Growth and Mechanics of Brittle Fault Systems in Rock Mass: An Example of Baihetan Hydropower Dam Area

2014 ◽  
Vol 580-583 ◽  
pp. 883-886
Author(s):  
Wan Qiang Cheng ◽  
Sheng Jie Di ◽  
Xue Yong Xu ◽  
Gang Song

Architectures of fault systems play important role in stability and mechanics of rock mass. While growth mechanism of faults is intrinsic controler for architectures of fault systems. This paper presents a case on faulting in the dam area of an oversized hydropower in Southwestern China. The faults in this area are mostly strike-slip faults with shallow brittle deformation characters, extending tens to hundreds of meters. These faults can be divided into four groups which are formed during two generations corresponds to two periods of tectonic events. Growth model of these faults have been built based on geologic and mechanic data. The first generation of faults was formed based on preexisting joints. While the secondary generation emerge only if the existing faults become critically misaligned during rotation of the primary stresses. The criterion laws for formation of secondary faults are suggested. According to the growth model, we can predict placement of secondary faults in space. Conversely, when geometry and space characters of the fault systems are known, we can estimate mechanic parameters and tectonic environments of the rock mass.

2019 ◽  
Author(s):  
Zac Wylde ◽  
Foteini Spagopoulou ◽  
Amy K Hooper ◽  
Alexei A Maklakov ◽  
Russell Bonduriansky

Individuals within populations vary enormously in mortality risk and longevity, but the causes of this variation remain poorly understood. A potentially important and phylogenetically widespread source of such variation is maternal age at breeding, which typically has negative effects on offspring longevity. Here, we show that paternal age can affect offspring longevity as strongly as maternal age does, and that breeding age effects can interact over two generations in both matrilines and patrilines. We manipulated maternal and paternal ages at breeding over two generations in the neriid fly Telostylinus angusticollis. To determine whether breeding age effects can be modulated by the environment, we also manipulated larval diet and male competitive environment in the first generation. We found separate and interactive effects of parental and grandparental ages at breeding on descendants’ mortality rate and lifespan in both matrilines and patrilines. These breeding age effects were not modulated by grandparental larval diet quality or competitive environment. Our findings suggest that variation in maternal and paternal ages at breeding could contribute substantially to intra-population variation in mortality and longevity.


2020 ◽  
Vol 54 (s41) ◽  
pp. 89-115
Author(s):  
Einat Gonen

Abstract This paper presents a diachronic study of Modern Hebrew agreement between numerals and their quantified nouns. This research is possible thanks to the discovery of two rare collections of recordings from the 1950s and 1960s, which document four generations of speakers and have become important sources of spoken Early Modern Hebrew. On the basis of these two corpora, I compare numeral agreement in the first two generations of speakers with present-day usage and analyze trends of change and conversation in Modern Hebrew. The study shows that the first generation of speakers (“Gen1”) largely acquired the gender distinction of cardinals. However, in contrast to other agreement issues that educated Gen1 speakers realized fully, numeral use showed variation and absence of agreement in a small set of cases. Moreover, some linguistic features of Gen1 Hebrew found in this study no longer characterize Present-Day Hebrew; among these features is prosodic conditioning, which led to a Gen1 tendency to use the feminine form of the numeral ‘four’ with masculine nouns more frequently than was the case with other numerals.


2003 ◽  
Vol 75 (2) ◽  
pp. 235-248 ◽  
Author(s):  
Dilce F. Rossetti

The geological characterization of shallow subsurface Neogene deposits in northeastern Pará State using Ground Penetrating Radar (GPR) revealed normal and reverse faults, as well as folds, not yet well documented by field studies. The faults are identified mostly by steeply-dipping reflections that sharply cut the nearby reflections causing bed offsets, drags and rollovers. The folds are recognized by reflections that are highly undulating, configuring broad concave and convex-up features that are up to 50 m wide and 80 to 90 ns deep. These deformation structures are mostly developed within deposits of Miocene age, though some of the faults might continue into younger deposits as well. Although the studied GPR sections show several diffractions caused by trees, differential degrees of moisture, and underground artifacts, the structures recorded here can not be explained by any of these ''noises''. The detailed analysis of the GPR sections reveals that they are attributed to bed distortion caused by brittle deformation and folding. The record of faults and folds are not widespread in the Neogene deposits of the Bragantina area. These GPR data are in agreement with structural models, which have proposed a complex evolution including strike-slip motion for this area from the Miocene to present.


1986 ◽  
Vol 118 (4) ◽  
pp. 351-359 ◽  
Author(s):  
M.T. AliNiazee

AbstractSeasonal history, adult flight activity, and damage of the obliquebanded leafroller, Choristoneura rosaceana (Harris), on filbert were studied during a 7-year period between 1976 and 1984. Data from periodic field counts and moth catches in sex-attractant traps indicated two generations per year. The first-generation adult capture peak was generally higher than the second, except in 1978 when about an equal number of moths were trapped from both generations. A physiological time scale, using degree-days (DD), was devised for predicting emergence of obliquebanded leafroller adults. The first adults from overwintering larvae emerged at approximately 374 DD above a threshold of 10 °C starting 1 March. A total of 1172 DD were required between the first and the last adult emergence during the first generation and about 519 DD during the second generation. The obliquebanded leafroller causes both foliar and nut damage in filbert orchards of Oregon. Foliar damage was insignificant, but nut damage, caused exclusively by the first-generation larvae during June and early July, was highly destructive. Larval feeding on nuts caused staining and premature drop of infested nuts resulting in substantial yield reduction in heavily infested orchards.


2013 ◽  
Vol 47 (1) ◽  
pp. 438 ◽  
Author(s):  
I. Thabet ◽  
A. Kilias ◽  
A. Koroneos ◽  
S. Kamh

The study deals with the petrography of the granitoid rocks intruding the five (A to E) domes of Hafafit Culmination. The morphological characteristics of zircon crystals are also examined, in order to elucidate the genesis of zircon and their host Hafafit granitoids. The granitoid rocks are tonalites, granodiorites and quartz diorites, all exhibiting gneissic texture. The zircon crystals from all the rock types intruding each one of the domes are examined in detail for colour, inclusions, crystal length, crystal width, elongation ratio, crystal form and habit, degree of roundness and corrosion, and are distinguished in groups on the basis of the previous characteristics. Two generations of zircons have been recognized; the first generation with magmatic features and the second one with post magmatic features. The first generation of zircon is attributed to the subduction, magmatic and deformation events while the second generation of zircon is attributed to metamorphism.


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