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and alluvial gravel. The country has the highest concentration of kimberlite bodies in the world—a total of more than 400, including 343 dikes, 39 pipes and 23 blows. Northern
Lesotho has an average of one kimberlite body for every 10 square kilometers. In spite of the large deposits, very few sites
106:
between the
Molteno and the overlying 70 to 250 meter thick sandstones, mudstones and siltstones of the Elliot Formation, which contains silicified wood and dinosaur fossils. The 15 to 250 meter thick Clarens Formation lies atop the Elliot Formation and has sandstones, siltstones and thin bands of
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are mined and research is ongoing into alluvial deposits. The Karoo
Supergroup hosts low-grade uranium and likely coal and coal-bed methane, although the Lower Karoo which hosts the coal seams does not outcrop in Lesotho. The country has quarrying of
153:. As a result, extreme erosion formed cobble beds with sand and clay layers in lower elevation valleys, with material up to 20 meters thick. Donga is a local term for the steep-sided ravines common in Lesotho that formed in this material.
193:. Dolerite-dike related aquifers have high water productivity in fractures that formed in the surrounding rock due to the high temperature of the intrusion. The sandstones of the
138:. The numerous layers of ropy plateau basalt are intruded by 70 volcanic vents and over 1000 dikes and sills. Kimberlite pipes may have formed during eruptions in the
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crystalline basement rock that formed 3.6 to 2.5 billion years ago. Geologists have gleaned insights into
Lesotho's deep past through extrapolation from South Africa,
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is regarded as the best aquifer in
Lesotho with high yield and frequent springs. Steep terrain, rain and snow melt mean that Lesotho has a high risk of landslides.
28:. The country is notable for large fossil deposits and intense erosion due to high rainfall and a rare case of southern African glaciation during the last ice age.
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412:
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and the sediments of the Karoo
Supergroup were influenced by deformation at three different times before, during and after the formation of the
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130:) cap the sedimentary sequence and form Lesotho's mountain tops, with a 1.6 kilometer thick layer. For the most part, the Lesotho Formation is
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189:
More than 50% of
Lesotho's territory is underlain by fractured igneous rock aquifers, such as the low permeability basalt of the
24:, a section of stable primordial crust. Most of the rocks in the country are sedimentary or volcanic units, belonging to the
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447:
756:
726:
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is the only large fault in the country, running northeast–southwest with a vertical displacement of 300 meters near
82:
and the oldest Karoo-related unit in
Lesotho, with red and maroon sandstones interspersed with thin coal seams. The
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60:
and other data from drilling. Above the ancient basement rocks, almost all of the rocks in
Lesotho are part of the
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Lesotho experienced high rainfall and was one of the few places in southern Africa glaciated during the
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The Karoo
Supergroup began to form 510 million years ago in a rift valley in the south of the
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is built on ancient crystalline basement rock up to 3.6 billion years old, belonging to the
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has extensive diamonds and other natural resources and has the highest concentration of
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fine-grained basalts and sandstones in the Elliot, Molteno and Clarens Formations.
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lake bed environment, with abundant plant and insect fossils. There is an
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98:. The Molteno Formation is 15 to 300 meters thick and records a
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64:, the most widespread stratigraphic unit in southern Africa.
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74:, spanning into what is now southern South America. The
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217:Lesotho has extensive diamond deposits in both
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8:
205:are small or low quality aquifers, but the
181:, although there are other smaller faults.
44:Lesotho shares many commonalities with the
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142:marking an end to volcanic activity.
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165:within the larger southern African
40:Stratigraphy & Geologic History
14:
658:Sahrawi Arab Democratic Republic
428:Democratic Republic of the Congo
240:
157:Structural geology and tectonics
122:enriched volcanic rocks of the
1:
267:. Springer. pp. 140–142.
36:pipes anywhere in the world.
320:. British Geological Survey.
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265:Geological Atlas of Africa
318:"Hydrogeology of Lesotho"
263:SchlĂĽter, Thomas (2008).
413:Central African Republic
213:Natural resource geology
136:tholeiitic magma series
86:is divided between the
78:is the top unit of the
46:geology of South Africa
573:SĂŁo TomĂ© and PrĂncipe
433:Republic of the Congo
203:Burgersdorp Formation
76:Burgersdorp Formation
648:States with limited
292:, pp. 140–142.
134:that cooled from a
757:Geology of Lesotho
359:Geology of Africa
18:geology of Lesotho
744:
743:
675:other territories
448:Equatorial Guinea
228:Drakensberg Group
207:Molteno Formation
195:Clarens Formation
191:Lesotho Formation
128:Drakensberg Group
124:Lesotho Formation
96:Clarens Formation
88:Molteno Formation
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736:
735:(United Kingdom)
731:Tristan da Cunha
727:Ascension Island
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673:Dependencies and
366:Sovereign states
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175:Hellspoort fault
161:Lesotho forms a
92:Elliot Formation
62:Karoo Supergroup
58:kimberlite pipes
26:Karoo Supergroup
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50:Kaapvaal Craton
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248:Geology portal
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116:Early Jurassic
80:Beaufort Group
69:supercontinent
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126:(part of the
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100:Late Triassic
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723:Saint Helena
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598:South Africa
588:Sierra Leone
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393:Burkina Faso
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185:Hydrogeology
160:
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104:unconformity
66:
43:
17:
15:
650:recognition
603:South Sudan
493:Ivory Coast
219:kimberlites
171:Drakensberg
167:Karoo Basin
151:Pleistocene
705:(Portugal)
663:Somaliland
583:Seychelles
548:Mozambique
533:Mauritania
518:Madagascar
473:The Gambia
408:Cape Verde
234:References
224:Quaternary
140:Cretaceous
34:kimberlite
538:Mauritius
54:xenoliths
751:Category
729: /
725: /
718:(France)
712: /
690: /
686: /
638:Zimbabwe
613:Tanzania
463:Ethiopia
458:Eswatini
438:Djibouti
403:Cameroon
388:Botswana
179:Mafeteng
163:syncline
147:Cenozoic
120:amygdale
72:Gondwana
714:RĂ©union
710:Mayotte
701:Madeira
696:(Spain)
692:Melilla
623:Tunisia
593:Somalia
578:Senegal
563:Nigeria
553:Namibia
543:Morocco
508:Liberia
503:Lesotho
453:Eritrea
423:Comoros
398:Burundi
373:Algeria
145:In the
48:, with
30:Lesotho
733:
716:
703:
633:Zambia
628:Uganda
568:Rwanda
523:Malawi
483:Guinea
378:Angola
132:basalt
688:Ceuta
608:Sudan
558:Niger
513:Libya
498:Kenya
478:Ghana
468:Gabon
443:Egypt
383:Benin
109:chert
618:Togo
528:Mali
418:Chad
201:and
114:The
94:and
16:The
753::
297:^
197:,
118:,
111:.
90:,
351:e
344:t
337:v
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