ANNEXURE TABLE 3: LOCATION AND ROAD BUILDING PROPERTIES OF ROCKS IN NAMIBIA

VAALIAN AND MOKOLIAN ROCK

|=================================================================================================================|
| AGE/     | GROUP/   | FORMATION/| LITHOLOGY: SEDIMENTARY,      | PROPERTIES: APPLICATIONS AND EXPERIENCES       |
| SEQUENCE | SUBGROUP |COMPL/SUITE| VOLCANIC AND INTRUSIVE ROCKS |                                                |
|----------------------------------------------------------------|------------------------------------------------|
| VAALIAN ERATHEM: ISOTOPIC AGE: >2.100 Ma TO 2.000 Ma           |                                                |
|----------------------------------------------------------------|                                                |
| >2.100 Ma|          | Epupa     | Paragneiss,metasedimentary.  |  No systematic experience as road building     |
|          |          | Complex   |                              |  material as yet.                              |
|          |          | (Ve)      |                              |                                                |
|----------|----------|-----------|------------------------------|                                                |
| 2.100 Ma |          | Kunene    | Anorthosite,dunite,gabbro,   |                                                |
|          |          | Complex   | norite,syenite,foyaite.      |                                                |
|          |          | (Vk)      | intrusive into Epupa and     |                                                |
|          |          |           |                   older      |                                                | |----------------------------------------------------------------|------------------------------------------------|
| MOKOLIAN ERATHEM: ISOTOPIC AGE: 2.000 Ma TO 1.000 Ma           |                                                |   |----------------------------------------------------------------|------------------------------------------------|
| 2.000 Ma | Haib (Mh)|           | Andesite,dacite,rhyolite.    |                                                |
|----------|----------|-----------|------------------------------|                                                |
| 1.960 to |          |Vioolsdrift| Granodiorite,leucogranite,   |  Not very much is known about the road         |
| 1.810 Ma |          | Suite     | gabbro,diorite.              |  building properties of these rocks.           |
|          |          | (Mgv)     | intrusive into Haib and      |                                                |
|          |          |           | older                        |                                                |
|----------|----------|-----------|------------------------------|------------------------------------------------|
| 1.800 Ma |          |Huab,Grootf| Para-/orthogneiss,granite,  ,| A paragneiss of the Hohewarte Formation found  |
|and older |          | Abbabis,  | metabasite dykes,            | between Oamites and Brack was used for the     |
|          |          | Hohewarte,| metasedimentary rocks.       | subbase of TR 1/5 between Rehoboth and Aris    |
|          |          | Mooiriver,| (Mhu,Mgr,Mab,Mho,Mmo,Mnh)    | with no negative experiences on record for     |
|          |          | Neuhof    |                              | these rocks.                                   |
|----------|----------|-----------|------------------------------|------------------------------------------------|
| 1.800 Ma |Khoabendus| Okapuka,  | Rhyolite,basalt,andesite,    |                                                |
|          |  (Mk)    |   (Mok)   |ortho-amphibolite,greenschist | Only randomly used. No systematic experiences  |
|          |          | Elim (Me) |quartzite,phyllite,limestone, | known.                                         | |          |          |           | magnetite-quartzite,gneiss.  |                                                |
|----------|----------|-----------|------------------------------|------------------------------------------------|
| 1.860 to |          | Franzfont-| Granite,granodiorite.        | Only randomly used for gravel wearing courses  |
| 1.730 Ma |          | ein Suite | intrusive into Khoabendus    | in Damaraland. No systematic experiences on    |
|          |          |   (Mgf)   | Group and Huab               | record.                                        |
| Rehoboth |          | Marienhof | Quartzite,phyllite,weakly    | The Rehoboth Sequence granites which intruded  |
| Sequence |          | (Mm)      |metamorphosed basalt,rhyolite | older formations like Mk and the paragneisses  |
| 1.670 to |          |Gaub Valley| and conglomerate.            | of Mh were used for the basecourses for TRs    |
| 1.420 Ma |          | (Mvy)     |Quartzite,schist,conglomerate | 1/4 and 1/5 and gravel wearing courses:        |
|          |          | Billstein | and quartz porphyry.         | Rehoboth west area: No negative experiences.   |
|          |          | (Mbi)     |                              |                                                |
|          |          |           |  Metabasite dykes. (Mm,Mvy)  |                                                |
|          |          |           | intrusive into Gaub & older  | Nothing is known about the road properties     |
|----------|----------|-----------|------------------------------| of these rocks.                                |
| 1.500 Ma |          | Alberta   |Ortho-amphibolite,anorthosite |                                                |
| minimum  |          | Doornboom | serpentinite,hornblendite,   |                                                |
|          |          | Complexes | talc and chlorite schist.    |                                                |
|          |          | (Mal,Mu)  | intrusive into Gaub & older  |                                                |
|          |          | Piksteel  | Granodiorite,quartz diorite. | No systematic experiences are on record        |
|          |          | Weener    |                              | for these rocks.                               |
|          |          | (Mgp,Mge) | intrusive into Gaub & older  |                                                |
|----------|----------|-----------|------------------------------|------------------------------------------------|
|          |          |Namaqualand|                              |                                                |
|          |          |Metamorphic|                              |                                                |
|          |          |Complex    |                              |                                                |
|          |          |  (Mn)*    |                              |                                                |
|          |          |           |                              |                                                |
|>1.200 Ma |          |  (Mp)     |Gneiss,metasedimentary rocks ,| No systematic experiences are on record        |
|          |          |           | ortho-amphibolite.           | for these rocks.                               |
|          |          |           |                              |                                                |
|          |          |  (Mgj)    | Charnockite,gabbronorite,    | Some granites and gneisses have favourable     |
|          |          |           | ultramafic rocks.            | road construction properties and they have     |
|±1.200 Ma |          |  (Mgb)    | Biotite-rich augen gneiss.   | been used for the basecourse construction      |
|          |          |           |                              | for TR 4/2: Lüderitz-Aus and also for coarse   |
|          |          |  (Mgw)    | Gneissic granite,pegmatite.  | concrete aggregate with good successes.        |
|          |          |           |                              | However, soluble salt contents need to be      |
|          |          |           | all are intrusive into Mp    | watched.                                       |
|----------|----------|-----------|------------------------------|------------------------------------------------|
| Sinclair |          | Tumuab    | Granites                     |                                                |
| Sequence |          |  (Mgt)    | intrusive into older         |                                                |
| 1.300 to |----------|-----------|------------------------------|                                                |
| 1.000 Ma |          | Nagatis   | Rhyolite,quartz porphyry,    | No systematic experiences.                     |
|          |          |  (Mna)    | arkose,shale,basalt.         |                                                |
|          |----------|-----------|------------------------------|------------------------------------------------|
|          |          | Houmoed   |Granodiorite,diorite,granite  | No systematic experiences.                     |
|          |          |  (Mgh)    | intrusive into Mna.          |                                                |
|          |----------|-----------|------------------------------|------------------------------------------------|
|          |          | Kunjas    | Conglomerate,arkose,shale,   |                                                |
|          |          |  (Mku)    | quartzite.                   | Randomly used for some gravel wearing courses  |
| 1.265 Ma |          | Barby     | Basalt,andesite,arkose,tuff  | No systematic experiences.                     |
|          |          |  (Mba)    |felsite,conglomerate,quartz.  |                                                |
|          |----------|-----------|------------------------------|------------------------------------------------|
|          |          | Nubib(Mgn)| Granite.                     | No systematic experiences.                     |
|          |          | Spes Bona | Syenite,diorite,monzonite    |                                                |
|          |          |  (Msy)    |intrusive into Barby & older. |                                                |
|          |----------|-----------|------------------------------|------------------------------------------------|
|          |          |Guperas(Mg)| Rhyolite,ignimbrite,basalt,  | No systematic experiences.                     |
|          |          | Nuekopf   | conglomerate,shale,quartzite.|                                                |
|          |          |  (Mnu)    |                              |                                                |
|          |----------|-----------|------------------------------|------------------------------------------------|
| 1.210 to |          | Gamsberg  | Granite intrus. into Nuekopf | Randomly used for gravel wearing courses.      |
| 1.160 Ma |          | Suite     | and older.                   |                                                |
|          |          | Sonntag   | Granite: intrusive into      | No systematic experiences.                     |
|          |          |(Mgg + Mgs)| Guperas and older.           |                                                |
|          |----------|-----------|------------------------------|------------------------------------------------|
|          |          |Aubures(Ma)| Quartzite and red quartzite, | The red quartzites and conglomerates of the    |
|          |          | Grauwater | conglomerate,shale,basalt,   | Doornpoort Sub-formation can be found around   |
|          |          |  (Mga)    |rhyolite,ignimbrite,argillite | Witvley and Gravenstein. The red quartzites    |
|          |          |Doornpoort |                              | were used as crusher-run basecourse for        |
|          |          |  (Md)     | Formations from Grauwater    | TR 6/1 between Witvley and Gobabis and also    |
|          |          | Klein Aub | to Klein Aub are the equiv.  | for coarse concrete aggregate with favourable  |
|          |          |  (Mka)    | in the Rehoboth/Witvley      | experiences. Also randomly used for gravel     |
|          |          |           | areas to the Sinclair Sequ.  | wearing courses in the Gobabis area.           |
|----------|----------|-----------|------------------------------|------------------------------------------------|
| 920 Ma   |          | Richters- | Granite (Ngr),Syenite (Nsy)  | Due to remoteness in extreme south-western     |
|          |          | feld      | intrusiv into older          | corner in Namibia no systematic experiences    |
|          |          | Complex   | formations.                  |                                                |
|=================================================================================================================|

NAMIBIAN AND CAMBRIAN ROCKS
|=================================================================================================================|
|     AGE/ | GROUP/   | FORMATION/| LITHOLOGY: SEDIMENTARY,       | PROPERTIES: APPLICATIONS AND EXPERIENCES      |
| SEQUENCE | SUBGROUP |COMPL/SUITE| VOLCANIC AND INTRUSIVE ROCKS  |                                               |
|-----------------------------------------------------------------|-----------------------------------------------|
|NAMIBIAN/CAMBRIAN ERATHEMS: ISOTOPIC AGES: +/-1.000 Ma TO 450 Ma |                                               |
|-----------------------------------------------------------------|-----------------------------------------------|
| Damara   | Nosib    |            |                              |Nosib quartzite: MR 92: near Ruacana: very     |
| Sequence | (Nn)     |            |                              |hard and little affected by weathering: is     |
|          |(Central) |            |                              |visible as reddish rock with layers and lenses |
| 850 to   |          | Nauuwpoort |Metamorph.acid volcanic rocks |of conglomerate in road excavations.           |
| 700 Ma   |          | (Nnp)      |(Nn);alk.ingnimbrite+rhyolite |Nosib quartz was used for fill layers and      |
|          |          |            |quartzite,conglomerate,schist |selected layers (subbase and basecourse) with  |
|          |          |            |minor andesite,bostonite(Nnp) |good results on MR 67/MR 92: near Ruacana.     |
|          |          |            |                              |Premix aggregate: TR 1/11: Oshivelo-Ondangwa   |
|          |          |            |                              |with satisfactory results.                     |
|          |          |------------|------------------------------|(experience for Nosib: northern zone)          |
|          |          | Duruchaus  | (Ndu,Nka,Nb and Nsb)         |                                               |
|          |          | Kamtsas    |Quartzite,conglomerate,schist |Further no systematic experiences.             |
|          |          | Blaubeker  |marble mixtite.               |                                               |
|          |          |Spencer Bay |                              |                                               |
|          |          |------------|------------------------------|-----------------------------------------------|
| 900 to   |          |Nauuwpoort  |Subvolcanic bostonite,syenite | No systematic experiences reported.           |
| 720 Ma   |          | (Nnp)      | foyaite,gabbro.              |                                               |
|          |          |            | intrusive into Nn and older. |                                               |
|          |          |            |                              |                                               |
|          |----------|------------|------------------------------|-----------------------------------------------|
|          | Nosib    | Askevold   | Epidosite,agglomerate        | Nosib quartz Nn forms in the north-east of    |
|          | (Nn)     | (Nas)      |                              | Namibia near Andara/Okavango the only source  |
|          |(Northern)| Varianto   | Mixtite,quartzite,schist,    | of crusher-run basecourse material, was also  |
|          |          | (Nv)       | conglomerate,dolomite.       | used as concrete aggr. for Bagani Bridge.     |
|----------|----------|------------|------------------------------|-----------------------------------------------|
| 900 to   | Swakop   |            |                              | No systematic experiences reported.           |
| 700 Ma   |(Central) |            |                              |                                               |
|          |Ugab (Nu) |            | Marble,schist,quartzite,     |                                               |
|          |Kudis(Nku)|            | graphitic schist.            |                                               |
|          |----------|------------|------------------------------|-----------------------------------------------|
|          | Khomas   | Chuos      |Mixtite,schist,iron-formation | Calcareous and dolomitic marbles of Karibib,  |
|          |(Central) | (Nc)       |ortho-amphibolite,quartzite,  | Usakos and Swakopmund used for surfacing      |
|          |  Ugab,   | (Central)  |graphitic schist.             | chips and concrete aggregates.                |
|          |Kudis and | Karibib    |Marble,ortho-amphibolite,     | Due to absence of other suitable road buil-   |
|          |Khomas are| (Nkb)      |quartzite.                    | ding materials biotite mica schist is used.   |
|          |sub groups| Auas (Nau) |Schist,quartzite.             | as gravel for subgrade and subbase layers     |
|          |          | Kuiseb     |Mica schist;marble (Nge),     | for paved roads but avoided as basecourse,    |
|          |          | (Nk)       |quartzite,graphitic schist,   | also as wearing coarse for gravel roads: test |
|          |          |            |Calcsilicate (Nti: Tinkas     | sections on MR 49 with surprisingly good      |
|          |          |            |Member).                      | successes.                                    |
|          |          |            |Ortho-amphibolite (Nml:       | For many road projects in the Windhoek area   |
|          |          |            |Matchless Member).            | mica schist was successfully used as selected |
|          |          |            |Nsc* comprises Nu,Nku,Nc,Nkb, | subgrade, often blended with quartz gravel.   |
|          |          |            |and Nau.                      | For gravel wearing courses it was found that  |
|          |          |            |Nd* comprises Nosib and       | mica schists need less maintenance than       |
|          |          |            |Swakop Groups.                | quartzitic gravels (Tests: MR 49). Cracking   |
|          |          |            |                              | problems: formation: MR 52: Windhoek-Keres.   |
|----------|----------|------------|------------------------------|-----------------------------------------------|
| Damara   | Otavi    |            | Dolomite,limestone,shale,    | Dolomites of Otavi Group have typical karst   |
| Sequence | (No)*    |            | quartzite.                   | features with possibilities of sinkholes:     |
| 900 to   |(Northern)|            |                              | example: TR 1/9 on farm Ubi Bene 768.         |
| 700 Ma   |Abenab(Na)|            |                              |                                               |
|          |Tsumeb(Nt)|            | Dolomite,limestone,shale,    |                                               |
|          |Abenab +  |            | chert.                       | Dolomites quarried at Grootfontein, Tsumeb,   |
|          |Tsumeb are| Chuos (Nc) | Mixtite,shale,quartzite      | Otavi and Outjo for surfacing chips and       |
|          |sub groups|(Northern)  | No* comprises Na and Nt.     | coarse concrete aggregates.                   |
|          |          |            |                              | Limestone crushed for base on TR 1/10.        |
|----------|----------|------------|------------------------------|-----------------------------------------------|
| 650 to   |Mulden(Mn)|            | Phyllite,quartzite,schist    | Engineering properties of Mulden rocks not    |
| 570 Ma   |(Central &|            | conglomerate                 | well known, but phyllites successfully used   |
| 570 Ma   |Northern) |            |                              | for basecourse, subbase: TR 8/1: Otavi.       |
|----------|----------|------------|------------------------------|-----------------------------------------------|
| 650 to   |          | (Ngl)      | Gneissic leucogranite.       | Weathered Salem granite of a pegmatitic type  |
| 470 Ma   | (Cgd)*   |Salem Suite | Granite,granodiorite,diorite | was used with no negative experiences so far  |
|          | Granites | (Cgs)      | monzonite.                   | for selected subgrade and subbase for the     |
| 560 to   |from Salem| Sorris-    | Red granite: gneissic.       | building of TR 2/3 between Karibib and        |
| 510 Ma   | to       | Sorris     |                              | Omaruru.                                      |
|          |Dachsberg | (Cgss)     |                              |                                               |
|          |          | Ozombanda  | Red granite: homogeneous.    |                                               |
|          |          | (Cgo)      |                              |                                               |
|          |          |both: (Cgl)*|                              |                                               |
| 530 to   |          | Donkerhoek | Granite,alask., pegmatitic.  |                                               |
| 470 Ma   |          | (Cgdh)     |                              |                                               |
|          |          |  Dachsberg | Quartz diorite.              |                                               |
|          |          | (Cgdb)     |                              |                                               |
|          |          |both: (Cgi)*| Serpentinite,schist,silcrete |                                               |
|          |          | (Cu)       | Gabbro,norite.               |                                               |
| 530 Ma   |          | (Cnd)      | All 3 complexes:             |                                               |
|          |           | Haruchas   | Granite (Cgr),syenite.(Csy) |                                               |
|          |          | Bremen     | Bostonite.(Cbo)              |                                               |
| 500 Ma   |          | Tatasberg  | Diatremes and sills:alnoitic |                                               |
|          |          | Complexes  | tuffisite.                   |                                               |
|          |          | Garub      | All granites:intrusive into  |                                               |
|          |          | Suite      | Damara Sequence and older.   |                                               |
|----------|----------|------------|------------------------------|-----------------------------------------------|
| 530 to   |          | Naukluft   |                              |                                               |
| 500 Ma   |          | Nappe      |                              |                                               |
|          |          | Complexes  |                              |                                               |
|          |LowerNappe| Rietoog    | Quartzite,black limestone,   |                                               |
|          |          | Nappe (Nr) | conglomerate,shale,dolomite  | Not systematically tested as yet.             |
|          |UpperNappe| Dassie     | Limestone,dolomite,shale.    |                                               |
|          |          | Nappe (d)  |                              |                                               |
|          |          | Zebra      | Quartzite,black limestone,   |                                               |
|          |          | Nappe (z)  | conglomerate,shale,dolomite  |                                               |
|          |          | Pavian     | Dolomite,shale,conglomerate. |                                               |
|          |          | Nappe (p)  |                              |                                               |
|          |          | Kudu       | Dolomite,limestone,shale,    |                                               |
|          |          | Nappe (k)  | conglomerate.                |                                               |
|----------|----------|------------|------------------------------|-----------------------------------------------|
| 650 to   |          | Gariep     |                              |                                               |
| 500 Ma   |          | Complex    |                              |                                               |
|          |          | Rosh Pinah | Felsite,tuff,quartzite,schist| As a result of the remoteness of this area    |
|          |          | (Nrp)      |                              | and the fact that due to political reasons no |
|          |          | (Ng)*      | Dolomite,shale,schist,ortho+ | direct connections between the RSA controlled |
|          |          |            | para-amphibolite,quartzite,  | diamond concern 'CDM' and the Namibian        |
|          |          |            | intraformational mixtite,grit| concern exist very little is known about the  |
|          |          | Numees Nmu | basal mixtite,Numees mixtite.| engineering properties of these rocks.        |
|----------|----------|------------|------------------------------|-----------------------------------------------|
| 600 to   | Nama     |            |                              |                                               |
| 450 Ma   |          |            |                              |                                               |
|          | Kuibis   |            | Sandstone,black limestone,   | Quartzites and sandstones are suitable: coarse|
|          | (Nks)    |            | conglomerate,shale.          | concrete aggr. Quartz rich varieties of silt- |
|          |----------|------------|------------------------------| stone can be used for rockfills.              |
|          | Schwarz- |            | Green+red shale,sandstone.   | (Niederhagen quartzites).                     |
|          | rand     |            |                              |                                               |
|          | (Ns)     | Huns Nh    | Limestone.                   | Slabby nature of Nasep sandstone: less        |
|          |----------|------------|------------------------------| suitable for road construction.               |
|          |FishRiver | Stockdale  | Red sandstone and shale.     | Ns: Red sandstone: suitable for coarse        |
|          |(Kuibis,  | (Cs)       |                              | concrete aggregate.                           |
|          | Schwarz- | Breckhorn  | Red and grey sandstone and   | Rosenhof member of Cg: slightly slabby red    |
|          | rand     |            |                              |                                               |
|          | and Fish | (Cb)       | shale.                       | shales with red sandstones: suitable for      |
|          | River are| Nababis    | Red sandstone and shale.     | concrete aggregate and rock fills.            |
|          |subgroups)| (Cn)       |                              | Problems of all Nama rocks:                   |
|          |          | Gross Aub  | Red shale and sandstone.     | High soluble salt contents.                   |
|          |          | (Cg)       |                              | Ns solid sandstones and shales: MR 34 and     |
|          |          |            |                              | TR 3/1 for natural basecourses and coarse     |
|          |          |            |                              | concrete aggregates.                          |
|          |          |            |                              | Also favourable for gravel wearing courses:   |
|          |          |            |                              | MR 31:especially for areas with high N-values |
|          |          |            |                              | but tend to be slippery during rains.         |
|=================================================================================================================|
NOTA: '* ' means "stratigraphy undifferentiated"; 'COMPL' means COMPLEX;
'**' means no specific subgroup or formation has been identified so far

KAROO ROCKS
|=================================================================================================================|
| AGE/     | GROUP/   | FORMATION/| LITHOLOGY: SEDIMENTARY,       | PROPERTIES: APPLICATIONS AND EXPERIENCES      |
| SEQUENCE | SUBGROUP |COMPL/SUITE| VOLCANIC AND INTRUSIVE ROCKS  |                                               |
|-----------------------------------------------------------------|-----------------------------------------------|
| CARBONIFEROUS/CRETACEOUS ERATHEMS:ISOTOPIC AGES: 400 Ma TO 70 Ma|                                               |
|-----------------------------------------------------------------|-----------------------------------------------|
| Karoo    |          | Dwyka (Cd) | Tillite,boulder shale,shale, |Tillites:Good for natural basecourses: TR 1/3, |
| Sequence |          |            | sandstone,limestone.         |TR 4/1, also favourable for subgrade layers:   |
| 400 to   |          |            |                              |TR 1/3 and TR 5/1 also for gravel wearing c.:  |
| 120 Ma   |          |            |                              |MR 27 but not for surfacing chips (flakiness). |
|          |----------|------------|------------------------------|-----------------------------------------------|
|          | Ecca     | Prince     | Shale,mudstone,sandstone.    |Karoo sandstones: Unfavourable as coarse       |
|          | sub group| Albert(Pp) | Nossob (Pn); Auob (Pau).     |concrete aggregates, baked shales are more     |
|          |          | Whitehill  | Carbonaceous shale.          |suitable: bridges 205,211 on TR 1/3. Sandstone |
|          |          | (Pw)       |                              |can be used as natural basecourse provided it  |
|          |          |Aussenkjer  | Shale, limestone, siltstone. |has a 10% FACT (Fines Aggregate Crushing Test) |
|          |          | (Pa)       |                              |larger than 140 kN.Mudrocks play a great role  |
|          |          | Amibberg   | Sandstone, mudstone, shale.  |in the south.Conglomerates of sandstones,til-  |
|          |          | (Pm)       |                              |lites and shales were used favourably as base  |
|          |          |            |                              |course on TRs 1/3,1/2 and 4/1. Sandstones,     |
|          |          |            |                              |shales,mudrocks favourable as subgrades: TR 3/1|
|          |          |            |                              |Shales and mudrocks favourable as gravel       |
|          |          |            |                              |wearing courses: MRs 25,30,39. Problems:TR 1/3:|
|          |          |            |                              |Itzawisis:weak subsurface drainage. Sandstone  |
|          |          |            |                              |gravel wearing courses due to weak PI and lack |
|          |          |            |                              |of binder on isolated gravel roads:south-east. |
|          |          |            |                              |Baked shales:not suitable for surfacing chips. |
|          |----------|------------|------------------------------|-----------------------------------------------|
|          |          | Gai-As(TRg)| Red mudstone,siltstone,grit, |TRo sandstone: good as subbase/basecourse on   |
|          |          | Omingonde  | sandstone,conglomerate       |TR 1/11 and MR 92 and rehabilitation:TR 1/7.   |
|          |          | (TRo)      | From Ecca to Omingonde:      |It was also favourably used for surfacing      |
|          |          |            | CTR*                         |chips (indurated mudrocks).                    |
|          |          |------------|------------------------------|-----------------------------------------------|
|          |          | Etjo Je    | Aeolian sandstone.           |                                               |
|          |          |            |                              | Not systematically tested as yet.             |
|          |          |            |                              |                                               |
|          |          |            |                              |                                               |
|          |----------|------------|------------------------------|-----------------------------------------------|
| 180 Ma   | - (**)   |(Jd)and(Jr) | Extrusive dolerite+rhyolite   |Volcanic Karoo rock good for surfacing chips  |
|          |          | (**)       |into Karoo Sequence and older |and coarse concrete aggregate:TR 5/1 and MR 61 |
| 180 Ma   |          | Kalkrand   | Basalt, minor sandstone.     |Ke basalts with high PI are good as wearing    |
| 120 Ma   |          | (Jk)       | (Je)*                        |course for salt-gypsum roads along the coast   |
|          |          | Etendeka   | High-silica basalt,latite,   |of the Damaraland, although not systematically |
|          |          | (Ke)       | quartz latite,minor aeolian  |tested yet but unfavourable as gravel wearing  |
|          |          |            | sandstone.                   |course for district roads in the interior.     |
|          |          |            |                              |Karoo dolerite successfully used:coarse concr. |
|          |          |            |                              |aggr. all over the south, surfacing chips for  |
|          |          |            |                              |nearly all paved roads in the south, as        |
|          |          |            |                              |crusher-run and natural basecourse on TR 1/1   |
|          |          |            |                              |and TR 1/7, weathered dolerite as subbase/sub- |
|          |          |            |                              |grade on many paved roads in the south, also   |
|          |          |            |                              |used with good results as gravel wearing       |
|          |          |            |                              |course: MR 21, 22 and 30 and many others.      |
|-----------------------------------------------------------------|-----------------------------------------------|
|CARBONIFEROUS/CRETACEOUS ERATHEMS: ISOTOPIC AGES: 400 Ma TO 70 Ma|                                               |
|-----------------------------------------------------------------|-----------------------------------------------|
|+-< 100 Ma|          | Post Karoo | Granite (Kgr),syenite (Ksy), |                                               |
|          |          | Complexes  | foyaite(Kfo),granophyre(Kgy),| Not systematically tested as yet.             |
|          |          |            | rhyolite (Krh),tuff (Ktu),   |                                               |
|          |          |            | breccia (Kbr),diorite (Kdi), |                                               |
|          |          |            | picrite (Kpi),gabbro (Kg),   |                                               |
|          |          |            | pyroxenite(Kpy),diatreme (*) |                                               |
|          |          |            | intrusive into older rocks.  |                                               |
|----------|----------|------------|------------------------------|-----------------------------------------------|
|          |          | Pomona     | Marl,grit,conglomerate,      |                                               |
|          |          | (Kp)       | chalcedonic limestone.       | Not systematically tested as yet.             |
|          |          |            | Breccia of Brukkaros Mountain|                                               |
|          |          |            | Kimberlite intrusive         |                                               |
|          |          |            | into older rocks.            |                                               |
|=================================================================================================================|
NOTA: '* ' means " stratigraphy undifferentiated"; 'COMPL' means COMPLEX;
'**' means no specific subgroup or formation has been identified so far
10% FACT: The "10% Fines Aggregate Crushing Value" is the force in kN required to crush a sample of
-13,2 -9,5 mm aggregate so that 10% of the total test sample will pass a 2,36 mm sieve.

TERTIARY AND QUATERNARY ROCKS
=================================================================================================================|
| AGE/      | GROUP/     | FORMATION/| LITHOLOGY: SEDIMENTARY,     | PROPERTIES: APPLICATIONS AND EXPERIENCES     |
| SEQUENCE  | SUBGROUP   |COMPL/SUITE| VOLCANIC UND INTRUSIVE ROCKS|                                              |  |------------------------------------------------------------------|----------------------------------------------|
| TERTIARY TO QUATERNARY ERATHEMS: ISOTOPIC AGES: FROM 65 Ma       |                                              |
|------------------------------------------------------------------|----------------------------------------------|
|           |             |Tertiary(T)| Marine clay,marly sandston | Phonolite is a hard rock which in its fresh  |
|39 to 32 Ma|             |Auas Mount.| Phonolite,trachyte (Tr)    | state is extensively quarried at Aris, south |
|           |             |Klinghardt | intrusive into older rocks.| of Windhoek. It is used as a high quality    |
|           |             |Mountains  |                            | surfacing aggregate for most of the paved    |
| Kalahari  |             |(Tk) & (Pp)| Suboutcrops under Tk and Qn| roads in the vicinity of Windhoek as far     |
| Tk        |             |           |+ other superficial deposits| south as Mariental and as far north as Sukses|
|           |             |           | (e.g.: Pp).                | between Okahandja and Otjiwarongo.           |
|           |             | (Tn)      | Calcrete terraces+red,part.| Kalahari sands: uniform grading with good    |
|           |             |           | consol.dune deposits:Namib | CBRs and binding properties: suitable for    |
|           |             | (Tk)      | Sand,calcrete and gravel of| road layers and asphalt aggregate but        |
|           |             |           | Kalahari.                  | collapsing fabric.                           |
|           |-------------|-----------|----------------------------| Namib sands: single graded and fine with no  |
|           |             | (Qn)      | Sand sea of the Namib.     | CBRs: unsuitable for road layers and asphalt |
|           |             |           | Alluvium,sand,gravel and   | aggregates: See Section 4.6                  |
|           |             |           | pedocretes like calcrete.  | Pedocretes like calcretes: Namibia's natural |
|           |             |           |                            | road building material number one due to     |
|           |             |           |                            | self-stabilising effects: It has been used   |
|           |             |           |                            | with great success for load bearing layers   | |           |             |           |                            | for paved roads and for wearing courses for  |
|           |             |           |                            | unpaved roads: Even sub-standard calcrete    |
|           |             |           |                            | has been proved successful for bearing and   |
|           |             |           |                            | wearing layers: See Section 4.7.             |
|=================================================================================================================|
NOTA: '* ' means " stratigraphy undifferentiated"; 'COMPL' means COMPLEX;
'**' means no specific subgroup or formation has been identified so
far                      

WB00823_.GIF (134 bytes)

[Return to Contents]

forward.GIF (132 bytes)