Spatially and Temporally Associated Porphyry Deposits with Distinct Cu/Au/Mo Ratios, Woodjam District, Central British Columbia

2017 ◽  
Vol 112 (7) ◽  
pp. 1673-1717 ◽  
Author(s):  
Irene del Real ◽  
Farhad Bouzari ◽  
Amelia Rainbow ◽  
Thomas Bissig ◽  
Jacqueline Blackwell ◽  
...  
Keyword(s):  
British Columbia ◽  
Hydrothermal System ◽  
Small Volume ◽  
Time Interval ◽  
Structural Level ◽  
Magmatic Evolution ◽  
Porphyry Deposits ◽  
Porphyry Cu ◽  
High K ◽  
The Difference

Abstract The Woodjam district is a cluster of porphyry Cu-Au deposits of Early Jurassic age (~196 Ma) and is located in the Quesnel terrane in central British Columbia. Porphyry centers include the Southeast zone Cu-Mo porphyry, the Deerhorn and Megabuck Au-Cu porphyries, and the Takom and Three Firs Cu-Au porphyries. The Takomkane batholith, which intruded strata of the Nicola Group and is host to the Southeast zone, has characteristics of a calc-alkalic Cu-Mo porphyry. The Deerhorn, Megabuck, and Takom deposits are centered on narrow monzonite bodies with pencil-like geometries that intruded the Nicola Group volcanic sequence. These small volume intrusions have characteristics of high K calc-alkalic intrusions. The Southeast zone, Deerhorn, Megabuck, and Takom deposits have similar ages and their intrusive units can be divided into two groups with distinct geochemical characteristics. Differences between alteration and mineralization of the deposits are attributed to the magmatic evolution of the system as well as differences in the depth of emplacement and preservation. Based on stratigraphic relationships, the Deerhorn and Megabuck deposits are interpreted to be emplaced at the shallowest structural level in the district and have the highest Au/Cu ratios and the lowest temperature alteration assemblages. The Southeast zone is hosted by the felsic units in the Takomkane batholith and represents the deepest parts of the hydrothermal system. Cu-Au mineralization in the Takom deposit shows characteristics intermediate between the Southeast zone and the Deerhorn deposit. Based on stratigraphic interpretations the difference in depth of emplacement between the Southeast zone and Megabuck is about 1,400 m, with Takom being emplaced about 400 m above the Southeast zone. The Woodjam district illustrates the variety of styles of porphyry mineralization that can form over a restricted time interval (<1 m.y.) within a single district.

Petrogenesis and Magmatic Evolution of the Guichon Creek Batholith: Highland Valley Porphyry Cu ± (Mo) District, South-Central British Columbia☼

2017 ◽  
Vol 112 (8) ◽  
pp. 1857-1888 ◽  
Author(s):  
Michael D’Angelo ◽  
Alfaro Miguel ◽  
Pete Hollings ◽  
Kevin Byrne ◽  
Stephen Piercey ◽  
...  
Keyword(s):  
British Columbia ◽  
Magmatic Evolution ◽  
Porphyry Cu ◽  
South Central

Chemical Variations in Hydrothermal White Mica Across the Highland Valley Porphyry Cu-Mo District, British Columbia, Canada

2020 ◽  
Vol 115 (4) ◽  
pp. 903-926 ◽  
Author(s):  
Tatiana Alva-Jimenez ◽  
Richard M. Tosdal ◽  
John H. Dilles ◽  
Gregory Dipple ◽  
Adam J.R. Kent ◽  
...  
Keyword(s):  
British Columbia ◽  
High Temperature ◽  
White Mica ◽  
Porphyry Deposits ◽  
Porphyry Cu ◽  
Form Part ◽  
Similar Vein ◽  
Alkali Elements ◽  
Pale Green ◽  
Porphyry Cu Deposit

Abstract Hydrothermal white mica in the Highland Valley district, British Columbia, is present in high-temperature alteration assemblages in early halo veins and in intermediate-temperature sericitic alteration assemblages in D-type veins. Pale-gray white micas characterize early halo veins in the Valley and Bethsaida zone porphyry Cu-Mo deposits, whereas pale-green white micas form texturally similar vein halos along the margin of the Valley deposit and at the Alwin vein. White micas in the Bethlehem porphyry Cu-Mo deposit form part of a sericitic alteration assemblage associated with D-type veins that overprinted K-silicate–altered rocks. Cation compositions in white micas indicate phengitic compositions trending toward aluminoceladonite. Pale-gray phengitic white micas intergrown with bornite-chalcopyrite-molybdenite contain elevated Na, indicating higher formation temperatures than those that characterize phengitic white micas formed during hydrolytic alteration. Bethlehem phengitic white micas have cation compositions similar to those of pale-green phengitic white micas at the Valley deposit margin, Bethsaida zone margin, and the Alwin vein. The Al-OH absorption wavelengths in pale-gray phengitic white micas are shorter than in pale-green phengitic white mica or phengitic white mica in the sericitic assemblage. In the phengitic white micas, alkali elements substituting in the interlayered site are positively correlated, whereas higher-valence elements substituting into the octahedral site show a greater variability. The data confirms that hydrothermal white-mica chemistry varies between paragenetic stages of a porphyry Cu deposit and between multiple porphyry deposits in a district.

Laramide to Miocene syn-extensional plutonism in the Puerta del Sol area, central Sonora, Mexico

2017 ◽  
Vol 34 (1) ◽  
pp. 45 ◽  
Author(s):  
Elizard González-Becuar ◽  
Efrén Pérez-Segura ◽  
Ricardo Vega-Granillo ◽  
Luigi Solari ◽  
Carlos Manuel González-León ◽  
...  
Keyword(s):  
Metamorphic Core Complex ◽  
Primitive Mantle ◽  
Isotopic Ratios ◽  
Magmatic Evolution ◽  
Calc Alkaline ◽  
Core Complex ◽  
High K ◽  
Sierra Madre ◽  
Plutonic Rocks ◽  
Metamorphic Core

Plutonic rocks of the Puerta del Sol area, in central Sonora, represent the extension to the south of the El Jaralito batholith, and are part of the footwall of the Sierra Mazatán metamorphic core complex, whose low-angle detachment fault bounds the outcrops of plutonic rocks to the west. Plutons in the area record the magmatic evolution of the Laramide arc and the Oligo-Miocene syn-extensional plutonism in Sonora. The basement of the area is composed by the ca. 1.68 Ga El Palofierral orthogneiss that is part of the Caborca block. The Laramide plutons include the El Gato diorite (71.29 ± 0.45 Ma, U-Pb), the El Pajarito granite (67.9 ± 0.43 Ma, U-Pb), and the Puerta del Sol granodiorite (49.1 ± 0.46 Ma, U-Pb). The younger El Oquimonis granite (41.78 ± 0.32 Ma, U-Pb) is considered part of the scarce magmatism that in Sonora records a transition to the Sierra Madre Occidental magmatic event. The syn-extensional plutons are the El Garambullo gabbro (19.83 ± 0.18 Ma, U-Pb) and the Las Mayitas granodiorite (19.2 ± 1.2 Ma, K-Ar). A migmatitic event that affected the El Palofierral orthogneiss, El Gato diorite, and El Pajarito granite between ca. 68 and 59 Ma might be related to the emplacement of the El Pajarito granite. The plutons are metaluminous to slightly peraluminous, with the exception of El Oquimonis granite, which is a peraluminous two-mica, garnet-bearing granite. They are mostly high-K calc-alkaline with nearly uniform chondrite-normalized REE and primitive-mantle normalized multielemental patterns that are characteristic of continental margin arcs and resemble patterns reported for other Laramide granites of Sonora. The Laramide and syn-extensional plutons also have Sr, Nd and Pb isotopic ratios that plot within the fields reported for Laramide granites emplaced in the Caborca terrane in northwestern and central Sonora. Nevertheless, and despite their geochemical affinity to continental magmatic arcs, the El Garambullo gabbro and Las Mayitas granodiorite are syn-extensional plutons that were emplaced at ca. 20 Ma during development of the Sierra Mazatán metamorphic core complex. The 40Ar/39Ar and K-Ar ages obtained for the El Palofierral orthogneiss, the Puerta del Sol granodiorite, the El Oquimonis granite, and the El Garambullo gabbro range from 26.3 ± 0.6 to 17.4 ± 1.0 Ma and are considered cooling ages associated with the exhumation of the metamorphic core complex.

scholarly journals Annual Spread Rate of Tomentosus Root Disease

Plant Disease ◽  
1997 ◽  
Vol 81 (9) ◽  
pp. 1053-1056 ◽  
Author(s):  
R. S. Hunt ◽  
F. G. Peet
Keyword(s):  
British Columbia ◽  
Tree Ring ◽  
Root Disease ◽  
Uninfected Control ◽  
Radial Increment ◽  
Spread Rate ◽  
Annual Increment ◽  
Temporal Differences ◽  
The Difference ◽  
A New Technique

The spread rate of tomentosus root disease, caused by Inonotus tomentosus, was investigated by a new technique employing temporal differences in the initiation of the reduced annual radial increment between pairs of diseased trees. Pairs of infected trees (stumps) located on the periphery of disease centers were selected in each of six widely separated spruce (Picea spp.) stands in British Columbia. Distances between 12 pairs of stumps were measured, and disks were collected from each stump. Similarly, disks from four additional pairs were collected from trees in a younger stand. Uninfected control disks were collected for all sites. Tree-ring measurements were determined for all disk samples and the year in which the reduction of the annual increment attributable to I. tomentosus began was determined for infected trees. The difference between initiation years for pairs of infected trees divided into the distance between them produced an average annual spread rate of 20 cm/yr. This rate will be used in developing a model for the disease.

scholarly journals A scoping review of chronotype and temporal patterns of eating of adults: Tools used, findings, and future directions

2021 ◽  
pp. 1-51
Author(s):  
Yan Yin Phoi ◽  
Michelle Rogers ◽  
Maxine P. Bonham ◽  
Jillian Dorrian ◽  
Alison M. Coates
Keyword(s):  
Energy Intake ◽  
Scoping Review ◽  
Assessment Tool ◽  
Temporal Patterns ◽  
Time Interval ◽  
Dark Cycle ◽  
Future Directions ◽  
Meal Skipping ◽  
Optimal Health ◽  
The Difference

Abstract Circadian rhythms, metabolic processes, and dietary intake are inextricably linked. Timing of food intake is a modifiable temporal cue for the circadian system and may be influenced by numerous factors, including individual chronotype—an indicator of an individual’s circadian rhythm in relation to the light-dark cycle. This scoping review examines temporal patterns of eating across chronotypes and assesses tools that have been used to collect data on temporal patterns of eating and chronotype. A systematic search identified thirty-six studies in which aspects of temporal patterns of eating including meal timings; meal skipping; energy distribution across the day; meal frequency; time interval between meals, or meals and wake/sleep times; midpoint of food/energy intake; meal regularity; and duration of eating window were presented in relation to chronotype. Findings indicate that compared to morning chronotypes, evening chronotypes tend to skip meals more frequently, have later mealtimes, and distribute greater energy intake towards later times of the day. More studies should explore the difference in meal regularity and duration of eating window amongst chronotypes. Currently, tools used in collecting data on chronotype and temporal patterns of eating are varied, limiting the direct comparison of findings between studies. Development of a standardised assessment tool will allow future studies to confidently compare findings to inform the development and assessment of guidelines that provide recommendations on temporal patterns of eating for optimal health.

scholarly journals Two maize cultivars of contrasting leaf size show different leaf elongation rates with identical patterns of extension dynamics and coordination

AoB Plants ◽  
2021 ◽  
Author(s):  
Tiphaine Vidal ◽  
Hafssa Aissaoui ◽  
Sabrina Rehali ◽  
Bruno Andrieu
Keyword(s):  
Genotypic Variation ◽  
Leaf Size ◽  
High Rate ◽  
Time Interval ◽  
Extension Rate ◽  
Leaf Production ◽  
Maize Cultivars ◽  
Plant Environment ◽  
The Difference ◽  
Leaf Extension

Abstract Simulating leaf development from initiation to maturity opens new possibilities to model plant–environment interactions and the plasticity of plant architecture. This study analyses the dynamics of leaf production and extension along a maize (Zea mays) shoot to assess important modelling choices. Maize plants from two cultivars originating from the same inbred line, yet differing in the length of mature leaves were used in this study. We characterised the dynamics of the blade and sheath lengths of all phytomers by dissecting plants every 2–3 days. We analysed how differences in leaf size were built up and we examined the coordination between the emergence of organs and phases of their extension. Leaf extension rates were higher in the cultivar with longer leaves than in the cultivar with shorter leaves; no differences were found in other aspects. We found that (i) first post-embryonic leaves were initiated at a markedly higher rate than upper leaves; (ii) below ear position, sheaths were initiated at a time intermediate between tip emergence and appearance, while above the ear position, sheaths were initiated at a high rate, such that the time interval between the blade and sheath initiations decreased for these leaves; and (iii) ear position also marked a change in the correlation in size between successive phytomers with little correlation of size between upper and lower leaves. Our results identified leaf extension rate as the reason for the difference in size between the two cultivars. The two cultivars shared the same pattern for the timing of initiation events, which was more complex than previously thought. The differences described here may explain some inaccuracies reported in functional-structural plant models. We speculate that genotypic variation in behaviour for leaf and sheath initiation exists, which has been little documented in former studies.

High oxidation magmatic evolution in the Naruo porphyry Cu deposit, Tibet, China

2019 ◽  
Vol 76 ◽  
pp. 26-43 ◽  
Author(s):  
Xiangping Zhu ◽  
Duoji ◽  
Guangming Li ◽  
Hongfei Liu ◽  
Huaan Chen ◽  
...  
Keyword(s):  
Magmatic Evolution ◽  
Porphyry Cu ◽  
High Oxidation ◽  
Porphyry Cu Deposit
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