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Geology of Indonesian Pumice

Pumice ama pumice waa nooc ka mid ah dhagaxa midabkiisu fudud yahay, waxa ku jira xumbo ka samaysan xumbo- gidaar ah oo quraarado ah, waxaana inta badan loo yaqaannaa galaas foolkaanada silicate ah.

Dhagaxyadan waxa samaysma magma acidic ah oo ay sameeyaan ficilka foolkaanaha oo walxaha hawada ku soo saara; dabadeed mari gaadiidka jiifka ah oo ku urura sidii dhagax pyroclastic ah.

Pumice waxa uu leeyahay sifooyin kala duwan oo aad u sarreeya, waxa uu ka kooban yahay tiro badan oo unugyo ah (qaab-dhismeedka gacanta) sababtoo ah balaadhinta xumbo gaaska dabiiciga ah ee ku dhex jira, waxaana guud ahaan laga helaa walxo dabacsan ama jajabyo ku jira breccia volcano. Halka macdanta ku jirta pumice ay yihiin feldspar, quartz, obsidian, cristobalite, iyo tridymite.

Pumice waxay dhacdaa marka magma acidic ah ay kor u kacdo oo si lama filaan ah ula soo baxdo hawada dibadda. Xumbada dhalooyinka dabiiciga ah ee gaaska ku jira ayaa fursad u leh inay baxsadaan magma-gu si lama filaan ah ayay u barafaysaa, bamgaruhu guud ahaan waxay u jiraan jajabyo la soo saaro inta lagu jiro qarxinta volcano u dhexeeya cabbirka dhagax ilaa dhagaxyo.

Pumice waxay caadi ahaan u dhacdaa sida dhalaalid ama qulqulaya, walxo dabacsan ama jajabyo ku jira breccias foolkaanada.

Pumice waxa kale oo lagu samayn karaa kuleylinta obsidian, si gaasku u baxsado. Kuleylinta lagu sameeyay obsidian ka Krakatoa, heerkulka loo baahan yahay si loogu beddelo obsidian bamka celcelis ahaan 880oC. Cuf-jiidka gaarka ah ee obsidian oo asal ahaan ahaa 2.36 ayaa hoos ugu dhacay 0.416 daawaynta ka dib, sidaa darteed waxa ay sabbaysaa biyaha. Dhagaxan bamka ahi waxa uu leeyahay sifooyin biyo-biyood ah.

Pumice waa cadaan ilaa cawl, huruud ilaa casaan, qaab-dhismeed vesicular leh oo cabbirkiisu le’eg yahay, kaas oo ku kala duwan midba midka kale ama aan ahayn dhismo guban oo leh geeso janjeedhsan.

Mararka qaarkood daloolka waxaa ka buuxa zeolite/calcite. Dhagaxan ayaa u adkeysanaya in sayaxa uu qaboojiyo (baraxan), ma aha mid nadiif ah (biyo la nuugo). Leh guryaha kulaylka hooseeya. Awoodda cadaadiska inta u dhaxaysa 30 – 20 kg / cm2. Halabuurka ugu muhiimsan ee macdanta silicate amorphous.

Iyada oo ku saleysan qaabka loo sameeyay (dejinta), qaybinta cabbirka walxaha (jajabin) iyo walxaha asalka ah, kaydka pumice ayaa loo kala saaray sidan soo socota:

Deegaan hoosaadka
Sub-aqueous

Ardante cusub; yacni kaydka ay sameysteen qulqulka tooska ah ee gaasaska ku jira lafaha, taasoo keentay isku dhafka jajabyada kala duwan ee qaabka matrixka.
Natiijada dib-u-dhigista (dib u dhigista)

Laga soo bilaabo metamorphosis, kaliya meelaha fulkaanaha ah ayaa yeelan doona kayd dhaqaale oo bam ah. Da’da juquraafiyeed ee dhigaalkani waa inta u dhaxaysa heer jaamacadeed iyo hadda. Volcano-yada firfircoon ee xilligaan juquraafi ahaan waxaa ka mid ahaa cirifka badweynta Baasifigga iyo waddada ka timaada badda Mediterranean-ka ilaa Himalayas ka dibna aada Bariga Hindiya.

Dhagaxyada la midka ah boombaleyaasha kale waa pumicite iyo dhoobada volcano. Pumicite waxay leedahay isku mid ka kooban kiimiko, asalka samaynta iyo qaab dhismeedka muraayadda sida bamka. Farqiga u dhexeeya ayaa ah oo keliya cabbirka walxaha, kaas oo ka yar dhexroorka 16 inji. Pumice waxaa laga helaa meel u dhow halka uu ka yimid, halka pumicite ay dabayshu qaadaysay masaafo aad u badan, waxaana lagu kaydiyay qaab ururin dambas oo heersare ah ama sida wasakh tuff ah.

Qoryaha foolkaanaha ayaa leh jajab guduudan ama madow, kuwaas oo la xareeyay intii lagu jiray qarxinta dhagaxa basaltic-ka ee ka imanayay foolkaanaha. Inta badan kaydka sariiraha waxaa laga helaa sida jajab gogol gogosha oo u dhexeeya 1 inch ilaa dhowr inji oo dhexroor ah.

Suuragalnimada Indooniisiya Pumice

Indooniisiya, joogitaanka pumice had iyo jeer waxay la xiriirtaa taxane Volcano ah oo Quaternary ilaa Tertiary ah. Qaybinteedu waxay dabooshaa aagagga Serang iyo Sukabumi (West Java), jasiiradda Lombok (NTB) iyo jasiiradda Ternate (Maluku).

Suurtagalnimada kaydka pumice ee leh ahmiyad dhaqaale iyo kayd aad u weyn ayaa ku yaal jasiiradda Lombok, Galbeedka Nusa Tenggara, jasiiradda Ternate, Maluku. Qadarka kaydka la cabbiray ee aagga waxa lagu qiyaasay in ka badan 10 milyan oo tan. Aagga Lombok, ka faa’iidaysiga bamka ayaa socday ilaa shan sano ka hor, halka Ternate ka faa’iidaysiga la sameeyay kaliya 1991.

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