Geothermal Exploration in D.R. Congo

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

1 Geochemical Study of Thermal Springs in Eastern D. R. Congo

• Mambo Vikandy S., (UOR, Butembo) • Kasereka Mahinda, Yalire Mapendano and Wafula Mifundu, (OVG, )

2 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 spi te o f l arge resources, onl y 10% o f population use electricity

3 Index map of the western and eastern rifts in Africa 4 Major ‘Great Lakes’ of the East Africa rifts valleys 5 MjMajor volcanoes and dis tr ibu tion of major 20th Century lava flows 6 The most recent eruption

• Mt.Nyiragongo eruption

– Date : January 17, 2002

– Dea th toll : 100 peop le (60 dea ths by explosion of petrol stations)

– Damages: 30 % of Goma town destroyed or covered with thick lava

7 Vol cani c Disast er in 2002

Lava flow pushes the Lake 100 m as the Lava enters 70 m deep

A house couvered with lava (6 personnes died inside)8 Destruction of Goma town, mostly the business area 9 The most recent major earthquakes

• Kalehe earthquake occured on October 24, 2002 with 12 deaths

•Buk av u ear th quak e on F ebr uar y 3, 2 008 with 44 deaths

10 Damages caused by earthquake in Kalehe (70 km south of Goma) on 24 Oct 2002 11 Earthquake parameters and disaster in Bukavu

● Time ; S und ay F eb . 3 , 2008 07:34 (UT) ● Location; 2.314°S, 28.896°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 Damages of Steeple

Birava, RDC→

←

→ ←

↑Shangi, Rwanda

Nkanka, Rwanda→ 13 Bukavu felt earthquake on Feb. 3, 2008

The eastern border of D.R. Congo: the western branch of EARS. The m ost r ecen tl y r ecor ded sei sm s of m agni tude > 6 ar e al so indicated, with the year of occurrence. 14 Some water samppgling sites

Mayi ya Rwin Makera Moto di Bukom HtHot spr ing o

Nyamulagira

Mpenge Kisuma Tingi KisumaSpring Sake Nyiragongo Cold spring Kihira Rukor Kabuno e Bay Lc

GomaLs R

Lake Kivu Rift limit

Major regional faults

Active Volcanic Centres

Mahyuza Kankule I & II

15 Table 1: Sample and site information

No Site Name Distri ct PiProvince TType LitdLongitude LtitdLatitude Altitud e 1 Uvira Uvira S-Kivu HS 29.07.72E 03.24.33S 855 2 Nyangezi Walungu “ HS 3 Mahyuza Kabare “ HS 28.50.45E 02.14.62S 1552 4 Kankule ““HS 28.50.12E 02.14.94S 1595 5 MibMaziba “ “ HS 12 Muganzo ““HS 6 Mayi ya Moto N-Kivu HS 7 Kambo “ HS 29.40.17E 00.03.77N 1094 8 Masambo ““HS 29.41.75E 00.10.85N 100616 Table 1: Sample and site information (Cont. )

No Site Name Dist ri ct PiProvince TType LitdLongitude LtitdLatitude Altitud e 9 Mutsora Beni N-Kivu HS 29.44.49E 00.18.35E 1094 13 Tingi/Sake Masisi ““ 14 “““CS 15 Kisuma “ “ HS 16 Kisuma Spr ing ““CS 17 Bukomo “““ 18 Kalieri Rutshuru ““ 19 Nyabugezi Rutsh ur u ““ 17 18 Sampling and Analysis

• Date of sampling: – 1994: one samppgling at Ma yyyi ya Moto – 2002-08: other samples • Chem ica l ana lys is: – 1994: in Japan (total analysis) – 2002-2003: Italy (total analysis) – 2008: Goma, OVG (only a few anions)

19 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 Geothermometry

• Analytical data were used to estimate underggpround temperature • Ca not used and no data for SiO2 • Na-KtK temperat ure were cal cul at ed usi ng Truesdell, Fournier & Giggenbach formulas

21 Geothermometry (cont. )

• North-Kivu

• Mayi-ya-moto: 163-177 degree • Tingi-Sake: 229-290 • Kisuma/Masisi: wide discrepency data

22 Geothermometry (cont. )

• South Kivu:

• Muganzo: 339-364 • Kankule: 337-369 • Mahyuza: 345-374 • Maziba: 275-294

23 Conclusion/Recommendations

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

24 Acknowledgements

25 THANK YOU

26