The NE–NNE-trending Yuan-Ma Basin in central South China, an overprinted basin, is important for understanding the transition in Mesozoic intracontinental deformation in South China from compressional to extensional settings. A detailed sedimentary and structural cross-section across the basin reveals the Upper Triassic – Lower Jurassic black coal-bearing shale, greyish-green sandstone and brick-red claystone, and the Middle Jurassic brick-red sandstone, pebbly sandstone and conglomerate in the eastern segment of the basin. The Lower Cretaceous brick-red coarse sandstone, pebbly sandstone and siltstone occurred in the western and central segments, as well as fault breccia and Lower Cretaceous sandstone at the western margin of the basin. Detrital zircon U–Pb dating by laser ablation inductively coupled plasma mass spectrometry shows that the magmatic and metamorphic zircons yield significant age clusters at 900–700, 500–350 and 300–150 Ma, as well a minor age cluster at 120–100 Ma. Synthesizing the stratigraphic sequences, structures, isotopic dating results and palaeocurrent data, we infer that the Yuan-Ma Basin experienced three evolutionary stages and tectonic settings: (1) during Late Triassic – Early Jurassic time, the Yuan-Ma Basin was related to the diachronous progressive intracontinental deformation as a result of the early Mesozoic Xuefeng intracontinental orogeny in South China; (2) during Middle–Late Jurassic time, the Yuan-Ma Basin was related to intracontinental compression in South China; and (3) during late Early Cretaceous time, the Yuan-Ma Basin was constrained by the intracontinental extension that occurred in eastern China. These three stages, a result of various tectonic regimes, caused the intracontinental deformation that was controlled by the evolution of the continents and their margins.
Aiming at the strategies to improve the brand value of fresh products, this paper uses the field research data, official data, public information data in the industry, etc. in the cold fresh meat market as the data basis of the research, and uses cluster analysis to divide the cold fresh meat consumer groups into potential group and main force group, conservative group and follow-suit group. And it uses SPSS and mathematical modeling to analyze the characteristic portraits of the four categories of people, and gives strategies to improve the brand value of fresh products through correlation analysis.
A perfect tea production base can promote the development mechanism of regional tourism brand and improve the evaluation value of regional brand. A complete driving mechanism of regional tourism brand development of tea production base can promote the local economic development and the improvement of national economy. And with a certain scientific mathematical model to evaluate the role of this mechanism is the necessary content of the development of this mechanism. As a result, this article adopts the Difference-inDifference to analysis tea production base of regional brand, and study on the use of Difference-in-Difference of the various influence factors on the role of the output value. It gives a series of comparison of the predictive value and the actual value, and found the problems about tea base and related regional brand, and put forward the corresponding opinions and suggestions.
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