ISSN 1556-6757


SJI 


 

 

 

 

 

 

 

 

 

 
 
 

Volume 1, Issue 1, 2009

 
 

The Zumberge Ice Shelf
Nolan B. Aughenbaugh

Abstract

During the maximum of Pleistocene glaciation in the northern hemisphere, the greatest extent of the ice-sheet boundaries has been portrayed as ending at the present continental shorelines. Maps show the Labrador, Greenland, Iceland and Eurasian ice sheets as separate masses. The author proposes that these ice sheets coalesced to form one large ice sheet as presently exists in Antarctica. It is proposed that the southern extent of this ice sheet into the Atlantic Ocean was a floating glacier known as an ice shelf similar to those that exist in Antarctica. This ice shelf, the proposed Zumberge Ice Shelf, was continuous from the United States near Long Island to Great Britain. This distance is no greater than the seaward lengths of the Ross and Ronne-Filchner Ice Shelves in Antarctica. Data from Arctic research findings in the northern Atlantic are presented to support the Zumberge Ice Shelf existence. Recent archeological findings in the eastern United States have found that some of the earliest people to colonize North America were from France and Spain. The Zumberge Ice Shelf would provide an easy, safe and rapid way to make the journey, rather than the use of open boats made of animal skins to cross some 3,000 miles of the stormy North Atlantic Ocean.  Full Article




Sedimentology and paleogeography of the Bakhtyari Conglomeratic Formation at Ghalat and Garu –Charmakan Mountains, NW of Shiraz, Iran,  Mohammad Bahrami

Abstract

Conglomerate – the lithified equivalent of gravel - forms nearly the whole Bakhtyari Formation, and alternates with sandstone and mudstone in the upper parts of the Aghjari Formation in the Folded Zagros Zone, and hence in the studied region. In addition to some low and high anticlines, the region consists of two elevated synclines reaching to over 3000 meters. The synclines are parallel to each other and, unlike in most of the Folded Zagros, overhang adjacent anticlines. Polymictic conglomerates form excellent outcrops in the central parts of these
synclines. From the viewpoint of its (coarse) clast composition, the Bakhtyari Formation consists of two types of conglomerates: 1. Limestone-Chert Clast-Supported Conglomerate (LCCSC) and 2. Limestone Clast-Supported Conglomerate (LCSC). The chronological and spatial relationships between these conglomerates are not easily determined due to existence of some thrust faults at their approximate boundaries, and it seems that each has its own independent chronological and spatial setting. In the vertical succession, various lithofacies are recognized; their textural characteristics and sedimentary structures specify a non-marine depositional system and are considered "standard" lithofacies of alluvial fans and braided rivers. Epirogenic movements in the region began in the Oligocene, indicated by a chert micro-conglomerate bed at the Jahrum – Asmari Formation boundary. These movements then changed to orogenic ones with the deposition of gravelly alluvium now known as Aghajari (upper parts) and Bakhtyari Formations.  Full Article