و ﺗﻮﺻﻴﻒ ﺳﺮﻳﻊ وﻳﮋﮔﻲﻫﺎي ژﺋﻮﺷﻴﻤﻴﺎﻳﻲ رﺳﻮﺑﺎت ﺣﺎوي ﻣﻮاد آﻟﻲ ﻣﻨﺎﺳﺐ ﻫﺴﺘﻨﺪ و ﻣﻲﺗﻮاﻧﺪ در ﺣﻮﺿﻪﻫﺎي ﻣﺸﺎﺑﻪ ﻧﻴﺰ ﻣﻮرد اﺳﺘﻔﺎده ﻗﺮار ﮔﻴﺮد.

In this study 44 Sedimentary rock samples from the Amadeus Basin, in southern portion of the Northern Territory, Australia, were analyzed by two well-proven organic geochemical methods: Rock-Eval (RE) pyrolysis and gas chromatography–mass spectrometry (GC–MS) analysis. These techniques were used to obtain independent parameters on organic matter composition, its thermal maturity, and environment of deposition. This study reveals a close concordance between Rock-Eval pyrolysis data and polycyclic biomarkers parameters such as steranes. RE pyrolysis in conjunction with GC–MS analysis show that the Amadeus Basin sediments contain a variable but notable organic-rich facies in the Horn Valley siltstone and prove an unequivocal evidence for Type-II organic matter, which lies dominantly to the peak stage of the conventional oil window (end of diagenesis-middle of catagenesis). The case study from the Amadeus Basin shows that these methods remain undoubtedly suitable for a good assessment of the petroleum potential of source rocks and rapid geochemical characterization of sedimentary organic matter, and can be used in other similar basins.