scholarly journals Tectonostratigraphic evolution of the Orphan Basin and Flemish Pass region – Part 2: Regional structural development and lateral variations in rifting style

2021 ◽  
pp. 105219
Author(s):  
Adam J. Cawood ◽  
David A. Ferrill ◽  
Alan P. Morris ◽  
David Norris ◽  
David McCallum ◽  
...  
1992 ◽  
Author(s):  
MICHAEL LOU ◽  
WALTER TSUHA ◽  
PAUL LARKIN

Author(s):  
Henrik Rasmussen ◽  
Paul Martin Holm

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Rasmussen, H., & Holm, P. M. (1999). Proterozoic thermal activity in the Archaean basement of the Disko Bugt region and eastern Nuussuaq, West Greenland: evidence from K-Ar and 40Ar-39Ar mineral age investigations. Geology of Greenland Survey Bulletin, 181, 55-64. https://doi.org/10.34194/ggub.v181.5113 _______________ K-Ar and 40Ar-39Ar analyses of amphiboles from Archaean amphibolites and gneisses show that Proterozoic tectono-thermal activity has played an important role in the metamorphic and structural development of the Precambrian rocks around north-eastern Disko Bugt and in eastern Nuussuaq. Proterozoic thermal activity lead to resetting of the K-Ar ages of amphiboles in eastern Nuussuaq, resulting in ages of c. 1750 to 1925 Ma; in the Disko Bugt area the effects are seen in total or partial resetting with K-Ar ages scattering mostly between 2750 and 1870 Ma. Resetting is caused either by total diffusion of earlier accumulated radiogenic argon or by complete recrystallisation of the amphiboles. Archaean 40Ar-39Ar ages obtained from mafic xenoliths within the Atâ tonalite show that not all parts of the area suffered argon loss during Proterozoic reheating. Incorporation of significant proportions of excess argon in some amphiboles is seen from 40Ar-39Ar mineral age spectra obtained for samples from supracrustal rocks and from mafic xenoliths in the Atâ tonalite. Phlogopite phenocrysts from a lamproite stock yielded a K-Ar age of 1764 ± 24 Ma, identical to a previously determined K-Ar age of the matrix phlogopite. These ages probably date the emplacement of the lamproite, and mark the time after which no tectono-thermal events affected the area.


2019 ◽  
Author(s):  
Robert D. Jacobi ◽  
◽  
Ryan Mathur ◽  
Ryan Mathur ◽  
Ashley S.B. Douds ◽  
...  

Author(s):  
Walter Mattli ◽  
Miles Kellerman

Advances in telecommunication technology in the nineteenth century encouraged greater centralization of liquidity on single, dominant exchanges in most major industrialized countries. Electronic trading, in contrast, has precipitated increased market fragmentation, creating a host of new regulatory dilemmas. In an attempt to understand this phenomenon, this chapter proposes a two-stage process of market structural development in response to electronic trading. This process is then examined in equities and foreign exchange markets. Despite significant differences between these two asset classes, they have exhibited a remarkably similar pattern of disintermediation followed by reintermediation. This analysis is followed by a survey of recent regulatory approaches to mitigate the negative externalities associated with electronic trading. It concludes with a brief discussion on the future of market fragmentation and centralization in global capital markets.


2016 ◽  
Vol 6 (4) ◽  
pp. 407-425 ◽  
Author(s):  
Yuangsheng Gao ◽  
David N. Cornfield ◽  
Kurt R. Stenmark ◽  
Bernard Thébaud ◽  
Steven H. Abman ◽  
...  

This review summarizes our current knowledge on lung vasculogenesis and angiogenesis during normal lung development and the regulation of fetal and postnatal pulmonary vascular tone. In comparison to that of the adult, the pulmonary circulation of the fetus and newborn displays many unique characteristics. Moreover, altered development of pulmonary vasculature plays a more prominent role in compromised pulmonary vasoreactivity than in the adult. Clinically, a better understanding of the developmental changes in pulmonary vasculature and vasomotor tone and the mechanisms that are disrupted in disease states can lead to the development of new therapies for lung diseases characterized by impaired alveolar structure and pulmonary hypertension.


Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1134
Author(s):  
Bo Seok Song ◽  
Jun Young Lee ◽  
Sun Hwa Jang ◽  
Wan-Gyu Hahm

High-speed melt spinning of thermotropic liquid crystalline polymer (TLCP) resin composed of 4-hydroxybenzoic acid (HBA) and 2-hydroxy-6-napthoic acid (HNA) monomers in a molar ratio of 73/27 was conducted to investigate the characteristic structure development of the fibers under industrial spinning conditions, and the obtained as-spun TLCP fibers were analyzed in detail. The tensile strength and modulus of the fibers increased with shear rate in nozzle hole, draft in spin-line and spinning temperature and exhibited the high values of approximately 1.1 and 63 GPa, respectively, comparable to those of industrial as-spun TLCP fibers, at a shear rate of 70,000 s−1 and a draft of 25. X-ray diffraction demonstrated that the mechanical properties of the fibers increased with the crystalline orientation factor (fc) and the fractions of highly oriented crystalline and non-crystalline anisotropic phases. The results of structure analysis indicated that a characteristic skin–core structure developed at high drafts (i.e., spinning velocity) and low spinning temperatures, which contributed to weakening the mechanical properties of the TLCP fibers. It is supposed that this heterogeneous structure in the cross-section of the fibers was induced by differences in the cooling rates of the skin and core of the fiber in the spin-line.


Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1557
Author(s):  
Farkhod Azimov ◽  
Jihee Kim ◽  
Seong Min Choi ◽  
Hyun Min Jung

α-Fe2O3, which is an attractive material for supercapacitor electrodes, has been studied to address the issue of low capacitance through structural development and complexation to maximize the use of surface pseudocapacitance. In this study, the limited performance of α-Fe2O3 was greatly improved by optimizing the nanotube structure of α-Fe2O3 and its combination with polyaniline (PANI). α-Fe2O3 nanotubes (α-NT) were fabricated in a form in which the thickness and inner diameter of the tube were controlled by Fe(CO)5 vapor deposition using anodized aluminum oxide as a template. PANI was combined with the prepared α-NT in two forms: PANI@α-NT-a enclosed inside and outside with PANI and PANI@α-NT-b containing PANI only on the inside. In contrast to α-NT, which showed a very low specific capacitance, these two composites showed significantly improved capacitances of 185 Fg−1 for PANI@α-NT-a and 62 Fg−1 for PANI@α-NT-b. In the electrochemical impedance spectroscopy analysis, it was observed that the resistance of charge transfer was minimized in PANI@α-NT-a, and the pseudocapacitance on the entire surface of the α-Fe2O3 nanotubes was utilized with high efficiency through binding and conductivity improvements by PANI. PANI@α-NT-a exhibited a capacitance retention of 36% even when the current density was increased 10-fold, and showed excellent stability of 90.1% over 3000 charge–discharge cycles. This approach of incorporating conducting polymers through well-controlled nanostructures suggests a solution to overcome the limitations of α-Fe2O3 electrode materials and improve performance.


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