MAGMA YANA GUDANA DA SAUƘI IDAN AN MATSA SHI — AMMA BA SHI NE DALILIN TARUWARSA BA

Faranti na tectonic na Duniya suna zamewa a kan asthenosphere, wani layi na saman mantle da ke da laushi ba kamar yadda aka saba ba. Wani tsohon ra’ayi shi ne cewa ƙananan adadin dutse mai narkewa — magma na basalt — suna taimakawa wajen sanya shi laushi. Saukin da wannan narkakke ke motsawa a zurfi ya dogara ne da kaurinsa (viscosity). Kuma a nan ne wani baƙon sakamako ya raba masana kimiyyar ƙasa.

Idan ka matsa yawancin abubuwa, sukan ƙara tauri. Duk da haka, gwaje-gwajen matsi mai tsanani, musamman na Sakamaki da abokan aikinsa a 2013, sun ba da rahoton cewa basalt mai narkewa yana zama ƙasa da kauri a ƙarƙashin matsi, har zuwa mafi ƙanƙanta a zurfin kusan kilomita 90 zuwa 150, kafin ya sake ƙara tauri. An yi amfani da wannan ra’ayi don bayyana yadda magma ke motsawa, baƙin alamomin girgizar ƙasa a cikin mantle da sinadarai masu layi-layi. A 2025, Russell da abokan aikinsa sun mayar da martani cewa wannan mafi ƙanƙanta kuskure ne na gwaji, wanda yanayin zafi da ba a sarrafa shi da kyau ya haifar: idan aka gyara, a cewarsu, kauri yana ƙaruwa ne kawai tare da matsi.

Me yasa gwaje-gwaje ke shan wahala

A waɗannan matsi, yana da wuya a raba yanayin zafi da matsi. Ma’aunin zafi a cikin injinan matsi mai tsanani suna da rashin tabbas na kelvin 50 zuwa 100 ko fiye, kuma hanyar gargajiya — auna lokacin da ƙaramar ƙwallo ke ɗauka tana faɗuwa cikin narkakke — bangon ƙananan kwantena masu girman milimita suna damun ta. Tasirin da ake nema ƙarami ne; hayaniyar ba ƙarama ba ce.

Biliyoyin matakai na atom

Hongkun Zeng, Liang Yuan da abokan aikinsu a Jami’ar Kimiyyar Ƙasa ta Sin da ke Wuhan, Jami’ar Bayreuth da Jami’ar Sichuan sun koma ga kwaikwayo. Sun yi samfurin basalt mai sauƙi (cakuɗen ma’adinan diopside da anorthite) atom bayan atom, da ƙarfin da aka lissafa daga injiniyoyin quantum (quantum mechanics) kuma wata hanyar sadarwa ta jijiyoyi (neural network) ke kwaikwaya, wanda ke ba kwaikwayon damar gudana fiye da sau 1,000 fiye da hanyoyin quantum na yau da kullum.

Mabuɗin shi ne ƙididdiga. Ga kowane matsi da yanayin zafi sun gudanar da kwaikwayo masu zaman kansu 150 zuwa 600 na nanosecond 5 kowanne, jimilla aƙalla microsecond 7.5 ga kowace hanya, bayan sun tabbatar cewa hanyarsu tana sake samar da auna yawan ma’adinai na gaske cikin kashi 1%. Hakan ya rage rashin tabbas kan kauri zuwa kashi 1 zuwa 3%, idan aka kwatanta da har zuwa 50% a binciken da suka gabata.

U mara zurfi

A tsayayyen zafi na kelvin 2,073, kauri yana zana U mai laushi: pascal-second 0.108 a matsi sifili, mafi ƙanƙanta na 0.088 a gigapascal 3, sannan 0.104 a gigapascal 6 — raguwar kusan 19%.

A kan layin narkewa, kamar a cikin gwaje-gwaje, kauri maimakon haka yana faɗuwa da ninki kusan 23 tsakanin gigapascal 0 da 6 — amma wannan galibi tasirin hauhawar zafi ne. A matsi sifili, sanyaya daga kelvin 2,073 zuwa 1,619 yana ninka kauri da kusan 18. Kuskuren gwaji na yau da kullum na kelvin 100 don haka yana sauya kauri da fiye da ninki ashirin na girman U ɗin. Ba abin mamaki ba ne da ya yi wuyar gani.

Dalilin yana cikin tsarin atom. Silicon galibi yana kulle cikin ƙungiyoyi masu tauri na oxygen huɗu. Aluminium, akasin haka, yana sake tsarawa sosai a ƙarƙashin matsi — ƙungiyoyinsa na oxygen biyar suna tashi daga kusan 20% zuwa 50% na jimilla — kuma waɗannan wuraren aluminium da ba safai ba, masu saurin canzawa, suna dacewa da lokacin da narkakken ke ɗauka don ya huta. Su ne, ba tsarin silicon ba, ke saita saurin gudanar.

Zafi, ba raguwar ba

Ƙungiyar sai ta yi samfurin yadda narkakke ke ratsawa zuwa sama ta cikin mantle. Saukin motsinsa yana ƙaruwa da zurfi, ya kai ƙololuwa kusa da kilomita 150, kuma yana faɗuwa yayin da narkakken ke hawa yana sanyaya, don haka magma yana son tsayawa da taruwa daidai ƙarƙashin farantin mai tauri — wanda ya yi daidai da alamomin girgizar ƙasa da na lantarki na wani layi mai cike da narkakke a zurfin kilomita 45 zuwa 70.

Amma marubutan sun nanata wani ɗan bambanci da taƙaitaccen bayaninsu (abstract) ya rage muhimmancinsa: wannan ƙololuwar motsi ta samo asali ne daga gasar tsakanin matsi da zafi a kan bayanin yanayin zafi na Duniya, ba daga mafi ƙanƙantar gigapascal 3 ba. Mafi ƙanƙantar kauri gaskiya ne, sun kammala, amma “ba dole ba ne kuma bai isa ba” don bayyana taruwar narkakke; zafi kaɗai yana yin aikin. Basalt ɗinsu mai sauƙi ne — babu ƙarfe, babu sodium, ruwa ne kaɗai abu mai saurin tashi (volatile) — kuma wurin mafi ƙanƙantar ya dogara da haɗin sinadarai.