Expert: Farrukh Qayyum - 11/3/2009

Question
QUESTION: sir please if you can tell me about the origin and sedimentation on different basins of Pakistan?

ANSWER: Hello Ijaz,

Hope you are doing great. I am glad that you are heading towards buliding an understanding about the basin. A basin is originated due to thermal/tectonic/mechanical/chemical subsidence. The indus basin is also originated in a similar way but its origin dates back to Pre-cambrian history. That time connects the basin with other basins i.e. arabian/oman/persian basins. Therefore, you should read about the Paleozoic Plate Tectonics of the Arabian, Oman and Pakistan. That you can find in many text books. You can also Google them. I'll avoid writing about it because it costs too much time. There is a file uploaded to the following link. Go and download it.

http://depositfiles.com/files/d1fr3i045
or http://www.scribd.com/doc/21248882

The oldest known sedimentary rock in Pakistan is Salt Range Formation. Upto the Cambrian depositional cycle are partially complete. There is a complete hiatus or missing gap between the Cambrian-Permian. There is no sediment preserved in the Indus basin during this time. Possibly due to non-deposition or erosion. The Permian deposition is also complete and the sedimentation occured at the continent and continental slope margin. The Permian deposition is also a result of global glacio eustatic cycle that started with Tobra formation. The Meszoic sedimentation is comprised of several cycles (continental and shallow marine). The Cenozoic history in the upper edge of the basin is completely changed due to a collision with Eurasian plate. This transforms the basin in to a flexural basin over which thick Siwaliks are deposited. If you are interested to read in depth. I'll advise you to go through the text book. Specifically, the Petroleum Geology of Pakistan written by I. A. Kadri is a good start.

Good luck

Farrukh

---------- FOLLOW-UP ----------

QUESTION: sir i am so thankfull for your references.....i hav another question
location of permo traissic boundry in pak.
what happens along this boundry
what is cause of formation of this boundry
where else can it be found in the world??
sir i will be waiting for ur reply.....thnkyou so much..

Answer
Dear Ijaz,

I will be glad if you could find the answers to these questions in the same references that I mentioned earlier on (Book: Petroleum Geology of Pakistan). Permo-Triassic glacial and global sea-level changes have affected most of the continents. It exists throughtout the global basins record. Try to Google the word once, "Permo-Triassic boundary". You will find several studies done around the world.

If you have specific question, please do not hesitate to contact again. I appologies for a short answer because, the time that I will spend in typing, has already been spent by someone else. Try to find the answers in that big book.

Have a nice day.

Regards,

Farrukh