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Late Paleozoic deglaciation is the first icehouse‐to‐greenhouse transition in a world with expansive tropical forests, but the detailed process of this climatic upheaval is still debated due to lack of high‐precision global correlation. Here, based on the cyclostratigraphic analysis of a deep‐marine succession of Naqing in South China, chronostratigraphic correlation was achieved between Paleo‐Tethyan deep‐marine carbonate cyclicity and U‐Pb zircon age‐calibrated cyclothems from the Pangaean paleotropics. Refining the global chronostratigraphy indicates ages of 294.1 ± 0.2 Ma and 290.1 ± 0.2 Ma for the base of the Sakmarian and Artinskian stages, respectively. We juxtapose the climatic proxies and indicators across blocks and latitudes to decipher the trends and rhythms in climate change during a period from the apex of the Late Paleozoic ice age (LPIA) to the initial deglaciation. On the multiple‐million‐year time scale, the polar and equatorial climates were linked through the atmospheric pCO2 control. A rise in pCO2 promoted Gondwanan deglaciation and tropical aridification. The disparity in the inferred polarity of tropical climate changes during glacials and interglacials has been confirmed on the million‐year time scale. The meridional flux of moisture was enhanced during the minima of the ∼1.2 Myr obliquity cycle, periodically resulting in Gondwanan glaciation, glacio‐eustatic sea‐level lowerings, and reduced moisture availability in the tropical Pangaean and Paleo‐Tethyan regions. Our study provides an improved temporal resolution and understanding of the apex of the LPIA. Plain Language Summary: Cyclostratigraphic analysis of the Naqing section in South China indicates ages of 294.1 ± 0.2 Ma and 290.1 ± 0.2 Ma for the base of the Sakmarian and Artinskian stages, respectively. The marine and terrestrial records across continents were synchronized using a high‐resolution global correlation. The result indicates that the climatic changes were mainly in pace with 1.2 Myr obliquity cycles superimposed on long‐term Gondwana deglaciation and tropical aridification associated with an increase of pCO2 levels. These results reinforce a solid linkage between climate changes at low and high latitudes, regardless of the ice‐sheet volume. Key Points: Chronostratigraphy of Asselian and Sakmarian stages was refined by cyclostratigraphic analysis on a deep‐marine succession in South ChinaThe rise in atmospheric pCO2 promoted Gondwanan deglaciation and tropical aridificationObliquity nodes resulted in the Gondwanan glaciation, glacio‐eustatic sea‐level lowerings, and decrease of tropical moisture availability [ABSTRACT FROM AUTHOR]

The timing and location India–Asia collision is crucial to understanding the evolution of the Himalayan–Tibetan orogen and global climate change; however, estimates of the timing of the India–Asia collision and the size of Greater India remain highly controversial. We report here the first reliable early Eocene paleomagnetic results from the Zhepure Formation limestone in the Tethyan Himalaya (TH). Both positive fold and reversal tests indicate a primary origin. The tilt‐corrected site‐mean direction is Ds = 332.6°, Is = 20.1°, ks = 90.9, α95 = 2.8° (N = 30). The site‐mean inclination increased from 20.1° to 27.5° after inclination shallowing correction, yielding a paleopole at 61.2°N, 337.3°E, A95 = 2.6° and a corresponding paleolatitude of 15.2° ± 2.6°N for the reference point (29.5°N, 91.0°E). Our new paleomagnetic results, together with the reliable Cretaceous to Paleogene paleomagnetic results from the TH, Lhasa terrane and Indian craton, suggest that there was ∼900–1,140 km north‐south crustal shortening occurred between the TH and the Indian craton, and that India collided with Asia at no later than ∼51–49.5 Ma. Plain Language Summary: The India–Asia collision is among the most intriguing topics in earth sciences because of its influence on global climate and Cenozoic topography. However, several questions still remain unanswered, such as: how big was Greater India? When, where, and how did the India collide with Asia? We report the first reliable early Eocene paleopole from the TH and assess the timing of the India–Asia collision and the size of Greater India. Our results suggest a relatively small Greater India, and that India collided with Asia at no later than ∼51–49.5 Ma. The constraints on the India–Asia collision indicated by our data provide new boundary conditions for the history of the Himalayan–Tibetan orogen and global climate change. Key Points: The Tethyan Himalaya (TH) was located at 15.2° ± 2.6°N at ∼51–49.5 MaThere was ∼900–1,140 km north‐south crustal shortening occurred between the TH and the Indian cratonIndia collided with Asia at no later than ∼51–49.5 Ma [ABSTRACT FROM AUTHOR]

At the end of the Late Paleozoic Ice Age (LPIA) from late Early Permian to early Late Permian, the global climate was impacted by a prevailing megamonsoon and Gondwanan deglaciation. To better understand the abiotic and biotic responses to Milankovitch-forced climate changes during this time period, multi-element X-ray fluorescence (XRF) geochemistry analyses were conducted on 948 samples from the late Early−late Middle Permian Maokou Formation at Shangsi, South China. The Fe/Ti, S/Ti, Ba/Ti and Ca time series, which were calibrated with an existing “floating” astronomical time scale (ATS), show the entire suite of Milankovitch rhythms including 405 kyr long eccentricity, 128 and 95 kyr short eccentricity, 33 kyr obliquity and 20 kyr precession. Spectral coherency and cross-phase analysis reveals that chemical weathering (monitored by Fe/Ti) and upwelling (captured by S/Ti and Ba/Ti) are nearly antiphase in the precession band, which suggests a contrast between summer and winter monsoon intensities. Strong obliquity signal in the Ba/Ti series is proposed to derive from changes in thermohaline circulation intensity from glaciation dynamics in southern Gondwana. The abundance of foraminifer, brachiopod and ostracod faunas within the Maokou Formation were mainly controlled by the ~1.1 Myr obliquity modulation cycle. The obliquity-forced high-nutrient and oxygen-depleted conditions generally produced a benthic foraminifer bloom, but threatened the brachiopod and ostracod faunas. [ABSTRACT FROM AUTHOR]

Termination of the late Paleozoic icehouse (LPI) serves as the Earth's first icehouse-to-greenhouse transition when the continents were covered by extensive vegetation. However, low-latitude climatic and biological responses to this climate transition remain unclear. In this study, we conducted a cyclostratigraphic analysis of a shallow marine succession of the Tieqiao section in South China. Variations in gamma rays that reflect continental weathering strength in the source regions are paced by Milankovitch cycles, including 405-kyr long eccentricity, 31.7-kyr obliquity, and ∼ 20-kyr (20.1 kyr and 18.7 kyr) precession. Based on the 405-kyr-scale cyclostratigraphic correlation between the Tieqiao section and the deep marine succession of Naqing, a floating astronomical time scale for the late Early Permian was constructed, and the base of the Kungurian stage was estimated as 284.83 ± 0.40 Ma. Climatic and astronomical variations were synchronized to this refined timescale and further compared with a geochronologically independent marine invertebrate biodiversity time series to interpret the dynamics of marine biological evolution during the late Paleozoic icehouse-to-greenhouse transition. The impacts of low-frequency obliquity forcing (with a period of ∼1.35 Myr) on climatic and biotic systems have differentiated in the changing climate backgrounds. When Gondwana land was minimally glaciated during the Artinskian, increased marine speciation was associated with elevated climatic humidity, nutrient inputs, linkage to glacial building at low-amplitude obliquity oscillation intervals (obliquity nodes). This cause-and-effect relationship gradually changed from ∼285.1 Ma, along with the termination of Gondwanan glaciation and tropical aridification over the long term. In an arid greenhouse, continental aridity and marine transgression at obliquity nodes led to a low nutrient level that the suppressed marine biodiversity. Our results show differential dynamics involving the Earth's astronomical parameters, climate change, and marine invertebrate biodiversity between icehouse and greenhouse conditions in the late Paleozoic Era. • The constructed astronomical time scale yields an age for the basal Kungurian stage of 284.83 ± 0.40 Ma. • Obliquity nodes led to climate humidity and marine speciation during the partially glaciated period. • Obliquity nodes led to aridity, marine transgression and reduced biodiversity in an ice-free world. [ABSTRACT FROM AUTHOR]

The late Ordovician Pingliang Formation on the southwestern margin of the Ordos Basin, North China, consists of rhythmic alternations of shale, limestone, and siliceous beds. To explore the possible astronomical forcing preserved in this lithological record, continuous lithological rank and magnetic susceptibility (MS) stratigraphic series were obtained from a ~ 34 m thick section of the Pingliang Formation at Guanzhuang. Power spectral analysis of the MS and rank series reveal 85.5 cm to 124 cm, 23 cm to 38 cm, and 15 cm to 27 cm thick sedimentary cycles that in ratio match that of late Ordovician short eccentricity, obliquity and precession astronomical cycles. The power spectrum of the MS time series, calibrated to interpreted short orbital eccentricity cycles, aligns with spectral peaks to astronomical parameters, including 95 kyr short orbital eccentricity, 35.3 kyr and 30.6 kyr obliquity, and 19.6 kyr and 16.3 kyr precession cycles. The 15 cm to 27 cm thick limestone–shale couplets mainly represent precession cycles, and siliceous bed deposition may be related to both precession and obliquity forcing. We propose that precession-forced sea-level fluctuations mainly controlled production of lime mud in a shallow marine environment, and transport to the basin. Precession and obliquity controlled biogenic silica productivity, and temperature-dependent preservation of silica may have been influenced by obliquity forcing. [ABSTRACT FROM AUTHOR]

The Ocean Drilling Program (ODP) Leg 184 recovered a continuous sedimentary sequence since Miocene at Site 1148 in the northern South China Sea (SCS), which provided a unique record for better understanding the tectonic, environmental and climatic evolution of the SCS. In this study, we report a detailed paleomagnetic study on 881 discrete samples from the upper 460 m cores of Hole 1148A through stepwise alternating field demagnetization (AF) or thermal demagnetization (TD). Rock magnetic results from isothermal remanent magnetization (IRM) acquisition, temperature dependence magnetic susceptibility (κ-T) and hysteresis loop parameters of representative samples indicate that the main magnetic mineral is low coercivity pseudo-single domain magnetite. The characteristic remanent magnetization (ChRM) with moderate downward or upward inclinations was identified after removing a low-stability drilling-induced remanence with steep downward inclinations. A new 23 Myr magnetostratigraphic time framework was established by correlating the magnetic polarity sequence to the Geomagnetic Polarity Time Scale 2012 (GPTS 2012; Ogg, 2012 ) in combination with biostratigraphic data. The mean sediment accumulation rates for lithostratigraphic Units V and IV, Unit III and lower Unit II, upper Unit II, Unit IB and Unit IA are calculated as ∼20.8 m/Myr, ∼15–17 m/Myr, 24.18 m/Myr, 17.07 m/Myr and 49.01 m/Myr, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The Early Cretaceous Jehol Biota in northeastern China provides an evolutionary window for ‘feathered’ dinosaurs, primitive birds, insects and early flowering plants. It also provides critical information for the biodiversity changes of the Early Cretaceous terrestrial ecosystem. Here we report a time series analysis for the 11.2-m-thick, fossil-bearing lacustrine deposits at the Sihetun section in western Liaoning, northeastern China on the basis of high-resolution magnetic susceptibility (MS) and anhysteretic remanent magnetization (ARM) measurements. A hierarchy of sedimentary cycle bands of 120–260cm, 50–67cm and 18–42cm was recorded in the MS and ARM series. With available radioisotope age constraints from the same section, sedimentary cycles of 120–260cm, 50–67cm and 18–42cm were interpreted as Milankovitch cycles of short eccentricity (130 and 95kyr), obliquity (36.6 and 46kyr), and precession (22.1, 20.9 and 18kyr), respectively. The 100kyr-tuned ‘floating’ astronomical time scale indicates that the duration of the 11.2-m-thick section is ~0.67Myr and the average depositional rate is ~1.70cm/kyr. The duration of the 1.8-m-thick, main fossil-bearing interval that contains 8 beds of ‘feathered’ dinosaur/primitive bird fossils can be estimated as short as 150kyr. The results suggest that climate fluctuations manifested in paleobotanical, sedimentological and geochemical records of the Yixian Formation may have been controlled by orbital forcing during Early Cretaceous. [Copyright &y& Elsevier]

Abstract: The Upper Cretaceous Qingshankou Formation (K2qn) in the Songliao Basin (SLB) of Northeast China consists of up to 550 m thick, lacustrine mudstone and shale that constitute one of the most important source rocks of the Daqing oil field. A high-resolution cyclostratigraphic analysis of the natural gamma-ray logging from 10 wells of the Qingshankou Formation (K2qn) reveals orbital cycles of precession (20 ka), obliquity (40 ka) and eccentricity (100 ka and 405 ka), providing strong evidence for astronomically driven climate changes in the Late Cretaceous terrestrial environments. Floating astronomical time scales (ATS) are established for all sections, which demonstrate variable durations of K2qn across the basin (1.09 Ma–5.20 Ma) and strong diachroneity of the lacustrine strata. Four periods of high depositional rates can be identified in the central parts of the basin, possibly recording deposition during times of sustained wet climate and high chemical weathering. An ATS established from well M206 in the central depression zone of the basin, where the most complete and stable Milankovitch cycles are present, suggests that the maximum duration of the K2qn is 5.20 Ma (from 94.27 Ma to 89.07 Ma; Late Cenomanian to Early Coniacian). The lacustrine anoxic event 1 (LAE1) at the Cenomanian–Turonian boundary lasted ~210–310 ka, during which the most prolific petroleum source rocks in SLB were deposited. The onset (~94.21–94.18 Ma) and duration (~210–310 Ka) of LAE1 in SLB are comparable to those of the oceanic anoxic event 2 (OAE2; onset at 94.21 Ma and duration of ~320–900 ka), suggesting that the same trigger mechanism, such as increased atmospheric CO2 from large-scale igneous activity, may have initiated high primary productivity and organic carbon burial in both marine and terrestrial systems. [Copyright &y& Elsevier]

As one of the most important greenhouse gases, CO 2 is considered a major controlling factor of Earth's climate over geological timescales. However, the origins of quasi-periodic fluctuations in p CO 2 on a million-year timescale remain unclear. Here, we used published datasets of atmospheric p CO 2 , oxygen isotopes of benthic foraminifera (δ18O benthic) and global mean sea-level (GMSL) from 23 Ma to the present to explore the pacing of p CO 2 changes and concomitant climatic effects using multiple time series analysis approaches. Our results indicate that the evolution of late Cenozoic p CO 2 and climate was paced by the grand orbital cycles, in particular the ∼4.5 Myr and ∼2.4 Myr eccentricity cycles, and ∼1.3 Myr obliquity cycle. Periodic occurrence of cold conditions was associated with low climate seasonality during the minima of ∼4.5 Myr and ∼2.4 Myr eccentricity cycles. We suggest that cooler conditions are associated with decreased atmospheric p CO 2 as a result of higher organic carbon burial due to lower metabolic rate of heterotrophic bacteria and more organic carbon export to the deep ocean. Furthermore, the buildup of glaciers during the minima of grand eccentricity cycles might lower p CO 2 via increased ice cover and enhanced dust fluxes. In contrast, high seasonal climate may lead to an opposite effect on atmospheric p CO 2 during the maxima of the grand eccentricity cycles. Moreover, we found a distinct shift in the dominant signal from eccentricity to obliquity cycles recorded in the p CO 2 , δ18O benthic and GMSL datasets at ∼13 Ma, a time when perennial sea ice occurred in the Arctic and significant ice growth shown in Antarctica. We suggest that the change in the type and distribution of the ice sheets would shift glacial response to orbital forcing and hence mediated global climate and p CO 2. Our analysis reveals a clear synchrony among atmospheric p CO 2 , climate change, and the grand orbital cycles in the late Cenozoic. • Late Cenozoic changes in p CO 2 and climate were paced by the grand orbital cycles • Astronomically forced seasonal changes modulated global sea surface temperature and ice volume • A switch in the dominant cycle from eccentricity to obliquity was detected at ∼13 Ma [ABSTRACT FROM AUTHOR]

The Hangenberg Event was one of the most significant mass extinctions accompanied by large-scale climate changes at the end of the Devonian period. Lack of precise and accurate geochronological constraints in the eastern Paleotethys has hindered a high-resolution global correlation of the Hangenberg Event. Here, we report the U–Pb dates of zircons from the bentonite samples intercalated with strata recording the Hangenberg Event in the Muhua region, Guizhou, South China, using both sensitive high-resolution ion microprobe (SHRIMP) and chemical abrasion - isotope dilution - thermal ionization mass spectrometry (CA-ID-TIMS) methods. A bentonite within the Hangenberg Event strata in the Muhua area was dated at 360.47 ± 0.68 Ma by CA-ID-TIMS, which is more precise than the results obtained by SHRIMP methods (361.5 ± 2.9 Ma and 359.8 ± 1.5 Ma). Thus, we propose that the Hangenberg Event took place at 360.47 ± 0.68 Ma in South China, based on the first precise CA-ID-TIMS zircon age from the Daposhang section. The age obtained from South China for the Devonian–Carboniferous boundary overlaps with that in Geologic Time Scale 2020, within the total uncertainties. • New U-Pb CA-ID-TIMS and SHRIMP zircon dates are reported from two bentonites around the Hangenberg Event in South China. • The Hangenberg Event occurred at 360.47 ± 0.68 Ma in the Daposhang section. • New age for Devonian–Carboniferous boundary overlaps with that in GTS 2020. [ABSTRACT FROM AUTHOR]

The Cryogenian nonglacial epoch (CNE) spans from the termination of the Sturtian snowball Earth (ca. 659 Ma) to the initiation of the Marinoan snowball Earth (ca. 649.2 Ma). The carbonate sequences formed in low latitudes record paleoclimatic and paleoceanographic changes during the CNE. Three negative carbon isotope (δ13C) excursions, named Rasthof, Tayshir and Trezona, are present at the bottom, middle, and top of the carbonate sequences, bracketing two intervals with highly positive δ13C values. Uranium isotope (δ238U) data from Mongolia reveal ocean redox changes linked to δ13C variations during the CNE, marked by the development of anoxic deep ocean to extensive oxygenation and subsequent deoxygenation. However, the timing and duration of these paleoceanographic events and δ13C excursions have not been adequately investigated. Here, we report new environmental magnetic results of the higher paleo-latitudinal, siliciclastic-dominated Datangpo Formation (Fm) in South China that may help constrain the age and correlation of the CNE geochemical events. We identified four segments of the Datangpo Fm based on the magnetic susceptibility (MS) profile and other environmental magnetic parameters, which are, in ascending order, the ascent segment (Da), lower stable-segment (Db), transition segment (Dc), and upper stable-segment (Dd). These segments are dated by the astronomical time scale as 659–655.6 Ma (Da), 655.6–653.3 Ma (Db), 653.3–652.3 Ma (Dc), and 652.3–649.2 Ma (Dd). Environmental magnetism analyses show that the highest magnetite concentration but lowest fine-grained magnetite contents are present in "Da", followed by "Dd" and "Db". These results suggest a sea-level fall and a potential decrease in oxygenation after the deposition of the transition segment (Dc), implying that a cooling climate started ∼4 Myr before the Nantuo glaciation (Marinoan snowball Earth). Ocean redox variations revealed by environmental magnetism in the Datangpo Fm are consistent with those reported from the low-latitudinal carbonate sequences. "Da" likely corresponds to the Rasthof δ13C excursion and "Dc" corresponds to the Tayshir δ 13C excursion; whereas "Db" and "Dd" probably correspond to the two intervals with positive δ 13C values. • Four segments of the Cryogenian nonglaciatial epoch in South China are identified and the time of each segment is constrained. • Environmental magnetism analyses show a climate cooling ∼4 Myr before the Nantuo glaciation (or Marinoan snowball Earth). • Siliciclastic depositions in South China are linked to carbonate depositions in low-latitude continents. [ABSTRACT FROM AUTHOR]

Recent studies of the upper Gaoyuzhuang Formation (Fm) (ca. 1600–1540 Ma) in north China have suggested that Earth underwent an oxygenation event associated with a negative δ13C carb excursion and this event may have led to the expansion of eukaryotic life. However, the duration of this negative δ13C carb excursion, which is crucial to understand its origin, remains uncertain. Here, we report a floating astronomical timescale based on Milankovitch cycles extracted from the carbonate-dominated strata of the Member 3 of the Gaoyuzhuang Fm in north China, in which the oxygenation event is recorded. High-resolution magnetic susceptibility, anhysteretic remnant magnetization and saturation isothermal remnant magnetization series were obtained from the stratigraphic sections in the Jixian and Yanqing regions. Rock magnetic experiments suggest that the magnetic parameters are dominated by the detrital materials whose flux was likely controlled by orbitally forced climatic changes. Our results for the first time reveal well-constrained eccentricity, obliquity, and precession cycles from the Gaoyuzhuang Fm and demonstrate that the ca. 1560 Ma negative δ13C carb excursion and associated transient oxygenation event indicated by I/(Ca + Mg) had durations of ~1.7 Myr and ~6.2 Myr, respectively. The ca. 1560 Ma δ13C carb excursion is comparable with the short-term Neoproterozoic excursions in respect of duration, rather than with the long-term ones such as the ca. 574–567 Ma Shuram excursion. The similarity may indicate a common mechanism in origin of the short-term excursions in the Mesoproterozoic and Neoproterozoic time, which deserve testing by more investigations. • Cyclostratigraphic analyses revealed Milankovitch cycles from the ca. 1.56 Ga Gaoyuzhuang Formation • Durations of the δ13C carb excursion and the oxygenation event in the ca. 1.56 Ga are 1.7 Myr and 6.2 Myr, respectively • The duration of this δ13C carb excursion are comparable to the short-term ones in the Neoproterozoic [ABSTRACT FROM AUTHOR]

The evolution of the Neo-Tethys Ocean had a profound effect on global climate change and the evolution of life. To better constrain the Cretaceous paleogeographic position of the Tethyan Himalaya and evolution of the Neo-Tethys Ocean, combined paleomagnetic and detrital zircon U Pb geochronological research was performed on samples from the Gyabula Formation, constrained at ca. 117.7–94.4 Ma, in the Zhongba area of the northern Tethyan Himalaya. Both positive fold and reversal tests combined with a maximum grouping at 106% unfolding indicate that the high-temperature component directions were acquired before folding and were most likely of primary origin. The tilt-corrected directions yielded a paleopole at 29.2°N, 280.5°E with A 95 = 5.1° and a corresponding paleolatitude of −29.0° ± 5.1°N for the sampled area (29.7°N, 84.0°E). No significant inclination shallowing was identified from the sampled cherts. Comparison of the observed paleolatitude with those expected from the Indian craton indicated that an 840 ± 670 km north-south distance existed between the northern Tethyan Himalaya and the Indian craton for the reference point (29.7°N, 84.0°E). Because of the anticlockwise rotation of the Indian craton, this amounts to a crustal extent of 1130 ± 900 km at ca. 106 Ma, which represents the amount of north-south crustal shortening. Our new results, together with reliable Cretaceous paleomagnetic data obtained from the Tethyan Himalaya, indicate that no wide oceanic basin extended between the Tethyan Himalaya and Indian craton at ca. 106–75 Ma and that there was still a contiguous Indian subcontinent. • The Zhongba area of the northern Tethyan Himalaya (TH) was located at 29.0° ± 5.1°S at ca. 117.7–94.4 Ma • 1130 ± 900 km of north-south shortening occurred between the northern Tethyan Himalaya and the Indian craton • No wide oceanic basin extended between the TH and the Indian craton at ca. 106–75 Ma [ABSTRACT FROM AUTHOR]

Abstract: Cretaceous climate data of the long-lived Cretaceous Songliao Basin (SB) in eastern Asia is correlated and compared with the Western Interior Seaway (WIS) on the northern American plate, in order to understand better the dynamics of the Earth's past ‘greenhouse’ climates. Nearly continuous Late Cretaceous terrestrial deposition in the Songliao Basin is represented by two cores totaling 2431m in length. The Turonian–Maastrichtian age of the section is based on integrated stratigraphy, and is comparable in age with Upper Cretaceous strata in the WIS. Being consistent with global trends, the dynamic Late Cretaceous climates of both the SB and WIS gradually cooled from the warmest Albian–Cenomanian time to the end of the Maastrichtian with several intervening warm periods as did the global climate. However regional differences existed, the Songliao Basin climate was humid to semi-humid, warm temperate–subtropical and the Western Interior Seaway was in the humid, warm temperate zone and experienced only moderate climatic changes. The shifts of oxygen isotope data in the Songliao Basin were frequent and abrupt, whereas WIS records more gradual change affected mainly by fresh-water runoff mixing with southern Tethyan and northern Arctic waters. Sedimentary cycles of eccentricity, obliquity and precession bands are recorded in both the SB and WIS basins. The sedimentary cycles in the WIS and SB are interpreted to be related to variations of the wet/dry runoff cycles, which indicate that orbital forcing played an important role in global climate change in Late Cretaceous. The most favorable condition for organic carbon burial in both the SB and WIS basin was bottom water anoxia regardless of the cause of the anoxia. But the organic carbon burial rate was usually much higher in the Songliao Lake than in the WI epeiric sea suggesting that giant lakes may serve as important sinks of atmospheric CO2. In both basins organic-rich deposits formed during a rise in water level and incursion of saline waters. The integration of paleoclimate data from Cretaceous marine deposits and terrestrial sedimentary record will promote our understanding of the Cretaceous ‘greenhouse’ climate change and may provide insights for a future greenhouse world. [Copyright &y& Elsevier]

From the latest Cretaceous (late Campanian to Maastrichtian, ~75–66 Ma) to the earliest Paleogene, fluctuations in greenhouse climate, inferred primarily from marine sediments, have been linked to volcanism, the Chicxulub asteroid impact, and the Cretaceous-Paleogene (K-Pg) mass extinction. In this paper, we summarize terrestrial climate records in mid-latitude East Asia during the latest Cretaceous and across the K-Pg boundary, based on a multi-proxy approach from the geochronologically well-constrained Sifangtai and Mingshui formations (SMF), accessed by scientific drilling of the Songliao Basin in northeastern China. Evolution of sedimentary environments is characterized by five depositional units of fluvial-deltaic-lacustrine facies. Development of four types of paleosols, including Inceptisols, Aridisols, Vertisols and Alfisols, is interpreted to primarily reflect climatic changes. Correlations among sedimentary facies, paleosol features, illite chemistry index, chemical index of alteration, as well as stable and clumped isotopes of pedogenic carbonates and clay minerals of the SMF validate their reliability for paleoclimate reconstruction, and indicate significant fluctuations in terrestrial climate and sedimentary environment. During global warming intervals possibly triggered by volcanism (e.g. ~69.5–68.5 Ma), the Songliao Basin experienced a warmer and wetter climate with stronger terrestrial chemical weathering and more monsoon-derived moisture sourced from the Pacific. In contrast, during global cooling intervals (e.g. ~70.5–69.5 Ma and ~ 68.5–66.5 Ma), the SMF record a cooler and drier climate with less intensive chemical weathering and more westerlies-derived moisture. Across the K-Pg boundary, dramatic changes in land temperatures and hydroclimate correspond to the latest Maastrichtian warming episode (~66.4–66.1 Ma), the transient cooling preceding the K-Pg boundary (~66.1–66.0 Ma), and the earliest Paleogene warming interval (~66.0–65.7 Ma). Temporal correlation of weathering index changes with the Deccan Traps volcanism suggests that volcanism and subsequent intensified weathering played a major role for climatic changes across the K-Pg boundary. The integrated records of sedimentological and geochemical datasets from the Songliao Basin robustly demonstrate that the terrestrial climate of mid-latitude East Asia responded strongly to greenhouse climate changes and to the catastrophic geological events from the latest Cretaceous to the earliest Paleogene. [ABSTRACT FROM AUTHOR]