Ändra sökning
Avgränsa sökresultatet
1 - 5 av 5
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Ali, Ammar A.
    et al.
    College of Engineering, University of Baghdad, Baghdad, Iraq.
    Hassan, Rebwar
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dawood, Anwar Hazim
    College of Engineering, Department of Civil Engineering, Koya University, Koya, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ali, Salahalddin
    Department of Geology, University of Sulaimani, Sulaymaniyah, Iraq. President of Komar University of Science and Technology, Komar University of Science and Technology, Sulaymaniyah, Iraq.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sediment flux from Lesser Zab River in Dokan Reservoir: Implications for the sustainability of long‐term water resources in Iraq2020Ingår i: Rivers Research and Applications: an international journal devoted to river research and management, ISSN 1535-1459, E-ISSN 1535-1467, Vol. 36, nr 3, s. 351-361Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Prudent management of Iraqi water resources under climate change conditions requires plans to be based on actual figures of the storage capacity of existing reservoirs. With the absence of sediment flushing measures, the actual storage capacity of Dokan Reservoir (operated since 1959) has been affected by the amount of sediment delivered during its operational life leading to an undetermined reduction in its storage capacity. In consequence, there has not been an update on the dam's operational storage capacity curves. In this research, new operational curves were established for the reservoir based on a recent bathymetric survey undertaken in 2014. The reduction in reservoir capacity during the period between 1959 and 2014 was calculated by the mean of the difference between the designed storage capacity and the storage capacity which was concluded from the 2014 bathymetric survey. Moreover, the rate of sediment transported to the reservoir was calculated based on the overall quantities of accumulated sediment and the water discharge of the Lesser Zab River into the reservoir. The results indicate that the dam capacity is reduced by 25% due to sedimentation of an estimated volume of 367 million cubic metres at water level 480 m.a.s.l. The annual sedimentation rate was about 6.6 million cubic metres, and the sediment yield was estimated to be 701.2 t∙km−3∙year.

  • 2.
    Hassan, Rebwar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ali, Ammar A.
    College of Engineering, University of Baghdad, Baghdad, Iraq.
    Ali, Salahalddin S.
    Department of Geology, University of Sulaimani, Sulaymaniyah, Iraq.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Bathymetry and siltation rate for Dokan Reservoir, Iraq2017Ingår i: Lakes & Reservoirs: Research and Management, ISSN 1320-5331, E-ISSN 1440-1770, Vol. 22, nr 2, s. 179-189Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Dokan Reservoir dam is a concrete cylindrical arch with gravity abutments, located on the Lesser Zab River about 60 km from the city of Sulaimani in north-eastern Iraq. A bathymetric survey was conducted in November 2014 for a period of 10 days, using an echo sounder of 200-kHz single beam. The survey results indicated an annual average sediment deposition of 3.8 million m3. Thirty-two sediment samples were collected from the reservoir bed. The ratio of gravel, sand, silt and clay was 15:14:48:23, respectively. The reservoir bed is covered mainly with silt. The sediments are composed of silty clay (77.6%), silty sandy clay (10%), sandy gravely silty clay (1.2%) and gravely sandy silty clay (1%).

  • 3.
    Hassan, Rebwar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ali, Salahaddin S.
    Department of Geology, University of Sulaimani, Sulaymaniyah, Iraq.
    Ali, Ammar A.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Abdullah, Twana
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dukan Dam Reservoir Bed Sediment, Kurdistan Region, Iraq2016Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 9, s. 582-596Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Dukan Dam Reservoir (DDR) in the Kurdistan Region of Iraq has been studiedto determine the characteristics and nature of the reservoir and the deposited sedimentson its bottom surface. This study was achieved by doing a field survey andgrain size analyses of the collected sediment samples at 32 locations representing thewhole reservoir area that had been created when the Lesser Zab River was dammedin 1959. The Dukan Dam, which is a multi-purpose concrete arch dam, was built onthe Lesser Zab River for controlling its flood during high rainfall seasons, irrigationand power generation. The catchment area is 11,690 km2. The surface area of the reservoiris 270 square kilometers and the volume is 6.870 × 106 m3 at normal operationlevel (El. 511.00 m. a.s.l.). The minimum drawdown level is at elevation 469 mabove sea level (a.s.l.). The live storage is 6.14 × 106 m3 while the remainder is deadstorage. The reservoir has a surface area that reaches 270 square kilometers and iscomposed of two sub-reservoirs connected by a narrow channel that has a length of 5kilometers. The relatively bigger reservoir is located in the north and has a triangularshape with a surface area approximately 250 square kilometers. The smaller sub-reservoiris located down south where the dam exists and it has irregular rectangularshape. Thirty-two sediment samples were collected from the bottom of Dukan reservoir.The bed of the reservoir is mainly composed of 15% gravel, 14% sand, 48%silt and 23% clay respectively. Most of the sediments are very fine grained, verypoorly sorted, strongly coarse skewed and mesokurtic.

  • 4.
    Hassan, Rebwar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ali, Ammar
    Hazim, Anwer
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Reduction in the Storage Capacity of Dokan Dam Reservoir2019Ingår i: Advances in Sustainable and Environmental Hydrology, Hydrogeology, Hydrochemistry and Water Resources: Proceedings of the 1st Springer Conference of the Arabian Journal of Geosciences (CAJG-1), Tunisia 2018 / [ed] Helder I. Chaminé, Maurizio Barbieri, Ozgur Kisi, Mingjie Chen, Broder J. Merkel, Switzerland: Springer Nature , 2019, s. 429-432Konferensbidrag (Refereegranskat)
    Abstract [en]

    Dokan reservoir is located on the Lesser Zab River NE Iraq. Its drainage area is 11,690 km2 with a storage capacity of 6.87 × 109 m3. Calculation of the volume of the reservoir before the construction of the dam and from the bathymetric survey conducted in 2014 indicates that an annual average of 7 million cubic meters of sediments are deposited within the reservoir. This reduced the storage capacity of the reservoir by 28%.

  • 5. Sissakian, Varoujan
    et al.
    Ahad, Ayda Abdul
    Iraq Geological Survey, Baghdad.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Hassan, Rebwar
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    The Regional Geology of Dokan Area, NE Iraq2016Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 6, nr 3, s. 35-63Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The northern and northeastern part of Iraq, which includes the Iraqi Kurdistan Region, is characterized by mountainous area with very rugged relief. The difference in relief may reach up to 1000 m and locally more when the height reaches up to 3600 m (a.s.l.). The mountains usually represent anticlines, whereas the depressions are represented by synclines. The Lower Cretaceous rocks usually form the carapace of the mountains, whereas the soft clastics of Upper Cretaceous and Paleocene form the synclines. However, some exceptions occur when the area is affected structurally by main faults. The main trend of the anticlines in the study area is NW – SE, which are dissected by either NE – SW normal faults or by reverse and/ or thrust faults oriented in NW – SE trend; however, some exceptions occur too. The Dokan area is characterized by a large depression in which the Lesser Zab River was flowing; before construction of Dokan dam (1954 – 1959). The depression is a big one with surface area of about 260 Km2. The height at the surface of the reservoir when filled to normal operational level is 511 m (a.s.l.); however, the depression is surrounded; almost from all sides by high mountains that range from (800 – 1300) m (a.s.l.).he depression is believed to be structurally controlled, a normal fault with NE – SW trend had dissected the southwestern limb of Ranya anticline, the eastern block being the down thrown one that had formed the depression, besides the exposure of soft rocks of Sarmord, Chis Gara, Barsarin and Naokelekan formations that form the core of Ranya anticline. The regional geology of Dokan area including structure and tectonics, stratigraphy and geomorphology is discussed aiming to explain the development of the large and wide depression in a mountainous area.

1 - 5 av 5
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf