# HYDROSPHERE – OS MAPWORK

## Presentation on theme: "HYDROSPHERE – OS MAPWORK"— Presentation transcript:

HYDROSPHERE – OS MAPWORK
Using an OS map, you should be able to describe the main characteristics of a river and its valley This question is not unlike the one you faced at S.G. You will be asked to describe the Physical features of a river and perhaps its valley – do not mention bridges, settlement etc. Remember to give grid references – marks are given for this!

HYDROSPHERE – OS MAPWORK
Weak Answers: The river starts off straight, flowing N and then swings to the W, before going NE and then NW, NE again and then NW, N, NW and back NE and N. The river has a lot of meanders. It flows under a bridge at and goes through woodland at What do you think of this answer? 1. First sentence = 1 mark. General comment on direction is enough 2. Gets two marks but could have got two for simply saying: ‘The river meanders to the NW’ 3. Woodland and bridge references are irrelevant 4. No grid reference given for meanders 5. No mention of valley 6. No mention of any other features

HYDROSPHERE – OS MAPWORK
Strong answer: The river meanders to the NW. An example of a meander is found at The river is roughly the same width throughout the section and could be in its middle course. There are 2 tributaries with confluence points at and There is an ox-bow lake at There is an embankment at suggesting that the river is prone to flooding here. The valley has a flood plain which widens from 500m wide in the South to 2km wide in the North. The East side of the valley is gently sloping to over 30m whereas the West side is steep, rising to over 70m. What do you think of this answer? Can you draft up a list of questions you should be aiming to answer?

HYDROSPHERE – OS MAPWORK
Can you draft up a list of questions you should be aiming to answer? Physical Features of River: What course is the river in? STRAIGHT OR MEANDERING? DOES IT GET WIDER AS IT FLOWS DOWNSTREAM? DIRECTION OF FLOW? SPEED? GENTLE OR STEEP SLOPE? Features to note if present (give grid references) Braiding, embankments, oxbow lake, meanders, waterfalls Tributaries How many? From which direction do they come?

HYDROSPHERE – OS MAPWORK
Physical Features of Valley: Trend – E.g. North to South, East to West etc. Shape – U-shaped or V-shaped, gorge, steepness of valley sides Width – How wide is the valley floor? Can you measure? Features – flood plain, interlocking spurs Height – valley floor and valley sides E.g. valley floor descends from 300m to 290m valley sides rise from 100m to over 400m

HYDROSPHERE – OS MAPWORK
PAST PAPER QUESTION 2005 Using appropriate grid references, describe the physical characteristics of the River Bleng and its valley from (Stockdale Head) to (where it meets the River Irt). 8 MARKS Complete in groups Take 10 minutes to get down as much information as possible Swap with another group – add to their answer (3mins) Swap again, look at the marking scheme grade the answer in front of you