The significance of various garnet types in surficial materials in southeastern Gaspé Peninsula, Quebec

1995 ◽  
Vol 32 (6) ◽  
pp. 730-740 ◽  
Author(s):  
Yvon T. Maurice

The distribution patterns of four types of garnet in surficial materials of southeastern Gaspé Peninsula are interpreted in terms of the glacial history of the area, the lithostratigraphy of the bedrock, and mineral occurrences. Each type is derived from a distinct source, and all have undergone at least some southeastward glacial dispersion. Type 1 garnets, anhedral Ca-garnet fragments, are from the McGerrigle granite metamorphic aureole and were brought into the region by the same ice flow that caused the well-documented southward dispersal of granite debris. Their distribution within the study area depicts the southern part of this important dispersal train with an improved degree of precision. Type 2 garnets, Ca-garnet crystals, seem to be related to skarns within the boundaries of the study area; some patterns cannot be linked to any known source, thus providing challenging exploration opportunities. Type 3 garnets, colored pyralspite garnet crystals, are related to a tectonic breccia within the Maquereau–Mictaw contact zone. Type 4 garnets, Grenville-type anhedral garnets, were not brought into the region by Laurentide ice, as one might suspect, but rather seem to be related to specific horizons within the Silurian Lower Chaleurs Group. On the basis of a palinspastic reconstruction of southern Gaspé Peninsula and a plate tectonic model for the Paleozoic of eastern North America, we propose that these garnets were derived from the erosion of a metamorphic Grenvillian terrane, which presently forms the Northwestern Highlands Zone of Cape Breton Island. The distribution data for this garnet type also lends support to the concept put forth in a previous study whereby a local Late Wisconsinan ice mass penetrated some 5–6 km into the region from the southeast near Saint-Godefroi.

Psilophyton princeps , though still incompletely known, is one of the most important Early Devonian plants, both on account of its morphology and of the place it occupies in the history of investigation of Pre-carboniferous vegetation. It was originally distinguished and described by Dawson from specimens collected in the Gaspé peninsula, Canada. As shown in the restoration, published in the ‘Geological History of Plants’ (DAWSON, 1882), he regarded the plant as consisting of horizontally growing rhizomes, from which sprang erect branch-systems; the branching was dichotomous and the fine distal ramifications terminated in large ovoid sporangia. From the description (DAWSON, 1871) it is clear that the lower portions of the sub-aerial branch-systems were markedly spiny, while the spines, though present, became less numerous and more distant in the distal, fertile regions. The distribution of the spines according to Dawson is not shown in his restoration; it is well illustrated in a modification of Dawson’s restoration by PIA (1926, fig. 109).


2002 ◽  
Vol 39 (10) ◽  
pp. 1541-1551 ◽  
Author(s):  
Pierre Jutras ◽  
Gilbert Prichonnet

The Saint-Jules Formation, a post-Acadian continental clastic unit previously mapped as part of the Bonaventure Formation (pre-Namurian unit), was recently identified in the southern Gaspé Peninsula of Quebec. The Saint-Jules Formation in the study area is confined to a small post-sedimentary graben. The unit is characterized by fault-controlled, oxidized, and poorly sorted detritus that underwent short transportation by fluvial processes. The Saint-Jules Formation is locally overlain by a massive groundwater calcrete several metres in thickness, which is tentatively correlated with the calcretization event that has affected the base of the La Coulée Formation grey clastics (pre-Namurian unit). The calcrete has developed within the karstified upper beds of the Saint-Jules Formation, which brings new insights into the potential hosts of such calcretes and on the potential stratigraphic confusion that such diagenetic overprints can create. Partial erosion of both the La Coulée and Saint-Jules clastic rocks, as well as the massive groundwater calcretes, occurred prior to deposition of the Bonaventure Formation. Like the La Coulée and Bonaventure formations, the Saint-Jules is undated, but unconformably overlies Acadian structures (Middle Devonian) and predates Mabou Group units (Namurian).


1985 ◽  
Vol 22 (12) ◽  
pp. 1871-1877 ◽  
Author(s):  
Pierre Bail

The last glacial event in the Saint Godefroi area (Gaspé Peninsula) was a glacier from the southeast that was flowing towards the northwest before it stopped at the margin of the Saint Jogues Plateau. This interpretation is based on the following features: distribution of erratic boulders, till fabrics, a frontal moraine, and an outwash plain turned towards north. According to the study of the area located to the south of the Baie des Chaleurs, the glacier probably flowed at the beginning of the late Wisconsinan and disappeared before 14 000 years BP. [Journal Translation]


2012 ◽  
Vol 31 (2) ◽  
pp. 268-274 ◽  
Author(s):  
Michael T. Hirschmann ◽  
Stephan Schön ◽  
Faik K. Afifi ◽  
Felix Amsler ◽  
Helmut Rasch ◽  
...  

1961 ◽  
Vol 93 (2) ◽  
pp. 118-123 ◽  
Author(s):  
J. G. Pilon ◽  
J. R. Blais

Nearly all forest regions in the Province of Quebec where balsam fir (Abies balsamea (L.) Mill.) is an important tree component have been subjected to severe defoliation by the spruce budworm, Choristoneura fumiferana (Clem.), during the past 20 years. These outbreaks have followed an easterly direction beginning near the Ontario-Quebec border in 1939 and ending in the Gaspé Peninsula in 1958.


1980 ◽  
Vol 17 (1) ◽  
pp. 19-35 ◽  
Author(s):  
James T. Teller ◽  
Mark M. Fenton

The history of Late Wisconsinan glaciation in southwestern Manitoba has been established by identifying and correlating ice-laid lithostratigraphic units in the subsurface. Five Late Wisconsinan tills are defined on the basis of their texture, mineralogic composition, and stratigraphic position. These new formations are, from youngest to oldest, Marchand, Whitemouth Lake, Roseau, Senkiw, and Whiteshell Formations.Late Wisconsinan ice first invaded southeastern Manitoba 22 000 to 24 000 years ago. This Laurentide glacier advanced from the northeast across the Precambrian Shield and deposited the sandy Whiteshell and Senkiw tills, which contain abundant Precambrian rock fragments and minerals and few Paleozoic carbonate grains. Shortly after this, Keewatin ice advanced from the northwest over Paleozoic carbonate rocks, depositing the loamy carbonate-rich Roseau Formation throughout most of the area. This ice remained over southeastern Manitoba until after 13 500 years ago, when it rapidly retreated northward with Lake Agassiz on its heels. Two brief glacial readvances occurred. The first overrode Lake Agassiz lacustrine sediment as far south as central North Dakota shortly after about 13 000 years ago. The clayey Whitemouth Lake till was deposited in southern Manitoba at this time. After a rapid retreat, the ice briefly pushed southward over southeastern Manitoba about 12 000 years ago to just south of the International Boundary. The sandy carbonate-rich Marchand Formation was deposited at this time as the ice overrode its own sandy outwash. By 11 000 years ago, ice had disappeared from southeastern Manitoba.


Boreas ◽  
2008 ◽  
Vol 29 (4) ◽  
pp. 295-314 ◽  
Author(s):  
JOHN SHAW ◽  
DOUGLAS R. GRANT ◽  
JEAN-PIERRE GUILBAULT ◽  
THANE W. ANDERSON ◽  
D. RUSSELL PARROTT

Author(s):  
Andriani Andriani ◽  
Ikhsan Romli

In an industry, the maintenance department plays a very important role in ensuring the smooth production process. The method of machine maintenance with preventive maintenance is a strategy that can be used to repair existing machines. This is related to proper and regular maintenance can improve engine performance and reduce the level of engine damage which will increase the continuity of production activities. In the die casting division of PT Astra Honda Motor in the observation on the die casting machine 07 there were 45 times damage to the ladle component and 11 times the damage to the auto spray component. These two components are critical components of the 07 die casting machine. After testing the compatibility index and the good compatibility of the damage time data and repair time data to obtain distribution data distribution patterns, obtain the tablespoon component MTTF assessment results of 107,833 hours and auto spray components amounting to 314,226 hours. Whereas the MTTR value of the spoon component is 0.385 hours and the auto spray component is 0.766 hours. The next step is to look for critical component replacement time intervals with the age replacement model, to further review whether it is related to increased reliability, decrease in total downtime, and cost savings before preventive maintenance is carried out and after preventive maintenance is carried out.


2021 ◽  
Vol 48 (2) ◽  
pp. 156-168
Author(s):  
Melika Tabasi ◽  
Ahmadreza Mehrabian ◽  
Sadaf Sayadi

Abstract Assessing distribution patterns of valuable taxa plays an important role in the biodiversity conservation of these taxa. The genus Crocus L. (Iridaceae) comprises about 100 species that are distributed mainly in the Mediterranean region and western Asia. The present study purposed to assess the distribution patterns of Iranian Crocus species (including C. sativus L. and 8 wild species) and their conservation status in Iran as one of diversity centers of Crocus in the Middle East. A set of geographic distribution data was compiled through field studies, and reviews of herbarium specimens, iNaturalist, and various Flora. Localities were marked on geo-referenced maps (1/106) of Iran using ArcView version 3.2 (Esri, 2000). The distribution patterns of the taxa were mapped per 0.25° × 0.25° universal transverse Mercator grid cells (25 km2 with the exception of boundary area). Based on the species distribution (SDI) (33%) and species specialization (SSI) (44%) indices, those Iranian Crocus species that are threatened are mainly distributed in Irano-Turanian region. The mountainous ecosystems of Almeh and Western Alborz are important distribution centers of these taxa. Iranian Crocus species with SSI < 0.5 (C. almehensis, C. gilanicus, C. michelsonii, and C. caspius) have the highest conservation value.


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