Abubuwa 5 da ke samar da mai

Mutane da yawa na amfani da mai. A babura da injina da motoci da sauransu, wanda a yanzu komai zai iya tsayawa cik, idan babu mai. Hakan ne ma ya sanya a bara da Shugaba Jonathan Goodluck ya kara kudin mai, al’ummar Najeriya suka rikice, komai ya balgace. Dubi yadda kasashen Yamma suke ta fafutikar […]

Mutane da yawa na amfani da mai. A babura da injina da motoci da sauransu, wanda a yanzu komai zai iya tsayawa cik, idan babu mai. Hakan ne ma ya sanya a bara da Shugaba Jonathan Goodluck ya kara kudin mai, al’ummar Najeriya suka rikice, komai ya balgace. Dubi yadda kasashen Yamma suke ta fafutikar mamaye kasashen da suke da arzikin mai.
Shin mene ne mai? Yaya ake samunsa, kasancewar mutane da yawa suna amfanin da shi ba tare da sanin ko ta yaya aka same shi, har aka hake shi ba? Me ya sa ake samun mai a wani wuri ko kasa, amma kuma ba a samu wani wuri ko kasa?
A wannan mukalar, zan yi gamsasshen bayanin da zai amsa wadannan tambayoyin, ta yadda mai da karatu zai fahimci lamarin.
Abubuwa biyar ke haduwa su samar da mai. Idan aka samu hudu daga cikin biyar din, to ba za a kai ga hakar mai ba.
Da farko ina so a fahimci ana samun mai daga dutse ne. Su duwatsu, a duniya, sun kasu kashi uku ne: Akwai dutsen ‘igneous’ (igniyos) da dutsen ‘sedimentary’ (sedimentare) da kuma dutsen ‘metamorphic’ (metamofik). Ba za a samu mai (a ko’ina) ba, sai a dutsen ‘sedimentary’, sai dai kuma ba wai daga an samu dutsen ‘sedimentary’ za a samu mai ba, a’a, sai idan muhallin ya zama ‘sedimentary basin’ (sedimentari bazin), wato an samu kwayoyin duwatsu da suka zama shimfidu daga dutsen mafari (misali, shale) zuwa dutsen tafki (reserboir rock, misali sandstone) da sauran shimfidun duwatsu.  
Ba lallai ne daga muhalli ya zama ‘sedimentary basin’ kuma ya samar da mai ba, a’a, sai an samu abubuwa biyar a muhallin. Wadannan abubuwa biyar sun hada da: (1) Dutsen mafari (Source Rock) misali, ‘shale’ (shel); sai (2) Dutsen Tafki (Reserboir Rock), misali sandstone (sandsiton); sai (3) Zafi (Geothermal heating -Jotamal hitin); da (4) kaura (Migration -Maigireshin); sai kuma (5) Tarko (Trap).
Bari mu bi su daidai mu ga abin da kowanensu yake nufi:
(1) Dutsen mafari (Source rock)
Shi ne dutse na farko da yake zama matakin samuwar mai. Misalin wannan dutse shi ne ‘shale’. Idan dutsen ‘shale’ na kunshe da sinadaran ‘Hydrocarbons’ (sinadaran da ke kunshe da ‘carbon’) ya zama mafarin dutse. Wasu kan tambaya da yaya ake samun ‘shale’? Akan samu ‘shale’ a lokacin da kwayoyin duwatsu da ake kira ‘sediments’ suka hadu a wuri daya daga karshe kuma sai su dunkule su zama dutsen ‘shale’. An fi samun wannan dutsen a muhallin da ake kira ‘Lacustrine’ (lakostarain) ko ‘Deltaic’ (deltaik), wato muhallin da ya hada da tafki da korama da kududdufi da teku da sahara da sauransu.
Wannan dutse ya karkasu zuwa kashi uku bisa ga bambancin sinadaran ‘hydrocarbons’ da suke kunshe a cikinsa. An kuma yi rabe-raben ne bisa ga sinadarin ‘kerogen’ da sauransu.

1. Dutsen ‘shale’ kan zama dutsen mafari (source rock) ne a lokacin da kwari ko dabbobi da ke rukunin ‘algal’ suka makale a wurin da babu iska sosai (anodic), an kuma fi samun irin wadannan duwatsu a karkashin tafki.
2. Dutsen ‘shale’ kan zama mafarin dutse (source rock) idan kwayoyin bakteriya suka rubar da halittun cikin teku da ake kira ‘planktonic’ a kuma wurin da babu iska, sukan bayar da iskar gas da kuma mai idan akwai zafi, idan kuma suka shige cikin karkashin kasa.
3.       Dutsen ‘shale’ kan zama mafarin dutse idan kwayoyin bakteriya da na ‘fungi’ (fungai) suka rubar da dabbobin tudu kamar su kakan kadangaru (dinosaur) da tsire-tsire a cikin kasa, kuma idan ba su rika samun iska ba. Irin wadanan duwatsu kan samar da kwal da sauransu.
Kafin dutsen ‘shale’ ya zama dutsen mafari, sai idan yana dauke da sinadarin ‘kerogen’ kashi 0.5 a cikinsa, amma kuma yakan zama dutsen mafari mafi kyau idan yana kunshe da kashi 12 zuwa sama a cikinsa. Misalin dutsen ‘shale’ a Najeriya shi ne ‘Fika Shale’.
(2) Dutsen tafki (Reserboir rock)
Shi ne dutse na gaba wanda yake zama ma’ajiyar mai bayan ya yi kaura daga dutsen mafari (source rock). Yana kunshe da kofofi da tarko masu yawa da ke hana man yin kaura bayan ya shiga cikinsa. Misalin wannan dutse shi ne, sandstone, a Najeriya akwai Gombe Sandstone.
(3) Zafi (Geothermal Heating)
Akwai wani zafi da ke taimakawa wurin samuwar mai, shi wannan zafin ake kira ‘geothermal heating’. Zafin da ke samar da mai ya fara daga 60 zuwa 150 a ma’aunin ‘degree centigrade’ (digiri sentigiret), ana auna ma’aunin ‘degree centigrade’ ne bisa ga nisan dutsen a cikin kasa.

Masana binciken kasa sun ce wannan zafin na samuwa ne a karkashin kasa tun lokacin da aka samar da duniya, wanda a yanzu kuma zafin rana da ake kira ‘solar’ (sola) da kuma rubewar sinadarai a cikin kasa ke samar da shi. Zafin da aka samu wurin dutse mai aman wuta da girgizar kasa na taimaka wa zafin da ke samar da mai. Masana sun ce zafi a cikin kasa daga kafa 10 zuwa mita 3 yakan kai 12.8 a ma’aunin ‘degree centigrade’.
(4) kaura (Migration)
kaurar mai na taka muhimmiyar rawa wurin samuwar mai har a kai ga hakarsa. Akwai hanyoyi da yanayi da suke sanya mai ya yi kaura. Akwai kaura ta farko da kuma ta biyu. Ta farko ita ake kira ‘primary migration’ (firamare maigireshin); ta biyu kuma ita ce ‘secondary migration’ (sakandare maigireshin). kaura ta farko takan faru daga dutsen mafari zuwa wani dutsen mafari; kaurar mai ta biyu kuma takan faru daga dutsen mafari zuwa dutsen tafkin mai. Masana sun ce samuwar kwayoyin da suke ba da shimfidu (layers) ta hanyar  bisnewa na haifar da kaurar mai, samuwar bisnewar ake kira ‘burial’ (buriyal).
 Zayyanar shimfidun duwatsu da ke samar da mai. A kasa dutsen mafari ne, sai ruwa da mai a cikin dutsen tafki, a saman dutsen tafki kuma tarko ne (dutsen Rock seal)
Ga yadda kaurar mai ke faruwa daga mashimfidar dutsen mafari (source rock) zuwa dutsen mafari ko zuwan dutsen tafki (Reserboir rock):
Idan zafi ya rika karuwa, zai sanya sinadaran ‘hydrocarbons’ su rika tafasa, kamar yadda ruwa yake tafasa idan aka dora shi a wuta sakamakon zafi. Inda kuma masana suka ce hakan na faruwa a sakamakon bisnewa da ake yi kwayoyin da suka samar da shimfidun duwatsu walau na mafari ko na tafki.
Mu kwana nan.