GeoLogic Mapping C

[Magikarpmaster629]

How are mid-ocean ridges formed?

[boomvroomshroom]

Answer: (Click to Show Hidden Text)

Just like most major mountain ranges, it's when two plates converge and push each other up (although in this case, they're converging underneath the ocean instead of on land).

[elephantower]

I'm not magi, but that's not correct. (Click to Show Hidden Text)

Reverse underwater faulting produces trenches; mid-ocean ridges are formed by normal faulting (specifically from magma welling up from the rift created).

It's the difference between pushing two bread loaves together (continental plates are thick but not dense, ) and pushing two greasy pancakes together (ocean crust is thin and compact).

[boomvroomshroom]

I'm not magi, but that's not correct. (Click to Show Hidden Text)

Reverse underwater faulting produces trenches; mid-ocean ridges are formed by normal faulting (specifically from magma welling up from the rift created).

It's the difference between pushing two bread loaves together (continental plates are thick but not dense, ) and pushing two greasy pancakes together (ocean crust is thin and compact).

looked it up, and you're right. Got confused; sorry! Thanks for the info

[Magikarpmaster629]

Yes, Elephantower is correct. Either of you may ask a question now!

[elephantower]

Yay.

Question/Problem:
Derive the analytical 3 point problem formula

true dip = arctan(tan(A1)/sin(90 - arctan(csc(θ)*(cot(A1)*tan(A2)-cos(θ)))))

Where A1 and A2 are the two apparent dips (A1 < A2) and θ is the angle between the A1 and A2 trendlines.
It looks stupidly complicated but it's actually extremely useful: much easier and more precise than constructing the solution. Also, I may have made a typo in it, please correct me if so.
Bonus points if you can simplify the final result.

[boomvroomshroom]

What do you mean by derive? I just drew a picture and labeled the sides, and did some trig.
Seems useful, but all the tests I've seen force you to show your work by drawing the picture thing, so...

[elephantower]

What do you mean by derive? I just drew a picture and labeled the sides, and did some trig.
Seems useful, but all the tests I've seen force you to show your work by drawing the picture thing, so...

Derive the equation from basic trig identities? Scan up/transcribe your work perhaps? I'm curious to see how you did it. I've never seen a test like that, but it's still useful to check your work, as it's easy to introduce error when constructing the answer.

[boomvroomshroom]

What do you mean by derive? I just drew a picture and labeled the sides, and did some trig.
Seems useful, but all the tests I've seen force you to show your work by drawing the picture thing, so...

Derive the equation from basic trig identities? Scan up/transcribe your work perhaps? I'm curious to see how you did it. I've never seen a test like that, but it's still useful to check your work, as it's easy to introduce error when constructing the answer.

*kind of lazy* but I just drew the regular 3-point problem diagram, sketched it out in 3D, labeled the sides, and did some algebra. I did it before (also had to derive the true dip/apparent dip thing this way) on some practice test. I just can't find it right now, so I don't know what I did exactly, haha. I might send it back to you when I have some time. For something as 'complicated' as a 3-point problem (I say 'complicated' as in compared to true thickness) I'd just memorize your equation. I've never seen a question that asked you to derive something.

Anyway, the tests I had said in the instructions "show your work on the graph below" and they gave you this thing to plot the 3 points on and whatnot.

[elephantower]

What do you mean by derive? I just drew a picture and labeled the sides, and did some trig.
Seems useful, but all the tests I've seen force you to show your work by drawing the picture thing, so...

Derive the equation from basic trig identities? Scan up/transcribe your work perhaps? I'm curious to see how you did it. I've never seen a test like that, but it's still useful to check your work, as it's easy to introduce error when constructing the answer.

*kind of lazy* but I just drew the regular 3-point problem diagram, sketched it out in 3D, labeled the sides, and did some algebra. I did it before (also had to derive the true dip/apparent dip thing this way) on some practice test. I just can't find it right now, so I don't know what I did exactly, haha. I might send it back to you when I have some time. For something as 'complicated' as a 3-point problem (I say 'complicated' as in compared to true thickness) I'd just memorize your equation. I've never seen a question that asked you to derive something.

Anyway, the tests I had said in the instructions "show your work on the graph below" and they gave you this thing to plot the 3 points on and whatnot.

Sounds good. Ask a question? Or I can give you a make-up question since that one was sorta silly