Cenozoic igneous activity in Northern China as a mechanism for late Oligocene climate warming

doi:10.21203/rs.3.rs-1631518/v1

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Cenozoic igneous activity in Northern China as a mechanism for late Oligocene climate warming

https://doi.org/10.21203/rs.3.rs-1631518/v1

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Continental rifting is often associated with important magmatism, which significantly influences the Earth’s climate. In this study, we use comprehensive of 3D seismic and borehole datasets from Northern China to document magma intrusion and associated hydrothermal vent complexes (HTVCs) during the Cenozoic. The aim is to understand their impact on late Oligocene - early Miocene climate. Both Mesozoic and Cenozoic magma intrusions occurred in the Bohai Bay Basin, Northern China, while Cenozoic magmatism in the Bohai Bay Basin occurred during late-Oligocene to early-Miocene, when the final stage of rifting occurred in the region. Methane produced by Cenozoic magma in the Boxing Sag alone is estimated to be 27.2-820 Gt, which accounts for approximately 3-5% of the total methane produced in Northern China (1760-21100 Gt). Our study suggests that warm climate during late Oligocene was potentially subjected to intensive rifting related sill emplacements in basins such as the Bohai Bay Basin. Giving the extensively developed Cenozoic magmatic intrusions in the Bohai Bay Basin, our results suggest that, similarly to the Paleocene-Eocene thermal maximum (PETM), igneous activity during late-Oligocene might played a significant role in driving the Late Oligocene Warming event.

A cooling climate has been documented during the heavily glaciated Antarctic continent during late Oligocene^1,2. However, a late Oligocene warming (LOW) event is recorded at this time as a continuous ~6 ^oC global increase in temperature, as systematically recorded by oxygen and carbon isotopes at multiple locations in the Pacific and Atlantic oceans^1,3-5(Fig. 1a). Although the LOW event has been previously recognized in multiple studies, this ‘enigmatic’ climatic event might have occurred diachronously as proposed by Zachos et al. (2001)⁴. Due to the diachroneity of the LOW climate event, various mechanisms have been proposed for its onset: 1) the Alpine-related Orogenesis⁵, 2) the opening of the South China Sea⁶, 3) climatic warming in the Tibetan Plateau⁷. Unlike the Paleocene/Eocene Thermal Maximum (PETM), which comprises the greatest global warming event recorded in the geological history of this planet, the LOW event remains poorly understood¹.

Magmatic intrusions, and associated extrusion edifices, often generate large volumes of greenhouse gases within what is termed an ‘intrusion aureole system’^8-13. The volume of gases produced by these systems is dependent on a number of factors, including: a) host rock composition, b) total organic content (TOC) in those host rocks, c) intrusion volumes, d) kerogen types of rocks crossed by the magma, and d) magma temperature^9,14-16. Gas produced by magma intrusions are mostly released to the atmosphere via hydrothermal vent complexes (HTVCs), with the timing of these latter complexes often reflecting the main periods of magma intrusion^12-13,17-19. HTVCs can also be reutilized as important fluid flow paths for further fluid migration in sedimentary basins; thus, HTVCs formed during the early magma intrusions can later release significant amounts of gas directly into the atmosphere¹⁸. Volatile components released by HTVCs have played a significant role in driving global climate warming, such as in the cases of the early Jurassic warming⁸, and the well-known PETM⁷. While the intrusion of magma, and associated HTVCs, are regarded as primary mechanisms driving global warming events during continental rifting ^7-8, this mechanism has never been recognized as responsible for the the LOW event, despite the fact that magma-rich continental rifting has occurred during the late Oligocene - early Miocene throughout the globe^20-23.

The Bohai Bay Basin comprises one of the largest Cenozic rift basins in the world, spanning through an area of 200,000 km² (Figs. 1b and DR1)²⁰. Multiple stages of magmatism occurred in the basin from Mesozoic to Cenozoic, with HTVCs becoming widely developed, though seldom documented in the literature. Moreover, geological mapping of sub-surface sills and dikes document 1000 km² of intruded magma in the area of interest to this work (Figs. 1b-1d).

In order to better understand the LOW event, our work presents the first comprehensive mapping of Cenozoic magma intrusions, and associated hydrothermal vent complexes (HTVCs), in the Boxing sag, Bohai Bay Basin, Northern China (Fig. 1d). Previous researches have suggested multiple Cenozoic phases of magma intrusion in the Bohai Bay Basin^24,25. However, a systematic study of Cenozoic magma emplacement is still lacking for the northern Chinese basins. Our study thus present the first data confirming the timing for the Cenozoic magma intrusion based on a comprehensive seismic dataset. Information concerning total organic carbon (TOC) for intruded intervals was combined with the seismic and borehole data to estimate the volumes of greenhouse gases released into the atmosphere via the interpreted intrusions and HTVCs^9,11. The results show that magmatism in the Bohai Bay Basin played a significant role in driving late Oligocene warming. We further postulate that continental rifting might be a prevalent mechanism driving global warming on Earth, as recorded by the Early Jurassic Warming⁸, the PETM⁷, and the LOW event considered in this study.

Magma intrusions and hydrothermal vent complexes

Igneous sills are characterized by their high-amplitude and positive reflections in seismic data^26-29. They often reveal abrupt terminations and saucer-shaped geometries^13,30 (Fig. 2). Previous studies have documented magma intrusions throughout Cenozoic strata in the seven sub-basins of the Bohai Bay Basin, Northern China²⁴ (Fig. 1b). A few of these studies have also recognized vertically acoustic transparent zones in seismic data in the Bozhong sub-basin (Fig. 1b), namely volcanic conduits closely associated with regional intrusions³¹.

Seismic data show that igneous sills are predominantly developed in the western part of the Boxing sag within Paleocene to Miocene strata (Fig. 2). The total area covered by sill exceeds 1000 km² in the Boxing sag (Figs. 1b and 1c). However, due to the fact that sills were able to intrude multiple stratigraphic units, the actual area intruded by magma in the Boxing sag is likely 1.5 to 2 times larger than the area of 1000 km² recognized in seismic data (Fig. 2). Intrusions with thicknesses (and volumes) below seismic resolution are recognized in the Bohai Bay Basin as forming meter- to tens-of-meter thick igneous bodies²⁵. Some of the layer-parallel strong reflections were confirmed as intruded basalt of tens meters by well drilling in the study area (Fig. 2)

Igneous intrusions in the Boxing sag follow a E-W strike, which is consistent with structural trends in the Jiyang sub-basin, Bohai Bay Basin (Figs. 1b and 1c). Sills in the Boxing sag have diameters up to 7 km (Fig. 2a), and their depths of intrusion range from 4000 m to a few hundred meters below the surface (Fig. 2). Most of the interpreted sills are saucer-shaped, with their tips intruding across multiple strata reflectors (Fig. 2). A p-wave velocity of 5.5 km/s is used in this study to determine the resolution limit for the detection of igenous sills^33,34. With a dominant frequency of 10 Hz, the interpreted sills show a minimum thickness of 100 m in the Boxing sag.

Chimney-like reflections identified in seismic data represent hydrothermal vent complexes, or HTVCs (Fig. 2). In the Boxing sag, these HTVCs show common crater-, eye-, and dome-shaped geometries (Fig. 2). Their diameters range from 200 m to more than 1700 m, and their heights from 400 m to 2500 m (Table 1). The sills in the Boxing sag are thus smaller than those along the north Atlantic margin¹³. Conversely, the height of HTVCs in the Boxing sag are significantly larger than in the north Atlantic margin^13,18,35,36.

In the Boxing sag, the top of the HTVCs is onlapped by horizon T1, a seismic-stratigraphic marker representing the end of continental rifting in the Bohai Bay Basin (Fig. 2, and DR2). A total of 70 HTVCs were identified in the Boxing sag (Fig. 1d). However, more HTVCs with sizes below minimum seismic resolution should occur in the interpreted 3D volume. Volcanic edifices often have similar shapes to those of the HTVCs. However, as shown in Reynolds et al., (2017), volcanic edifices often have larger sizes than the HTVCs documented in this study. HTVCs are also closely associated with the interpreted sills, and are often developed at the tips of the sill intrusions, or at where the sills cross the host strata^13,36.

Timings for the formation of sill emplacements and associated HTVCs

The relative ages for sill emplacements and associated HTVCs were constrained by understanding the relationships between sills-HTVCs features and stratigraphic units of known ages, due to the lack of borehole data sampling the sills^13,14,17,19. Previous work indicate that multiple phases of igneous intrusions occurred in the Bohai Bay Basin, with magmatism during early continental rifting being the most intense²⁴. A wide range of ages were suggested for igneous rocks in the Bohai Bay Basin, extending from 70 Ma to 1.3 Ma²⁴. However, as indicated by Jolley et al., (2002), ages provided by radiometric dating methods are often erroneous, yielding discrepancies of several million years, and the timing of sill emplacements in the Bohai Bay Basin is still not accurate. A seismic-based technique, which is known to offer independent constraints for the relative timings of sill emplacement, has been used in the published literature^17,28,37. The seismic-based technique uses post-intrusion sediment distribution and onlap relationships onto forced folds formed above igneous sills to constrain the timing of sill intrusion³⁸. The timing and duration of sill intrusions were thus seismically constrained in this work by the upper boundaries of the intrusion-related vent structures^9,36,39.

In the Boxing sag, sills intruded multiple stratigraphic units, and such a character is often being misinterpreted as reflecting their intrusion as synchronous to the strata in which they occur. HTVCs associated with igneous sills indicate that, though the magma intrusions occurred in distinct units (Fig. 2), the timing for their emplacement is the same. The interpreted data confirm that horizon T1 onlaps all the interpreted HTVCs, constraining sill intrusion and HTVCs to an age of c. 24.6 Ma (Figs. 2 and DR2). Magma intrusion during the post-rift stage, and associated HTVCs, were also documented in the Boxing sag (Fig. 2d), a character beyond the scope of this work.

Thermogenic methane release from interpreted sills and HTVCs

Our research follows the method by Svensen et al. (2004)⁹ in which the volume of methane produced during contact metamorphism is calculated as:

W_CH4 = 1.34F_CV_A^.ρ (1)

where 1.34 represents an atomic-weight conversion factor between carbon and methane, F_C is equal to the TOC content of the host rocks, V_A is the volume of the aureole and ρ is rock density, assumed as 2400 kg/m³ in the study area.

With the method of Svensen et al. (2004)⁹, host rock properties (TOC content) greatly affect the volume of gas produced during metamorphism. In this research, we used 386 TOC data points from sill-intruded Paleogene strata (Fig. DR3). Our data reveal that TOC values for Paleogene strata in the Boxing sag range from 0.04% to 6%, with 298 TOC data points (77.2%) between 0.5% to 3%, giving is an average TOC value of 1.84%.

In the Boxing sag, the thickness of seismically resolved sills is greater than 50 m (Fig. 2). Previous research indicate that thickness of igneous rocks in the Jiyang sub-basin, mostly located in the Boxing sag, can reach > 200 m²⁵. In our estimates of V_A,we assume an aureole thickness of 100-400 m in the Boxing sag, with one sill thickness above and below the intrusion^9,15. As illustrated in previous section, the area covered by sills is 1000 km² in the Boxing sag, and due to the fact that sill emplacement occurred in various stratigraphic units the depth-independent, cumulative area covered by sills is estimated to vary from 1500 km² to 2000 km².

Based on these assumptions, our calculation in the Boxing sag alone indicate 0.32-9.65*10¹⁷ g of gas produced during the Paleogene (Fig. 3). Given the average TOC values of Paleogene strata is 1.84% in the Boxing sag, a value of 1.18-4.73*10¹⁷ g of gas is considered to be more plausible (Fig. 3). In order to further extend our evaluation to the entire Bohai Bay Basin, we collected 325 TOC data points for Paleogene strata in the Jiyang sub-basin. The data show that 277 data points (85%) range between 0.5% to 4%, corresponding to average TOC values of 2.7% (Fig. DR3). The cumulative area covered by sills in the Boxing sag accounts for c. 9% of the total area covered by igneous rocks, as indicated by Jin et al. (2012)²⁵. We stress that TOC values for Paleogene strata in the Boxing sag are some of the lowest in the Bohai Bay Basin, estimations of methane being released should be significantly larger than an estimation using 1.84% as assumed in the Boxing sag. The thickness of sills in the Boxing sag was estimated to range between 50-200 m. However, other sub-basins with sills show that they may reach 1300 m in thickness, such as in the Liaohe and Bozhong sub-basins²⁵. The sills in these two sub-basins accounts for > 50% of the cumulative area covered by sills in the Bohai Bay Basin. Based on these data, we estimate that methane generated in the whole Bohai Bay Basin reached values of 3.54-42.8*10¹⁸ g (Fig. 3).

Mechanisms driving climatic warming during late Oligocene-early Miocene

The Oligocene Epoch (34-23 Ma) was a time of continental-scale Antarctic glaciations, reflecting cooling climatic conditions, as documented by δ¹⁸O from deep-sea records at various locations around the world, e.g., DSDP Site 573; ODP Sites 689, 690, 748, 925, 1218; and IODP Sites U1356 and U1404^1-4,40-44. However, the Antarctic ice sheet waxed and waned during the late Oligocene, initiating a warming climatic period in a relatively low CO₂ world, as proven by sea-surface temperature (SST) records¹. The term Late Oligocene Warming, or LOW, represents a period of climatic warming during a heavily glaciated Antarctic world, spanning from ~26.5 Ma to 24.5 Ma, in which SST records at the highest latitude indicate a 1-2 ^oC warming¹ (Fig. 1a). Oxygen and carbon isotopic data acquired in marine deposits from the Pacific and Atlantic oceans indicate a sustained warming of ~6 °C during the LOW^4,5.

Despite the fact this LOW event is documented throughout the world, the mechanisms that drove this warming event remain partly understood^1,5. Plausible mechanisms include mountain building, reconfigurations in oceanic gateways, and orbital forcing^3-7. A very important mechanism driving climate warming, extrusive and intrusive igneous activity, is also suggested as a main cause of past global warming, such as during the early Jurassic warming and the well-known PETM^{8,9,13,15,45-47}. However, this mechanism is seldom being documented in literature to be one of the mechanisms for the LOW event, despite that more than six episodes of major climatic and environmental perturbations throughout geological history were correlated with the formation of Large Igneous Provinces (LIPs) such as the Permo-Triassic Extinction Event (~ 251 Ma), the Toarcian Oceanic Anoxic Event (~ 183 Ma), and in the early Eocene climatic optimum (~ 55 Ma)^9,13,48-51.

Our first results show that horizon T1, marking the Oligocene-Miocene stratigraphic boundary in the Bohai Bay Basin (24.6 Ma), was when sills were intruded and associated HTVCs formed (Fig. 2). Previous research on the timing(s) of sill intrusion indicate various phases of igneous activity in the Bohai Bay Basin since the Paleocene²⁴. However, the scales of these multiple phases of igneous activity are not clear in the published literature as: 1) research in the Bohai Bay Basin has thus far been driven by hydrothermal exploration and understanding the areas with most igneous rocks, not the timing of their formation, were prioritised^24,25; 2) though thousands of wells were drilled throughout the Bohai Bay Basin, interest in characterizing igneous-related reservoirs started only very recently; thus igneous samples have been seldom collected and dated in the study area; 3) current radiometric dating methods for igneous rocks are often uncertain, yielding age discrepancies of several million years^17,28,37,38, and 4) a lack of a large database on the age of igneous rocks in the Bohai Bay Basin make it difficult to discriminate between different phases of igneous activity. In our research, the seismic-based technique of identifying onlap relationships amongst strata, sills and their associated HTVCs, offers the best results to understand the timings of sill intrusion³⁸.

Studies indicate that igneous activity was most intense at the start of continental rifting and during rift stage 3 (Fig. DR2). However, our results on the timings of sill intrusion in the Boxing sag indicate that, the end of rifting (horizon T1) was the most intensive period of igneous activity. Research on igneous activities in the Bozhong sub-basin (Fig. 1) by Zhu et al., (2020)³¹ also confirms that igneous activity at the end of the continental rifting stage was stronger than during other phases³¹. Thermal models also indicate that the Bohai Bay Basin changed from weak extension during the Oligocene to marked extension during the late-Oligocene-early Miocene (Fig. 4)⁵².

Heat flow in the Bozhong and Liaohe sub-basins, the largest areas with Cenozoic igneous rocks in the Bohai Bay Basin, peaked at c. 24.6 Ma⁵³. In the Jiyang sub-basin, where the Boxing sag is located, heat flow reached a value at c. 36 Ma that is close to the peak value at c. 24.6 Ma⁵³. Heat flow models indicate that late-Oligocene-early Miocene may have represented a time of increased mantle activity, consistent with our observation that sill intrusion was widespread in the Boxing sag at ~24.6 Ma.

HTVCs are postulated to form within 10s of years of sill intrusion^12,54, and HTVCs in the Boxing sag were formed in close temporal proximity to the LOW occurring at ~26.5 - 24.5 Ma^1,4,5. Our estimation of gas produced as a result of magma intrusion in the Boxing sag ranges from 0.32-9.65*10¹⁷g (27.2- 820 Gt of methane given a 85% of transfer rate), to 1.18-4.73*10¹⁷g (100-400 Gt of methane) considering an average TOC value of 1.84 (wt %) (Fig. 3). A very important parameter is TOC content in Paleogene strata within the Boxing sag, which is significantly lower than in other areas of the Bohai Bay Basin. This allows us to estimate the methane volumes for the entire Bohai Bay Basin. Based on the geological data in this work, we estimate that 30-50 times of gas being produced in the entire Bohai Bay Basin, reaching values of 3.54-42.8*10¹⁸ g (3000-36000 Gt of methane given a transfer rate of 85% of organic carbon).

Kerogen type comprises another important factor that controls the transfer rate of organic carbon to methane^8,9,16. Models indicate that a 50 wt % TOC transfer rate is applicable for type Ⅱ kerogen^8,16, as in the case of the Boxing sag. Our estimation of methane produced by magma intrusions in the Bohai Bay Basin is thus reduced to 1760-21100 Gt (Fig. 3). Our estimation is deemed conservative since the weight conversion factor between carbon and methane (F_C) used in Equation 1 has a minimum value of 1.34 - F_C values of 1.5-5 were used in other published estimates⁸. Furthermore, kerogen types with a have higher transfer rate of organic carbon to methane were widely developed throughout the Bohai Bay Basin, and a lowermost transfer rate of 50 wt % is used in our estimation¹⁶. Finally, possible contribution by magma degassing, or shallow gas reservoirs pierced by the hydrothermal vent complexes are not considered in our estimation⁹.

For the well-known PETM, 300-3500 Gt of methane were previously calculated in the Vøring and Møre Basins, a fraction of the 1500-17500 Gt of methane produced in the North Atlantic Volcanic Province (NAVP) that triggered the PETM^9,12(Fig. 3). An estimation of 27,400 Gt of methane produced in the Karoo Basin was postulated to have triggered the early Jurassic Warming event⁸(Fig. 3). Our estimation of methane produced by magma intrusion in the Bohai Bay Basin ranges from 1,760 to 21,100 Gt, a value that is compatible to that of the NAVP and in the Karoo Basin, one of the main events considered to have triggered the LOW⁹.

Studies show that global warming events are often temporally linked to the formation of Large Igneous Provinces (LIPs)¹⁶. However, despite the wide distribution of Cenozoic igneous rocks in the Bohai Bay Basin, Northern China, the study area is not a LIP. Our research further propose that not only basins affected by LIPs, but also basins with significant magmatism, such as the Bohai Bay Basin, could have driven global warming events. While most climatic records of past warming events are gathered from marine basins at present, this work shows that one should also focus on onshore areas, which have the advantage of containing vast borehole databases and sediment samples.

Seismic data and interpretation

Seismic data from the Boxing sag, Dongying depression, Jiyang sub-basin, Bohai Bay Basin, were interpreted in this study (Figs. 1 and 2). The seismic data were provided by the Shengli Oilfield, Sinopec. Interpreted 3D seismic data from the Boxing Sag covers an area of 1800 km², with a sampling interval of 2 ms and a bin spacing of 25 x 25 m. Showing a dominant frequency of 40 Hz, vertical resolution in the seismic volume can reach 20 m near the surface and 40 m at the depth of the magma intrusions investigated in this work. Seismic interpretation was completed using Schlumberger’s Petrel^®. Interpretation of the horizons in the study follow the interpretation framework of the Shengli Oilfield, Sinopec. The relative ages of the interpreted seismic units were also correlated by the published literature^55,56, and are consistent with the stratigraphic framework of Sinopec’s Exploration and Production Research Institute. Key stratigraphic markers include: 1) a Paleocene and Eocene interface (T8) marking the boundary between syn-rift stages 1 and 2; 2) the top of the Es3 member (T4), which marks the top of main source rock intervals in the study area; and 3) the Oligocene-Miocene boundary (horizon T1), a regional unconformity marking the end of syn-rift tectonics in the study area²⁰ (Fisg. 2 and DR2).

VSP profile

A VSP profile for well T719 is used in this study to calculate the heights of the HTVCs (Fig. DR4).

TOC values

The TOC data used in this study were provided by the Shengli Oilfield, Sinopec. Some of the TOC data were measured at China University of Geosciences (Wuhan) under past projects supported by the Shengli Oilfield, Sinopec (Fig. DR3).

Gas and methane calculations

Gas and methane released by magma intrusions (aureoles) were calculated using the methods proposed by Svensen et al. (2004)⁹. Constraints on kerogen type were taken into account following the modeling work of Iyer er al. (2017)¹⁶. Thickness data for other areas of the Bohai Bay Basin, other than the Boxing sag, are taken from Jin et al. (2012)²⁵.

Data availability

The data that support the findings of this study are available within the Supplementary Information.

Acknowledgements

The Shengli Oil Field, Sinopec is acknowledged for the seismic, well, and TOC data used in this research. Schlumberger is acknowledged for the provision of data interpretation software. The authors acknowledge funding from the National Natural Science Foundation of China (Project No. U20B6001, and No. 41902198, ) and the China postdoctoral Science foundation (Project No. 2019M662738).

Author contributions

Z.T. conducted the interpretation and analyses, and wrote the original draft; Z.H., Q.L., Z.T., and X.G. lead the funding acquisition, revised part of the manuscript, and jointly discussed the interpretation and results with Y.H.. T.M.A. revised the manuscript, and suggested for further improvement of the figures and writing. Z.H. and T.M.A. participated in all stages of paper revisions.

Competing interests

The authors declare no competing interests.

Materials & Correspondence

Dr. Ze Tao and Prof. Xiaowen Guo are the correspondences, and material requests should be addressed

[1] O’BRIEN, C. L., HUBER, M., THOMAS, E., PAGANI, M., SUPER, J. R., ELDER, L. E. & HULL, P. M. 2020. The enigma of Oligocene climate and global surface temperature evolution. Proceedings of the National Academy of Sciences, 117, 25302-25309.

[2] HAUPTVOGEL, D. W., PEKAR, S. F. & PINCAY, V. 2017. Evidence for a heavily glaciated Antarctica during the late Oligocene “warming” (27.8–24.5 Ma): Stable isotope records from ODP Site 690. Paleoceanography, 32, 384-396.

[3] DE MAN, E. & VAN SIMAEYS, S. 2004. Late Oligocene Warming Event in the southern North Sea Basin: benthic foraminifera as paleotemperature proxies. Netherlands Journal of Geosciences, 83, 227-239.

[4] ZACHOS, J., PAGANI, M., SLOAN, L., THOMAS, E. & BILLUPS, K. 2001. Trends, Rhythms, and Aberrations in Global Climate 65 Ma to Present. Science, 292, 686-693.

[5] SCHLUNEGGER, F. & NORTON, K. P. 2015. Climate vs. tectonics: the competing roles of Late Oligocene warming and Alpine orogenesis in constructing alluvial megafan sequences in the North Alpine foreland basin. Basin Research, 27, 230-245.

[6] SUN, Q., ALVES, T. M., ZHAO, M., SIBUET, J.-C., CALVèS, G. & XIE, X. 2020. Post-rift magmatism on the northern South China Sea margin. GSA Bulletin, 132, 2382-2396.

[7] WU, F., MIAO, Y., MENG, Q., FANG, X. & SUN, J. 2019. Late Oligocene Tibetan Plateau Warming and Humidity: Evidence From a Sporopollen Record. Geochemistry, Geophysics, Geosystems, 20, 434-441.

[8] SVENSEN, H., PLANKE, S., CHEVALLIER, L., MALTHE-SøRENSSEN, A., CORFU, F. & JAMTVEIT, B. 2007. Hydrothermal venting of greenhouse gases triggering Early Jurassic global warming. Earth and Planetary Science Letters, 256, 554-566.

[9] SVENSEN, H., PLANKE, S., MALTHE-SøRENSSEN, A., JAMTVEIT, B., MYKLEBUST, R., RASMUSSEN EIDEM, T. & REY, S. S. 2004. Release of methane from a volcanic basin as a mechanism for initial Eocene global warming. Nature, 429, 542-545.

[10] AARNES, I., FRISTAD, K., PLANKE, S. & SVENSEN, H. 2011. The impact of host-rock composition on devolatilization of sedimentary rocks during contact metamorphism around mafic sheet intrusions. Geochemistry, Geophysics, Geosystems, 12.

[11] AARNES, I., PLANKE, S., TRULSVIK, M. & SVENSEN, H. 2015. Contact metamorphism and thermogenic gas generation in the Vøring and Møre basins, offshore Norway, during the Paleocene–Eocene thermal maximum. Journal of the Geological Society, 172, 588-598.

[12] AARNES, I., SVENSEN, H., CONNOLLY, J. A. D. & PODLADCHIKOV, Y. Y. 2010. How contact metamorphism can trigger global climate changes: Modeling gas generation around igneous sills in sedimentary basins. Geochimica et Cosmochimica Acta, 74, 7179-7195.

[13] REYNOLDS, P., PLANKE, S., MILLETT, J. M., JERRAM, D. A., TRULSVIK, M., SCHOFIELD, N. & MYKLEBUST, R. 2017. Hydrothermal vent complexes offshore Northeast Greenland: A potential role in driving the PETM. Earth and Planetary Science Letters, 467, 72-78.

[14] SYDNES, M., FJELDSKAAR, W., LøTVEIT, I. F., GRUNNALEITE, I. & CARDOZO, N. 2018. The importance of sill thickness and timing of sill emplacement on hydrocarbon maturation. Marine and Petroleum Geology, 89, 500-514.

[15] IYER, K., RüPKE, L. & GALERNE, C. Y. 2013. Modeling fluid flow in sedimentary basins with sill intrusions: Implications for hydrothermal venting and climate change. Geochemistry, Geophysics, Geosystems, 14, 5244-5262.

[16] IYER, K., SCHMID, D. W., PLANKE, S. & MILLETT, J. 2017. Modelling hydrothermal venting in volcanic sedimentary basins: Impact on hydrocarbon maturation and paleoclimate. Earth and Planetary Science Letters, 467, 30-42.

[17] ZHAO, F., BERNDT, C., ALVES, T. M., XIA, S., LI, L., MI, L. & FAN, C. 2021. Widespread hydrothermal vents and associated volcanism record prolonged Cenozoic magmatism in the South China Sea. GSA Bulletin, 133, 2645-2660.

[18] ROELOFSE, C., ALVES, T. M. & OMOSANYA, K. D. O. 2021. Reutilisation of hydrothermal vent complexes for focused fluid flow on continental margins (Modgunn Arch, Norwegian Sea). Basin Research, 33, 1111-1134.

[19] MØLLER HANSEN, D. 2006. The morphology of intrusion-related vent structures and their implications for constraining the timing of intrusive events along the NE Atlantic margin. Journal of the Geological Society, 163, 789-800.

[20] TAO, Z., HE, Z., ALVES, T. M., GUO, X., GAO, J., HE, S. & ZHAO, W. 2022. Structural inheritance and its control on overpressure preservation in mature sedimentary basins (Dongying depression, Bohai Bay Basin, China). Marine and Petroleum Geology, 137, 105504.

[21] WANG, P., LI, S., SUO, Y., GUO, L., SANTOSH, M., LI, X., WANG, G., JIANG, Z., LIU, B., ZHOU, J., JIANG, S., CAO, X. & LIU, Z. 2021. Structural and kinematic analysis of Cenozoic rift basins in South China Sea: A synthesis. Earth-Science Reviews, 216, 103522.

[22] PETERSEN, H. I., NYTOFT, H. P., RATANASTHIEN, B. & FOOPATTHANAKAMOL, A. 2007. OILS FROM CENOZOIC RIFT-BASINS IN CENTRAL AND NORTHERN THAILAND: SOURCE AND THERMAL MATURITY. Journal of Petroleum Geology, 30, 59-78.

[23] TIERCELIN, J.-J. 1991. Natural Resources in the Lacustrine Facies of the Cenozoic Rift Basins of East Africa. Lacustrine Facies Analysis.

[24] MAO X., LUO L., WANG X. & GUO D. 2020. Distribution Characteristics of Cenozoic Volcanic Rocks and Its Geothermal Exploration Potential in Bohai Bay Basin. Geoscience, 2020, 34( 4), 858-864.

[25] JIN C., QIAO D. & DAN W. 2012. Meso-Cenozoic volcanic rock distribution and reservoir characteristics in the Bohai Bay Basin. Oil & Gas Geology, 33(1), 19-36.

[26] CARTWRIGHT, J. & MøLLER HANSEN, D. 2006. Magma transport through the crust via interconnected sill complexes. Geology, 34, 929-932.

[27] MAGEE, C., HUNT-STEWART, E. & JACKSON, C. A. L. 2013. Volcano growth mechanisms and the role of sub-volcanic intrusions: Insights from 2D seismic reflection data. Earth and Planetary Science Letters, 373, 41-53.

[28] HANSEN, D. M. & CARTWRIGHT, J. 2006. The three-dimensional geometry and growth of forced folds above saucer-shaped igneous sills. Journal of Structural Geology, 28, 1520-1535.

[29] ROCCHI, S., MAZZOTTI, A., MARRONI, M., PANDOLFI, L., COSTANTINI, P., GIUSEPPE, B., BIASE, D. D., FEDERICI, F. & Lô, P. G. 2007. Detection of Miocene saucer-shaped sills (offshore Senegal) via integrated interpretation of seismic, magnetic and gravity data. Terra Nova, 19, 232-239.

[30] SIREGAR, E., OMOSANYA, K. O., MAGEE, C. & JOHANSEN, S. E. 2019. Impacts of fault-sill interactions on sill emplacement in the Vøring Basin, Norwegian North Sea. Journal of Structural Geology, 126, 156-174.

[31] ZHU, H., ZENG, Z., ZENG, H. & XU, C. 2020. 3D seismic data attribute-based characterization of volcanic reservoirs in the BZ34-9 Block, Bohai Bay Basin, eastern China. GEOPHYSICS, 85, IM1-IM13.

[32] WANG, L., SUN, Z., YANG, J., SUN, Z., ZHU, J., ZHUO, H. & STOCK, J. 2019. Seismic characteristics and evolution of post-rift igneous complexes and hydrothermal vents in the Lingshui sag (Qiongdongnan basin), northwestern South China Sea. Marine Geology, 418, 106043.

[33] Skogly, O., 1998. Seismic Characterization and Emplacement of Intrusives in the Vøring Basin. Cand Scient thesis. Department of Geology, University of Oslo.

[34] BERNDT, C., SKOGLY, O. P., PLANKE, S., ELDHOLM, O. & MJELDE, R. 2000. High-velocity breakup-related sills in the Vøring Basin, off Norway. Journal of Geophysical Research: Solid Earth, 105, 28443-28454.

[35] OMOSANYA, K. O., MAIA, A. R. & ERUTEYA, O. E. 2020. Seismic, morphologic and scale variabilities of subsurface pipes and vent complexes in a magma-rich margin. Bulletin of Volcanology, 82, 40.

[36] Planke, S., Rasmussen, T., Rey, S. S., & Myklebust, R. (2005).Seismic characteristics and distribution of volcanic intrusions and hydrothermal vent complexes in the Vøring and Møre basins.In A. G. Doré, & B. A. Vining (Eds.), Petroleum Geology: North-West Europe and Global Perspectives - Proceedings of the 6th Petroluem Geology Conference (pp. 833–844). London: Geological Society.

[37] JOLLEY, D. W., CLARKE, B. & KELLEY, S. 2002. Paleogene time scale miscalibration: Evidence from the dating of the North Atlantic igneous province. Geology, 30, 7-10.

[38] TRUDE, J., CARTWRIGHT, J., DAVIES, R. J. & SMALLWOOD, J. 2003. New technique for dating igneous sills. Geology, 31, 813-816.

[39] DAVIES, R., BELL, B. R., CARTWRIGHT, J. A. & SHOULDERS, S. 2002. Three-dimensional seismic imaging of Paleogene dike-fed submarine volcanoes from the northeast Atlantic margin. Geology, 30, 223-226.

[40] VILLA, G. & PERSICO, D. 2006. Late Oligocene climatic changes: Evidence from calcareous nannofossils at Kerguelen Plateau Site 748 (Southern Ocean). Palaeogeography, Palaeoclimatology, Palaeoecology, 231, 110-119.

[41] MILLER, K. G., FAIRBANKS, R. G. & MOUNTAIN, G. S. 1987. Tertiary oxygen isotope synthesis, sea level history, and continental margin erosion. Paleoceanography, 2, 1-19.

[42] ZANAZZI, A., KOHN, M. J., MACFADDEN, B. J. & TERRY, D. O. 2007. Large temperature drop across the Eocene–Oligocene transition in central North America. Nature, 445, 639-642.

[43] PäLIKE, H., NORRIS, R. D., HERRLE, J. O., WILSON, P. A., COXALL, H. K., LEAR, C. H., SHACKLETON, N. J., TRIPATI, A. K. & WADE, B. S. 2006. The Heartbeat of the Oligocene Climate System. Science, 314, 1894-1898.

[44] PEKAR, S. F., DECONTO, R. M. & HARWOOD, D. M. 2006. Resolving a late Oligocene conundrum: Deep-sea warming and Antarctic glaciation. Palaeogeography, Palaeoclimatology, Palaeoecology, 231, 29-40.

[45] BAINS, S., CORFIELD, R. M. & NORRIS, R. D. 1999. Mechanisms of Climate Warming at the End of the Paleocene. Science, 285, 724-727.

[46] KENDER, S., BOGUS, K., PEDERSEN, G. K., DYBKJæR, K., MATHER, T. A., MARIANI, E., RIDGWELL, A., RIDING, J. B., WAGNER, T., HESSELBO, S. P. & LENG, M. J. 2021. Paleocene/Eocene carbon feedbacks triggered by volcanic activity. Nature Communications, 12, 5186.

[47] WRIGHT, J. D. & SCHALLER, M. F. 2013. Evidence for a rapid release of carbon at the Paleocene-Eocene thermal maximum. Proceedings of the National Academy of Sciences, 110, 15908-15913.

[48] DICKENS, G. R., O'NEIL, J. R., REA, D. K. & OWEN, R. M. 1995. Dissociation of oceanic methane hydrate as a cause of the carbon isotope excursion at the end of the Paleocene. Paleoceanography, 10, 965-971.

[49] KEMP, D. B., COE, A. L., COHEN, A. S. & SCHWARK, L. 2005. Astronomical pacing of methane release in the Early Jurassic period. Nature, 437, 396-399.

[50] ZACHOS JAMES, C., RöHL, U., SCHELLENBERG STEPHEN, A., SLUIJS, A., HODELL DAVID, A., KELLY DANIEL, C., THOMAS, E., NICOLO, M., RAFFI, I., LOURENS LUCAS, J., MCCARREN, H. & KROON, D. 2005. Rapid Acidification of the Ocean During the Paleocene-Eocene Thermal Maximum. Science, 308, 1611-1615.

[51] WIGNALL, P. B. 2001. Large igneous provinces and mass extinctions. Earth-Science Reviews, 53, 1-33.

[52] LIU, Q., HE, L. & CHEN, L. 2018. Tectono-thermal modeling of Cenozoic multiple rift episodes in the Bohai Bay Basin, eastern China and its geodynamic implications. International Journal of Earth Sciences, 107, 53-69.

[53] LIU QiongYing, HE LiJuan. 2019. Tectono-thermal modeling of the Bohai Bay Basin since the Cenozoic. Chinese Journal of Geophysics (in Chinese), 62(1): 219-235.

[54] Jamtveit, B., Svensen, H., Podladchikov, Y.Y., Planke, S., 2004. Hydrothermal vent complexes associated with sill intrusions in sedimentary basins. Physical Geology of High-Level Magmatic Systems, 234, 233–241.

[55] S. Li, G. Zhao, L. Dai, L. Zhou, X. Liu, Y. Suo, M. Santosh, 2012. Cenozoic faulting of the Bohai Bay Basin and its bearing on the destruction of the eastern North China Craton Journal of Asian Earth Sciences, 47, pp. 80-93.

[56] J. Su, W. Zhu, J. Wei, L. Xu, Y. Yang, Z. Wang, Z. Zhang, 2011. Fault growth and linkage: implications for tectonosedimentary evolution in the Chezhen basin of Bohai Bay, eastern China AAPG Bulletin, 95, pp. 1-26.

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Cenozoic igneous activity in Northern China as a mechanism for late Oligocene climate warming

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