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The Lopingian is one of the fastest rising periods of seawater strontium isotopic ratios (Sr/Sr) in earth history, and its mechanisms and increasing rates of the Sr/Sr evolution were still disputed widely. These disputations among researchers were caused mainly by timeframe selection (sections' thickness or data of radiometric ages), and different stratigraphic boundaries and un-upmost dated ages. This paper examined published Sr/Sr data of the Lopingian, and projected them on timescales based on evolutionary and age constrained conodonts fossils. Sr/Sr evolution vs fossil constraining timescales was re-established in this period. This research suggests: (1) Sr/Sr excursion projects on fossil zones can truly support Sr/Sr evolutionary pattern in the period; (2) Sr/Sr evolution provides a new approach for stratigraphic research of marine carbonate sections in lieu of biostratigraphic data; (3) Sr/Sr stratigraphy works on marine carbonate sections of different sedimentation rates even between different basins; (4) the Sr/Sr data and its shift was dependent on samples materials and chemical treatment methods; (5) the increasing rate of marine water Sr/Sr in the Late Permian is suggested as 5.4×10/Ma or slightly lower; (6) sedimentation age and its Sr/Sr of the Lopingian marine carbonate suggested as: D=259-( R−0.70695)/5.4×10±1 Ma. [ABSTRACT FROM AUTHOR]

The late Paleozoic ice age was the longest icehouse of the Phanerozoic with complex terrestrial ecosystems and metazoan life. Simulations of late Paleozoic climate have confirmed the coupled relationship between Gondwanan ice dynamics and paleotropical climate on a multitude of timescales. However, it is still unclear how precipitation in the tropical zone would respond to changes in paleoclimate during the late Paleozoic ice age. Here, we present detailed sedimentological and biostratigraphic works on a late Carboniferous mixed carbonate-siliciclastic succession from the southeastern South China Block to explore sedimentary responses to paleoclimate variations. Conodont and fusulinid biostratigraphy indicate that the Outangdi succession formed during the middle to late Moscovian. Detailed facies analysis suggests that the succession was deposited on a carbonate ramp, episodically punctuated by braid delta sedimentation. Given the relatively stable tectonic setting and well-correlated, coeval siliciclastic deposition in the paleotropical peri-Paleotethys regions, the abrupt increase in siliciclastic influx in the late Moscovian resulted from an enhanced precipitation event associated with the glacial-to-interglacial shift. • An abrupt siliciclastic influx were recorded in tropical peri-Paleotethys regions in the late Moscovian • Water cycle would be enhanced in the paleotropical zone responding to the demise of glacial interval • Anomalous siliciclastic deposits could have been driven by climate factors. [ABSTRACT FROM AUTHOR]