Help Drawing a Quaternary Deposits' Profile in Uppland, Sweden

[Lotta]

<mentor: moved to homework forums - no template okay in this case>

Please I need help with this one!

Drawing a Quaternary deposits’ profile
The purpose with this practical is to understand how a map showing Quaternary accumulations is built up and how it may be interpreted. The information is shown in 2- dimension but has to be interpreted in 3-dimensions, i.e. stratigraphy. The task is to draw a section based on information along the profile from A to B in the lowermost figure. As a guide there is a general section shown and a legend. Draw the different Quaternary deposits in the right order and the right extension along the profile. You have to exaggerate the elevation scale in order to fit in all accumulations. A good starting point is to draw the bedrock topography first and then fill in the various accumulations in chronological order. Note that altitude-lines for the surface topography are indicated in the map. Also write maximum 600 words describing the various landscape changes over time that caused these accumulations. The profile is located in Uppland, eastern central Sweden.
Note that the transect in figure 3 is an example of a typical transect, and NOT the correct answer!

I have attempted to draw a straight line from point A to point B but that is wrong :/ How am I supposed to draw this?

 

[haruspex]

I would start by using the altitude information to draw a profile of the surface along the line AB.
If you can figure out which colour marks the most recent deposit, you can then add those sections as lenses hanging under the profile line. Then go for the next most recent deposit. Where two instances of that flank only more recent deposits, continue the stratum under the more recent ones to join up the instances.
What I cannot see how to do is to decide where you should not connect up instances like that. E.g. in the example it shows the big green blob sitting directly on the red band; the light blue band, with an age between those of the green and red, only continues a short way under the green. There is no way to tell that from the surface data.

 

[Lotta]

Thank you so much! But I don’t know how to draw it at all, how do I know what shape it should be? And how long?

 

[haruspex]

Thank you so much! But I don’t know how to draw it at all, how do I know what shape it should be? And how long?

The first part, the surface profile, is like drawing a graph. Going from A to B is along the x axis, while the heights given by the contour lines in the first figure give you the y axis.

 

[Lotta]

But how do I know the lengths? And which direction?

 

[haruspex]

But how do I know the lengths? And which direction?

The figures as posted are not very clear, so I cannot be sure whether there are any contour heights or spot heights on the map. But you do not need any. Just assume the contour lines are at equal height intervals. Where you see a closed loop contour you can assume the uphill side is inside the loop - unless there is a lake inside it.
Mark equal distances up the y-axis to correspond to the contour lines. See where they cross the AB line and mark the corresponding (x,y) points on the graph.

If you still do not understand you will need to post much clearer images so that I can be more specific.

 

[Lotta]

Here are the pictures, please help me! :(

 

[Lotta]

https://i.postimg.cc/fL4PbrmC/572668-D6-F572-4-CA5-9-DEB-DE52-B1360889.jpg
https://i.postimg.cc/85h0fmbS/D556-D111-C18-D-4-BD5-B785-E714-E7736-AA9.jpg
https://i.postimg.cc/5tQGbVYj/DD46-E7-B9-DB69-4467-93-EA-50-A6-D12-D5081.jpg

 

[Lotta]

Maybe that is easier to see

 

[Lotta]

I also have this that was posted before! If it even help :(

Below is a general stratigraphy in an overgrown and ombrotrophic mire below the highest coast line in middle Sweden shown. This scheme includes both inorganic and organic types of accumulations indicating a gradual decrease in energy.

The lowermost till was accumulated when ice covered the area. The superimposed glacial clay was accumulated in deep water containing particles from the meltwater streams. South of the Middle Swedish End Moraine Zone this could have taken place in the Baltic Ice Lake. North of the same zone, accumulation took place in the Yoldia Sea. This unit is sometimes clearly varved, representing seasonal variations in the meltwater streams. In Yoldia Sea, however, varves might not be so clear because of interactions between clay particles and ions in the water. These forms aggregates causing fast accumulation, thus "hiding" seasonal variations. The lowermost parts are often sandy becasue of proximity to the glacier meltwater mouths. In eastern Svealand this clay often contains Ordovician limestone transported from the bay "Gävlebukten" further north.

The postglacial clay is a mixture of reworked glacial clay and newly introduced particles from nearby land areas and river mouths. The color is often bluish, sometimes with black sulfide precipitations. This unit mostly reflects conditions in the Ancylus Lake and has a flat upper surface (because of a shallower water depth when accumulated).

Gyttja clay holds a higher organic content representing a warmer climate. This unit represent accumulation in the Litorina Sea, i.e. after flooding of the Danish Straits and Öresund. Clay gyttja is dominated by organic material and accumulated in relatively sheltered bays in an archipelago. These types of material is accumulated in the large lakes Mälaren, Vänern, Vättern and Hjälmaren.

In small lakes gyttja may be produced. In general, the transition from clay gyttja to gyttja repesent the isolation of the basin, i.e. the formation of a small freshwater lake. If the lake is small and shallow enough reed belts can cover the surface completely forming reed peat (Phragmites peat).

As peat starts to form there will be a decrease in pH and nutrient availability. If there is a lack of carbonates Carex will invade allowing fen peat to accumulate. When these processes continue even further different species of Sphagnum will be establish lifting the ground surface even more; moss peat is accumulated. In high nutrient areas carr peat may be formed.

Sphagnum peat has been used to reconstruct climate change. Since these peat areas develop separate ground water surfaces, low precipitation will cause more efficient decomposition and form recurrence surfaces. Caution has to be taken, however, to local variations.

 

[DaveC426913]

Lotta: we cannot do your homework for you. It is forbidden by the forum rules.
You must show your attempts at it, and ask specific questions, and we can address those.

 

[jim mcnamara]

Moved to homework forums. No homework template, which is okay in this case.

 

[haruspex]

Maybe that is easier to see

Yes, that's better.
I'll try to talk you through an example.
Find the 't' of Nybygget. Go north to the line AB. This is in an orange area. Just to the east and west a loop of contour line crosses AB. The loop is mostly to the northeast. A bit further east a smaller loop also straddles AB.
You can interpret each of these contour lines as surrounding a hill. Since there are no other contour lines separating them, the two contours are at the same height, and the region between them is a dip.
Pick a y value to represent the height of this contour line and mark the four crossing points on your chart. The x coordinates are the distances from A. Sketch in the two hills and the dip. These will only be small since they do not reach the next contour heights.

 

[DaveC426913]

Pick a y value to represent the height of this contour line and mark the four crossing points on your chart. The x coordinates are the distances from A. Sketch in the two hills and the dip. These will only be small since they do not reach the next contour heights.

I get
A at 50+
a plain between 40 and 45
with two hills above 45
a valley that dips below 30
a tiny hill that just goes above 35
a long slope up to 35 at B.
That seem right?

 

[haruspex]

I get
A at 50+
a plain between 40 and 45
with two hills above 45
a valley that dips below 30
a tiny hill that just goes above 35
a long slope up to 35 at B.
That seem right?
View attachment 238917

It's hard to figure out whether the first section from A is tending uphill or downhill. Looks to me like uphill.
I cheated and found
https://www.google.com/maps/dir/Eri...a43aa5e8f5c!2m2!1d17.9194346!2d59.6254993!3e2
Nybygget is shown at about 35m.
Note that "up" on the supplied map is roughly SW.

 

[Lotta]

Thanks for answering! Is that the curve for my assignment? How do I know where to color it?

 

[DaveC426913]

Thanks for answering! Is that the curve for my assignment?

No. That's my take on it. You need to work it out for yourself.

How do I know where to color it?

Read the description, study the legend and refer to your lesson notes.

 

[DaveC426913]

I cheated and found

I had tried too, but couldn't find the other towns. :)

 

[Lotta]

But just so I know- is the curve supposed to look like that?

 

[DaveC426913]

But just so I know- is the curve supposed to look like that?

I don't know. I haven't studied Geography since high school, and I don't have course marks relying on my being right.

My advice is that, having been given a helping hand, and a basic idea where you can expect to end up, you make the attempt yourself.

Why don't you give it a try and it you run into trouble, ask us questions.

 

[DaveC426913]

I had tried too, but couldn't find the other towns in Google. :)

Man, I can't find any correlation between the geography an Google map not even the roads ...

 

[Lotta]

I will try! In just in a hurry :(

 

[haruspex]

It's hard to figure out whether the first section from A is tending uphill or downhill. Looks to me like uphill.
I cheated and found
https://www.google.com/maps/dir/Eri...a43aa5e8f5c!2m2!1d17.9194346!2d59.6254993!3e2
Nybygget is shown at about 35m.
Note that "up" on the supplied map is roughly SW.

Forget all that... despite the myriad of Nybyggets in Uppland I happened to pick the right one, but the Eriksberg and Stenhagen were spurious.
Finally found it south of Stockholm Arlanda airport.

Lotta, if you bring this up in Mapcarta (https://mapcarta.com/17680158/Directions; you may need to go left and down a bit) and zoom in more than in the above image it will give you 10m contour lines.

 

[Lotta]

I can’t see Any? I am sorry I’m really bad at this! Its a onlinevourse I’m taking that I just need to pass to keep my spot at another program :(

 

[haruspex]

I can’t see Any? I am sorry I’m really bad at this! Its a onlinevourse I’m taking that I just need to pass to keep my spot at another program :(

Can't see any what? Contour lines?
Starting with the screen that comes up at the link I posted, make the map area full screen, then scroll left and down until you see the Arlanda golf course at bottom left and the southernmost bit of the grey airport area at top right. You will see the E4 as a vertical line.
Zoom in once or twice and you should see contour loops labelled as 50m, with some fainter contour lines. The fainter ones will be at 10m intervals, so those nearest the 50m lines will be either 40m or 60m.

 

[DaveC426913]

Zoom in once or twice and you should see contour loops labelled as 50m, with some fainter contour lines. The fainter ones will be at 10m intervals, so those nearest the 50m lines will be either 40m or 60m.

And then there's the issue of whether the 50m lines surround depressions or hills.
And had to scroll several miles to find a body of water to figure out which it was.

 

[haruspex]

And then there's the issue of whether the 50m lines surround depressions or hills.
And had to scroll several miles to find a body of water to figure out which it was.

Loops with no evidence of water inside are nearly always hills.

 

[DaveC426913]

Loops with no evidence of water inside are nearly always hills.

Probably, but I don't think it's a good assumption here, with such flat land. There are definitely depressions all around the area.

 

[haruspex]

I located it in Google Earth Pro and obtained this profile. The end points might not be exactly right, but I think I have it pretty much as an EW line of just over 3km. I suspect it is supposed to be exactly 3km.

 

[Lotta]

I can’t see Any? I am sorry I’m really bad at this! Its a onlinevourse I’m taking that I just need to pass to keep my spot at another

 

[haruspex]

I can’t see Any? I am sorry I’m really bad at this! Its a onlinevourse I’m taking that I just need to pass to keep my spot at another

You can't see the image in post #29?

This is strange... your post is identical to post #24 of nearly a week ago, down to the typos.

 

[Lotta]

That is so strange, I did not write that now haha? What I wanted to say is that I still don’t know how to draw the curve according to the task

 

[haruspex]

That is so strange, I did not write that now haha? What I wanted to say is that I still don’t know how to draw the curve according to the task

Draw an xy grid just like the one in the graph in post #29.
Measure along the AB line in the map you were given to the places where it crosses the contour lines.
Find the corresponding points along the x-axis in your graph, and along the AB line in the graph
In post #29. You should find that the heights in post #29 are close to multiples of 5m. If so, mark at that height on the graph you are making. Where possible, check that the height matches that in the map you were given.

 

[Mark44]

Thread closed. The OP has been given a lot of good suggestions, but has failed to act on them.