Roxana wrote:

>Oh my God! Those are cracks, not rivers!

Quite true. They are typical conjugate joints in bedrock that has been
stressed to the point of failure and fracturing. Originally, the joints might have
been filled as they formed with calcite. Once the block was exposed by erosion,
weathering subsequently dissolved the calcite leaving the cracks behind.

Pictures are at:

Shafiei, A. and Dusseault, M.B., 2012, June. Inferring In Situ Stresses in a
Naturally Fractured Heavy Oil Field. In 46th US Rock Mechanics/Geomechanics
Symposium. OnePetro. [www.researchgate.net] and PDF file at [www.researchgate.net]

Veins in conjugate joints - [myweb.facstaff.wwu.edu]

A technical discussion of how they form is:

Leng, X., Wang, C., Sheng, Q., Chen, J. and Li, H., 2021. An Enhanced
Ubiquitous-Joint Model for a Rock Mass With Conjugate Joints and Its
Application on Excavation Simulation of Large Underground Caverns.
Frontiers in Earth Science. 15, September 2021[doi.org]
[www.frontiersin.org]

Yours,

Paul H.

"The past is never dead. It's not even past."
William Faulkner, Act 1, Scene III, Requiem for a Nun (1951)



Edited 8 time(s). Last edit at 11/06/2021 03:47PM by Paul H..