P-T-t paths and differential Alleghanian loading and uplift of the Bronson Hill terrane, South Central New England

Clicks: 4
ID: 298743
2003
Free PDF
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal
Steady

Ranked #191 of 8,486 articles by views in american journal of science

Most read Least read

Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 8,486 in total.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Sign in to mint
Abstract
Late Paleozoic U-Pb ages of sphene and ^40^Ar/^39^Ar cooling ages of amphibole and muscovite from rocks of the Bronson Hill terrane in Connecticut and central Massachusetts reflect a late Paleozoic (Alleghanian) overprint on Acadian metamorphic rocks. Prograde Alleghanian sphenes crystallized during the Late Pennsylvanian, and eliminate the possibility that amphibole ages reflect delayed Permian cooling from Devonian Acadian metamorphism. Fourteen new amphibole ages from Connecticut form a north-to-south trend of decreasing age from 294 to 245 Ma, while in Massachusetts four new amphibole ages together with three others from the literature produce a random Carboniferous pattern. Seven new muscovite ages support existing data indicating uniform cooling throughout the Bronson Hill terrane through ∼350°C in the Early Triassic. The rate of Permian cooling defined by amphibole-muscovite pairs increases from ∼4°C/my in northern Connecticut to ∼50°C/my near Long Island Sound. Hinged loading and hinged but delayed exhumation in the southern part of the Bronson Hill terrane (with the hinge in central Connecticut) explain these ages and cooling rates as well as a southerly increasing metamorphic field gradient. One-dimensional thermal modeling indicates that loading of Bronson Hill rocks must have begun by the Late Mississippian. The time of peak Alleghanian metamorphic temperature decreases southward from Early Permian in northern Connecticut to Late Permian to the south. These results demonstrate that the metamorphic effects of the Alleghanian orogeny are not restricted to the Avalon terrane of southeastern New England. On the contrary, the Alleghanian orogeny reset ^40^Ar/^39^Ar mineral ages, recrystallized minerals, partially melted felsic rocks, and transposed fabrics at least as far west as the Bronson Hill terrane in south-central New England.
Reference Key
openalex_W1992652479 Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors Robert P. Wintsch
Journal american journal of science
Year 2003
DOI
10.2475/ajs.303.5.410
URL
https://ajs.scholasticahq.com/article/61696.pdf
Keywords Keywords not found

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

Comments

No comments yet. Be the first to comment on this article.