Cauldron Subsidence and Fluidization: Mechanisms of Intrusion of the Coastal Batholith of Peru into Its Own Volcanic Ejecta

Abstract

Research Article| September 01, 1975 Cauldron Subsidence and Fluidization: Mechanisms of Intrusion of the Coastal Batholith of Peru into Its Own Volcanic Ejecta JOHN S. MYERS JOHN S. MYERS 1Geological Survey of Greenland, Østervoldgade 10, Copenhagen, Denmark Search for other works by this author on: GSW Google Scholar Author and Article Information JOHN S. MYERS 1Geological Survey of Greenland, Østervoldgade 10, Copenhagen, Denmark Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1975) 86 (9): 1209–1220. https://doi.org/10.1130/0016-7606(1975)86<1209:CSAFMO>2.0.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation JOHN S. MYERS; Cauldron Subsidence and Fluidization: Mechanisms of Intrusion of the Coastal Batholith of Peru into Its Own Volcanic Ejecta. GSA Bulletin 1975;; 86 (9): 1209–1220. doi: https://doi.org/10.1130/0016-7606(1975)86<1209:CSAFMO>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The Coastal Batholith of Peru shows how diorite, tonalite, granodiorite, and granite magmas rose through their last few kilometers by a process of magmatic stoping by their fluidized upper surface. The magmas successively displaced both older, more basic plutons and their own volcanic debris downward and came to rest within 3 km of the Earth's surface after loosing volatiles by eruptions through fissures and calderas. There was a continuous association between volcanic eruptions and plutonic intrusions from at least 100 to 30 m.y. ago in a narrow belt parallel with the continental margin.The batholith is 50 km wide, more than 1,100 km long, and probably 15 km or less thick. It has steep walls and an extensively preserved flat roof exposed in mountainous desert with relief of 4,500 m. It consists of plutons and sheets which were intruded in five distinct episodes into the same tabular belt by repeated cauldron subsidence. Each subsidence was preceded by the formation of small shear zones which were fractured and fluidized, and accompanied by the rise of corrosive, turbulent gas-liquid-solid mixtures. Individual plutons form relatively thin tabular bodies with flat roofs and floors and steep walls which pass downward into ring dikes and upward into ring dikes and calderas. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.