scholarly journals Impact-induced hydrothermal activity within the Haughton impact structure, arctic Canada: Generation of a transient, warm, wet oasis

2001 ◽  
Vol 36 (5) ◽  
pp. 731-745 ◽  
Author(s):  
Gordon R. OSINSKI ◽  
John G. SPRAY ◽  
Pascal LEE
2013 ◽  
Vol 48 (2) ◽  
pp. 211-223 ◽  
Author(s):  
Keith DEWING ◽  
Brian R. PRATT ◽  
Thomas HADLARI ◽  
Tom BRENT ◽  
Jean BÉDARD ◽  
...  

2019 ◽  
Vol 56 (9) ◽  
pp. 983-993
Author(s):  
Jérôme Gattacceca ◽  
William Zylberman ◽  
Adam B. Coulter ◽  
François Demory ◽  
Yoann Quesnel ◽  
...  

The East and West Cleawater Lake impact structures (Wiyâshâkimî Lake, Québec), ∼26 and 32 km in diameter, respectively, have been proposed to represent an impact doublet. We investigated their paleomagnetism to contribute to this debate. The paleomagnetic directions of the impact melt rocks and impact melt-bearing breccias from the West Clearwater structure are compatible with the radiometric age of 280–290 Ma previously determined for this structure and indicate that the impact occurred during a reverse polarity interval of the geomagnetic field. A similar remagnetization direction is found in the basement within 10 km of the structure center, whereas basement farther away from the center has escaped remagnetization by the impact. Samples for the East Clearwater structure come from two holes drilled in 1963 and 1964. Unfortunately, the drill hole through the melt rocks is tilted by 30° from the vertical with an unknown azimuth. The paleomagnetic inclination of these melt rocks cannot be constrained to better than between −28° and +32°. This is, however, distinct from the inclination of the melt rocks of the West Clearwater Lake impact structure (−27.8° ± 3.7°), suggesting that the two structures do not represent an impact doublet, in agreement with recent radiometric dating. The basement rocks and the melt rocks within 10 km of the center of the West Clearwater Lake impact structure show a magnetic signature of titanohematite that crystallized during postimpact hydrothermal activity under oxidizing conditions. This is not observed in the basement or the melt rocks from the East Clearwater Lake impact structure.


2013 ◽  
Vol 48 (12) ◽  
pp. 2491-2516 ◽  
Author(s):  
Gernot Arp ◽  
Claudia Kolepka ◽  
Klaus Simon ◽  
Volker Karius ◽  
Nicole Nolte ◽  
...  

Author(s):  
Byung-Hun Choe ◽  
Gordon R. Osinski ◽  
Catherine D. Neish ◽  
Michael Zanetti ◽  
Livio L. Tornabene ◽  
...  

2021 ◽  
Vol 11 ◽  
pp. 3-15
Author(s):  
N. S. Kovalchuk ◽  
◽  
B. A. Makeev ◽  
S. A. Svetov ◽  
◽  
...  

We studied Upper Paleozoic (P1pt-ng) carbonaceous shales and siltstones from the area of the Ust'-Kara astrobleme (PayKhoy). We analyzed mineralogical and geochemical features of carbonaceous rocks of the target in the vicinity of the Ust'-Kara astrobleme event using a complex of modern methods to identify possible mobilization, redeposition and concentration of ore substance under intensive post-impact hydrothermal activity. Geochemical features of carbon deposits, altered by post-impact hydrothermal processes in the vicinity of the Ust'-Kara impact structure, have been determined. We found anomalous contents of Ti, Mn, Cr, Zr, Ni, Li, Co, Sc and REE. Inherent rare metal and rare earth minerals (monazite, florensite), sulfides (pyrite, chalcopyrite, marcasite, sphalerite), apatite, barite, anatase, chrome spinels were diagnosed.


2005 ◽  
Vol 40 (12) ◽  
pp. 1859-1877 ◽  
Author(s):  
Gordon R. Osinski ◽  
Pascal Lee ◽  
John Parnell ◽  
John G. Spray ◽  
Martin Baron

Author(s):  
Maria Herrmann ◽  
Carl Alwmark ◽  
Michael Storey

ABSTRACT Crater-forming events are generally followed by the development of hydrothermal systems due to the rapid heating of the target rock. Such hydrothermal systems are a feature of nearly all large terrestrial impact structures. For the Siljan impact structure in Sweden, there is evidence for such a fossil hydrothermal system, possibly triggered by the impact event ca. 380 Ma. To investigate the thermal regime of the near-surface hydrothermal activity of the Siljan crater, biotite and amphibole grains extracted from samples collected in a transect across the high-pressure regime recorded by the central uplift, as well as from distal localities outside the central uplift of the crater, were dated using the 40Ar/39Ar laser step-heating technique. Our results show that biotite from inside the central uplift, which was strongly altered to chlorite by low-temperature (200–340 °C) hydrothermal reactions, yields strongly disturbed age spectra. The first and second (low laser power) step ages range from ca. 1300 to 190 Ma. In contrast, biotite from outside the central uplift and amphibole, irrespective of location inside or outside of the central uplift, are much less altered, which is reflected in less disturbed, near-flat age spectra. This result indicates that the hydrothermal temperatures inside the central uplift were >200 °C, sufficient to disturb the K-Ar system of biotite during its chloritization, but too low to affect the amphibole (closure temperature of 480–580 °C). In contrast, the temperature of the hydrothermal system outside of the central uplift was <200 °C, as no significant reset of the K-Ar system can be observed in either biotite or amphibole. Our results are consistent with estimated trapping temperatures from fluid inclusion studies, which show a decrease from 327–342 °C within the central uplift to 40–225 °C toward outside the central uplift. We conclude that the near-surface hydrothermal system in the Siljan impact structure was an impact-triggered system. This system was strongly active, with its highest temperature inside the central uplift and decreasing rapidly toward the outlying part of the crater.


1998 ◽  
Vol 10 (3) ◽  
pp. 589-606 ◽  
Author(s):  
Erik F.F. Sturkell ◽  
Curt Broman ◽  
Per Forsberg ◽  
Peter Torssander

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