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Possible Of Hydrocarbon Origin In The North

 Hadramawt Is From Qamar-Jeza Basin.

( The new exploration phylosophy should discard the old

   understandings in order to achieve better results-Dr.Nani)   

Introduction:

North Hadramawt High(Fig-1) is a Paleo-High is geologically situated between Qamar-Jiza Basin from the south and to the north by Southern Klank of Rub Al-Khali Basin. To the east it continues into Sultanate of Oman, where it is called Ghudun-Khasfah High.To the west it merges into Marib-Jawf High

Exploration activities started in the early 60's by PAHOC and PAMOC and later on in 70's by SYAPCO and later on by Thamud Project (Cubians). In 80's by SPPE ( Russians ) and in 90's by Nimir.

Exploration results proved presence of shallow sedimentary cover with good Reservoirs, Seals and Traps but immature Source Rocks. Presence of hydrocarbons in the wells Tarfayt-1, CH-85 and 88, Taur-1 and Thamud-1. These hydrocarbons had most probably generated from the Qamar-Jiza Basin(Fig-3), where deep seated faults(fig-2) played the role of hydrocarbon carriers.

Qamar-Jiza is a

 Cretaceous Basin( Fig-1). Exploration activities were carried out by Agip, Braspetro, Nimir proved that, the thickness of the Cretaceous reaches more than 1500m. These sediments have excellent Reservoirs, Source Rocks, Seals and Traps. About the Jurassic sediments up to now it is a very big Puzzle! If it is present in the basin then will open a new Scenario for the future hydrocarbon exploration in the Qamar-Jiza Basin.

It is for sure that Naifa Fm if present will be mature and will play an important role for hydrocarbon generation along with Harshiyat Fm , Saar Fm and Madbi Fm.

North Hadramaut High:

The thickness of the sedimentary cover reaches up to 1850m in the well Thamud-1. The following Fomations are present:

-Habshiya

-Jeza

-Umm er Radhuma

-Sharwayn

-Mukalla

-Maqrat mem

-Tuhayr mem

-Duha Suhis mem

-Hashiyat.

-Qishn Cabonate( Reef )

-Granitic washed and Fractured Basement.

*In the well Thamud-1, Paleozoic? sediments lie over the Metamorphic Basement.

TectonicallyNorth Hadramawt High is a Paleo-High, its culmination took place in the Upper Eocene (Fig-4,5).

Qamar-Jiza Basin. Is a Cretaceous Basin. The thickness of the Cretaceous  sediments increases towards the east. Wells which had been drilled in the basin are:-

1- Gamma-1. T.D. 2905m. Nimir.

2- Al-Furt-1. T.D. 4400m. Braspetro.

3- Arma-1. T.D. 2892m. Braspetro.

4- Wadi Jeza-1. T.D. 2850m. Braspetro.

5- 16/U-1. T.D. 3300m. Nimir.

6-  Al-Fatk- IX. T.D. 4300m.  Offshore. Agip

7- Al-Faydami-IX. T.D. 1656m. Agip.

All these well show presence of big thickness of the Cretaceous sediments reaching more than 3000m and still in the Harshiyat Fm.

Jurassic sediments which were penetrated by wells Al-Furt-1 and Arma-1 are as follow:

1. Pre-Qishn-A ( Possible Saar- Naifa Equivalent ).

2. Pre-Qishn-B ( Possible Madbi Equivalent )

3- Shuqra Fm. Presence of Foraminifera Kurnubia palasteinensis indicating Callovian- Oxfordian age.

4- Kuhlan Fm.

It is very important to note that, presence of Bitumenous shales in the Pre-Qishn-B in the well Al-Furt-1, that source rocks are present. Deep faults could play a very good role as carriers of hydrocarbons from the basin to the North Hadramawt High.

Conclusion.

1- The Oil and Bitumen in the North Hadramawt

     High is possible from the Qamar-Jiza Basin . This

     is due to absence of matured Source Rocks in the 

     North Hadramawt High.

2- The deep seated faults played the role of carriers

     for the hydrocarbons.

3- Presence of Qishn Reefs on the Granitic Basement

   is an excellent trap, since Reefs have primary

   porosity.

Recommendation.

1-Future explorations wells should  drill deeper in the Qamar-Jiza Basin, so that to penetrate Jurassic sediments for the purpose of Geochemical investigations.

2- Weathered and Fractured Granitic Basement in

     the Hadramawt High,should be studied thoroughly

     during the future exploration activity. 

References.

1- PhD thesis.

    Geological structure and hydrocarbon potentiality

     Paleozoic and Mesozoic sediments in the Southern

     Flank of Rub Al-Khali Basin and North

     Hadramawt High. 1984.

2-  Geological Evaluation of Qamar-Jeza Basin. Eng.

      Amin Noman Al-Maktari – 2000.

3-  International Lexicon 0f Stratigraphy. Volume III.

     Republic of Yemen. Z.R.Beudoun, Mustafa A.L.

     As.Saruri, Hamed El-Nakhal, Ismail N.Al-Ganad,

     Rasheed S. Baraba, Abdul Sattar O.Nani and

     Mohamed H. Al-Aawah. 1998.