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so this is my first time here because I need help in identifying the features on this rock formation. https://www.flickr.com/gp/158064920@N05/6USrY9

Thank you in advance.

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    $\begingroup$ what are your question? is it the location or the composition or maybe the geological history.each set of alternatives needs different details added to your question,please read this earthscience.meta.stackexchange.com/questions/124/… and update your question with all the details you can. $\endgroup$ – trond hansen Dec 7 '18 at 9:02
  • $\begingroup$ Hello, my questions are: for the image titled earth 11 what is the name of the feature that is creating the long vertical lines. for some reason I am going with jointing? I may be wrong. For the image titled earth 13, I want to know whether there is faulting, erosion, or conformable contact occurring at the red circled area. This rock is 3/4 sandstone until the far right where there is rounded gravel (conglomerate?) and i want to know what is making that happen. The images titled earth 5 and 6 are the gravel (conglomerate?) Thank you once again $\endgroup$ – Sara Dec 7 '18 at 9:26
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in picture 11 there is erosion by water and wind.

it is sandstone and this is easily eroded by water each time it rains the water takes particles of the sandstone and moves them down the mountain.

sorry for this short and bad answer,it was a simple question so the answer is simple too.

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The rounded gravel was part of a river channel cutting through the sandstone. No faults. You can Google the term channel facies.

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The long vertical lines on "Earth 11" are not joints, but are rills. As water flows across the surface and becomes turbulent, it picks up the unprotected sediment and carries it off.

There is no reason to believe that "Earth 13" is a fault, unless you found slickenlines or other fault features. The overlying rock is indeed a conglomerate (specifically an orthoconglomerate), and the rock below appears to be a sandstone. It's hard to say if the contact is conformable or not, but the gap between the two rocks probably doesn't represent a huge amount of time.

Such deposits are similar in fluvial settings. Basically, as a river meanders back and forth, the stream capacity is always in flux. That means there are times when the river is eroding, and there are times when the river is depositing sediment. The sandstone was probably deposited on a point bar in slower moving water than the conglomerate, which was deposited by faster moving water.

In summary: this formation is probably the result of a paleoriver. Rounded conglomerates, such as the one in the image, are typical of fluvial deposits. (Angular conglomerates usually have different depositional settings). Alternating packages of siltstone, sandstone, and conglomerate are also typical of fluvial deposits

PS - I'm a licensed geologist, so I like to think I know what I'm talking about.

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