The Tarim Basin - Laurie Bougeois

II- Formation of Tarim Basin. 1. A context of collision. 2. A sedimentary basin. 3. Retreat of .... landscape evolution along the Keriya River, Xinjiang, China: the.
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Earth History

The Tarim Basin formation of an endorheic basin and its climatic consequences Laurie Bougeois M1 PSP

 

 

Introduction General geology : a context of collision between the Indian Plate and the Eurasian Plate

    Tarim  Basin

Mettre une photo montrant  rapidement la collision et situant  le bassin du tarim. Cf livre le choc des continents

 

 

Outline I- The elements of Tarim Basin 1.

The Taklamakan : an endorheic desert

2. The boundary mountains 3.

Main rivers and lakes

II- Formation of Tarim Basin 1.

A context of collision

2. A sedimentary basin 3. Retreat of Paratethys Sea 4. Desertification and aridification III- Tarim Basin and origins of transition of paleoenvironnemental patterns 1.  

Uplift of Tibetan Plateau

2. Retreat of Paratethys Sea  

3. Which phenomenon is the main responsible?

I- The elements of Tarim Basin 1. The Taklamakan : an endorheic desert  Surname : « The desert of Death »

 Climate : very arid and big range of temperature : -40°C < T < +50°C  Area : 337 000 km² => 3rd bigger desert in the world

 Dunes of sand : up to 40m of hight (end of formation : 70ka ago)

 Formation of desert : Miocene with the retreat of an epicontinental sea (Paratethys)

 

 

I- The elements of Tarim Basin 2. The surrounding mountains

Tian Shan : northern border 

Composition : mainly crystalline

and sedimentary rocks of the

Paleozoic Era (540 - 250 Ma) 

n Sha lun  n u K



Orogenesis during Late Eocene

Highest peak : Victoria Peak

(7439 m)

 

 

I- The elements of Tarim Basin 2. The surrounding mountains

Kunlun Shan : southern border 

Principal folded structures and

granitic rocks date to 250 Ma 

Sedimentary cover : until

Jurassic

n Sha lun  n u K

 

Orogenesis 26 Ma ago

Highest peak : Kunlun Goddess

(7167 m)

 

 

I- The elements of Tarim Basin 2. The surrounding mountains

Pamirs : western border 

Formed by junction of the Tian

Shan, Karakoram mountains, Kunlun Shan and Hindu Kush ranges 

(7495 m)

n Sha lun  n u K

 

Highest peak : Ismoil Somoni

 

I- The elements of Tarim Basin 3. Main rivers and lakes a. Hydrological settings :  An endorheic basin

 Lots of rivers but only one go through the desert of Taklamakan

 

 

I- The elements of Tarim Basin 3. Main rivers and lakes b. Keriya River :

Takes its origin in the Kunlun Shan and finishes with a delta in the sand

 

Keriya river

 

I- The elements of Tarim Basin 3. Main rivers and lakes b. Keriya River :

Takes its origin in the Kunlun Shan and finishs with a delta in the sand

c. Khotan River :

Go through the Taklamakan (from South to North)

 

 

Khotan and Keriya rivers

I- The elements of Tarim Basin 3. Main rivers and lakes d. Tarim River :

 Go along the North of Taklamakan  Confluence = union of Asku, Khotan and Yarkand

 Longest river in the basin : {Yarkand+Tarim} = 2030 km

 

 

I- The elements of Tarim Basin 3. Main rivers and lakes e. Lop Nor :

 End of Tarim River

 Group of small salt lakes and marshes in a depression

 Area = 10 000 km² but decreases for several centuries

 

 

II- Formation of Tarim Basin 1. A context of collision  Remains of a microcontinent :

Turan

 Collision between the Turan Plate and the Eurasian Plate during Carboniferous and Permian

 

 

II- Formation of Tarim Basin 1. A context of collision  Remains of a microcontinent :

Turan

 Collision between the Turan Plate and the Eurasia Plate during Carboniferous and Permian

 

 

II- Formation of Tarim Basin 1. A context of collision  Remains of a microcontinent :

Turan

 Collision between the Turan Plate and the Eurasia Plate during Carboniferous and Permian

 

 

II- Formation of Tarim Basin 1. A context of collision



Since

between Plate 

Lots

Paleogene

Indian Plate

of

:

and

deformations

borders of the basin

collision

Eurasian

in

the

=> consequences of the thrust of Tian Shan and Kunlun Shan over the basin

 

 

II- Formation of Tarim Basin 2. A sedimentary basin  Sedimentation in the basin of Paratethys Sea (extended across the Eurasian continent during the Eocene)

 

 

II- Formation of Tarim Basin 2. A sedimentary basin  Paleogene Sediments - Permian mudstones – Precambrian shield  Accumulation of the most of sediments on the southeastern border (basin in slope)

 Big reservoir of oil and natural gases but which has lost its waterproofness because of tectonic movements

 

 

II- Formation of Tarim Basin 3. Retreat of Paratethys Sea  Retreat of Parathetys 30 Ma ago

 

 

II- Formation of Tarim Basin 3. Retreat of Paratethys Sea  Remains of Parathetys =

Caspiane Sea and Aral Sea

 

 

II- Formation of Tarim Basin 4. Desertification and aridification  Since the retreat of Parathetys : desertification and aridification during Late Miocene

 Formation of big dunes of sand  Lots of evaporation

 Today drought still increases and basin totally surrounded, closed

 

 

III- Tarim Basin and origins of transition of paleoenvironnemental patterns Two hypothesis for aridification in North and season of monsoon in South and the Eocene-Oligocene transition (34 Ma)

1. Uplift of Tibetan Plateau  Changes in the atmospheric circulation ➔ ➔

aridification to the North (Tarim basin) monsoon to the South

 Uplift and orogenesis = erosion ➔

consumption of CO2 and climate changes

 Positive feedback between uplift and erosion

 

 

III- Tarim Basin and origins of transition of paleoenvironnemental patterns Two hypothesis for aridification in North and season of monsoon in South and the Eocene-Oligocene transition (34 Ma)

2. Retreat of Parathetys sea  Before the retreat : ➔ ➔

stopped warming of Central Asia

decreased the development of monsoon in the South

 After the retreat : ➔

 

great aridification of Tarim basin

 

III- Tarim Basin and origins of transition of paleoenvironnemental patterns Two hypothesis for aridification in North and season of monsoon in South and the Eocene-Oligocene transition (34 Ma)

3. Which phenomenon is the main responsible? Impact of uplift of Tibet

 Paratethys part is about as important as the Tibetan plateau part  BUT : ➔

uplift of Tibetan plateau =

Impact of Paratethys

localized effect, no big

 

changes in big scale ➔

retreat of Parathetys =

regional impact and more significant  

Conclusion Tarim basin : an interesting basin for geologists  formation in a big context of collision

 understanding of phenomenon of endorheism

 origin of one part of aridification and environnemental changes like the climate monsoon-dominant  predict and anticipate climate changes

Tarim basin : an interesting basin for industrialists and politics  a big reservoir of oil ( nearly 15 billions of tons if it is still waterproofness) and gases (70%=methane)  Lop  

Nor : lots of nuclear testing

 predict and anticipate climate changes  

References Articles :  X. Yang et al. Late Quaternary palaeoenvironment change and landscape

evolution

along

the

Keriya

River,

Xinjiang,

China:

the

relationship between high mountain glaciation and landscape evolution in foreland desert regions. INQUA. 2002

 Neil and Houseman. Geodynamics of the Tarim Basin and the Tian Shan in Central Asia. 2007. Tectonics. 

Z.

Zhongshi

et

al.

What

triggers

the

transition

of

palaeoenvironmental patterns in China, the Tibetan Plateau uplift or the Paratethys Sea retreat ? 2007. PALAEO 

E.

Sobel.

Basin

analysis

of

the

Jurassic–Lower

Cretaceous

southwest Tarim basin, northwest China. ANNEE ET REVUE???

 P. E. Rumelhart et al. Cenozoic vertical-axis rotation of the  

Altyn Tagh fault system. 1999. Geology  

References Web-sites :  http://www.encyclopediefrancaise.com/Bassin_de_Tarim.html  http://fr.wikipedia.org/wiki/Bassin_du_Tarim  http://en.wikipedia.org/wiki/Tarim_Basin

 http://fr.wikipedia.org/wiki/D%C3%A9sert_du_Taklamakan  http://en.wikipedia.org/wiki/Lop_Nor

 http://fr.wikipedia.org/wiki/Endor%C3%A9isme  http://en.wikipedia.org/wiki/Tarim_River

 http://en.wikipedia.org/wiki/Kunlun_Mountains  http://en.wikipedia.org/wiki/Pamir

 http://www.gps.caltech.edu/~rkanda/GPS_TienShan2006/GPSFieldTrip_GeologyGuide.htm  http://www.britannica.com/EBchecked/topic/325007/Kunlun-Mountains/47907/Geology

Book :  J.P. Avouac, P. De Wever et al. Himalaya – Tibet, le choc des  

continents. 2002. CNRS Editions.

 

Thanks for your attention ~~~ Any questions ?

 

 

Just for own pleasure...

    Core of a syncline in Miocene (24-25 Ma) sandstone and shale from the western Tarim Basin