We use cookies to create the best experience for you. Keep on browsing if you are OK with that, or find out how to manage cookies.
Nobody downloaded yet

How old are the rocks of the Lewisian Complex in NW Scotland, and how do we know - Essay Example

Comments (0) Cite this document
Summary
Several types of rocks are found here, from the oldest high-grade metamorphic rocks of the Scourian episode to those deformed and heated again in the later Laxfordian episode. Around Scourie village the…
Download full paper
GRAB THE BEST PAPER
How old are the rocks of the Lewisian Complex in NW Scotland, and how do we know
Read TextPreview

Extract of sample
How old are the rocks of the Lewisian Complex in NW Scotland, and how do we know

Download file to see previous pages... This was followed by the new rocks folding and heating, and the intrusion of further magmas during the metamorphism, resulting in almost all the rocks being gneisses (Waters, 2003).
The Lewisian Gneiss are a major division of Precambrian rocks (4.6 billion to 542 million years ago) in northwestern Scotland. In the region where the Lewisian rocks are found, they also form the lowermost rocks, also the Outer Hebrides, form the islands of Coll and Tiree, and are exposed along the northwestern coast of Scotland. “The oldest rocks of the Lewisian have been dated by radiometric technique between 2.4 billion and 2.6 billion years old, whereas the youngest Lewisian rocks have been dated at 1.6 billion years (Encyclopedia Britannica, 2010). Further, the Lewisian Complex form the oldest rocks of the British Isles, and are Mid- to Late- Archaen in age (Jones15). Most of these rocks are deformed and metamorphosed igneous rocks or orthogneisses.
The types of rocks found in the Lewisian Comples are broadly subdivided into felsic gneisses which have a high content of light coloured minerals, mafic gneisses with a large proportion of dark mafic minerals, and ultramafic gneisses containing purely mafic minerals. Usually, the most highly abundant felsic gneisses develop from acidic igneous rocks, and mafic gneisses from basic igneous rocks. “Mafic and ultramafic gneisses are generally found together in this part of the Lewisian Complex, and are considered to be metamorphosed varieties of gabbro and peridotite” (Waters, 2003).
The Lewisian Complex has been subjected to successive developments in techniques of age determination. There has been progressive tightening of constraints from Rb-Sr (rubidium/ strontium), K-Ar mineral (potassium/ argon) mineral dating, Rb-Sr and Pb-Pb (lead) whole rock studies through U-Pb dating of bulk zircon fractions, Sm-Nd rock and mineral investigation, to the most ...Download file to see next pagesRead More
Cite this document
  • APA
  • MLA
  • CHICAGO
(“How old are the rocks of the Lewisian Complex in NW Scotland, and how Essay”, n.d.)
Retrieved from https://studentshare.org/miscellaneous/1569298-how-old-are-the-rocks-of-the-lewisian-complex-in-nw-scotland-and-how-do-we-know
(How Old Are the Rocks of the Lewisian Complex in NW Scotland, and How Essay)
https://studentshare.org/miscellaneous/1569298-how-old-are-the-rocks-of-the-lewisian-complex-in-nw-scotland-and-how-do-we-know.
“How Old Are the Rocks of the Lewisian Complex in NW Scotland, and How Essay”, n.d. https://studentshare.org/miscellaneous/1569298-how-old-are-the-rocks-of-the-lewisian-complex-in-nw-scotland-and-how-do-we-know.
  • Cited: 0 times
Comments (0)
Click to create a comment or rate a document
CHECK THESE SAMPLES - THEY ALSO FIT YOUR TOPIC
Epistemology: How do we know that we know something

The author states that philosophers have a hesitation about intuition as a justification for knowledge. Although in reality intuition is very common to all humans, it is undeniable to think that knowledge to be justified by mere immediate and personal certainty of a person could be based only to wild guesses and do not contain justifiable truth.

3 Pages(750 words)Essay
How do we know God exists
Initially, most people believe in what they are taught by their parents but these beliefs can gradually change with the passage of time due to change of mind or any other influence. In most cases this does not happen mainly because of fear.
2 Pages(500 words)Essay
How Are We Socialized
People differ in their level of exposure to the society. What fundamentally makes the difference is the confidence. Two boys who study in the same school and are class-mates vary in their number of friends. One has many friends while the other has none. Both boys come from the same family background and their economic status is also equal, yet their social skills vary so much that they look the opposite of each other.
7 Pages(1750 words)Essay
Know-How and Knowledge Intensive Organizations
This paper is going to delve into the similarities and differences of the ideas and principles that have been expressed by the author in both books with those of other authors. The Invisible Balance Sheet versus Human Capital and the Balance Sheet The ‘Invisible Balance Sheet’ quotes the organization as being largely dependent on the human capital which it describes as the professionals, the revenue people, the expert employees or the billable or chargeable employees.
4 Pages(1000 words)Essay
How We Got Lincoln
Seward. Manifold events happened in late 1859 and early 1860 that gave a boost to Lincoln’s chances in presidency. For example, the selection of Chicago as the location for the Republican convention, which was a decision put forward by the Illinois Republican chairman Norman B.
3 Pages(750 words)Essay
How Do We Know What We Think We Know
According to the report, today, the news is available everywhere, from serious news programs to satire comedy to internet web pages to Twitter text messages. What holds true for our general news also holds true for what we think of the scientific news. New approaches, policies, and inventions are quickly reported on and then we're off to a new topic.
7 Pages(1750 words)Essay
How should Scotland vote
In 1603, England and Scotland agreed to unify their crowns with King James VI of Scotland as the general monarch of the isle of British. In 1707, the
6 Pages(1500 words)Essay
How can we Know the Nature of Reality
In this aspect, the problem of reality and ways of its comprehension, in most cases finds its expression in the theory of knowledge. This topic has been well articulated by Socrates and his student Plato, who (especially Plato)
4 Pages(1000 words)Essay
How We Change
But, looking at the world of today, we see that we have progressed a lot in the past few centuries. We no longer need to write on the walls instead we have books and internet to keep record of history. We have made
2 Pages(500 words)Essay
How Do We Know What We Know Quiz
Tradition explains many their social tie, different clans and tribes within given societies. Expert authorities like government provide information on culture in statistical analysis. The information states have on their location, population and level of
2 Pages(500 words)Essay
Let us find you another Essay on topic How old are the rocks of the Lewisian Complex in NW Scotland, and how do we know for FREE!
Contact us:
+16312120006
Contact Us Now
FREE Mobile Apps:
  • About StudentShare
  • Testimonials
  • FAQ
  • Blog
  • Free Essays
  • New Essays
  • Essays
  • The Newest Essay Topics
  • Index samples by all dates
Join us:
Contact Us