Crustal structure of the southeastern Grenville Province, northern New York State and eastern Ontario

1992 ◽  
Vol 97 (B12) ◽  
pp. 17455 ◽  
Author(s):  
Stephen Hughes ◽  
James H. Luetgert
Keyword(s):  
New York ◽  
Crustal Structure ◽  
New York State ◽  
Grenville Province ◽  
York State ◽  
Eastern Ontario

scholarly journals Late Ottawan orogenic collapse of the Adirondacks in the Grenville province of New York State (USA): Integrated petrologic, geochronologic, and structural analysis of the Diana Complex in the southern Carthage-Colton mylonite zone

Geosphere ◽  
2020 ◽  
Vol 16 (3) ◽  
pp. 844-874
Author(s):  
Graham B. Baird
Keyword(s):  
New York ◽  
Pure Shear ◽  
New York State ◽  
Shear Zones ◽  
Core Complex ◽  
Grenville Province ◽  
York State ◽  
Mylonite Zone ◽  
Ductile Shear Zones ◽  
Metamorphic Core

Abstract Crustal-scale shear zones can be highly important but complicated orogenic structures, therefore they must be studied in detail along their entire length. The Carthage-Colton mylonite zone (CCMZ) is one such shear zone in the northwestern Adirondacks of northern New York State (USA), part of the Mesoproterozoic Grenville province. The southern CCMZ is contained within the Diana Complex, and geochemistry and U-Pb zircon geochronology demonstrate that the Diana Complex is expansive and collectively crystallized at 1164.3 ± 6.2 Ma. Major ductile structures within the CCMZ and Diana Complex include a northwest-dipping penetrative regional mylonitic foliation with north-trending lineation that bisects a conjugate set of mesoscale ductile shear zones. These ductile structures formed from the same 1060–1050 Ma pure shear transitioning to a top-to-the-SSE shearing event at ∼700 °C. Other important structures include a ductile fault and breccia zones. The ductile fault formed immediately following the major ductile structures, while the breccia zones may have formed at ca. 945 Ma in greenschist facies conditions. Two models can explain the studied structures and other regional observations. Model 1 postulates that the CCMZ is an Ottawan orogeny (1090–1035 Ma) thrust, which was later reactivated locally as a tectonic collapse structure. Model 2, the preferred model, postulates that the CCMZ initially formed as a subhorizontal mid-crustal mylonite zone during collapse of the Ottawan orogen. With continued collapse, a metamorphic core complex formed and the CCMZ was rotated into is current orientation and overprinted with other structures.

BIOLOGICAL NOTES ON SOME OF OUR EASTERN ONTARIO HAPLOPTILIA SPECIES (LEPID.) WITH DESCRIPTIONS OF TWO NEW SPECIES

1933 ◽  
Vol 65 (7) ◽  
pp. 160-168 ◽  
Author(s):  
J. McDunnough
Keyword(s):  
New York ◽  
New Species ◽  
New York State ◽  
Field Work ◽  
York State ◽  
Two New Species ◽  
Field Notes ◽  
Eastern Ontario

During field work at Bobcaygeon, Ont., in the summers of 1931 and 1932 I paid particular attention to the collecting and breeding of Haploptilia larvae and was successful in securing considerably over a dozen species. As very little has been published on this interesting group apart from Heinrich's excellent treatment in Forbes' Lepidoptera of New York State (1924, Mem. 68, Cornell Univ. Agr. Exp. Sta. pp. 202-217) it has occurred to me that the publication of my field notes, combined with a photographic figure of the characteristic larval case pertaining to each species, might be of value to students.

A Principal Reference Section Proposed for the Nepean Formation of Probable Tremadodan Age Near Ottawa, Ontario

1972 ◽  
Vol 9 (8) ◽  
pp. 933-941 ◽  
Author(s):  
Robert G. Greggs ◽  
Ivor J. Bond
Keyword(s):  
New York ◽  
New York State ◽  
Shallow Sea ◽  
York State ◽  
Desiccation Cracks ◽  
Dominant Feature ◽  
Eastern Ontario ◽  
Reference Section

A principal reference section for the Nepean Formation in Eastern Ontario is proposed. This section is located west of Ottawa, Ontario in Nepean Township and south of the original Nepean quarries which supplied much of the stone used in the construction of the Parliament Buildings. These quarries are now filled in and little outcrop is visible.The Nepean sandstones are considered to be an offshore deposit of a shallow sea. The sandstone beds low in the section show foreset bedding, oscillation ripple marked surfaces, desiccation cracks, and occasional burrowing. Bioturbation is a dominant feature in the upper beds of the sequence.Throughout southeastern Ontario, the Nepean Formation unconformabîy overlies the Precambriam, and is overlain with a sharp, possibly disconformable contact, by the March Formation of Tremadocian age. The Nepean Formation is considered to be younger than the Potsdam Formation of Potsdam County, New York State, and to be Lower Tremadocian.

scholarly journals A Review of Boron-Bearing Minerals (Excluding Tourmaline) in the Adirondack Region of New York State

Minerals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 644 ◽  
Author(s):  
David G. Bailey ◽  
Marian V. Lupulescu ◽  
Robert S. Darling ◽  
Jared W. Singer ◽  
Steven C. Chamberlain
Keyword(s):  
New York ◽  
New York State ◽  
Grenville Province ◽  
York State ◽  
Metasedimentary Rocks ◽  
Upstate New York ◽  
Geological Processes ◽  
Boron Minerals ◽  
Metamorphic Terranes ◽  
Raman Spectral Data

Boron is a biologically important element, but its distribution in the natural environment and its behavior during many geological processes is not fully understood. In most metamorphic and igneous environments, boron is incorporated into minerals of the tourmaline supergroup. In high-grade metamorphic terranes like that of the Adirondack region of northern New York State, uncommon rock compositions combined with unusual and variable geologic conditions resulted in the formation of many additional boron-bearing minerals. This paper reviews the occurrences and geological settings of twelve relatively uncommon boron-bearing minerals in the southern Grenville Province of upstate New York and provides new chemical and Raman spectral data for seven of these minerals. The boron minerals range from relatively simple metal borates (e.g., vonsenite), to chemically complex borosilicates (e.g., prismatine), to a relatively rare borosilicate-carbonate (e.g., harkerite). Some are of primary igneous origin, while others are formed by a variety of prograde and retrograde metamorphic processes or by metasomatic/hydrothermal processes. Most of the boron minerals are formed within, or adjacent to, metasedimentary lithologies that surround the anorthositic massifs of the central Adirondacks. The metasedimentary rocks are thought to be the source of most of the boron, although additional boron isotope studies are needed to confirm this and to constrain the mechanisms of the formation of these unusual minerals.

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