Changes

Jump to navigation Jump to search
260 bytes added ,  16:25, 2 July 2015
no edit summary
Line 9: Line 9:  
This seemingly very easy question may come with a direct answer as easy as: a syncline is the downward arc or curve of a fold. Geology looks at a syncline at a larger perspective than that. A syncline cannot be described without mentioning a fold. A fold, in geology, is a bend in a rock layer caused by forces within the crust of the earth. The forces that cause folds range from slight differences in pressure in the earth’s crust, to large collisions of the crust’s tectonic plates. (Microsoft ® Encarta ® 2007. © 1993-2006 Microsoft Corporation. All rights reserved).These tectonic forces are usually compressions within the earth crust and vary in magnitude and intensity from place to place, producing a wave-like or undulating pattern or structure.This varying compressing forces equally results to differences in size of folds, that is, some folds may be a few centimeters thick while some several meters or more like the syncline at the Canadian Arctic on Ellesmere Island. A fold if “undisturbed” by events such as tilting, faulting among others should have its crown or crest as the anticline and the trough of its structures as the syncline. The anticlinal and synclinal features of a fold usually go hand in hand, and the nature of their shape, position and occurrences determines their name designated to each fold structure. Folds are easily seen after being exposed by erosion.
 
This seemingly very easy question may come with a direct answer as easy as: a syncline is the downward arc or curve of a fold. Geology looks at a syncline at a larger perspective than that. A syncline cannot be described without mentioning a fold. A fold, in geology, is a bend in a rock layer caused by forces within the crust of the earth. The forces that cause folds range from slight differences in pressure in the earth’s crust, to large collisions of the crust’s tectonic plates. (Microsoft ® Encarta ® 2007. © 1993-2006 Microsoft Corporation. All rights reserved).These tectonic forces are usually compressions within the earth crust and vary in magnitude and intensity from place to place, producing a wave-like or undulating pattern or structure.This varying compressing forces equally results to differences in size of folds, that is, some folds may be a few centimeters thick while some several meters or more like the syncline at the Canadian Arctic on Ellesmere Island. A fold if “undisturbed” by events such as tilting, faulting among others should have its crown or crest as the anticline and the trough of its structures as the syncline. The anticlinal and synclinal features of a fold usually go hand in hand, and the nature of their shape, position and occurrences determines their name designated to each fold structure. Folds are easily seen after being exposed by erosion.
   −
[[fig 1]]
+
[[File:UI_Synclines_Fig_2.png|Thumb|300px|{{figure number|1}}1A diagram showing the structure of a fold (Courtesy wikipedia)]]
    
With all the above explained, a syncline may now be described as a part of a fold which has the youngest bed of the strata in its core or center of the structure which has been folded. This is the best term used to describe it rather than “downward arc or trough of a fold” this is because due to events when strata has been overturned, a syncline could arch upwards, this type of synclines are called “antiformal synclines”. So in order words, a syncline is identified by the younger rocks at it’s core. In folds, crests and troughs are usually firstly referred to as synforms and antiforms until the age of the rocks are known.
 
With all the above explained, a syncline may now be described as a part of a fold which has the youngest bed of the strata in its core or center of the structure which has been folded. This is the best term used to describe it rather than “downward arc or trough of a fold” this is because due to events when strata has been overturned, a syncline could arch upwards, this type of synclines are called “antiformal synclines”. So in order words, a syncline is identified by the younger rocks at it’s core. In folds, crests and troughs are usually firstly referred to as synforms and antiforms until the age of the rocks are known.
   −
[[Fig 2]]
+
[[File:UI_Synclines_Fig_2.png|Thumb|300px|{{figure number|2}}A fold showing anticlines and synclines at an outcrop at Eruku city,kwara state, Nigeria.]]
    
==Synclines and  the environment==
 
==Synclines and  the environment==

Navigation menu