U-Th-Pb geochronology of the Massabesic Gneiss and the granite near Milford, South-Central New Hampshire: New evidence for avalonian basement and taconic and alleghenian disturbances in Eastern New England
Contributions to Mineralogy and Petrology
Links
- More information: Publisher Index Page (via DOI)
- Download citation as: RIS | Dublin Core
Abstract
U-Th-Pb systematics for zircon and monazite from Massabesic Gneiss (paragneiss and orthogneiss) and the granite near Milford, New Hampshire, were determined. Zircon morphology suggests that the paragneiss may be volcaniclastic (igneous) in origin, and thus the age data probably record the date (minimum of 646 m.y.) at which the rock was extruded. A two-stage lead-loss model is proposed to explain the present array of data points on a concordia diagram. Orthogneiss ages range only narrowly and are clustered around 475 m.y. Data for the granite of Milford, New Hampshire, are scattered, but may be interpreted in terms of inheritance and modern lead loss, yielding a crystallization age of 275 m.y. This is the only known occurrence of Avalonian-type basement in New Hampshire and as such provides evidence for the location of the paleo-Africa-paleo- North America suture. The geochronology also further documents the occurrence of disturbances during the Ordovician and Permian. ?? 1979 Springer-Verlag.
| Publication type | Article |
|---|---|
| Publication Subtype | Journal Article |
| Title | U-Th-Pb geochronology of the Massabesic Gneiss and the granite near Milford, South-Central New Hampshire: New evidence for avalonian basement and taconic and alleghenian disturbances in Eastern New England |
| Series title | Contributions to Mineralogy and Petrology |
| DOI | 10.1007/BF00371877 |
| Volume | 71 |
| Issue | 1 |
| Year Published | 1979 |
| Language | English |
| Publisher location | Springer-Verlag |
| Larger Work Type | Article |
| Larger Work Subtype | Journal Article |
| Larger Work Title | Contributions to Mineralogy and Petrology |
| First page | 1 |
| Last page | 11 |
| Google Analytic Metrics | Metrics page |