1 90190 Level 1 Science, 2005 90190 Describe aspects of geology Credits: Five You should answer ALL the questions in this booklet. For Assessor’s use only Achievement Describe aspects of geology. Achievement Criteria Achievement with Excellence Achievement with Merit Explain aspects of geology. Discuss aspects of geology. Overall Level of Performance © New Zealand Qualifications Authority, 2005 All rights reserved. No part of this publication may be reproduced by any means without the prior permission of the New Zealand Qualifications Authority. You are advised to spend 30 minutes answering the questions in this booklet. QUESTION ONE The picture below shows a riverbank exposure of a layer of sandstone overlying a light-coloured mudstone. [FOR COPYRIGHT REASONS, THIS RESOURCE CANNOT BE REPRODUCED HERE. SEE BELOW.] http://www.uky.edu/OtherOrgs/KPS/pages/conferences/australasianhtml/newzealand/newzealand2.html (a) Major types of rock are classified as being igneous, metamorphic or sedimentary. What type of rock is sandstone? (b) Describe an important difference between mudstone and sandstone. (c) Discuss the processes that lead to the formation of sandstone. You should consider the rock cycle and geological processes. A labelled diagram may assist with your answer. Use this box for any diagrams. L1 Science 2005, 90190 – page 2 of 5 QUESTION TWO The picture below shows an example of the igneous rock obsidian. Obsidian is often called volcanic glass. [FOR COPYRIGHT REASONS, THIS RESOURCE CANNOT BE REPRODUCED HERE. SEE BELOW.] http://astron.berkeley.edu/~jrg/Polish/Obsidian-close-up.jpg (a) Explain how a glassy igneous rock like obsidian is made. (b) Igneous rocks are often classified as being plutonic or volcanic in origin. Name a rock type that is volcanic (other than obsidian) and a rock type that is plutonic. Volcanic: Plutonic: (c) Explain why plutonic rocks have much larger crystals than volcanic rocks. L1 Science 2005, 90190 – page 3 of 5 QUESTION THREE Metamorphic rocks are pre-existing rocks that have undergone change through time. (a) Name TWO physical factors that are involved in the formation of a metamorphic rock. 1. 2. (b) Name TWO metamorphic rocks other than schist. 1. 2. The ‘Otago schists’, as shown in the photograph below, make up a vast area of spectacular high country in the South Island of New Zealand. [FOR COPYRIGHT REASONS, THIS RESOURCE CANNOT BE REPRODUCED HERE. SEE BELOW.] http://www.cleangreen.co.nz/gallery1/central/4.htm (c) Name the type of metamorphism associated with the formation of schist. (d) Discuss how the metamorphic rock schist is formed. Use this box for any diagrams that may assist your answer. L1 Science 2005, 90190 – page 4 of 5 QUESTION FOUR The diagram below illustrates a type of unconformity. An unconformity is a gap or break in the rock record indicating changes in geological environments. The letters A – E indicate layers of sedimentary rock. (a) Discuss a sequence of geological events that might have produced the pattern of sedimentary rock strata as seen in the diagram above. (b) Explain how a geologist would determine that one rock layer is older or younger than another. (c) The picture below shows an igneous dike. A dike is a vertically intrusive igneous rock. [FOR COPYRIGHT REASONS, THIS RESOURCE CANNOT BE REPRODUCED HERE. SEE BELOW.] http://mason.gmu.edu/~sharlan/adelmountainvolcanics_files Explain why a geologist could be confident in stating that the igneous dike is younger than the surrounding rock. L1 Science 2005, 90190 – page 5 of 5