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The article focuses on findings of a study on Zircon U-Pb Age of the Babu Ophiolites in Southeast Yunnan, China and Constrains of Plate Subduction Time. It states that mafic and ultramafic rocks have been inferred to be part of the Emeishan large igneous province (LIP) by some researchers, and mentions that Zircon grains from sample TGZl as euhedral or prismatic. It notes that mafic and ultramafic rocks in Malipo do not belong to part of the Emeishan LIP.

Hydroclimate is an important factor controlling landscape evolution. But establishing the impact of hydroclimate is complicated by the influences of other processes and is especially hard to prove for those in deep time from geological record. During the late Permian, voluminous basaltic sediments were derived from the erosion of the Emeishan large igneous province in western South China. They provide a unique record critical in understanding the responses of tropical basaltic erosion to hydroclimate change without impacts of orogenic uplift, lithologic variation, vegetational difference and glacial‐interglacial change. Sampled successions define a negative carbon isotope excursion capable of making regional and global stratigraphic correlations in the middle Wuchiapingian interval corresponding to the final phase of the late Paleozoic ice age. This interval is associated with a petrofacies shift and a decreasing source weathering intensity, a downward shift of erosion loci, and a reduced coastal water paleosalinity. Applying present‐day temperature dependence pattern of basaltic weathering and using land surface temperatures approximated from nearby paleo‐seawaters, denudation rates were calculated for the Emeishan basaltic province and shows an increase from ∼71 to ∼107 m/Ma. This erosional acceleration is temporally correlated with a decrease in paleosalinity and likely linked to enhanced freshwater discharge in the middle Wuchiapingian. Scaling and landscape erosion modeling suggest ∼80%–130% increase in catchment precipitation could have driven this acceleration in denudation. Our work provides a positive test for the hydroclimate forcing on landscape erosion in deep time and underlines the mechanistic linkage of sediments with erosion and climate change. Plain Language Summary: Sedimentary records provide a unique way to track source weathering and erosion in the deep geological past. During the late Permian to early Triassic voluminous basaltic sediments were eroded from the Emeishan large igneous province, which was emplaced at ca. 260 Ma in southwestern China, into the adjacent basins. These late Permian sedimentary records are studied to understand the denudation of this tropical basalt province in the final period of the late Paleozoic ice age (LPIA). Our data reveal a negative organic carbon isotope excursion, decreasing weathering intensity and deepening erosional loci in the Emeishan basaltic province, and a reduced salinity due to greater rainfall in the middle Wuchiapingian interval. Denudation rate was estimated for the Emeishan province and a correlation of high denudation rates with lowered paleosalinity was documented in the Wuchiapingian. The accelerated denudation in the Emeishan basaltic province was ascribed to ∼80%–130% increase in catchment precipitation during the final phase of the late Paleozoic ice age. This work highlights the importance of sedimentary records to understand the deep time landscape evolution. Key Points: A negative carbon isotope excursion enables middle Wuchiapingian stratigraphic correlations from South China to GondwanaA decrease in weathering intensity and a deepening of erosional exhumation are indicated for the Emeishan basaltic provinceDenudation was accelerated due to ∼80%–130% increase in precipitation during the late Permian in SW China [ABSTRACT FROM AUTHOR]

The Pennsylvanian to lower Permian succession at Madiyi, South China, represents a nearshore mixed siliciclastic‐carbonate system characterized by cyclic sedimentation patterns along a depth gradient from continental siliciclastics to marine open platform carbonates. Various palaeokarst features related to subaerial exposure are widely distributed. Additionally, pedogenesis was pervasive. The identification of twenty‐eight sedimentary cycles grouped into five sequences allows the reconstruction of a relative sea‐level curve. The cycles represent higher frequency changes superimposed on the long‐term evolution. After the initial transgression, the sea level remained relatively low in the late Bashkirian to early Moscovian. Then, it rose stepwise until a major drop occurred in the late Moscovian. Afterwards, the sea level rose again, but marine sedimentation ceased during at least the early Kasimovian. The area was flooded in the late Kasimovian, and the sea level rose until a late Gzhelian sea‐level drop. The subsequent marine sequence contains uppermost Gzhelian to upper Asselian deposits, which are capped by lower Permian continental facies associated with a major regional regression. Shallow to deeper marine sedimentary settings recorded high‐frequency sea‐level changes throughout South China during the late Bashkirian to Asselian. The main transgression–regression cycles are clearly associated with different depositional settings during several time intervals. Furthermore, the good correlations among South China, Ukraine, and the U.S. Mid‐continent are rooted in the impact of Gondwanan glaciations on the global sedimentation patterns. However, not all changes at Madiyi are the result of glacio‐eustatic sea‐level fluctuations; some are related to the local subsidence history and the rise of the Xuefeng Uplift. [ABSTRACT FROM AUTHOR]

The article presents research conducted on Late Devonian tuff in Qinzhou region in south of Guangxi Zhuang Autonomous Region and also conducted zircon U-Pb dating on it to constrain extension of the Paleo-Tethys Ocean in the South China Block. The research concludes that Devonian tuff in research area could be related to Late Devonian oceanic basin opening.