{"title":"Solos e superfícies de erosão: uma contextualização da evolução da paisagem na Serra do Espinhaço Meridional (SdEM), Minas Gerais","authors":"C. Varajão, A. F. D. C. Varajão, F. S. Oliveira","doi":"10.5281/ZENODO.3937475","DOIUrl":null,"url":null,"abstract":"The study investigated the landscape evolution of Serra do Espinhaco Meridional (SdEM), MG, through the macromorphological, mineralogical, micromorphological and chemical characterization of soils developed from the main regional lithostratigraphic units. There are mainly Neossols and Cambisols, decapitated by erosion and covered discordantly by a paleo-pavement. Considering climatic variations, erosion surfaces and recent soil dating, we understand that after long desert conditions in the Cretaceous (Post-Gondwana Surface) until the Paleocene (South American Surface), there was an abrupt climatic variation in the Eocene, in which hot and humid conditions formed the weathered mantles and the dismantling of the quartz veins from the underlying geological units (Supergroup Espinhaco). These conditions were also present during the Miocene, disappearing in the Pliocene, where the installation of a new desert climate promoted the disappearance of vegetation and the consequent erosion-decapitating of soil profiles. In this context, the aforementioned regional paleo-pavement was formed and interpreted as contemporary to the Surface Velhas. Over it, during the Quaternary, countless peatlands were formed, suggesting mild regional climatic conditions.","PeriodicalId":231740,"journal":{"name":"Revista Espinhaço","volume":"123 4 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2020-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"5","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Revista Espinhaço","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.5281/ZENODO.3937475","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 5
Abstract
The study investigated the landscape evolution of Serra do Espinhaco Meridional (SdEM), MG, through the macromorphological, mineralogical, micromorphological and chemical characterization of soils developed from the main regional lithostratigraphic units. There are mainly Neossols and Cambisols, decapitated by erosion and covered discordantly by a paleo-pavement. Considering climatic variations, erosion surfaces and recent soil dating, we understand that after long desert conditions in the Cretaceous (Post-Gondwana Surface) until the Paleocene (South American Surface), there was an abrupt climatic variation in the Eocene, in which hot and humid conditions formed the weathered mantles and the dismantling of the quartz veins from the underlying geological units (Supergroup Espinhaco). These conditions were also present during the Miocene, disappearing in the Pliocene, where the installation of a new desert climate promoted the disappearance of vegetation and the consequent erosion-decapitating of soil profiles. In this context, the aforementioned regional paleo-pavement was formed and interpreted as contemporary to the Surface Velhas. Over it, during the Quaternary, countless peatlands were formed, suggesting mild regional climatic conditions.
通过对主要区域岩石地层单元发育的土壤的宏观形态、矿物学、微观形态和化学特征,研究了MG埃斯皮纳哈科山脉经向(Serra do Espinhaco Meridional, SdEM)的景观演变。主要有新溶质和cambisol,由于侵蚀而被切断,并被古路面不协调地覆盖。考虑到气候变化、侵蚀面和最近的土壤年代测定,我们了解到,在白垩纪(后冈瓦纳表面)到古新世(南美表面)的漫长沙漠条件之后,始新世发生了一次突然的气候变化,其中炎热潮湿的条件形成了风化的地幔,并从下面的地质单元(超群埃斯皮纳科)中解体了石英脉。这些条件在中新世期间也存在,但在上新世消失了,在上新世,新的沙漠气候的出现促进了植被的消失和随之而来的侵蚀——土壤剖面的破坏。在这种背景下,上述区域的古路面形成并被解释为与地表Velhas同时代。在第四纪,无数泥炭地在其上形成,表明温和的区域气候条件。