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Izithethe zobumba zibonisa isakhelo sentlalo-ntle yenkcubeko yangaphambili, ngelixa ukusasazwa kwendawo yobumba kubonisa iipatheni zonxibelelwano kunye neenkqubo zokusebenzisana. Izixhobo kunye ne-geosciences zisetyenziswa apha ukumisela ukufumaneka, ukukhethwa kunye nokucubungula izinto eziluhlaza. Ubukumkani baseCongo, obudume kwihlabathi liphela ukususela ekupheleni kwenkulungwane yeshumi elinesihlanu, lelinye lamazwe adumileyo angaphambili e-Afrika eseMbindini. Nangona uphando oluninzi lwembali luxhomekeke kwiingxelo zomlomo nezibhaliweyo zaseAfrika nezaseYurophu, kusekho izikhewu ezinkulu ekuqondeni kwethu ngoku le yunithi yezopolitiko. Apha sinika ulwazi olutsha malunga nokuveliswa kunye nokusasazwa kobumba eBukumkanini baseCongo. Sisebenzisa iindlela ezininzi zohlalutyo kwiisampuli ezikhethiweyo, ezizezi: i-XRD, i-TGA, uhlalutyo lwe-petrographic, i-XRF, i-VP-SEM-EDS kunye ne-ICP-MS, simisele iimpawu zazo ze-petrographic, i-mineralogical kunye ne-geochemical. Iziphumo zethu zisivumela ukuba sidibanise izinto zakudala kunye nezinto zendalo kwaye simise amasiko e-ceramic. Sichonge iitemplate zemveliso, iipatheni zokutshintshiselana, ukusasazwa kunye neenkqubo zokusebenzisana kweempahla ezisemgangathweni ngokusasazwa kolwazi lobuchwephesha. Iziphumo zethu zibonisa ukuba ukugxila kwezopolitiko kummandla weLower Congo kwi-Central Africa kunempembelelo ethe ngqo kwimveliso kunye nokusasazwa kobumba. Thina Ndiyathemba ukuba uphando lwethu luya kubonelela ngesiseko esihle sezifundo ezithelekisayo ukuze kufumaneke imeko yale ndawo.
Ukwenziwa nokusetyenziswa kwezinto zobumba kube ngumsebenzi ophambili kwiinkcubeko ezininzi, kwaye imeko yalo yezentlalo nezopolitiko ibe nefuthe elikhulu ekucwangcisweni kwemveliso kunye nenkqubo yokwenza ezi zinto1,2.Ngaphakathi kwesi sikhokelo, uphando lwe-ceramic lunokuphucula ukuqonda kwethu uluntu lwangaphambili3,4.Ngokuhlola ii-ceramics zakudala, sinokudibanisa iipropati zazo nezithethe ezithile ze-ceramic kunye neepateni ezilandelayo zemveliso1,4,5.Njengoko kubonisiwe nguMatson6, ngokusekelwe kwi-ecology ye-ceramic, ukhetho lwezinto eziluhlaza lunxulumene nokufumaneka kwendawo kwezixhobo zendalo.Ngaphezu koko, xa kujongwa izifundo ezahlukeneyo ze-ethnographic, iWhitbread2 ibhekisa kumathuba angama-84% ophuhliso lwezixhobo ngaphakathi kwe-7km radius yemvelaphi ye-ceramic, xa kuthelekiswa namathuba angama-80% ngaphakathi kwe-3km radius e-Afrika7.Nangona kunjalo, kubalulekile ukungawujongi ukuxhomekeka kwemibutho yemveliso kwizinto zobugcisa2,3.Ukhetho lwetekhnoloji lungaphandwa ngokuphanda ubudlelwane phakathi kwezixhobo, iindlela kunye nolwazi lwetekhnoloji3,8,9.Uluhlu lweendlela ezinjalo lunokuchaza isithethe esithile se-ceramic.Ngeli xesha, ukuhlanganiswa kwezinto zakudala kuphando kube negalelo kakhulu ekuqondeni ngcono uluntu lwangaphambili3,10,11,12. Ukusetyenziswa kweendlela ezininzi zokuhlalutya kunokuphendula imibuzo malunga nazo zonke izigaba ezibandakanyekayo kwimisebenzi yechungechunge, njengophuhliso lwezixhobo zendalo kunye nokukhethwa kwezinto eziluhlaza, ukuthengwa kunye nokucutshungulwa3,10,11,12.
Olu phononongo lugxile kuBukumkani baseCongo, enye yezona nkqubo zinempembelelo enkulu ekwakhiweni kwazo eCentral Africa. Ngaphambi kokuba kufike ilizwe lanamhlanje, iCentral Africa yayine-mosaic entsonkothileyo yezentlalo-nezopolitiko ebonakala ngokwahluka okukhulu kwenkcubeko nezopolitiko, kunye nezakhiwo eziqala kwiindawo ezincinci neziqhekekileyo zezopolitiko ukuya kwiindawo ezinzima nezigxile kakhulu kwezopolitiko13,14,15. Kule meko yentlalo-nezopolitiko, uBukumkani baseCongo kucingelwa ukuba basekwa kwinkulungwane ye-14 ziindibano ezintathu ezidibeneyo 16, 17. Ngexesha labo lokuphumelela, babugubungela indawo elingana nendawo ephakathi koLwandlekazi lweAtlantiki entshona yeDemocratic Republic of Congo (DRC) yanamhlanje kunye noMlambo iCuango empuma, kunye nendawo yomntla weAngola namhlanje. Ububanzi beLuanda. Badlale indima ebalulekileyo kummandla obanzi ngexesha labo lokuphumelela kwaye banamava ophuhliso oluya kubunzima obukhulu kunye nolawulo oluphakathi ukuya kwi-14, 18, 19, 20, 21 yenkulungwane yeshumi elinesibhozo. Ukwahlulwahlulwa kwezentlalo, imali efanayo, irhafu iinkqubo, ukwabiwa kwabasebenzi abathile, kunye norhwebo lwamakhoboka18, 19 zibonisa imodeli ka-Earle yoqoqosho lwezopolitiko22.Ukususela ekusekweni kwayo ukuya ekupheleni kwenkulungwane ye-17, uBukumkani baseCongo banda kakhulu, kwaye ukususela ngo-1483 ukuya phambili baseka ubudlelwane obuqinileyo neYurophu, kwaye ngale ndlela bathatha inxaxheba kurhwebo lwase-Atlantic 18, 19, 20, 23, 24, 25 (inkcukacha engaphezulu Jonga iSihlomelo 1) ukuze ufumane ulwazi lwembali.
Iindlela zezinto kunye nesayensi ye-geoscience zisetyenzisiwe kwizinto zakudala ezenziwe ngodongwe ezivela kwiindawo ezintathu zakudala eBukumkanini baseCongo, apho kuye kwenziwa khona uphando kwiminyaka elishumi edlulileyo, oluthi yiMbanza Kongo e-Angola kunye neKindoki kunye neNgongo Mbata kwiDemocratic Republic of Congo (Umzobo 1) (jonga iTheyibhile eyoNgezelelweyo 1). 2 kwidatha yezinto zakudala). IMbanza Congo, esandula ukuqoshwa kuLuhlu lweLifa leMveli le-UNESCO, ikwiphondo laseMpemba lolawulo lwamandulo. Ikwindawo ephakathi kwindawo edibana kuyo iindlela zorhwebo ezibalulekileyo, yayilikomkhulu lezopolitiko nelolawulo lobukumkani kunye nesihlalo setrone yokumkani. IKindoki kunye neNgongo Mbata zikwiphondo laseNsundi naseMbata, ngokwahlukeneyo, ezinokuba yinxalenye yezikumkani ezisixhenxe zaseKongo dia Nlaza ngaphambi kokuba ubukumkani busekwe - enye yezopolitiko ezidibeneyo28,29. Zombini zadlala indima ebalulekileyo kwimbali yobukumkani17. Iindawo zakudala zaseKindoki naseNgongo Mbata zikwiNtlambo yase-Inkisi kwinxalenye esemantla yobukumkani kwaye yayiyenye yeendawo zokuqala ezoyiswa ngooyise abasungula ubukumkani.IMbanza Nsundi, ikomkhulu lephondo elinamanxuwa aseJindoki, ngokwesiko belilawulwa ngabalandeli bookumkani baseCongo abalandelayo 17, 18, 30. Iphondo laseMbata likwi-31 empuma ye UMlambo i-Inkisi. Abalawuli baseMbata (kwaye ukuya kuthi ga kwinqanaba elithile eSoyo) banelungelo lembali lokuba ngabona bodwa abakhethwa kwiindwalutho zasekuhlaleni ngokulandelana, kungekhona kwamanye amaphondo apho abalawuli bamiselwa lusapho lwasebukhosini, oko kuthetha ukuba kukho imali eninzi. Nangona yayingengomzi-mkhulu wephondo laseMbata, uNgongo Mbata wadlala indima ephambili ubuncinane kwinkulungwane ye-17. Ngenxa yesikhundla sayo esibalulekileyo kuthungelwano lorhwebo, uNgongo Mbata unegalelo kuphuhliso lwephondo njengemarike ebalulekileyo yorhwebo16,17,18,26,31,32.
UBukumkani baseCongo kunye namaphondo ayo amathandathu aphambili (iMpemba, iNsondi, iMbata, iSoyo, iMbamba, iMpangu) kwinkulungwane yeshumi elinesithandathu neyeshumi elinesixhenxe. Iindawo ezintathu ekuxoxwe ngazo kolu phando (iMbanza Kongo, iKindoki kunye neNgongo Mbata) ziboniswe kwimephu.
Kude kube yiminyaka elishumi eyadlulayo, ulwazi lwezinto zakudala ngoBukumkani baseCongo lwalulinganiselwe. Uninzi lweenkcukacha ngembali yobukumkani lusekelwe kwizithethe zomlomo zasekuhlaleni kunye nemithombo ebhaliweyo evela eAfrika naseYurophu. 16,17. Ulandelelwano lweziganeko kummandla waseCongo luqhekekile kwaye aluphelelanga ngenxa yokunqongophala kwezifundo zezinto zakudala ezicwangcisiweyo. Ukumbiwa kwezinto zakudala ukusukela ngo-2011 kujolise ekuzaliseni ezi zikhewu kwaye kufumanise izakhiwo ezibalulekileyo, iimpawu kunye nezinto zakudala. Kwezi zinto zifunyenweyo, ngokungathandabuzekiyo iimbiza zeplastiki zezona zibalulekileyo. 29, 30, 31, 32, 35, 36. Ngokuphathelele iXesha leSinyithi kuMbindi Afrika, iiprojekthi zezinto zakudala ezifana nezangoku zinqabile kakhulu.
Sibonisa iziphumo zohlalutyo lwe-mineralogy, i-geochemical kunye ne-petrological lweseti yeziqwenga zebumba ezivela kwiindawo ezintathu ezifunyenweyo zoBukumkani baseCongo (jonga idatha yezinto zakudala kwi-Supplementary Material 2). Iisampulu bezizeentlobo ezine zebumba (Umzobo 2), enye ivela kwiJindoji Formation kwaye ezintathu zivela kwiKing Kong Formation 30, 31, 35. Iqela leKindoki liqala kwixesha loBukumkani bokuqala (inkulungwane ye-14 ukuya phakathi kwenkulungwane ye-15). Kwiindawo ekuxoxwe ngazo kolu phononongo, iKindoki (n = 31) yayiyeyona ndawo kuphela eyayibonisa ukuhlanganiswa kweqela leKindoki30,35. Iintlobo ezintathu zamaqela aseKongo - Uhlobo A, Uhlobo C, kunye noHlobo D - ziqala kubukumkani bamva (inkulungwane ye-16-18) kwaye zikhona ngaxeshanye kwiindawo ezintathu zezinto zakudala eziqwalaselwe apha30, 31, 35. Iimbiza zoHlobo C zaseKongo ziimbiza zokupheka ezininzi kuzo zonke iindawo ezintathu35. Ipani yohlobo lweKongo A ingasetyenziswa njengepani yokuphakela, emelwe ziziqwenga ezimbalwa kuphela30, 31, 35. Iiseramikhi zohlobo lweKongo D mazisetyenziswe kuphela ekhaya - njengoko zingazange zifunyanwe kwiindawo zokungcwaba ukuza kuthi ga ngoku - kwaye zinxulunyaniswa neqela elithile labasebenzisi abakhethekileyo 30,31,35. Iziqwenga zazo nazo zibonakala ngamanani amancinci kuphela. Iimbiza zohlobo A no-D zibonise ukusasazwa okufanayo kwendawo kwiindawo zaseKindoki naseNgongo Mbata 30,31. KwiNgongo Mbata, ukuza kuthi ga ngoku, kukho iziqwenga zohlobo C lweKongo ezingama-37,013, apho kukho iziqwenga zohlobo A zeKongo ezili-193 kuphela kunye neziqwenga zohlobo D31 zeKongo ezili-168.
Imifanekiso yeentlobo ezine zamaqela eembiza zaseCongo Kingdom ekuxoxwe ngazo kolu phononongo (iKindoki Group kunye neKongo Group: Iintlobo A, C, kunye no-D); umzobo wembonakalo yazo ngokwexesha kwindawo nganye yezinto zakudala eMbanza Kongo, Kindoki kunye noNgongo Mbata.
I-X-ray Diffraction (XRD), i-Thermogravimetric Analysis (TGA), i-Petrographic Analysis, i-Variable Pressure Scanning Electron Microscopy ene-Energy Dispersive X-ray Spectroscopy (VP-SEM-EDS), i-X-ray Fluorescence Spectroscopy (XRF) kunye ne-Inductively Coupled Plasma Coupled mass spectrometry (ICP-MS) zisetyenzisiwe ukuphendula imibuzo malunga nemithombo enokubakho yezinto ezikrwada kunye neendlela zokuvelisa. Injongo yethu kukuchonga amasiko e-ceramic kwaye siwadibanise neendlela ezithile zokuvelisa, ngaloo ndlela sibonelela ngembono entsha malunga nesakhiwo sentlalo sesinye sezona mibutho zibalaseleyo kwezopolitiko kuMbindi Afrika.
Imeko yoBukumkani baseCongo inzima kakhulu kwizifundo zemithombo ngenxa yokwahluka kunye nokucaciswa komboniso wejoloji yendawo (Umzobo 3). Ijoloji yengingqi inokubonwa ngokubakho kwe-sedimentary geological sedimentary kunye ne-metamorphic sequences ezibizwa ngokuba yiWestern Congo Supergroup. Kwindlela esezantsi ukuya phezulu, ulandelelwano luqala ngokutshintshana ngokwesigqi kwe-quartzite-claystone kwiSansikwa Formation, kulandele iHaut Shiloango Formation, ebonakaliswa bubukho be-stromatolite carbonates, kwaye kwiDemocratic Republic of Congo, iiseli zomhlaba ze-silica Diatomaceous zachongwa kufutshane nezantsi naphezulu kweqela. Iqela le-Neoproterozoic Schisto-Calcaire liqoqo le-carbonate-argillite elinemineralization ethile ye-Cu-Pb-Zn. Olu lwakhiwo lwejoloji lubonisa inkqubo engaqhelekanga ngokusebenzisa i-diagenesis ebuthathaka yodongwe lwe-magnesia okanye utshintsho oluncinci lwe-dolomite evelisa i-talc. Oku kubangela ukuba kubekho imithombo ye-calcium kunye ne-talc mineral. Iyunithi igutyungelwe yiPrecambrian Schisto-Greseux Group equka iibhedi ezibomvu ezinesanti-argillaceous.
Imephu yeJografi yendawo efundwayo. Iindawo ezintathu zezinto zakudala ziboniswe kwimephu (iMbanza Congo, iJindoki kunye neNgongombata). Isangqa esijikeleze indawo simele i-radius ye-7 km, ehambelana nethuba lokusetyenziswa komthombo le-84%2. Imephu ibhekisa kwiDemocratic Republic of the Congo kunye ne-Angola, kwaye imida iphawulwe. Iimephu zeJografi (iifayile zesimo kwiSongezo 11) zenziwe kwisoftware ye-ArcGIS Pro 2.9.1 (iwebhusayithi: https://www.arcgis.com/), ebhekisa kwi-Angolan41 kunye neCongo42,65 Iimephu zeJografi (iifayile ze-raster), kusetyenziswa imigangatho eyahlukeneyo yokuzoba.
Ngaphezulu kokungaqhubeki kwe-sedimentary, iiyunithi zeCretaceous zenziwe ngamatye e-sedimentary e-continental afana ne-sandstone kunye ne-claystone. Kufutshane, olu lwakhiwo lwe-geological lwaziwa njengomthombo wesibini wedayimani emva kokukhukuliseka yi-Early Cretaceous kimberlite tubes41,42. Akukho matye e-igneous kunye ne-high-grade metamorphic axeliweyo kule ndawo.
Indawo ejikeleze iMbanza Kongo ibonakaliswa bubukho beendawo ezidityanisiweyo kunye neekhemikhali kwi-Precambrian strata, ikakhulu i-limestone kunye ne-dolomite ezivela kwi-Schisto-Calcaire Formation kunye ne-slate, i-quartzite kunye ne-ashwag ezivela kwi-Haut Shiloango Formation41. Iyunithi yejoloji ekufutshane nendawo ye-archaeological yaseJindoji yi-Holocene alluvial sedimentary rock kunye ne-limestone, i-slate kunye ne-chert egqunywe yi-feldspar quartzite ye-Precambrian Schisto-Greseux Group. I-Ngongo Mbata ikwi-Schisto-Greseux rock belt encinci phakathi kwe-Schisto-Calcaire Group endala kunye ne-Cretaceous red sandstone ekufutshane42. Ukongeza, umthombo weKimberlite obizwa ngokuba yiKimpangu uxelwe kufutshane neNgongo Mbata kufutshane ne-craton kummandla weLower Congo.
Iziphumo zesiqingatha-ubungakanani zezigaba eziphambili zeeminerali ezifunyenwe yi-XRD ziboniswe kwiTheyibhile 1, kwaye iipateni ze-XRD ezimeleyo ziboniswe kwiFigure 4. IQuartz (SiO2) sisigaba esiphambili seminerali, esinxulunyaniswa rhoqo ne-potassium feldspar (KAlSi3O8) kunye ne-mica.[Umzekelo, i-KAl2(Si3Al)O12(OH)2], kunye/okanye i-talc [Mg3Si4O10(OH)2]. Iiminerali ze-plagioclase [XAl(1–2)Si(3–2)O8, X = Na okanye i-Ca] (oko kukuthi i-sodium kunye/okanye i-anorthite) kunye ne-amphibole [(X)(0–3)[(Z )(5– 7)(Si, Al)8O22(O,OH,F)2, X = Ca2+, Na+, K+, Z = Mg2+, Fe2+, Fe3+, Mn2+, Al, Ti] ziizigaba zekristale ezinxulumeneyo, Ngokwesiqhelo kukho i-mica. I-Amphibole idla ngokungabikho kwi i-talc.
Iipateni ze-XRD ezimeleyo ze-pottery yaseKongo Kingdom, ezisekelwe kwizigaba ezinkulu zekristale, ezihambelana namaqela ohlobo: (i) izinto ezityebileyo ze-talc ezifunyenwe kwiisampulu zeKindoki Group kunye neKongo Type C, (ii) i-talc etyebileyo efunyenwe kwiisampulu izinto eziqulethe iQuartz iisampulu zeKindoki Group kunye neKongo Type C, (iii) izinto ezityebileyo ze-feldspar kwiisampulu zeKongo Type A kunye neKongo D, (iv) izinto ezityebileyo ze-mica kwiisampulu zeKongo Type A kunye neKongo D, (v) Izinto ezityebileyo ze-Amphibole zifunyenwe kwiisampulu ezivela kwiKongo Type A kunye neKongo Type DQ quartz, Pl plagioclase, okanye i-potassium feldspar, Am amphibole, Mca mica, Tlc talc, Vrm vermiculite.
Iispectra ze-XRD ezingaziwayo ze-talc Mg3Si4O10(OH)2 kunye ne-pyrophyllite Al2Si4O10(OH)2 zifuna indlela eyongezelelekileyo yokuchonga ubukho bazo, ukungabikho kwazo okanye ukubakho kwazo. I-TGA yenziwe kwiisampuli ezintathu ezimeleyo (MBK_S.14, KDK_S.13 kunye ne-KDK_S.20). Ii-TG curves (i-Supplement 3) zazihambelana nobukho besigaba se-talc mineral kunye nokungabikho kwe-pyrophyllite. I-dehydroxylation kunye nokubola kwesakhiwo okubonwe phakathi kwe-850 kunye ne-1000 °C kuhambelana ne-talc. Akukho lahleko yobunzima ebonwe phakathi kwe-650 kunye ne-850 °C, ebonisa ukungabikho kwe-pyrophyllite44.
Njengesigaba esincinci, i-vermiculite [(Mg, Fe+2, Fe+3)3[(Al, Si)4O10](OH)2 4H2O], echongiweyo ngohlalutyo lwee-aggregates ezijolise kwiisampuli ezimeleyo, incopho Ifumaneka kwi-16-7 Å, ifunyenwe kakhulu kwiisampuli zeKindoki Group kunye neKongo Group Type A.
Iisampulu zohlobo lweKindoki Group ezifunyenwe kwindawo ebanzi ejikeleze iKindoki zibonise umxube weeminerali obonakala ngokubakho kwe-talc, ubuninzi be-quartz kunye ne-mica, kunye nokubakho kwe-potassium feldspar.
Ukwakheka kwezimbiwa zeesampuli zohlobo lwe-Kongo kuphawulwa bubukho benani elikhulu leeperi ze-quartz-mica ngobuninzi obahlukeneyo kunye nobukho be-potassium feldspar, i-plagioclase, i-amphibole, kunye ne-mica. Ubuninzi be-amphibole kunye ne-feldspar buphawula olu hlobo lweqela, ngakumbi kwiisampuli zohlobo lwe-Congo eJindoki naseNgongombata.
Iisampulu zohlobo C lwaseKongo zibonisa umxube weeminerali ezahlukeneyo kwiqela lohlobo, oluxhomekeke kakhulu kwindawo yezinto zakudala. Iisampulu ezivela kwiNgongo Mbata zityebile kwi-quartz kwaye zibonisa umxube ohambelanayo. I-Quartz ikwalinqanaba eliphambili kwiisampulu zohlobo C lwaseKongo ezivela kwiMbanza Kongo naseKindoki, kodwa kwezi meko ezinye iisampulu zityebile kwi-talc nakwi-mica.
Uhlobo lweKongo D lunesakhiwo esahlukileyo seminerali kuzo zonke iindawo ezintathu zakudala. IFeldspar, ingakumbi iplagioclase, ininzi kolu hlobo lwezitya zodongwe. I-Amphibole idla ngokubakho ngobuninzi. Imele i-quartz kunye ne-mica. Ubungakanani obuhambelanayo buyahluka phakathi kweesampuli. I-Talc ifunyenwe kwiziqwenga ze-amphibole ezityebileyo zeqela le-Mbanza Kongo.
Iiminerali eziphambili eziqinisiweyo ezichongiweyo ngohlalutyo lwe-petrographic yi-quartz, i-feldspar, i-mica kunye ne-amphibole. Ukufakwa kwamatye kuqulathe iziqwenga zamatye aphakathi naphezulu aguquguqukayo, angenawo umbane kunye namatye amdaka. Idatha yelaphu efunyenwe kusetyenziswa itshathi yesalathiso se-Orton45 ibonisa ukubekwa kwesimo ukusuka kokubi ukuya kokulungileyo, kunye nomlinganiselo we-matrix yesimo ukusuka kwi-5% ukuya kwi-50%. Iinkozo eziqinisiweyo ziqala kwi-round ukuya kwi-angular ngaphandle kokukhetha.
Amaqela amahlanu e-lithofacies (i-PGa, i-PGb, i-PGc, i-PGd, kunye ne-PGe) ahlulwe ngokusekwe kutshintsho lwesakhiwo kunye nolwe-mineralogical. Iqela le-PGa: i-low-specific tempered matrix (5-10%), i-fine matrix, kunye nee-inclusions ezinkulu zamatye e-sedimentary metamorphic (Umzobo 5a); Iqela le-PGb: umlinganiselo ophezulu we-tempered matrix (20%-30%), i-tempered matrix. Ukuhlela umlilo kuphantsi, iinkozo ezithambileyo ziyi-angular, kwaye amatye e-metamorphic aphakathi naphezulu anomxholo ophezulu we-layered silicate, i-mica kunye ne-large rock inclusions (Umzobo 5b); Iqela le-PGc: umlinganiselo ophezulu we-tempered matrix (20-40%), ukuhlela umoya olungileyo ukuya kolungileyo kakhulu, iinkozo ezijikelezayo ezincinci ukuya kwezincinci kakhulu, iinkozo ze-quartz ezininzi, ii-planar voids ezithile (c kumzobo 5); Iqela le-PGd: umlinganiselo ophantsi I-Tempered matrix (5-20​​​​%), kunye neenkozo ezincinci ezithambileyo, ii-inclusions zamatye amakhulu, ukuhlela okubi, kunye ne-fine matrix texture (d kumzobo 5); kunye neqela le-PGe: umlinganiselo ophezulu we-tempered matrix (40-50%), ukuhlelwa kobushushu okuhle ukuya kokulungileyo kakhulu, ubungakanani obubini beenkozo ezithambileyo kunye neendidi ezahlukeneyo zeeminerali ngokwe-tempering (Umzobo 5, e). Umfanekiso 5 ubonisa i-optical micrograph emele iqela le-petrographic. Izifundo ze-optical zeesampulu zikhokelele kulwalamano oluqinileyo phakathi kokuhlelwa kohlobo kunye neeseti ze-petrographic, ngakumbi kwiisampulu ezivela kuKindoki kunye noNgongo Mbata (jonga i-Supplementary 4 ukuze ufumane ii-photomicrographs ezimele iseti yonke yesampulu).
Ii-micrographs ezimele i-optical zezilayi ze-pottery zaseKongo Kingdom; ukungqinelana phakathi kwamaqela e-petrographic kunye namaqela e-typological.(a) Iqela le-PGa, (b) Iqela le-PGB, (c) Iqela le-PGc, (d) Iqela le-PGd kunye (e) neqela le-PGe.
Isampulu yeKindoki Formation ibandakanya ukwakheka kwamatye okuchazwe kakuhle okunxulumene nokwakheka kwePGa. Iisampulu zohlobo lweKongo A zinxulumene kakhulu nee-lithofacies zePGb, ngaphandle kwesampulu yohlobo lweKongo A iNBC_S.4 Kongo-A evela kwiNgongo Mbata, enxulumene neqela lePGe ngokweendidi. Uninzi lweesampulu zohlobo lweKongo C ezivela kwiKindoki kunye neNgongo Mbata, kunye neesampulu zohlobo lweKongo C iMBK_S.21 kunye neMBK_S.23 ezivela kwiMbanza Kongo bezizezeqela lePGc. Nangona kunjalo, iisampulu ezininzi zohlobo lweKongo C zibonisa iimpawu zezinye ii-lithofacies. Iisampulu zohlobo lweKongo C iMBK_S.17 kunye neNBC_S.13 zibonisa iimpawu zokuthungwa ezinxulumene namaqela ePGe. Iisampulu zohlobo lweKongo C iMBK_S.3, MBK_S.12 kunye neMBK_S.14 zenza iqela elinye le-lithofacies iPGd, ngelixa iisampulu zohlobo lweKongo C iKDK_S.19, KDK_S.20 kunye neKDK_S.25 zineempawu ezifanayo neqela le-PGb. Isampulu yohlobo lweKongo C i-MBK_S.14 ingathathwa njengengaphandle ngenxa yobume bayo obunemingxuma. Phantse zonke iisampulu ezikwihlobo lweKongo D zinxulunyaniswa nee-PGe lithofacies, ngaphandle kwesampulu zohlobo lweKongo D i-MBK_S.7 kunye ne-MBK_S.15 ezivela eMbanza Kongo, ezibonisa iinkozo ezinkulu ezifudumeleyo ezinobunzima obuphantsi (30%), kufutshane neqela le-PGc.
Iisampulu ezivela kwiindawo ezintathu zakudala zihlalutywe yi-VP-SEM-EDS ukubonisa ukusasazwa kwezinto ezisisiseko kunye nokuchonga ukwakheka kwezinto ezisisiseko kwiinkozo eziqinisiweyo zomntu ngamnye. Idatha ye-EDS ivumela ukuchongwa kwe-quartz, i-feldspar, i-amphibole, ii-iron oxides (i-hematite), ii-titanium oxides (umz. i-rutile), ii-titanium iron oxides (i-ilmenite), ii-zirconium silicates (i-zircon) kunye nee-perovskite neosilicates (i-garnet). I-Silica, i-aluminium, i-potassium, i-calcium, i-sodium, i-titanium, i-iron kunye ne-magnesium zezona zinto zixhaphakileyo zeekhemikhali kwi-matrix. Umxholo ophezulu we-magnesium rhoqo kwi-Kindoki Formation kunye ne-Kongo A-type basin unokuchazwa bubukho beeminerali zodongwe ze-talc okanye ze-magnesium. Ngokohlalutyo lwezinto ezisisiseko, iinkozo ze-feldspar zihambelana kakhulu ne-potassium feldspar, i-albite, i-oligoclase, kwaye ngamanye amaxesha i-labradorite kunye ne-anorthite (Isongezelelo 5, Umfanekiso S8–S10), ngelixa iinkozo ze-amphibole ziyi-tremolite Stone, i-actinite, kwimeko ye-Kongo Type A. isampulu ye-NBC_S.3, ilitye elibomvu. Umahluko ocacileyo uyabonakala kwindlela ekwakhiwe ngayo i-amphibole (Umzobo 6) kwi-Kongo A-type (tremolite) kunye ne-Kongo D-type ceramics (actinite). Ngaphezu koko, kwiindawo ezintathu zakudala, iinkozo ze-ilmenite zazinxulunyaniswa ngokusondeleyo neesampulu ze-D-type. Umxholo ophezulu we-manganese ufumaneka kwiinkozo ze-ilmenite. Nangona kunjalo, oku akuzange kutshintshe indlela yabo yokutshintsha i-iron-titanium (Fe-Ti) eqhelekileyo (jonga i-Supplementary 5, Umfanekiso S11).
Idatha ye-VP-SEM-EDS. Umzobo we-ternary obonisa ukwakheka okwahlukileyo kwe-amphibole phakathi kweetanki zeKongo Type A kunye neKongo D kwiisampuli ezikhethiweyo kwiMbanza Kongo (MBK), Kindoki (KDK), kunye neNgongo Mbata (NBC); iimpawu ezifakwe kwiifayile ngamaqela ohlobo.
Ngokweziphumo ze-XRD, i-quartz kunye ne-potassium feldspar zezona zimbiwa ziphambili kwiisampuli zohlobo C lwaseKongo, ngelixa ubukho be-quartz, i-potassium feldspar, i-albite, i-anorthite kunye ne-tremolite ziimpawu zeesampuli zohlobo A lwaseKongo. Iisampuli zohlobo D lwaseKongo zibonisa ukuba i-quartz, i-potassium feldspar, i-albite, i-oligofeldspar, i-ilmenite kunye ne-actinite zezona zimbiwa ziphambili. Isampulu yohlobo A lwaseKongo i-NBC_S.3 inokuthathwa njengengaphandle kuba i-plagioclase yayo yi-labradorite, i-amphibole yi-orthopamphibole, kwaye ubukho be-ilmenite burekhodwe. Isampulu yohlobo C lwaseKongo i-NBC_S.14 ikwanazo neenkozo ze-ilmenite (Isongezelelo sesi-5, Imifanekiso S12–S15).
Uhlalutyo lwe-XRF lwenziwe kwiisampuli ezimeleyo ezivela kwiindawo ezintathu zakudala ukuze kufunyanwe amaqela amakhulu ezinto. Izinto eziphambili ezidityanisiweyo zidweliswe kwiTheyibhile 2. Iisampuli ezihlalutyiweyo ziboniswe ukuba zityebile kwi-silica kunye ne-alumina, kunye noxinzelelo lwe-calcium oxide ngaphantsi kwe-6%. Uxinzelelo oluphezulu lwe-magnesium lubangelwa bubukho be-talc, enxulumene ngokuchaseneyo ne-oxides ye-silicon kunye ne-aluminium oxide. Umxholo ophezulu we-sodium oxide kunye ne-calcium oxide uhambelana nobuninzi be-plagioclase.
Iisampulu zeKindoki Group ezifunyenwe kwindawo yeKindoki zibonise ukutyeba okukhulu kwe-magnesia (8-10%) ngenxa yokubakho kwe-talc. Amanqanaba e-potassium oxide kolu hlobo lweqela aqala kwi-1.5 ukuya kwi-2.5%, kwaye amanqanaba e-sodium (< 0.2%) kunye ne-calcium oxide (< 0.4%) ayephantsi.
Amanqanaba aphezulu ee-iron oxides (7.5–9%) luphawu oluqhelekileyo kwiimbiza zohlobo lwe-Kongo A. Iisampuli zohlobo lwe-Kongo ezivela eMbanza Kongo naseKindoki zibonise amanqanaba aphezulu e-potassium (3.5–4.5%). Umxholo ophezulu we-magnesium oxide (3–5%) wahlula isampuli yeNgongo Mbata kwezinye iisampuli zeqela elifanayo. Isampulu yohlobo lwe-Kongo A NBC_S.4 ibonisa amanqanaba aphezulu kakhulu ee-iron oxides, ezinxulunyaniswa nokuba khona kwezigaba ze-amphibole mineral. Isampulu yohlobo lwe-Kongo A NBC_S.3 ibonise amanqanaba aphezulu e-manganese (1.25%).
I-Silica (60-70%) ilawula ukwakheka kwesampulu yohlobo lwe-Kongo C, ehambelana nomxholo we-quartz omiselwe yi-XRD kunye ne-petrography. Umxholo we-sodium ephantsi (< 0.5%) kunye ne-calcium (0.2–0.6%) ubonwe. Ubuninzi be-magnesium oxide (13.9 kunye ne-20.7%, ngokulandelanayo) kunye ne-iron oxide ephantsi kwiisampulu ze-MBK_S.14 kunye ne-KDK_S.20 zihambelana neeminerali ezininzi ze-talc. Iisampulu ze-MBK_S.9 kunye ne-KDK_S.19 zolu hlobo zibonise ubuninzi be-silica kunye nomxholo ophezulu we-sodium, i-magnesium, i-calcium kunye ne-Iron oxide. Ubuninzi be-titanium dioxide (1.5%) buhlula isampuli ye-Kongo Type C MBK_S.9.
Umahluko kwimilo yezinto ezisisiseko ubonisa iisampulu zohlobo lweKongo D, ezibonisa umxholo ophantsi we-silica kunye noxinzelelo oluphezulu lwe-sodium (1-5%), i-calcium (1-5%), kunye ne-potassium oxide kuluhlu oluphakathi kwe-44% ukuya kwi-63% (1-5%) ngenxa yokubakho kwe-feldspar. Ngaphezu koko, umxholo ophezulu we-titanium dioxide (1-3.5%) ubonwe kolu hlobo lweqela. Umxholo ophezulu we-iron oxide kwiisampulu zohlobo lweKongo D i-MBK_S.15, i-MBK_S.19 kunye ne-NBC_S.23 unxulunyaniswa nomxholo ophezulu we-magnesium oxide, ohambelana nolawulo lwe-amphibole. Uxinzelelo oluphezulu lwe-manganese oxide lufunyenwe kuzo zonke iisampulu zohlobo lweKongo D.
Idatha yento ephambili ibonise ulwalamano phakathi kwe-calcium kunye ne-iron oxides kwiitanki zohlobo lwe-Kongo A kunye ne-D, ezazinxulunyaniswa nokutyetyiswa kwe-sodium oxide. Ngokuphathelele ukwakheka kwento elandelelanayo (Isongezelelo 6, Itheyibhile S1), uninzi lweesampuli zohlobo lwe-Kongo D zityebile kwi-zirconium enolwalamano oluphakathi ne-strontium. Iploti ye-Rb-Sr (Umzobo 7) ibonisa ulwalamano phakathi kweetanki zohlobo lwe-strontium kunye ne-Kongo D, kunye naphakathi kweetanki zohlobo lwe-rubidium kunye ne-Kongo A. Zombini ii-ceramics zeKindoki Group kunye neKongo Type C ziphelile kuzo zombini izinto. (Jonga kwakhona iSongezelelo 6, Imifanekiso S16-S19).
Idatha ye-XRF. Iploti ye-Scatter Rb-Sr, iisampulu ezikhethwe kwiimbiza zeCongo Kingdom, ezinemibala ngokweqela lohlobo. Igrafu ibonisa unxibelelwano phakathi kwetanki yohlobo lwe-Kongo D kunye ne-strontium kunye naphakathi kwetanki yohlobo lwe-Kongo A kunye ne-rubidium.
Isampulu emeleyo evela eMbanza Kongo ihlalutywe yi-ICP-MS ukuze kuchongwe ukwakheka kwe-trace element kunye ne-trace element, kunye nokufunda ukusasazwa kweepateni ze-REE phakathi kwamaqela ohlobo. I-trace kunye ne-trace elements zichazwe ngokubanzi kwiSihlomelo 7, Itheyibhile S2. Iisampulu zohlobo lweKongo A kunye neesampulu zohlobo lweKongo D MBK_S.7, MBK_S.16, kunye ne-MBK_S.25 zityebile kwi-thorium. Ii-Kongo A-type cans ziqulathe ubuninzi be-zinc kwaye zityebile kwi-rubidium, ngelixa ii-Kongo D-type cans zibonisa ubuninzi be-strontium, okuqinisekisa iziphumo ze-XRF (Isongezelelo 7, Imifanekiso S21–S23). I-La/Yb-Sm/Yb plot ibonisa ulwalamano kwaye ibonisa umxholo ophezulu we-lanthanum kwisampulu ye-Kongo D-tank (Umfanekiso 8).
Idatha ye-ICP-MS. Iploti yokusasaza ye-La/Yb-Sm/Yb, iisampulu ezikhethiweyo ezivela kwiCongo Kingdom basin, ezinemibala ngokweqela lohlobo. Isampulu yohlobo C yaseKongo i-MBK_S.14 ayiboniswanga kumfanekiso.
Ii-REEs ezilungisiweyo yi-NASC47 ziboniswa ngendlela yemigca yesigcawu (Umzobo 9). Iziphumo zibonise ukutyetyiswa kwezinto ezinqabileyo zomhlaba ezikhanyayo (ii-LREE), ingakumbi kwiisampulu ezivela kwiitanki zohlobo lwe-Kongo A kunye nohlobo lwe-D. Uhlobo lwe-Kongo C lubonise umahluko ophezulu. I-positive europium anomaly iluphawu lohlobo lwe-Kongo D, kwaye i-cerium anomaly ephezulu iluphawu lohlobo lwe-Kongo A.
Kolu phononongo, sihlolisise iseti yeeseramikhi ezivela kwiindawo ezintathu zakudala zaseMbindi Afrika ezinxulumene noBukumkani baseCongo ezikumaqela ahlukeneyo ohlobo, oko kukuthi amaqela aseJindoki naseCongo. Iqela laseJinduomu limele ixesha langaphambili (ixesha lobukumkani bokuqala) kwaye likho kuphela kwindawo yezinto zakudala zaseJinduomu. Iqela laseKongo—iintlobo A, C, kunye no-D—likho kwiindawo ezintathu zakudala ngaxeshanye. Imbali yeQela laseKing Kong inokulandelwa emva kwixesha lobukumkani. Limele ixesha lokunxibelelana neYurophu kunye nokutshintshiselana ngeempahla ngaphakathi nangaphandle koBukumkani baseCongo, njengoko bekunjalo kangangeenkulungwane. Iminwe yeminwe edityanisiweyo kunye neyokwakheka kwamatye yafunyanwa kusetyenziswa indlela yokuhlalutya emininzi. Eli lixesha lokuqala iCentral Africa isebenzisa isivumelwano esinjalo.
Iminwe yeKindoki Group ehambelanayo yokwakheka kunye nolwakhiwo lwamatye ibonisa iimveliso ezikhethekileyo zeKindoki. Iqela leKindoki lisenokuba linxulumene nexesha apho iNsondi yayiliphondo elizimeleyo leSeven Congo dia Nlaza28,29. Ubukho betalc kunye nevermiculite (imveliso yobushushu obuphantsi betalc weathering) kwiJinduoji Group bubonisa ukusetyenziswa kwezinto eziluhlaza zasekuhlaleni, njengoko italc ikhona kwi-geological matrix yendawo yeJinduoji, kwiSchisto-Calcaire Formation 39,40. Iimpawu zelaphu zolu hlobo lwembiza ezibonwa luhlalutyo lokuthungwa zibonisa ukucutshungulwa kwezinto eziluhlaza ezingezizo eziphambili.
Iimbiza zohlobo lwe-Kongo A zibonise umahluko othile kwimilo yazo ngaphakathi nangaphandle kwendawo. I-Mbanza Kongo kunye ne-Kindoki ziphezulu kwi-potassium kunye ne-calcium oxides, ngelixa i-Ngongo Mbata iphezulu kwi-magnesium. Nangona kunjalo, ezinye iimpawu eziqhelekileyo ziyahlula kwezinye iindidi. Zihlala zifana kakhulu kwilaphu, ziphawulwe yi-mica paste. Ngokungafaniyo nohlobo lwe-Kongo C, zibonisa umxholo ophezulu we-feldspar, i-amphibole kunye ne-iron oxide. Umxholo ophezulu we-mica kunye nobukho be-tremolite amphibole kuyazahlula kwi-Kongo D-type basin, apho kuchongwa khona i-actinolite amphibole.
Uhlobo C lwaseKongo lukwabonisa utshintsho kwi-mineralogy kunye nokwakheka kweekhemikhali kunye neempawu zelaphu kwiindawo ezintathu zakudala kunye naphakathi kwazo. Olu tshintsho lubangelwa kukuxhaphazwa kwayo nayiphi na imithombo yezinto eziluhlaza ezikhoyo kufutshane nendawo nganye yemveliso/yokusetyenziswa. Nangona kunjalo, ukufana kwesimbo kuye kwafezekiswa ukongeza kwiinguqu zobugcisa zasekuhlaleni.
Uhlobo lweKongo D lunxulumene kakhulu noxinzelelo oluphezulu lwee-titanium oxides, olubangelwa bubukho beeminerali ze-ilmenite (Isongezelelo 6, Umfanekiso S20). Umxholo ophezulu we-manganese weenkozo ze-ilmenite ezihlalutyiweyo uzidibanisa ne-manganese ilmenite (Umfanekiso 10), umxube owahlukileyo ohambelana nokwakheka kwe-kimberlite48,49. Ubukho bamatye e-Cretaceous continental sedimentary—umthombo we-dipozithi zedayimani yesibini emva kokukhukuliseka kweetyhubhu ze-kimberlite zangaphambi kweCretaceous42—kunye nentsimi yeKimberlite exeliweyo yeKimberlite kwiLower Congo43 zibonisa ukuba indawo ebanzi yeNgongo Mbata isenokuba ngumthombo weCongo (DRC) wezinto eziluhlaza zokuvelisa iimbiza zohlobo lwe-D. Oku kuxhaswa ngakumbi kukuchongwa kwe-ilmenite kwisampulu enye yohlobo lweKongo A kunye nesampulu enye yohlobo lweKongo C kwindawo yeNgongo Mbata.
Idatha ye-VP-SEM-EDS. Iploti yokusasaza ye-MgO-MnO, iisampulu ezikhethiweyo ezivela kwi-Mbanza Kongo (MBK), i-Kindoki (KDK) kunye ne-Ngongo Mbata (NBC) kunye neenkozo ze-ilmenite ezichongiweyo, ezibonisa i-ferromanganese ye-manganese-titanium esekelwe kuphando lukaKaminsky noBelousova iMine (Mn-ilmenites).
Iimeko ezingaqhelekanga ze-Europium ezibonwe kwimo ye-REE yetanki yohlobo lwe-Kongo D (jonga uMfanekiso 9), ngakumbi kwiisampuli ezineengqolowa ze-ilmenite ezichongiweyo (umz., MBK_S.4, MBK_S.5, kunye ne-MBK_S.24), mhlawumbi ezinxulunyaniswa namatye e-ultrabasic igneous atyebileyo kwi-anorthite kunye nokugcina i-Eu2+. Olu sasazo lwe-REE lunokuchaza noxinzelelo oluphezulu lwe-strontium olufunyenwe kwiisampuli zohlobo lwe-Kongo D (jonga uMfanekiso 6) kuba i-strontium ithatha indawo ye-calcium50 kwi-lattice yeminerali ye-Ca. Umxholo ophezulu we-lanthanum (Umfanekiso 8) kunye nokutyeba ngokubanzi kwe-LREEs (Umfanekiso 9) kunokubangelwa ngamatye e-ultrabasic igneous njengee-geological formations ezifana ne-kimberlite51.
Iimpawu ezikhethekileyo zokwakheka kweembiza ezimile okwe-D zaseKongo zizidibanisa nomthombo othile wezinto zemvelo, kunye nokufana kokwakheka phakathi kwendawo kolu hlobo, okubonisa iziko lemveliso elahlukileyo leembiza ezimile okwe-D zaseKongo. Ukongeza ekuchazeni kokwakheka, ukusasazwa kobukhulu beesuntswana ezithambileyo zohlobo lwe-D lwaseKongo kubangela izinto zeseramikhi eziqinileyo kwaye kubonisa ukucutshungulwa kwezinto eziluhlaza okwenziwe ngabom kunye nolwazi oluphambili lobuchwephesha ekuvelisweni kweembiza zodongwe52. Olu phawu luhlukile kwaye luxhasa ngakumbi ukutolikwa kolu hlobo njengemveliso ejolise kwiqela elithile labasebenzisi35. Ngokuphathelele olu mveliso, uClist et al29 bacebisa ukuba kusenokwenzeka ukuba lubangelwe kukunxibelelana phakathi kwabenzi beethayile basePortugal kunye nababumbi baseCongo, njengoko olo lwazi lungazange lubonwe ngexesha lobukumkani nangaphambili.
Ukungabikho kwezigaba zeeminerali ezisandula ukwenziwa kwiisampuli ezivela kuzo zonke iintlobo zamaqela kubonisa ukusetyenziswa kobushushu obuphantsi (< 950 °C), nto leyo ehambelana nezifundo ze-ethnoarchaeological ezenziwe kule ndawo53,54. Ukongeza, ukungabikho kwe-hematite kunye nombala omnyama wezinye iziqwenga zebumba kubangelwa kukudubula okunciphileyo okanye emva kokudubula4,55. Izifundo ze-ethnographic kule ndawo zibonise iipropati zokucubungula emva komlilo ngexesha lokwenziwa kweebumba55. Imibala emnyama, efumaneka kakhulu kwiimbiza ezimile okwe-D zaseKongo, inokunxulunyaniswa nabasebenzisi ekujoliswe kubo njengenxalenye yokuhombisa kwabo okutyebileyo. Idatha ye-ethnographic kumxholo obanzi wase-Afrika ixhasa eli bango, njengoko iimbiza ezimnyama zihlala zithathwa njengezinentsingiselo ezithile zomfuziselo.
Uxinzelelo oluphantsi lwe-calcium kwiisampuli, ukungabikho kwee-carbonates kunye/okanye izigaba zazo zezimbiwa ezisandula ukwenziwa zibangelwa yindalo engekho calcium kwiiceramics57. Lo mbuzo unomdla kakhulu kwiisampuli ezityebileyo kwi-talc (ikakhulu iKindoki Group kunye neKongo Type C basin) kuba zombini i-carbonate kunye ne-talc zikhona kwi-local carbonate-argillaceous assemblage-Neoproterozoic Schisto-Calcaire Group42,43 Mutually. Ukufunyanwa ngabom kweentlobo ezithile zezinto ezikrwada ezivela kwi-geological formation efanayo kubonisa ulwazi oluphambili lobuchwephesha olunxulumene nokuziphatha okungafanelekanga kodongwe lwe-calcareous xa lutshiswa kubushushu obuphantsi.
Ukongeza kwiinguqulelo zezakhiwo zeKongo C ngaphakathi nangaphandle kwentsimi kunye nolwakhiwo lwamatye, imfuno ephezulu yokusetyenziswa kwezitya zokupheka isivumele ukuba sibeke imveliso yeKongo C kwinqanaba loluntu. Nangona kunjalo, umxholo we-quartz kwiisampulu ezininzi zohlobo lweKongo C ubonisa ukuhambelana kwemveliso yezixhobo zodongwe ebukumkanini. Ibonisa ukukhethwa ngononophelo kwezinto eziluhlaza kunye nolwazi oluphambili lobuchwephesha olunxulumene nomsebenzi ofanelekileyo nofanelekileyo weQuartz Temper Cooking Pot58. Izinto zokupholisa zeQuartz kunye ne-calcium-free zibonisa ukuba ukukhethwa kunye nokucubungula izinto eziluhlaza kuxhomekeke kwiimfuno zomsebenzi wobugcisa.