scholarly journals Radiometric Dating of Young and Old Calcrete

Radiocarbon ◽  
1997 ◽  
Vol 40 (2) ◽  
pp. 795-802 ◽  
Author(s):  
Mebus A. Geyh ◽  
Bernhard Eitel

To obtain a better understanding of the relationship between calcrete genesis and the results of different absolute dating methods, thermoluminescence (TL), radiocarbon (14C) and uranium/thorium (U/Th) were applied to coeval sample; take from a very young calcrete profile in Namibia. The methodically different ages reflect the characteristics of the applied dating methods, the genetics of calcrete and different events of calcrete genesis. The conventional 14C ages and the TL dates cover the last 50 ka, while the corresponding U/Th dates of coeval samples are many times larger, Uranium-series dates are not related to the deposition of the host material or to its cementation if the ages are smaller than ca. 120 ka. The TL clock is set to zero during eolian transport and the corresponding radiometric ages of the quartz and feldspar grains date the time of their deposition. The 14C ages of the cement correspond, on the other hand, to a time shortly after the onset of the cementation and long before its termination. In the case of very old calcrete, the mixture of young and old cement results in ambiguous ages if they cannot be confirmed by an independent technique.

1972 ◽  
Vol 47 ◽  
pp. 43-54
Author(s):  
L. B. Ronca

Fundamental parameters of the geomorphology of a lunar surface are (i) the number and size distribution of craters, (ii) the degree of erosion of the craters and (iii) thickness and other characteristics of the regolith. These parameters are not independent of one another; as one changes through time, the other two will also change in a statistically predictable way.In the continuous degradation sequence, the relationship between the number of craters per unit area and the degree of erosion of the craters is continuous and monotonic. This sequence occurs in areas subjected to intermediate to small impacts, and eroded mainly by the impacts themselves plus other small-scale erosional processes. In areas subjected to large impacts and mare flooding the discontinuous degradation sequence is predominant.The relationship of the first two parameters, the number of craters and the degree of erosion, with the third parameter, the regolith, is not simple and is not yet understood. It appears, however, that the geomorphological stage is more important than the mare-versus-highland dichotomy of the lunar surface.The solution of the function relating craters of the continuous degradation sequence with degree of erosion was defined as the geomorphic index of the area. Studies of the geomorphic index of stratigraphic surfaces show that areas covered by considerable ballistic sediments have a geomorphic index which is not a monotonic function of time. On the other hand, areas covered almost exclusively by mare flooding show an index which is a monotonic function of the age of the flooding. As each mare surface shows a considerable range in indices, it is concluded that maria are covered by surfaces formed through a considerable length of time. By using Apollo 11 and 12 radiometric ages it is suggested that the time of mare flooding lasted on the order of one billion (109) years.The geomorphic index of highland surfaces shows a remarkable degree of order; i.e., the farther an area is inland from the mare shores, the higher will be the index. No explanation is given to this phenomenon, but is suggested that lunar erosion is not just a localized phenomenon centered on the locus of an impact, but has lateral trends of regional dimensions. Electrostatic transportation as suggested by Gold is a possible mechanism.


Clay Minerals ◽  
2018 ◽  
Vol 53 (3) ◽  
pp. 305-324 ◽  
Author(s):  
Peter Vrolijk ◽  
David Pevear ◽  
Michael Covey ◽  
Allan LaRiviere

ABSTRACTRadiometric dating of fault gouges has become a useful tool for regional tectonics studies and for exploring and understanding fault and earthquake processes. Methods to define the absolute age of faults achieved a solid scientific foundation almost 25 years ago when the development and application of illite age analysis for investigating sedimentary burial and thermal histories found a new potential application – defining the age of fold-and-thrust development. Since then, the methods have benefitted from further development and incorporation of the 40Ar/39Ar micro-encapsulation method and quantitative clay mineral evaluation to distinguish polytypes (Wildfire). These refinements to the methods have improved their application in fold-and-thrust terrains and have opened up applications in normal and strike-slip fault environments. Another important development is the use of absolute dating methods in retrograde clay gouges in which clays in a fault develop from igneous or metamorphic wall rocks that contain no clays. In addition, the method has also been shown to be useful at dating folds in fold-and-thrust belts. We think the method is now an established part of the geological toolkit, look forward to future fault structural and tectonic studies that incorporate fault ages and hope that researchers continue to probe and discover ways that the method can assist fault process studies, including earthquake fault studies.


1995 ◽  
Vol 36 (1) ◽  
pp. 87-95 ◽  
Author(s):  
Jiří Veltruský

This article deals with a very short period in the long history of the semiotic conception of theatre. It concentrates on the relationship between the theatrical avantgarde and the theories developed during some twenty years in Czechoslovakia, by Otakar Zich on the one hand and the members of the Prague Linguistic Circle on the other. Broadly speaking, this is the Prague School theory of theatre. A Polish scholar has called it “semiotics of theatre in statu nascendi.” This designation is no doubt pertinent as far as the recent development of the discipline is concerned; its more remote past still remains largely unexplored. But another commentator went much further, claiming that until 1931, the year when Zich's treatise on the theatre and Mukařovský's article on Chaplin's City Lights appeared, “dramatic poetics—the descriptive science of the drama and theatrical performance—had made little progress since its Aristotelian origins.” In fact, semiotics is a very old discipline and the semiotic interpretation of the theatre was not invented in Czechoslovakia between the two World Wars.


Crisis ◽  
2011 ◽  
Vol 32 (5) ◽  
pp. 246-253 ◽  
Author(s):  
Gretchen E. Ely ◽  
William R. Nugent ◽  
Julie Cerel ◽  
Mholi Vimbba

Background: The relationship between suicidal thinking and adolescent dating violence has not been previously explored in a sample of adolescent abortion patients. Aims: This paper highlights a study where the relationship between dating violence and severity of suicidal thinking was examined in a sample of 120 young women ages 14–21 seeking to terminate an unintended pregnancy. Methods: The Multidimensional Adolescent Assessment Scale and the Conflict in Adolescent Relationships Scale was used to gather information about psychosocial problems and dating violence so that the relationship between the two problems could be examined, while controlling for the other psychosocial problems. Results: The results suggest that dating violence was related to severity of suicidal thinking, and that the magnitude of this relationship was moderated by the severity of problems with aggression. Conclusions: Specifically, as the severity of participant’s general problems with aggression increased, the magnitude of the relationship between dating violence and severity of suicidal thinking increased. Limitations of the study and implications for practice are discussed.


Author(s):  
Melanie K. T. Takarangi ◽  
Deryn Strange

When people are told that their negative memories are worse than other people’s, do they later remember those events differently? We asked participants to recall a recent negative memory then, 24 h later, we gave some participants feedback about the emotional impact of their event – stating it was more or less negative compared to other people’s experiences. One week later, participants recalled the event again. We predicted that if feedback affected how participants remembered their negative experiences, their ratings of the memory’s characteristics should change over time. That is, when participants are told that their negative event is extremely negative, their memories should be more vivid, recollected strongly, and remembered from a personal perspective, compared to participants in the other conditions. Our results provide support for this hypothesis. We suggest that external feedback might be a potential mechanism in the relationship between negative memories and psychological well-being.


1994 ◽  
Vol 72 (01) ◽  
pp. 058-064 ◽  
Author(s):  
Goya Wannamethee ◽  
A Gerald Shaper

SummaryThe relationship between haematocrit and cardiovascular risk factors, particularly blood pressure and blood lipids, has been examined in detail in a large prospective study of 7735 middle-aged men drawn from general practices in 24 British towns. The analyses are restricted to the 5494 men free of any evidence of ischaemic heart disease at screening.Smoking, body mass index, physical activity, alcohol intake and lung function (FEV1) were factors strongly associated with haematocrit levels independent of each other. Age showed a significant but small independent association with haematocrit. Non-manual workers had slightly higher haematocrit levels than manual workers; this difference increased considerably and became significant after adjustment for the other risk factors. Diabetics showed significantly lower levels of haematocrit than non-diabetics. In the univariate analysis, haematocrit was significantly associated with total serum protein (r = 0*18), cholesterol (r = 0.16), triglyceride (r = 0.15), diastolic blood pressure (r = 0.17) and heart rate (r = 0.14); all at p <0.0001. A weaker but significant association was seen with systolic blood pressure (r = 0.09, p <0.001). These relationships remained significant even after adjustment for age, smoking, body mass index, physical activity, alcohol intake, lung function, presence of diabetes, social class and for each of the other biological variables; the relationship with systolic blood pressure was considerably weakened. No association was seen with blood glucose and HDL-cholesterol. This study has shown significant associations between several lifestyle characteristics and the haematocrit and supports the findings of a significant relationship between the haematocrit and blood lipids and blood pressure. It emphasises the role of the haematocrit in assessing the risk of ischaemic heart disease and stroke in individuals, and the need to take haematocrit levels into account in determining the importance of other cardiovascular risk factors.


2014 ◽  
pp. 147-153
Author(s):  
P. Orekhovsky

The review outlines the connection between E. Reinert’s book and the tradition of structural analysis. The latter allows for the heterogeneity of industries and sectors of the economy, as well as for the effects of increasing and decreasing returns. Unlike the static theory of international trade inherited from the Ricardian analysis of comparative advantage, this approach helps identify the relationship between trade, production, income and population growth. Reinert rehabilitates the “other canon” of economic theory associated with the mercantilist tradition, F. Liszt and the German historical school, as well as a reconside ration of A. Marshall’s analysis of increasing returns. Empirical illustrations given in the book reveal clear parallels with the path of Russian socio-economic development in the last twenty years.


2020 ◽  
Vol 7 (2) ◽  
pp. 291-317
Author(s):  
Burak Çavuş

Bu çalışmada, 1960-1990 yılları arasında yayınlanan ve Avrupa’ya işçi göçünü konu edinen romanlar izleksel bağlamda incelenmiştir. Romanlardaki temel izlekler çerçevesinde göç süreci irdelenmiş, inceleme, göçmenlerin tanımlanmasında ve adlandırılmasında kullanılan Gastarbeiter (konuk işçi) Auslander (yabancı) kavramları ve Almanlar tarafından Türk kimliğine atfedilen çağrışımlar üzerinden yürütülmüştür. Göçmenlere yönelik politikalarda ve yaklaşımlarda onların nasıl tanımlandığının etkili olduğuna ve yazınsal süreçte de bu politika ve yaklaşımların belirleyici olduğu savından hareket edilmiştir. Bu noktada adlandırmaların, tanımlamaların göç olayı çerçevesinde biz ve öteki ilişkisi üzerindeki etkisine odaklanılmış; toplum ve yazın ilişkisi temelinde incelenen romanlar üzerinden göç ve göçmenlik meselesine dair çıkarımlar yapılmıştır. Bunlar arasında, ayrımcılık, kötü çalışma koşulları, hak ihlalleri, ırkçılık ve ötekileştirme gibi başat sorunların bu eserlerde merkezi konumda olduğu tespit edilmiştir. Böylece çalışmanın amacı olan göç yazınını oluşturan temel izleklere ulaşılmış; sosyolojik ve tarihsel gerçekliğin yazınsal gerçekliğe aktarılmasında etkili olan unsurlar ön plana çıkarılmıştır. ABSTRACT IN ENGLISH Main Patterns in Migration Novels In this study, the novels published between 1960-1990 and dealing with the migration of workers to Europe were examined in a contextual context. The process of immigration has been examined within the framework of the basic lines in the novels, through the concepts of Gastarbeiter (guest worker), Auslander (foreigner) used in the identification and naming of immigrants and connotations attributed to Turkish identity was conducted. The argument is that how they are defined is effective in policies and approaches towards immigrants and that these policies and approaches are determinative in the literary process. At this point, the effect of naming definitions on us and the other relationship within the framework of migration has been focused; there are inferences about the issue of migration and immigration through the novels examined on the basis of the relationship between society and literature. Among these, it has been determined that dominant problems such as discrimination, poor working violations, racism and marginalization are central to these works. Thus, the basic themes that constitute the migration literature, which is the aim of the study have been reached and the factors that are effective in transferring the sociological and historical reality have been brought the fore.


2020 ◽  
Vol 10 (1) ◽  
pp. 59-71
Author(s):  
Perrine Moran

Many couples who come for therapy are struggling with separating from unconscious phantasies and beliefs that enmesh each partner with the other, resulting in states that popular songs powerfully epitomise. While this borderline experience is common and functional in the early stages of being in love its persistence paralyses the development of the relationship. Facing separation from and loss of illusion is a challenge couple therapists are often asked to help with. The argument is illustrated by a case, and by references to some of Cole Porter’s best known songs.


2014 ◽  
Vol 4 (2) ◽  
Author(s):  
Tamara Feldman

This paper is a contribution to the growing literature on the role of projective identification in understanding couples' dynamics. Projective identification as a defence is well suited to couples, as intimate partners provide an ideal location to deposit unwanted parts of the self. This paper illustrates how projective identification functions differently depending on the psychological health of the couple. It elucidates how healthier couples use projective identification more as a form of communication, whereas disturbed couples are inclined to employ it to invade and control the other, as captured by Meltzer's concept of "intrusive identification". These different uses of projective identification affect couples' capacities to provide what Bion called "containment". In disturbed couples, partners serve as what Meltzer termed "claustrums" whereby projections are not contained, but imprisoned or entombed in the other. Applying the concept of claustrum helps illuminate common feelings these couples express, such as feeling suffocated, stifled, trapped, held hostage, or feeling as if the relationship is killing them. Finally, this paper presents treatment challenges in working with more disturbed couples.


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