Hydrogeological and Hydrochemical Parameters Proved Presence of Structural Closures and Destructions in the Hathout and Shar Areas in MZ-PZ, in the Southern Flank of Rub Al-Khali Basin. Yemen.

By: Dr. Abdul Sattar Othman Nani.

       Scientific Consultant to PEPA - Chairman.

        ( Phd Thesis- 1984 ).

ASNANI@y.net.ye

Introduction.

During the preparation of the PhD Thesis from 1982 till 1984 on the area in the Southern Flank of Rub Al Khali Basin and North Hadramaut Arch.

A new idea was introduced using Hydrogeological and Hydrochemical data to prove presence of structural closures in the Paleozoic Sedimentary Section.

Hydrogeological and Hydrochemical data of wells Hathout-2 and Shar-1, which were drilled by SPPE and also surface structural  geological survey, magnetic, gravity and seismic data were implemented.

Hydrogeological and Hydrochemical Parameters.

It is very

 important to note that, the chemical content of the water in the Cretaceous was Sodium Bicarbonate  (NaHCO3) and Sodium Sulphate ( NaSO4 ) proving water movement.

In Jurassic in the Hathout and Shar areas had Calcium Chloride ( CaCl2 ) water, which proves that, there was a structural closure.

In Triassic, Hathout area had ( NaHCO3) water, showing water movement, which in turn means open structure. But in the Shar area the water was CaCl2, showing structural closure ( Fig-1). This led to the Tectonic Oscillation, in the Southern Flank of the Rub Al- Khali Basin. This Phenomena was identified during the PhD Thesis . Eight Unconformities were observed.

In Paleozoic ( Early Devonian- Permian Age ) was for the first time introduced in the PhD thesis based on Micro-Paleontological analysis done in Agip laboratory in Milano and was introduced in the International Lexicon Of Strtigraphy- Volume III,(1998) on page 99  upon the recommendation of Late- Prof- Z.R.Beydoun.

The Paleozoic water in Hathout and Shar are of CaCl2 type. Proving closure of the structures ( No water movement ) in Paleozoic. This in turn proves that in Paleozoic the vertical Tectonic Oscillation were mild in nature.

Structural Analysis of Bahad Structure in the Hathout- Shar area done by us ( Dr. Nani and Eng. Mubarak Ba Mahmoud proved presence of Structural coincidence.(Fig-2,3).

Conclusion.

1- Hydrogeological and Hydrochemical parameters could be used as a tool in the Southern Flank of Rub Al- Khali for the detection of Structural Closures.

2- Structural Opening could be due to the co-sedimentation faults.

Recommendation.

1- It is very important that PEPA gets a complete set of water analysis( including Hydrochemical ) from the oil companies during the well testing at  the exploration phase in any of the Blocks.

References.

1- Dr.A.S.O.Nani, PhD Thesis. Geological Structure and Hydrocarbon Potentiality of Paleozoic and Mesozoic sediments in the Southern Flank of Rub Al-Khali Basin and North Hadramaut High. 1984.

   6/8/2006