Orthopyroxene, augite, and plagioclase compositions in dacite: application to bedrock sourcing of lithic artefacts in southern British Columbia

2004 ◽  
Vol 41 (6) ◽  
pp. 711-723 ◽  
Author(s):  
John D Greenough ◽  
Leanne M Mallory-Greenough ◽  
James Baker

Extremely fine-grained, hypocrystalline, microporphyritic dacite (whole-rock SiO2 = 65–70 oxide wt.%), called "glassy basalt" by archaeologists, was commonly used to manufacture lithic artefacts found in the British Columbia (B.C.) Interior. Geochemical fingerprinting of dacite minerals can help identify the geologic source of these artefacts. Multiple (~300) mineral analyses show that mafic orthopyroxene (En65–80), plagioclase (An30–70), augite (Wo30–45, En40–45, Fs10–15), and olivine (~Fo85) (in that order) represent the most abundant and commonly occurring microphenocrysts. Relative abundances vary among sources. Clustering of averaged mineral data reveals at least five distinct dacite sources for lithic artefacts in the B.C. Interior. Discriminant analysis separates individual mineral analyses according to these five areas with ~ 90% efficiency and provides functions for "sourcing" new artefacts in the future. Two sites represent "quarry" locations and their scope (e.g., geographic area ≥ 4 km2, archaeological stratigraphic depth locally ≥ 2 m at Cache Creek) implies prolonged use and trade. However, fingerprinting suggests that in the B.C. Interior, tools were made from local dacite. Mineral fingerprinting uses small (~0.1 g) samples, which is important when analyzing valuable artefacts. Hypocrystalline, "knappable," microporphyritic dacite is probably common around the Pacific due to Cenozoic subduction. Thus, mineral-based sourcing could have wider application outside of western Canada.

1975 ◽  
Vol 13 (1) ◽  
pp. 90
Author(s):  
Murray F. Mackintosh

In these times of rapidly escalating prices for resources, the provinces of Western Canada have turned their attention to extracting from the resource industry higher return for the citizens in an attempt to provide for the future when the resources are near depletion. This phenomenon is especially noticeable in Alberta. In this article Mr. Mackintosh discusses mineral taxation laws in Alberta and compares them with the corresponding laws of Saskatchewan and British Columbia. The author discusses the constitutionality and interpretation of the new mineral taxation laws and raises some specific problems in applying the legislation.


1996 ◽  
Vol 74 (1) ◽  
pp. 51-59 ◽  
Author(s):  
Donald M. Britton ◽  
Daniel F. Brunton

A new interspecific Isoetes hybrid, I. echinospora Dur. ×I. maritima Underw., is described from Vancouver Island, British Columbia and southern Alaska by means of cytology and the scanning electron microscopy of spores. Isoetes ×pseudotruncata D.M. Britton and D.F. Brunton, hyb.nov. is the name proposed for this taxon. It is triploid and produces only aborted, sterile spores and has spore ornamentation features intermediate between those of its putative parents. Several concentrations of hybrids have been identified, each growing with both parents in shallow, freshwater habitat along the Pacific Coast of northwestern North America. Keywords: Isoetes echinospora, Isoetes maritima, hybrid, British Columbia.


1975 ◽  
Vol 12 (3) ◽  
pp. 489-502 ◽  
Author(s):  
J. A. Westgate ◽  
R. J. Fulton

The Olympia interglacial sediments in the Interior Plateau region of British Columbia contain several thin, fine-grained rhyolitic and dacitic tephras, which undoubtedly represent the distal portions of widespread air-fall eruptive units. Successful discrimination of these tephras can be made by their mineral assemblage and composition of glass, magnetite and ilmenite, as determined by use of an electron microprobe; positive identification is not possible solely on the basis of field criteria such as coloration, degree of weathering, granulometry, thickness and stratigraphic position.Each tephra layer serves as a valuable time-parallel stratigraphic marker because of its regional extent and distinctive character. Those documented in this study include, in order of increasing age: Rialto Creek tephra, about 20 000 years old; Cherryville tephra, about 25 000 years old; Riggins Road tephra, about 30 000 years old; Duncan Lake tephra, about 34 000 years old; Dufferin Hill and Sweetsbridge tephras are probably close in age to Duncan Lake tephra; Kamloops Lake tephra is slightly older than 34 000 years; Mission Flats tephra is probably older than 35 000 years; Coutlee tephra is more than 37 000 years old; and the exact age of Okanagan Centre tephra is unknown. Such a detailed tephrochronological record should greatly facilitate geochronological and correlation studies of Olympia interglacial sediments in south-central British Columbia and adjacent areas of the Pacific Northwest.No definitive statement can be made at present on the identity of source volcanoes, but it is very likely that the commungtonite-rich tephras are derived from Mount St. Helens in Washington State.


2020 ◽  
Author(s):  
Donna Rose Addis

Mental time travel (MTT) is defined as projecting the self into the past and the future. Despite growing evidence of the similarities of remembering past and imagining future events, dominant theories conceive of these as distinct capacities. I propose that memory and imagination are fundamentally the same process – constructive episodic simulation – and demonstrate that the ‘simulation system’ meets the three criteria of a neurocognitive system. Irrespective of whether one is remembering or imagining, the simulation system: (1) acts on the same information, drawing on elements of experience ranging from fine-grained perceptual details to coarser-grained conceptual information and schemas about the world; (2) is governed by the same rules of operation, including associative processes that facilitate construction of a schematic scaffold, the event representation itself, and the dynamic interplay between the two (cf. predictive coding); and (3) is subserved by the same brain system. I also propose that by forming associations between schemas, the simulation system constructs multi-dimensional cognitive spaces, within which any given simulation is mapped by the hippocampus. Finally, I suggest that simulation is a general capacity that underpins other domains of cognition, such as the perception of ongoing experience. This proposal has some important implications for the construct of ‘MTT’, suggesting that ‘time’ and ‘travel’ may not be defining, or even essential, features. Rather, it is the ‘mental’ rendering of experience that is the most fundamental function of this simulation system, enabling humans to re-experience the past, pre-experience the future, and also comprehend the complexities of the present.


1957 ◽  
Vol 89 (1) ◽  
pp. 1-5 ◽  
Author(s):  
J. D. Gregson

Tick paralysis continues to be one of the most baffling and fascinating tickborne diseases in Canada. It was first reported in this country by Todd in 1912. Since then about 250 human cases, including 28 deaths, have been recorded from British Columbia. Outbreaks in cattle have affected up to 400 animals at a time, with losses in a herd as high as 65 head. Although the disease is most common in the Pacific northwest, where it is caused by the Rocky Mountain wood tick, Dermacentor andersoni Stiles, it has lately been reported as far south as Florida and has been produced by Dermacentor variabilis Say, Amblyomma maculatum Koch, and A. americanum (L.) (Gregson, 1953). The symptoms include a gradual ascending symmetrical flaccid paralysis. Apparently only man, sheep, cattle, dogs, and buffalo (one known instance) are susceptible, but even these may not necessarily be paralysed.


Thesis Eleven ◽  
2018 ◽  
Vol 145 (1) ◽  
pp. 77-98 ◽  
Author(s):  
Jose Jowel Canuday

In popular imagery, the littorals of Sulu and Zamboanga conjure visions of pirates, terrorists, and bandits marauding its rough seas, open shores, and rugged mountains. These bleak accounts render the region nothing but a violent and peripheral southern Philippine backdoor inconspicuous to the sophisticated constituencies of the world’s metropolitan centres. Obscured from these imageries are the lasting cosmopolitan traits of openness, flexibility, and reception of local folk to trans-local cultural streams that marked Sulu and Zamboanga as a globalised space across the ages and oceans. The distinctive features of these cosmopolitan sensibilities are strikingly discernible in inter-generationally shared narratives, artefacts, and performances that were continually renewed from the days when Sulu and Zamboanga served as a borderless trading and cultural enclave nestled at the crossroads of the Pacific and the Indian Oceans. These enduring cosmopolitan sensibilities are embodied in the blending, among others, of the time-honoured dance of pangalay and the pop-musical dance genre celebrated on actual, analogue, and digitally-mediated spaces of the contemporary world. Furthermore, these embodied sensibilities are evident in song compositions that proclaim the humanistic themes of hope, peace, and prosperity to their place and the world in ways that exemplify the local people’s broader sense of connections beyond the narrow association of family, community, ethnicity, religion, and identity. This mixed bag of age-old and recent imaginaries and cultural traffic evoke a sociality that link the social spaces of the troubled but once and current globalised region to continuing acts of transcendence in history, memory, and visions of the future. In these marginalized places, we can see an unyielding tradition of cultural re-adaptation and creativity made up of myriad everyday acts that are down-to-earth, pragmatic, interstitial, and practical cosmopolitanism.


Author(s):  
Nguyen Le Thy Thuong ◽  
Nguyen Thi Oanh

The Indo-Pacific region is an area adjacent to some oceans and the gateway that connects the great power and small countries to the world; this region is always considered by Vietnam as a key strategic geographic area, having direct impacts on national security, position and its role in this region. While big powers have different perceptions to the Indo-Pacific region, as a country occupying an important geographic position in the Pacific region, Vietnam shares a common vision of an open and rule-based area, and a common interest in maintaining peace, stability and prosperity as well as building a common space for coexistence and development with the belief that the Indo-Asian-Pacific is large enough for every nation to grow and prosper. This article finds out that recent changes in the Indo-Pacific region in geopolitics, economics, security and national defence have made many countries, including Vietnam, to redefine their global and regional policies to refresh their strategic perceptions. Vietnam has its own perception, position, approach and national orientations, which is shaping its state behaviour and perspectives in this geopolitical vibrant Indo-Pacific region. Besides, this article uses the SWOT analysis model to determine the challenges, strengths and weaknesses of Vietnam in the Indo-Pacific region. Moreover, while the future of the Indo-Pacific in a post-COVID-19 pandemic world remains filled with uncertainty and economic challenges, the crisis also presents an opportunity for Vietnam to re-evaluate its position. Today, Vietnam always maintains its foreign policy of independence, self-reliance, multilateralism and diversification of international relations, which attaches great importance to enhancing multi-faceted cooperation with countries in the Indo-Pacific region. Thus, with its own perception and geostrategic advantage, Vietnam—a developing country in the region and in the world with relatively stable economic growth, pursuing rules and order will be a positive factor for a stable, peaceful and prosperous development in the region.


2006 ◽  
Vol 120 (2) ◽  
pp. 163
Author(s):  
George W. Douglas ◽  
Jenifer L. Penny ◽  
Ksenia Barton

In Canada, Dwarf Woolly-heads, Psilocarphus brevissimus var. brevissimus, is restricted to the Similkameen River valley, south of Princeton in southwestern British Columbia and the extreme southeast and southwest corners of Alberta and Saskatchewan, respectively. This paper deals with the three British Columbia populations which represent the northwestern limit of the species which ranges from south-central British Columbia, southward in the western United States to Montana, Idaho, Washington, Oregon, Nevada, Utah, Wyoming, California and Baja California, Mexico. In British Columbia, P. brevissimus is associated with calcareous vernal pools and ephemeral pond edges in large forest openings. This habitat is rare in the area the few existing populations could easily be extirpated or degraded through slight changes in groundwater levels, coalbed methane gas drilling, housing development or recreational vehicles.


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