川渝地區(qū)下三疊統(tǒng)海相碳酸鹽巖的碳氧同位素研究
發(fā)布時間：2018-07-29 12:17
【摘要】：地球與生命的起源、發(fā)展與演化一直是地球科學(xué)研究的熱點(diǎn)領(lǐng)域,早三疊世處于古—中生代地質(zhì)突變轉(zhuǎn)折期,因晚二疊世生物大滅絕和早三疊世蕭條的生態(tài)復(fù)蘇而受到了人們廣泛的關(guān)注。論文以四川盆地豐富的下三疊統(tǒng)碳酸鹽巖為研究載體,在異常地質(zhì)事件及異常沉積記錄背景下,對四川盆地6條地表剖面碳酸鹽巖樣品進(jìn)行了巖石學(xué)、元素和碳氧同位素分析,探討了早三疊世海相碳酸鹽巖碳同位素異常震蕩的可能驅(qū)動機(jī)制及早三疊世白云石與伴生方解石的碳氧同位素組成差異。利用薄片觀察、陰極發(fā)光、掃描電鏡及能譜分析等多項研究手段對研究區(qū)樣品進(jìn)行了詳細(xì)的巖石學(xué)特征研究,同時選擇Mn/Sr比值和δ18O值來評估樣品對海水地球化學(xué)信息的代表性。研究表明:泥微晶灰?guī)r對海水信息有較好的代表性,絕大多數(shù)顆�；�?guī)r、過渡巖類和白云巖在很大程度上保存了古海水的信息,重結(jié)晶灰?guī)r對古海水信息的代表性較差,而鹽溶角礫巖-次生灰?guī)r代表了表生環(huán)境的地球化學(xué)信息,其地球化學(xué)特征已經(jīng)明顯偏離了古海水的特征。在詳細(xì)的成巖蝕變評估基礎(chǔ)上建立了3條早三疊世海相碳酸鹽巖碳同位素演化曲線,并進(jìn)行了全球性與區(qū)域性對比,表明所建立的碳同位素演化曲線具有很好的全球和區(qū)域可對比性,顯示碳酸鹽巖碳同位素在晚二疊世-早三疊世經(jīng)歷了數(shù)次不同幅度的震蕩,主要包括P/T界線附近急劇的負(fù)偏移,Denerian-Smithian、Smithian-Spathian、Spathian-Anisian界線處的三次正漂移,共同構(gòu)成了早三疊世約5Myr的高頻率、大幅度的異常碳循環(huán)演化型式。碳同位素演化曲線顯示了δ~(13)C最小值約為-2‰,最大值約為6‰,震蕩幅度高達(dá)8‰。研究區(qū)海相碳酸鹽巖碳同位素演化曲線與大貴州灘關(guān)刀剖面建立的早三疊世碳酸鹽巖碳同位素曲線具有良好的對比性,但也存在一定的差異。關(guān)刀剖面整個早三疊世碳酸鹽巖碳同位素的峰值分布在Denerian-Smithian界線處,而我們建立的同期碳同位素曲線中2條剖面的峰值分布在Smithian-Spathian界線處,且峰值不及大貴州灘的峰值8‰。早三疊世碳循環(huán)的異常震蕩說明了早三疊世生態(tài)環(huán)境的不穩(wěn)定性和生物復(fù)蘇過程的復(fù)雜性。利用碳同位素地層學(xué)原理對研究區(qū)地層進(jìn)行了年代地層和巖石地層對比,表明飛仙關(guān)組可大致相當(dāng)于Induan階,嘉一段可大致相當(dāng)于Smithian階,嘉二段、嘉三段和嘉四段下部可大致相當(dāng)于Spathian亞階。在綜合巖石學(xué)、地球化學(xué)信息的基礎(chǔ)上探討了早三疊世碳酸鹽巖碳同位素大幅度波動的可能驅(qū)動機(jī)制,提出了單一的地質(zhì)事件不足以造成晚二疊世-早三疊世海水碳同位素幾乎對稱式的正漂移和負(fù)漂移。晚二疊世西伯利亞暗色巖系向大氣中輸入的輕碳可能會造成碳同位素負(fù)漂移1‰左右,與我們觀察到的碳酸鹽巖碳同位素負(fù)漂移程度相差甚遠(yuǎn),可能與火山噴發(fā)等地質(zhì)事件觸發(fā)的甲烷水合物釋放有關(guān)。然而對于早三疊世海水碳同位素幾乎對稱式的正漂移和負(fù)漂移,甲烷水合物釋放理論則難以解釋這一波動型式。這種波動型式可能與有機(jī)碳和無機(jī)碳埋藏率的周期性變化有關(guān),海水碳同位素正漂移可能和提高的有機(jī)碳埋藏率有關(guān)。在早三疊世白云巖比相鄰地層灰?guī)r有較高的碳同位素組成,我們在手標(biāo)本尺度上定量研究了早三疊世沉積溫壓條件下的白云石與伴生方解石的碳同位素組成差異,認(rèn)為白云石比伴生方解石的碳同位素偏正約2~2.6‰,這一結(jié)果與白云石化過程中的碳同位素分餾實驗和理論計算結(jié)果一致。碳酸鹽巖氧同位素易受成巖蝕變影響使得手標(biāo)本天然樣品中定量研究白云石和方解石的氧同位素差異沒有實際意義,但是可以肯定的是沉積溫壓條件下白云石比伴生方解石具有較高的氧同位素組成。
[Abstract]:The origin, development and evolution of the earth and life have been a hot field in the research of earth science. The early three fold period was in the palaeo Mesozoic geological catastrophe period. People paid much attention to the Late Permian biological mass extinction and the ecological resuscitation of the early three fold depression. The paper took the rich lower three carbonate rocks in the Sichuan basin as research. Under the background of abnormal geological events and abnormal sedimentary records, the petrology, elements and carbon and oxygen isotopes of the 6 surface profile carbonate samples of the Sichuan basin were analyzed. The possible driving mechanism of carbon isotopes in the early three fold marine carbonate rocks and the carbon and oxygen of the early three Permian dolomites and associated calcites were discussed. A number of research methods such as thin film observation, cathodoluminescence, scanning electron microscopy and energy spectrum analysis have been used to study the petrological characteristics of the samples in the study area. At the same time, the Mn/Sr ratio and delta 18O value are selected to evaluate the representative of the samples on the geochemical information of the sea water. The research shows that the mud microcrystalline limestone is better for the sea water information. Most of the granular limestone, transitional rock and dolomite, to a great extent, preserved the information of the ancient sea water, and the recrystallized limestone is less representative of the information of the ancient sea water, while the salt dissolving breccia - Secondary limestone represents the geochemical information of the epigenetic environment, and its geochemical characteristics have obviously deviated from the characteristics of the ancient sea water. On the basis of detailed diagenetic alteration assessment, the carbon isotope evolution curves of 3 early three fold marine carbonate rocks have been established, and a global and regional comparison is carried out. It shows that the carbon isotope evolution curve has a good global and regional contrast, showing that carbon isotopes of carbonate rocks experienced a number of late Permian early three generations. The oscillations at the different amplitude mainly include the sharp negative migration near the P/T boundary, the three positive drift of the Denerian-Smithian, Smithian-Spathian and Spathian-Anisian boundaries, which together constitute the high frequency of the early three superposition of about 5Myr and the large anomalous carbon cycle evolution pattern. The carbon isotope evolution curve shows that the minimum value of delta ~ (13) C is about -2 per thousand. The maximum value is about 6 per thousand and the amplitude of the oscillation is up to 8 per thousand. The carbon isotope evolution curve of the marine carbonate rock in the study area is well contrasted with the carbon isotope curves of the early three superposition carbonate rocks in the Guizhou beach cutting section, but there are some differences. The peak distribution of carbon isotopes of the early three carbonate rocks in the section of the Guan Dao section is in D At the enerian-Smithian boundary, the peak of 2 sections in the carbon isotope curve we set up in the same period is distributed at the Smithian-Spathian boundary, and the peak value is less than 8 per 1000 in the big Guizhou beach. The abnormal oscillation of the early three fold carbon cycle shows the instability of the early three fold ecological environment and the complexity of the biological resuscitation process. The principle of geostratigraphic stratigraphy has compared the stratigraphic and chronostratigraphy to the strata of the study area. It shows that the Feixianguan formation can be roughly equivalent to the Induan order. The Jijia section can be roughly equivalent to the Smithian order, the Jia two section, the Jijia three and the Jiayan four segments are roughly equivalent to the suborder of the Spathian. The possible driving mechanism of the large amplitude fluctuation of carbon isotopes in the three world carbonate rocks suggests that a single geological event is not sufficient to cause the positive drift and negative drift of the carbon isotopes of the Late Permian early three fold world. The light carbon input to the atmosphere in the Late Permian Siberia dark rock system may cause a negative carbon isotope drift of 1. The negative drift degree of carbon isotopes we observed in carbonate rocks is very far from that of the carbonate rocks we observed, which may be related to the release of methane hydrate triggered by volcanic eruptions. However, the theory of methane hydrate release is difficult to explain this wave pattern for the positive drift and negative drift of the early three superposition of the carbon isotopes of the sea water. This wave pattern may be related to the periodic changes of organic carbon and inorganic carbon burial rates. The positive drift of carbon isotopes in sea water may be related to the increase of organic carbon burial rates. In the early three fold dolomites, there was a higher carbon isotope composition than the adjacent stratigraphic limestone. We quantitatively studied the early three stack sedimentary warm pressure strips on the hand specimen size. The carbon isotope composition of dolomite and associated calcite is different from that of associated calcite, and it is believed that the carbon isotope of dolomite is about 2~2.6 per thousand than that of associated calcite. This result is consistent with the carbon isotope fractionation experiment and theoretical calculation in dolomitization. There is no practical significance for the quantitative study of oxygen isotope differences between dolomite and calcite, but it is certain that dolomite has a higher oxygen isotope composition than associated calcite under the condition of sedimentary temperature and pressure.
【學(xué)位授予單位】：成都理工大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2017
【分類號】：P588.245
本文編號：2152649
[Abstract]:The origin, development and evolution of the earth and life have been a hot field in the research of earth science. The early three fold period was in the palaeo Mesozoic geological catastrophe period. People paid much attention to the Late Permian biological mass extinction and the ecological resuscitation of the early three fold depression. The paper took the rich lower three carbonate rocks in the Sichuan basin as research. Under the background of abnormal geological events and abnormal sedimentary records, the petrology, elements and carbon and oxygen isotopes of the 6 surface profile carbonate samples of the Sichuan basin were analyzed. The possible driving mechanism of carbon isotopes in the early three fold marine carbonate rocks and the carbon and oxygen of the early three Permian dolomites and associated calcites were discussed. A number of research methods such as thin film observation, cathodoluminescence, scanning electron microscopy and energy spectrum analysis have been used to study the petrological characteristics of the samples in the study area. At the same time, the Mn/Sr ratio and delta 18O value are selected to evaluate the representative of the samples on the geochemical information of the sea water. The research shows that the mud microcrystalline limestone is better for the sea water information. Most of the granular limestone, transitional rock and dolomite, to a great extent, preserved the information of the ancient sea water, and the recrystallized limestone is less representative of the information of the ancient sea water, while the salt dissolving breccia - Secondary limestone represents the geochemical information of the epigenetic environment, and its geochemical characteristics have obviously deviated from the characteristics of the ancient sea water. On the basis of detailed diagenetic alteration assessment, the carbon isotope evolution curves of 3 early three fold marine carbonate rocks have been established, and a global and regional comparison is carried out. It shows that the carbon isotope evolution curve has a good global and regional contrast, showing that carbon isotopes of carbonate rocks experienced a number of late Permian early three generations. The oscillations at the different amplitude mainly include the sharp negative migration near the P/T boundary, the three positive drift of the Denerian-Smithian, Smithian-Spathian and Spathian-Anisian boundaries, which together constitute the high frequency of the early three superposition of about 5Myr and the large anomalous carbon cycle evolution pattern. The carbon isotope evolution curve shows that the minimum value of delta ~ (13) C is about -2 per thousand. The maximum value is about 6 per thousand and the amplitude of the oscillation is up to 8 per thousand. The carbon isotope evolution curve of the marine carbonate rock in the study area is well contrasted with the carbon isotope curves of the early three superposition carbonate rocks in the Guizhou beach cutting section, but there are some differences. The peak distribution of carbon isotopes of the early three carbonate rocks in the section of the Guan Dao section is in D At the enerian-Smithian boundary, the peak of 2 sections in the carbon isotope curve we set up in the same period is distributed at the Smithian-Spathian boundary, and the peak value is less than 8 per 1000 in the big Guizhou beach. The abnormal oscillation of the early three fold carbon cycle shows the instability of the early three fold ecological environment and the complexity of the biological resuscitation process. The principle of geostratigraphic stratigraphy has compared the stratigraphic and chronostratigraphy to the strata of the study area. It shows that the Feixianguan formation can be roughly equivalent to the Induan order. The Jijia section can be roughly equivalent to the Smithian order, the Jia two section, the Jijia three and the Jiayan four segments are roughly equivalent to the suborder of the Spathian. The possible driving mechanism of the large amplitude fluctuation of carbon isotopes in the three world carbonate rocks suggests that a single geological event is not sufficient to cause the positive drift and negative drift of the carbon isotopes of the Late Permian early three fold world. The light carbon input to the atmosphere in the Late Permian Siberia dark rock system may cause a negative carbon isotope drift of 1. The negative drift degree of carbon isotopes we observed in carbonate rocks is very far from that of the carbonate rocks we observed, which may be related to the release of methane hydrate triggered by volcanic eruptions. However, the theory of methane hydrate release is difficult to explain this wave pattern for the positive drift and negative drift of the early three superposition of the carbon isotopes of the sea water. This wave pattern may be related to the periodic changes of organic carbon and inorganic carbon burial rates. The positive drift of carbon isotopes in sea water may be related to the increase of organic carbon burial rates. In the early three fold dolomites, there was a higher carbon isotope composition than the adjacent stratigraphic limestone. We quantitatively studied the early three stack sedimentary warm pressure strips on the hand specimen size. The carbon isotope composition of dolomite and associated calcite is different from that of associated calcite, and it is believed that the carbon isotope of dolomite is about 2~2.6 per thousand than that of associated calcite. This result is consistent with the carbon isotope fractionation experiment and theoretical calculation in dolomitization. There is no practical significance for the quantitative study of oxygen isotope differences between dolomite and calcite, but it is certain that dolomite has a higher oxygen isotope composition than associated calcite under the condition of sedimentary temperature and pressure.
【學(xué)位授予單位】：成都理工大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2017
【分類號】：P588.245
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 黃可可;黃思靜;胡作維;鐘怡江;李小寧;;四川盆地宣漢渡口和重慶北碚下三疊統(tǒng)海相碳酸鹽碳同位素組成與演化[J];古地理學(xué)報;2016年01期
2 黃思靜;李小寧;胡作維;劉四兵;黃可可;鐘怡江;;四川盆地東部開江-梁平海槽東西兩側(cè)三疊系飛仙關(guān)組碳酸鹽巖碳氧同位素組成對比及古海洋學(xué)意義[J];地球化學(xué);2016年01期
3 李小寧;黃思靜;胡博;黃可可;黃樹光;陳永梅;;合川鹽井溪嘉陵江組第二段鹽溶角礫巖-次生灰?guī)r的碳氧同位素組成[J];成都理工大學(xué)學(xué)報(自然科學(xué)版);2015年06期
4 陳安清;王立成;姬廣建;曹珂;徐勝林;唐文斌;;川東北早-中三疊世聚鹽環(huán)境及海水濃縮成鉀模式[J];巖石學(xué)報;2015年09期
5 黃春菊;;旋回地層學(xué)和天文年代學(xué)及其在中生代的研究現(xiàn)狀[J];地學(xué)前緣;2014年02期
6 左景勛;童金南;趙來時;常德峰;趙榮軍;;早三疊世下?lián)P子古海洋地球化學(xué)環(huán)境的修復(fù)過程[J];地球科學(xué)(中國地質(zhì)大學(xué)學(xué)報);2013年03期
7 祝幼華;羅輝;蔡華偉;許波;楊昊;趙媛媛;陳迪舒;周志澄;陳金華;;四川廣安謝家槽海相早、中三疊世地層劃分[J];地層學(xué)雜志;2012年04期
8 王起琮;趙淑萍;魏欽廉;肖玲;楊奕華;郭艷琴;牛苗寧;;鄂爾多斯盆地中奧陶統(tǒng)馬家溝組海相碳酸鹽巖儲集層特征[J];古地理學(xué)報;2012年02期
9 胡明毅;魏國齊;李思田;楊威;朱露;楊運(yùn)海;;四川盆地嘉陵江組層序—巖相古地理特征和儲層預(yù)測[J];沉積學(xué)報;2010年06期
10 王一剛;文應(yīng)初;洪海濤;夏茂龍;范毅;文龍;孔令霞;武川紅;;四川盆地北部晚二疊世—早三疊世碳酸鹽巖斜坡相帶沉積特征[J];古地理學(xué)報;2009年02期
相關(guān)博士學(xué)位論文 前3條
1 胡作維;川東北地區(qū)三疊系飛仙關(guān)組白云巖的形成機(jī)制研究[D];成都理工大學(xué);2010年
2 李志強(qiáng);重慶瀝鼻峽背斜煤層氣富集成藏規(guī)律及有利區(qū)帶預(yù)測研究[D];重慶大學(xué);2008年
3 黃先平;川東北地區(qū)下三疊統(tǒng)飛仙關(guān)組儲層綜合研究[D];西南石油學(xué)院;2004年
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