scholarly journals Provenance Studies of the Ballast Stones found in the North Bay of Tel Dor, Israel

2020 ◽  
Author(s):  
Amanda Holdeman
Keyword(s):  
1994 ◽  
Vol 34 (1) ◽  
pp. 320
Author(s):  
D. J. Whitford ◽  
P.J. Hamilton ◽  
J. Scott

An understanding of the tinting of basin evolution is fundamental to the development of successful play concepts. The Sm-Nd geochronometer can be used to determine quantitatively the `average' age at which segments of continental crust have been extracted from the earth's mantle. Variations in Nd model ages within sedimentary rock sequences indicate changes in sedimentary provenance over time and provide a potential correlation tool.In the Eromanga Basin, there is a distinct lithological contrast between the main reservoir unit, the Jurassic Hutton Sandstone, and the overlying Birkhead Formation. The quartz-rich Hutton Sandstone is characterised by relatively old Nd model ages, generally within the range 1.3–1.5 Ga. In contrast the lithic-rich Birkhead Formation has much younger model ages, generally Neodymium model ages measured in mudstones within the Flag Sandstone from the Harriet Field in the Barrow Sub-basin of the North West Shelf, range from 2.1–2.5 Ga. The old ages are consistent with the sediments being derived from the Archaean shield areas and the younger Proterozoic complexes of Western Australia. Tentative correlations based on model ages between mudstone units from two wells are consistent with correlations based on heavy mineral suites.Neodymium model ages have application to correlation at both regional and local scales within basins. Reliable information can be obtained on both sandstones and mudstones on samples as small 50 g. Potentially they can provide important quantitative information complementary to that derived from more conventional approaches.


2005 ◽  
Vol 84 (2) ◽  
pp. 77-85 ◽  
Author(s):  
R.J.O. Hamblin ◽  
B.S.P. Moorlock ◽  
J. Rose ◽  
J.R. Lee ◽  
J.B. Riding ◽  
...  

AbstractMapping combined with till provenance studies have resulted in a re-appraisal of the pre-Devensian glacial stratigraphy of Norfolk, England. The traditional model invoked two formations, a North Sea Drift Formation (NSDF) overlain by a Lowestoft Formation, formed by co-existing ice-sheets originating in Scandinavia and Northern Britain respectively. The NSDF included three diamictons, the First, Second and Third Cromer tills. The Briton’s Lane Sands and Gravels were considered to overlie the Lowestoft Formation. However, our work has shown this stratigraphy to be untenable, and we propose a model of several glaciations instead of co-existing ice-sheets. In our revised stratigraphy, the oldest formation, the Happisburgh Formation (including the Happisburgh or First Cromer Till) includes massive, sandy tills derived from northern Britain. The overlying Lowestoft Formation, including the Second Cromer (Walcott) Till is confirmed as derived from the west, introducing much Jurassic material as well as Chalk. The Sheringham Cliffs Formation includes both brown sandy tills (the Third Cromer Till) and ‘marly drift’, in a variety of tectonic relationships, and derived from the north and NNW. Finally the Briton’s Lane Formation is the only formation to include Scandinavian erratics. Dating of the four formations is at varying levels of confidence, with the Lowestoft Formation most confidently confirmed as MIS 12. The Happisburgh Formation is believed to represent an earlier glaciation, and MIS 16 is proposed. The Sheringham Cliffs Formation is tentatively believed to date from MIS 10, and the Briton’s Lane Formation is assigned to MIS 6.


2005 ◽  
Vol 7 ◽  
pp. 1-7
Author(s):  
Kai Sørensen

The Review of Survey activities presents a selection of 18 papers reflecting the wide spectrum of activities of the Geological Survey of Denmark and Greenland, from the microbial to the plate tectonic level.Activities in Denmark: The Survey's activities in Denmark are documented by 11 papers. The main themes are petroleum- and groundwater-related topics and Quaternary geology but neotectonics of the Baltic Shield and new methods in provenance studies of sandstones are also touched upon.Activities in Greenland: The Survey's activities in Greenland and the North Atlantic are covered by six articles focusing on climate research, the mineral potential of the Precambrian basement terranes in West Greenland and on the possibility of exploiting dimension stones.Other countries: During 2004, the Survey carried out work in more than 20 countries outside Denmark, Greenland and the Faroe Islands. In this report a project on developing small-scale mining in Mongolia and Kyrgyzstan is described.


Author(s):  
J. Anthony VanDuzer

SummaryRecently, there has been a proliferation of international agreements imposing minimum standards on states in respect of their treatment of foreign investors and allowing investors to initiate dispute settlement proceedings where a state violates these standards. Of greatest significance to Canada is Chapter 11 of the North American Free Trade Agreement, which provides both standards for state behaviour and the right to initiate binding arbitration. Since 1996, four cases have been brought under Chapter 11. This note describes the Chapter 11 process and suggests some of the issues that may arise as it is increasingly resorted to by investors.


2000 ◽  
Vol 179 ◽  
pp. 201-204
Author(s):  
Vojtech Rušin ◽  
Milan Minarovjech ◽  
Milan Rybanský

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.


Author(s):  
Taber A. Ba-Omar ◽  
Philip F. Prentis

We have recently carried out a study of spermiogenic differentiation in two geographically isolated populations of Aphanius dispar (freshwater teleost), with a view to ascertaining variation at the ultrastructural level. The sampling areas were the Jebel Al Akhdar in the north (Group A) and the Dhofar region (Group B) in the south. Specimens from each group were collected, the testes removed, fixed in Karnovsky solution, post fixed in OsO, en bloc stained with uranyl acetate and then routinely processed to Agar 100 resin, semi and ultrathin sections were prepared for study.


Author(s):  
Daryl A. Cornish ◽  
George L. Smit

Oreochromis mossambicus is currently receiving much attention as a candidater species for aquaculture programs within Southern Africa. This has stimulated interest in its breeding cycle as well as the morphological characteristics of the gonads. Limited information is available on SEM and TEM observations of the male gonads. It is known that the testis of O. mossambicus is a paired, intra-abdominal structure of the lobular type, although further details of its characteristics are not known. Current investigations have shown that spermatids reach full maturity some two months after the female becomes gravid. Throughout the year, the testes contain spermatids at various stages of development although spermiogenesis appears to be maximal during November when spawning occurs. This paper describes the morphological and ultrastructural characteristics of the testes and spermatids.Specimens of this fish were collected at Syferkuil Dam, 8 km north- west of the University of the North over a twelve month period, sacrificed and the testes excised.


1999 ◽  
Vol 249 (4) ◽  
pp. 455-461
Author(s):  
El Hassan El Mouden ◽  
Mohammed Znari ◽  
Richard P. Brown

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