iGeo 2012, Писмен тест — Задача 21. Section E: Rivers
Written Response Test — Question and Answer Booklet — 9th International Geography Olympiad — Cologne, Germany — 21–27 August 2012 · 21 август 2012 г. · 4 т.
Внимание: Бележка към темата
The Source Booklet (Sources A1–F1) referred to in the questions is not part of this paper's files; only the copies of Source B1 Maps A and B and Sources E1 and E3 printed in the answer booklet are reproduced.
Instructions for the students
- This test consists of 6 sections.
- The maximum total mark is 90. The mark for each question is given at the beginning of the question.
There are a maximum of 15 marks for each section. - Give only the required number of answers (reasons, examples, et cetera). For instance, if the question asks for 2 reasons and you give more than 2, only the first 2 reasons will be marked.
- Answer all questions in the spaces provided in this booklet.
- Check the backs of pages as questions are printed on both sides of a page.
- Fill in your name, team and student number on the front page of this booklet.
- Fill in your iGeo student number in the boxes on top of the pages in this booklet.
- The Source Booklet contains the maps and figures referred to in the questions.
- Time: 180 minutes for non-native English speakers; 150 minutes for native English speakers.
- Non-native English speakers may use bilingual dictionaries during the test.
- You may use a calculator during the test.
- You may use the atlas provided during the test.
Good luck!
Marking scheme - overview
| section A | section B | section C | section D | section E | section F |
|---|---|---|---|---|---|
| 1 - 2m | 1 - 1m | 1 - 3m | 1 - 3m | 1 - 4m | 1 - 4m |
| 2 - 1m | 2 - 1m | 2 - 3m | 2 - 8m | 2 - 1m | 2 - 2m |
| 3 - 4m | 3 - 1m | 3 - 3m | 3 - 4m | 3 - 3m | 3 - 3m |
| 4 - 1m | 4 - 9m | 4 - 2m | 4 - 1m | 4 - 6m | |
| 5 - 1m | 5 - 3m | 5 - 4m | 5 - 1m | ||
| 6 - 2m | 6 - 3m | ||||
| 7 - 4m | 7 - 2 m | ||||
| 15 marks | 15 marks | 15 marks | 15 marks | 15 marks | 15 marks |
Условие
Outline the 4 different ways in which a river transports particles of different sizes in its channel.
Решение
4 marks
- Traction (1/2) where large bedload - boulders, cobbles, larger pebbles (1/2) - is rolled along the bottom (1/2). Only really occurs at high discharge (1/2). Distance travelled is relatively short (1/2)
- Saltation (1/2) where smaller items of bedload - smaller pebbles, gravel, sand -(1/2) bounce/hop along the river bed (1/2); local changes in flow lead to it being dropped and then picked up again (1/2).
- Suspension (1/2) where finer sand, silt, clay (1/2) is carried within the water itself (1/2).
- Solution (1/2) where certain rock types, e.g. chalk, limestone (1/2) are dissolved (1/2) in the slightly acidic river water (1/2).
Note
Students need to identify 4 processes (by getting at least ½ mark for each process), to get full marks. They can add other marks (up to a maximum of 4 for the total) by getting extra marks for details of some processes, up too maximum 2 marks for any one process.
Students who only identify 3 processes can only get max 3 marks; students who only identify 2 processes can only get max 2 marks; students who only identify 1 process can get only max 1 mark.
Оригинал в Архива: 2012WRTQandA.pdf · официални решения: 2012WRTmarkingscheme.pdf