Pre-Silurian Stratigraphic Succession in Central Western Maine

Boudette, Eugene L.; Boone, Gary M.

doi:10.1130/mem148-p79

Cited by 19 publications

(11 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The zircon age of 1,600 m.y. is tentatively considered the age of metamorphism, and indirect evidence suggests an original Archean age (Boudette and Boone, 1982). The unusual fragmental textures of the diamictite facies, the age of the rocks, and complex strain lamellae in quartz all suggest an impact origin (Boudette and Boone, 1982).…”

Section: Suspect Terranes Outboard Of the North American Miogeoclinementioning

confidence: 96%

See 1 more Smart Citation

Appalachian suspect terranes

Williams

Hatcher²

1983

Geological Society of America Memoirs

281

135

View full text Add to dashboard Cite

Since the advent of plate tectonics, the widely accepted model for the development of the Appalachian orogen has involved the opening and closing of a late Precambrian-Paleozoic Iapetus Ocean. Only a few of a growing number of geologically distinctive terranes are easily explained by this model. Vestiges of Iapetus are nowhere coupled to the ancient North American margin. Furthermore, it cannot be demonstrated that any of the extensive Appalachian terranes, now east of the Iapetus tract or its suture, were once connected to the North American miogeocline. All are therefore suspect.The major suspect terranes of the Appalachian orogen are in most respects analogous to previously recognized zones or tectonic lithofacies belts. In the north, these are the Dunnage, Gander, Avalon, and Meguma terranes. In the south, they include easterly parts of the Blue Ridge, the Piedmont, Slate Beit, and the geophysically distinctive Brunswick and Tallahassee-Suwannee terranes beneath the Atlantic Coastal Plain. Most of these are composite and include smaller terranes of uncertain paleogeography. Taconic allochthons are included because they fit the definition of suspect terranes.Stratigraphic and sedimentologic analyses indicate that the Appalachian orogen built up during three major Paleozoic accretionary events. Their timing coincides with the times of structural, metamorphic, and plutonic effects assigned to the Taconian, Acadian, and Alleghanian orogenies.Accretion of the Appalachian orogen progressed from the North American miogeocline outward. The boundaries of the earliest accreted western terranes are marked by melange zones and ophiolite complexes, implying head-on collisions. Later boundaries between eastern terranes are steep mylonite zones and brittle faults, implying oblique movements.The suspect terrane concept, first developed for the North American Cordilleran, provides new insights into the evolution of the Appalachian orogen and solves several enigmas. It is a surgically clean analytical approach and a superior framework in which to view the anatomy of any complex orogen. 33 on May 15, 2015 memoirs.gsapubs.org Downloaded from

show abstract

Section: Suspect Terranes Outboard Of the North American Miogeoclinementioning

confidence: 96%

“…The Chain Lakes terrane is bordered by a steeply dipping Upper Cambrian or Ordovician ophiolite complex to the south; it is intruded by Paleozoic granite to the east, and it is faulted against or unconformably overlain by Silurian sedimentary rocks to the north Boone, 1976, 1982).…”

Section: Suspect Terranes Outboard Of the North American Miogeoclinementioning

confidence: 99%

Appalachian suspect terranes

Williams

Hatcher²

1983

Geological Society of America Memoirs

281

135

View full text Add to dashboard Cite

show abstract

“…Ophiolites are exposed in two main belts, one along the Baie Verte-Brompton line (Williams & St-Julien 1982) from western New England through the Thetford area, Quebec, to Gaspé, and to Newfoundland, and a second belt, containing ophiolite of the Boil Mountain Complex in the Boundary Mountains anticlinorium in northwestern Maine (Boudette & Boone 1976;Boudette 1982;Kusky et al 1997). The Boil Mountain Complex is emplaced above the Chain Lakes "massif" , a unit now interpreted as a detrital assemblage of older high-grade Proterozoic gneiss fragments, probably deposited in the late Proterozoic proximal to the Laurentian margin (Dunning & Cousineau 1990;Trzcienski et al 1992a) and intruded by the Ordovician 463 Ma Attean pluton (Fig.…”

Section: Ophiolite Emplacement and Its Settingmentioning

confidence: 99%

Paleozoic orogens in New England, USA

Robinson

Tucker²,

Bradley

et al. 1998

GFF

156

131

View full text Add to dashboard Cite

“…As described by Boudette (1978Boudette ( , 1982, the Boil Mountain Complex is composed (in ascending order) of serpentinized harzburgite-lherzolite, pyroxenite, and epidiorite-gabbro. He tentatively included a layer of tonalite at the top of the sequence, although he allowed (1982, p. 220) that it is slightly discordant and might not properly belong to the ophiolite.…”

Section: Stratigraphy Of the Bronson Hill Beltmentioning

confidence: 99%

Stratigraphy, geochronology, and accretionary terrane settings of two Bronson Hill arc sequences, northern New England

Moench¹,

Aleinikoff²

2003

Physics and Chemistry of the Earth, Parts A/B/C

View full text Add to dashboard Cite

The Ammonoosuc sequence is defined by the Middle Ordovician Ammonoosuc Volcanics near Littleton, NH, the type area, northeast to Milan, NH, and Oquossoc, ME; it also includes black slate of the Partridge Formation (C. bicornis--zone graptolites, $457 Ma). Related metamorphosed intrusives are the tonalitic Joslin Turn pluton (469 AE 2 Ma), the Cambridge Black granitic pluton (468 AE 3 Ma), and gabbro, tonalite (467 AE 4 Ma), and sheeted diabase of the Chickwolnepy intrusions. These intrusives cut lowermost Ammonoosuc (therefore >469 Ma). Probable uppermost Ammonoosuc is dated at 465 AE 6 and 461 AE 8 Ma. Successively below the Ammonoosuc are the Dead River and Hurricane Mountain Formations (flysch and melange), and the Jim Pond Formation (484 AE 5 Ma) and Boil Mountain Complex (both ophiolite), which are structurally underlain by the Neoproterozoic(?) Chain Lakes massif.The Quimby sequence is defined by the Lower Silurian(?) to Upper Ordovician Quimby Formation, composed of bimodal volcanics (443 AE 4 Ma) and sulfidic shale and graywacke that lie conformably to unconformably above the Ammmonoosuc Volcanics and Partridge Formation. Also in the Quimby sequence are several granitic to sparsely gabbroic plutons of the Highlandcroft (441-452 Ma) and Oliverian (435-456 Ma) Plutonic Suites, which intrude the Dead River, Ammonoouc and Partridge, but not the Quimby Formation.Based on faunal, paleolatitude, and isotopic data, the Ammonoosuc sequence and its correlatives and underlying sequences formed off the southern Laurentian margin, but northwest of the principal Iapetan suture, or Red Indian line. The Boil MountainJim Pond-Hurricane Mountain sequence was ramped northwestward over the Chain Lakes massif at $475 Ma, on the basal Boil Mountain surface. This obduction probably occurred slightly before obduction on the Baie Vert-Brompton surface (BBL), farther NW, over the Laurentian margin, and was followed by Dead River flysch sedimentation, which ended with the abrupt onset of Ammonoosuc-sequence arc magmatism at $470 Ma. Ammonoosuc eruptions probably ended at $460 Ma, when Iapetus closed along the Red Indian line.During a following magmatic hiatus of $3-5 m.y., now represented by portions of the Partridge Formation that overlie the Ammonoosuc Volcanics, subduction polarity reversed, and subduction resumed below the northwest-dipping Brunswick subduction complex (BSC) of New Brunswick, Canada. Quimby-sequence magmatism ($456-435 Ma) on the newly accreted Laurentian margin occurred above the BSC, whose footwall is now buried to the southeast by mainly Silurian clastic sediments of the MerrimackFredericton trough, deposited in the ''Fredericton Sea''. In Silurian to Early Devonian time, the NW-dipping BSC footwall was paired with a SE-dipping subduction zone that produced arc magmas of the Coastal Volcanic belt, built on the composite Avalon and adjacent peri-Avalonian terranes. Orogen-normal extension produced by rapid rollback of both subduction zones narrowed the Fredericton Sea, produced the Central Maine and Connecti...

show abstract

Pre-Silurian Stratigraphic Succession in Central Western Maine

Cited by 19 publications

References 0 publications

Appalachian suspect terranes

Appalachian suspect terranes

Paleozoic orogens in New England, USA

Stratigraphy, geochronology, and accretionary terrane settings of two Bronson Hill arc sequences, northern New England

Contact Info

Product

Resources

About