Science & Engineering Faculty
Read

The contrasting geologic record of inferred “hot” intraoceanic and “cold” continental margin subduction initiation

Publication Date Jun 21, 2022

Abstract

ABSTRACT Two contrasting field relationships may reflect different tectonic settings of subduction initiation preserved in orogenic belts. “Hot” subduction initiation assemblages include a large ophiolite unit (up to kms thick, extending tens to hundreds of km along strike) with supra subduction zone (SSZ) geochemical affinity that structurally overlies a thin (<500 m thick) sheet of high-pressure (HP), high-temperature (HT), primarily metamafic rocks called a metamorphic sole. The ophiolite generally lacks burial metamorphism and includes variably serpentinized peridotite at its base. The sole structurally overlies subduction complex rocks made up of oceanic materials (igneous part of oceanic crust and overlying pelagic sedimentary rocks, and clastic sedimentary rocks of trench fill affinity) and/or passive margin assemblages; some of the subduction complex may be metamorphosed under HP-low temperature (LT) conditions (such as blueschist facies). The field relationships suggest initiation of subduction within young (<15 My) and “hot” oceanic lithosphere and that the sole represents the first slice(s) of material transferred from the subducting to upper plate. Examples include the Neotethyan and northern Appalachian ophiolites and units beneath them, and the Coast Range ophiolite and subjacent Franciscan subduction complex of California. “Cold” subduction initiation assemblages lack SSZ ophiolite and island arc components and a metamorphic sole. Instead, the upper plate above the s...

Concepts

Subduction Complex Subduction Initiation Coast Range Ophiolite Alpine Orogenic Belt Supra Subduction Zone Continental Margin Blueschist Facies Geochemical Affinity Oceanic Lithosphere Oceanic Crust

Round-ups are the summaries of handpicked papers around trending topics published every week. These would enable you to scan through a collection of papers and decide if the paper is relevant to you before actually investing time into reading it.

Climate change Research Articles published between Nov 14, 2022 to Nov 20, 2022

R DiscoveryNov 21, 2022
R DiscoveryArticles Included:  2

The world needs to move quickly towards sustainability that should characterize all production and consumption patterns. We use cookies to improve you...

Read More

Coronavirus Pandemic

You can also read COVID related content on R COVID-19

R ProductsCOVID-19

ONE PROBLEM . ONE PURPOSE . ONE PLACE

Creating the world’s largest AI-driven & human-curated collection of research, news, expert recommendations and educational resources on COVID-19

COVID-19 Dashboard

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on “as is” basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The Copyright Law.