D.R. Congo. Vikandy S. Mambo Université Officielle de Ruwenzori, Butembo, North-Kivu, Eastern Congo

Transcription

1 Geothermal Exploration in D.R. Congo Vikandy S. Mambo Université Officielle de Ruwenzori, Butembo, North-Kivu, Eastern Congo 1

2 Geochemical Study of Thermal Springs in Eastern D.R. Congo Mambo Vikandy S., (UOR, Butembo) Kasereka Mahinda, Yalire Mapendano and Wafula Mifundu, (OVG, Goma) 2

3 Introduction D.R. Congo is known to be endowed with natural resources: Minerals Fresh water Timber Electric power is therefore mainly Hydropower Which enormous untapped resources. In spite of large resources, only 10% of population use electricity 3

4 Index map of the western and eastern rifts in Africa 4

5 Major Great Lakes of the East Africa rifts valleys 5

6 Mj l d di t ib ti f j 20th 6 Major volcanoes and distribution of major 20th Century lava flows

7 The most recent eruption Mt.Nyiragongo eruption Date : January 17, 2002 Death toll: 100 people (60 deaths by explosion of petrol stations) Damages: 30 % of Goma town destroyed or covered with thick lava 7

8 Volcanic Disaster in 2002 Lava flow pushes the Lake 100 m as the Lava enters 70 m deep 8 A house couvered with lava (6 personnes died inside)

9 Destruction of Goma town, mostly the business area 9

10 The most recent major earthquakes Kalehe earthquake occured on October 24, 2002 with 12 deaths Bukavu u earthquake e on February 3, 2008 with 44 deaths 10

11 Damages caused by earthquake in Kalehe (70 km south of Goma) on 24 Oct

12 Earthquake parameters and disaster in Bukavu Time ; Sunday Feb. 3, :34 (UT) Location; S, E, Depth 10 km Birava ( ca 20 km north of Bukavu) Magnitude (M); 6.0 The largest earthquake in south Kivu since 1950 Mechanism ; Normal fault type Crustal block vertically faulting Death toll; RD Congo 7 (1) Rwanda 37 (19) Total 44 (20) 12

13 Damages of Steeple Birava, RDC Shangi, Rwanda Nkanka, Rwanda 13

14 Bukavu felt earthquake on Feb. 3, 2008 The eastern border of D.R. Congo: the western branch of EARS. The most recently recorded seisms s s of magnitude >6 are also indicated, with the year of occurrence. 14

15 Some water sampling sites Bukom o Makera Mayi ya Moto Rwin di Hot spring Kisuma Kisuma Spring Kihira Kabuno Bay Tingi Sake Nyamulagira Lc Nyiragongo Mpenge Rukor e Cold spring Goma Ls Lake Kivu R Rift limit Major regional faults Active Volcanic Centres Mahyuza Kankule I & II 15

16 Table 1: Sample and site information No Site Name Districti Province Type Longitude Ltitd Latitude Altitude 1 Uvira Uvira S-Kivu HS E S Nyangezi Walungu HS 3 Mahyuza Kabare HS E S Kankule HS E S Maziba HS 12 Muganzo HS 6 Mayi ya Moto Rutshuru N-Kivu HS 7 Kambo Beni HS E N Masambo HS E N

17 Table 1: Sample and site information (Cont.) No Site Name District i t Province Type Longitude Ltitd Latitude Altitude 9 Mutsora Beni N-Kivu HS E E Tingi/Sake Masisi 14 CS 15 Kisuma HS 16 Kisuma Spring CS 17 Bukomo 18 Kalieri Rutshuru Rutshuru 19 Nyabugezi u u 17

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19 Sampling and Analysis Date of sampling: 1994: one sampling at Mayi ya Moto : other samples Chemical analysis: 1994: in Japan (total analysis) : Italy (total analysis) 2008: Goma, OVG (only a few anions) 19

20 Chemical Composition All hot spring samples are characterized by high CO2 content. Volcanic gases of Nyirangongo volcano contain almost 50% CO2 inlike other high temperature gases where S02 is the most abundant after H2O Lake Kivu also contain large amount of CO2 and CH4 Suggestion: High CO2 content in hot springs in Eastern Congo is due to magmatic supply 20

21 Geothermometry Analytical data were used to estimate underground temperature Ca not used and no data for SiO2 Na-K Ktemperature t were calculated l using Truesdell, Fournier & Giggenbach formulas 21

22 Geothermometry (cont.) North-Kivu Mayi-ya-moto: degree Tingi-Sake: Kisuma/Masisi: wide discrepency data 22

23 Geothermometry (cont.) South Kivu: Muganzo: Kankule: Mahyuza: Maziba:

24 Conclusion/Recommendations This is a preliminary study showing, on basis of geochemical data that geothermal potential exist Eastern DRC Further investigations are required including: Expand to wider area In-situ measurements of CO2, H2S, discharge rates.. Geological and geophysical surveys Isotope Hydrology 24

25 Acknowledgements 25

26 THANK YOU 26