Tectonic controls of the time-space distribution of some Proterozoic metal deposits

1983 ◽  
pp. 179-190 ◽  
Author(s):  
Frederick J. Sawkins
Keyword(s):  
Space Distribution ◽  
Time Space

scholarly journals Precambrian faulting episodes and insights into the tectonothermal history of North Australia: Microstructural evidence and K–Ar, <sup>40</sup>Ar–<sup>39</sup>Ar, and Rb–Sr dating of syntectonic illite from the intracratonic Millungera Basin

2020 ◽  
Author(s):  
I. Tonguç Uysal ◽  
Claudio Delle Piane ◽  
Andrew Todd ◽  
Horst Zwingmann
Keyword(s):  
Large Scale ◽  
Active Tectonics ◽  
Mineral Resources ◽  
Sedimentary Basins ◽  
Integrated Approach ◽  
Space Distribution ◽  
Seismic Survey ◽  
North Central ◽  
Time Space ◽  
Central Australia

Abstract. Australian terranes concealed beneath Mesozoic cover record complex Precambrian tectonic histories involving a successive development of several Proterozoic to Paleozoic orogenic systems. This study presents an integrated approach combining K–Ar, 40Ar–39Ar, and Rb–Sr geochronology of Precambrian authigenic illites from the recently discovered Millungera Basin in north-central Australia. Brittle deformation and repeated fault activity are evident from the sampled cores and their microstructures, probably associated with the large-scale faults inferred from interpretations of seismic survey. Rb–Sr isochron, 40Ar–39Ar total gas, and K–Ar ages are largely consistent indicating late Mesoproterozoic and early Proterozoic episodes (~ 1115 ± 26 Ma, ~ 1070 ± 25 Ma, ~ 1040 ± 24 Ma, ~ 1000 ± 23 Ma, and ~ 905 ± 21 Ma) of active tectonics in north-central Australia. K–Ar results show that illites from fault gouges and authigenic matrix illites in undeformed adjacent sandstones precipitated contemporaneously, indicating that advection of tectonically mobilised fluids extended into the undeformed wall rocks above or below the fracture and shear (fault gouge) zones. This study provides insight into the enigmatic time-space distribution of Precambrian tectonic zones in central Australia, which are responsible for the formation of a number of sedimentary basins with significant energy and mineral resources.

scholarly journals Differential Distribution Analysis and Region and Grade Regulation on Auto-Parts Weathering External Factors with Non-Uniform Thermal Environment

2020 ◽  
Vol 10 (15) ◽  
pp. 5116
Author(s):  
Zhiyong Deng ◽  
Fengchong Lan ◽  
Jiqing Chen
Keyword(s):  
Thermal Environment ◽  
External Factors ◽  
Space Distribution ◽  
Physical Parameters ◽  
Distribution Analysis ◽  
Differential Distribution ◽  
Time Space ◽  
Auto Parts ◽  
Numerical Calculation Method ◽  
Outdoor Weathering

It is difficult to comprehensively master and precisely regulate the external factors distribution of automobile weathering in non-uniform thermal environment as well as the consequent disequilibrium weathering problem, while exploring weather-resistant materials in uniform thermal environment. Thus, a numerical calculation method for the weathering external factors is proposed, on the basis of annual experimental study on the outdoor weathering inconsistencies of auto-parts. The time–space distribution characteristics and day–night variation rules of the external factors are studied, and the disequilibrium weathering mechanism among parts is revealed from the perspective of non-uniform distribution of external factors. The laws of automotive physical parameters, orientations and locations, as well as their influences on external factors distribution are analyzed in detail, and hereby the targeted schemes to effectively reduce the local external factor intensity and the thermal gradient between parts are investigated. The method can be used to rapidly predict weathering external factors distribution of vehicle exposed to outdoor in any direction during day and night, so as to provide auto-parts with differentiated test schemes in accelerated tests and IP/DP box tests, and it also contributes to present some pertinence guidance for the accurate regulation of automobile disequilibrium weathering on regions at different levels.

Grossplots: a Method for Estimating the Temperature State of the Earth and of Australia, Cretaceous to Middle Miocene

1997 ◽  
Vol 45 (3) ◽  
pp. 359 ◽  
Author(s):  
L. A. Frakes
Keyword(s):  
Middle Miocene ◽  
Global Climate ◽  
Interval Data ◽  
Late Eocene ◽  
Space Distribution ◽  
Mean Annual Temperature ◽  
The North ◽  
Early Oligocene ◽  
Time Space ◽  
Temperature State

Grossplots are compilations of globally distributed palaeotemperature data onto latitude versus age plots, which are then contoured. The results specifically show the distribution of temperature over the globe and its variations over the Cretaceous to Middle Miocene interval. Data for continents and oceans are plotted separately in this investigation, and each such grossplot is in accord with the known climate changes of this time. The general scarcity of quantitative palaeotemperature information for Australia can be rectified by deriving, from the global continental grossplot, the relationship between mean annual temperature and latitude. When these are applied to the latitude band progressively occupied by Australia, the following observations can be made: (1) during the Early Cretaceous, the south-east of the continent was subjected to freezing wintertime temperatures; (2) peak warming of northern Australia was attained in the Turonian–Santonian, but this was followed by cooling later in the Cretaceous; (3) Early Tertiary warming until the Late Eocene particularly affected the northern half of the continent, but this region then underwent the most severe cooling in the Early Oligocene; (4) subsequently, the whole of the continent cooled uniformly from conditions only slightly warmer than at present. Despite Australia’s equatorward march, the Late Cretaceous to Palaeocene climates of the continent have been influenced more effectively by changes in the global climate state. However, global cooling since the Eocene has been less effective than drift in controlling the warming climate of Australia. The time–space distribution of precipitation over Australia is estimated from the global relationship between terrestrial temperature and rainfall. The Eocene experienced the heaviest rainfall (> 1560 mm year-1, in the north only), and the Eocene to Middle Miocene experienced moderately high rates (> 500 mm year-1 in the northern three-quarters of the continent). Tertiary brown coals in southern regions were formed in proximity to areas of high rainfall. Continentwide low rates (< 500 mm year-1; semi-arid) are suggested for the Cretaceous, except for wet conditions in the north during the Albian–Santonian and the Late Maastrichtian. Estimates of precipitation are subject to factors such as continentality and location of moisture sources, which cannot be evaluated at present.

The Role of Epidemiological Investigation in the Detection of Environmental Carcinogenic Risks

1968 ◽  
Vol 54 (1) ◽  
pp. 23-46
Author(s):  
Rodolfo Saracci ◽  
Umberto Veronesi
Keyword(s):  
Large Scale ◽  
Retrospective Studies ◽  
Space Distribution ◽  
Epidemiological Methods ◽  
Laboratory Studies ◽  
Cancer Etiology ◽  
Common Basis ◽  
Time Space ◽  
Morbidity Data

An introductory review is presented of the uses and limitations of epidemiological methods for investigating cancer etiology. Uses of epidemiological methods can be grouped under three main headings: search af etiological indications, test of etiological hypotheses, and assessment of the effect of large scale prophylactic or therapeutic treatments. The search of etiological indications is chiefly performed through an analysis of mortality and/or morbidity data: time and space distribution of cancers are usually studied and sometimes an investigation on time-space association is added. On this basis etiological hypotheses are formulated and tested using retrospective studies and/or prospective studies: typical examples of these are found in oncological literature. Assessment of the effect of large scale prophylactic or therapeutic treatments, where feasible, is a further check on the soundness of an etiological hypothesis. Limitations intrinsic to the epidemiological approach (as to any merely observational approach) can be partly overcome through close linkage between epidemiologic and experimental oncology; use of mathematical models to interpret on a common basis data from epidemiological and laboratory studies can make easier this task.

Major types and time–space distribution of Mesozoic ore deposits in South China and their geodynamic settings

2012 ◽  
Vol 48 (3) ◽  
pp. 267-294 ◽  
Author(s):  
Mao Jingwen ◽  
Cheng Yanbo ◽  
Chen Maohong ◽  
Franco Pirajno
Keyword(s):  
South China ◽  
Ore Deposits ◽  
Space Distribution ◽  
Geodynamic Settings ◽  
Time Space

Types, characteristics, and time–space distribution of molybdenum deposits in China

2013 ◽  
Vol 55 (11) ◽  
pp. 1311-1358 ◽  
Author(s):  
Qingdong Zeng ◽  
Jianming Liu ◽  
Kezhang Qin ◽  
Hongrui Fan ◽  
Shaoxiong Chu ◽  
...  
Keyword(s):  
Space Distribution ◽  
Time Space
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