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Mun bayar da rahoton shaidar haɓɓaka benen teku da fitar da iskar gas mai ƙarfi kilomita da dama daga tashar jiragen ruwa ta Naples (Italiya). Alamun ƙasa, tuddai da ramuka siffofi ne na benen teku. Waɗannan siffofi suna wakiltar saman ƙananan gine-ginen ɓawon ƙasa, gami da pagodas, kurakurai da naɗewa waɗanda ke shafar saman teku a yau. Sun yi rikodin ƙaruwa, matsi da sakin helium da carbon dioxide a cikin halayen decarbonization na narkewar mantle da duwatsun ɓawon ƙasa. Waɗannan iskar gas ɗin suna kama da waɗanda ke ciyar da tsarin hydrothermal na Ischia, Campi Flegre da Soma-Vesuvius, suna nuna tushen mantle da aka gauraya da ruwan ɓawon ƙasa a ƙarƙashin Tekun Naples. Faɗaɗa da fashewa a ƙarƙashin teku sakamakon aikin ɗaga iskar gas da matsi yana buƙatar matsin lamba mai yawa na 2-3 MPa. Haɓaka benen teku, kurakurai, da fitar da iskar gas alamu ne na girgizar ƙasa mara ƙarfi wanda zai iya haifar da fashewar benen teku da/ko fashewar hydrothermal.
Fitar da ruwa mai zurfi (ruwan zafi da iskar gas) a cikin teku abu ne da aka saba gani a tsakanin tsaunukan tsakiyar teku da kuma gefen farantin da ke haɗuwa (gami da sassan tsibiran da ke ƙarƙashinsu), yayin da fitar da iskar gas mai sanyi (chlatrates) galibi suna da alaƙa da ɗakunan ajiya na nahiyar da kuma gefen da ba a iya amfani da su ba1, 2, 3, 4, 5. Faɗuwar fitar da ruwa mai zafi a ƙasan teku a yankunan bakin teku yana nufin tushen zafi (ma'ajiyar magma) a cikin ɓawon nahiya da/ko mantle. Waɗannan fitar da ruwa na iya kafin hawan magma ta saman saman ɓawon duniya kuma ya kai ga fashewa da sanya tuddan teku na aman wuta. Saboda haka, gano (a) yanayin da ke da alaƙa da nakasar ƙasa mai aiki da kuma (b) fitar da iskar gas kusa da yankunan bakin teku da ke da yawan jama'a kamar yankin aman wuta na Naples a Italiya (kimanin mutane miliyan 1) yana da mahimmanci don tantance yiwuwar aman wuta. Fashewar ruwa mai zurfi. Bugu da ƙari, yayin da siffofin yanayin da ke da alaƙa da fitar da iskar gas mai zurfi ko ruwa mai tsafta a cikin teku sananne ne saboda halayen ƙasa da na halitta, keɓancewa siffofi ne na yanayin da ke da alaƙa da ruwa mai zurfi, sai dai waɗanda ke faruwa a Tafkin 12, akwai ƙananan bayanai kaɗan. A nan, mun gabatar da sabbin bayanai game da yanayin ruwa, girgizar ƙasa, ginshiƙin ruwa, da kuma yanayin ƙasa don yankin ruwa, yanayi da kuma tsari mai sarkakiya da hayakin iskar gas ya shafa a Tekun Naples (Kudancin Italiya), kimanin kilomita 5 daga tashar jiragen ruwa ta Naples. An tattara waɗannan bayanai a lokacin balaguron jirgin ruwa na SAFE_2014 (Agusta 2014) a cikin jirgin ruwa na R/V Urania. Muna bayyana kuma muna fassara tsarin ƙasa da ƙasa inda hayakin iska ke faruwa, muna bincika tushen ruwa mai fitar da iska, muna gano kuma muna fayyace hanyoyin da ke daidaita hauhawar iskar gas da nakasar da ke tattare da ita, kuma muna tattauna tasirin aman wuta.
Tekun Naples ya samar da gefen yamma na Plio-Quaternary, yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin arewa maso yamma na yankin kudu ... Nazarin 19,20 ya nuna cewa akwai alaƙa tsakanin yanayin Soma-Vesuvius da na Campi Flegre, wataƙila yana da alaƙa da ma'ajiyar magma guda ɗaya mai zurfi. Ayyukan aman wuta da girgizar ƙasa a cikin 36 ka na ƙarshe na Campi Flegrei da 18 ka na Somma Vesuvius sun sarrafa tsarin laka na Tekun Naples. Ƙarancin matakin teku a matsakaicin glacial na ƙarshe (18 ka) ya haifar da koma bayan tsarin laka mai zurfi na teku, wanda daga baya ya cika da abubuwan da suka faru a lokacin Late Pleistocene-Holocene. An gano hayakin iskar gas na ƙarƙashin ruwa a kusa da tsibirin Ischia da kuma bakin tekun Campi Flegre da kuma kusa da Dutsen Soma-Vesuvius (Hoto na 1b).
(a) Tsarin siffofi da tsarin ginin shiryayyen nahiyar da Tekun Naples 15, 23, 24, 48. Digogi manyan cibiyoyin fashewar jirgin ruwa ne; layukan ja suna wakiltar manyan kurakurai.(b) Bathymetry na Bay of Naples tare da gano iskar ruwa (digogi) da alamun layukan girgizar ƙasa (layukan baƙi). Layukan rawaya sune hanyoyin layin girgizar ƙasa L1 da L2 da aka ruwaito a Hoto na 6. Iyakokin gine-ginen Banco della Montagna (BdM) masu kama da kusurwoyi an yi musu alama da layuka masu shuɗi a cikin (a,b). Murabba'ai masu launin rawaya suna nuna wuraren da bayanan ginshiƙan ruwan acoustic suka bayyana, kuma an ruwaito firam ɗin CTD-EMBlank, CTD-EM50 da ROV a Hoto na 5. Da'irar rawaya tana nuna wurin da aka fitar da iskar gas, kuma an nuna abun da ke ciki a cikin Tebur S1. Golden Software (http://www.goldensoftware.com/products/surfer) yana amfani da zane-zane da Surfer® 13 ya samar.
Dangane da bayanan da aka samu a lokacin jirgin ruwa na SAFE_2014 (Agusta 2014) (duba Hanyoyi), an gina sabon Tsarin Ƙasa na Dijital (DTM) na Tekun Naples mai ƙudurin mita 1. DTM ya nuna cewa benen teku a kudancin Tashar Jiragen Ruwa ta Naples yana da siffar wani yanki mai gangara a hankali wanda ke fuskantar kudu (gangarawa ≤3°) wanda aka katse shi da wani tsari mai kama da kusurwoyi mai tsawon kilomita 5.0 × 5.3, wanda aka fi sani da Banco della Montagna (BdM). Hoto 1a,b).BdM yana tasowa a zurfin kimanin mita 100 zuwa 170, mita 15 zuwa 20 sama da benen teku da ke kewaye. Dutse na BdM ya nuna yanayin tudu saboda tudun da ke ƙasa da oval (Hoto na 2a), mazugi 665, da ramuka 30 (Hoto na 3 da 4). Tudun yana da matsakaicin tsayi da kewaye na mita 22 da 1,800, bi da bi. Da'irar [C = 4π(yanki/gefen 2)] na tudun ya ragu tare da ƙaruwar kewaye (Hoto na 2b). Rabon axial na tudun ya kasance tsakanin 1 da 6.5, tare da tudun da ke da rabon axial >2 yana nuna bugun N45°E + 15° da kuma bugun N105°E da aka watsar da shi, wanda ya fi warwatse da kuma bugun N105°E zuwa N145°E (Hoto na 2c). Mazugi ɗaya ko ɗaya da aka daidaita suna nan a kan jirgin BdM da kuma saman tudun (Hoto na 3a,b). Tsarin mazugi yana bin tsarin tudun da suke a kai. Alamun mazugi galibi suna kan tudun teku mai faɗi (Hoto na 3c) kuma lokaci-lokaci akan tudun. Yawan mazugi da alamun mazugi a sarari yana nuna cewa daidaitaccen tsarin NE-SW yana iyakance iyakokin arewa maso gabas da kudu maso yamma na kurfin BdM (Hoto na 4a,b); hanyar NW-SE mai ƙarancin tsayi tana cikin yankin BdM na tsakiya.
(a) Tsarin ƙasa na dijital (girman tantanin halitta 1 m) na kusurwoyin Banco della Montagna (BdM).(b) Gefen da zagayen tudun BdM.(c) Rabon axial da kusurwa (hanyar) na babban axis na ellipse mafi dacewa da ke kewaye da tudun. Kuskuren daidaitaccen samfurin Tsarin Ƙasa na Dijital shine 0.004 m; kurakuran daidaito na kewaye da zagaye sune 4.83 m da 0.01, bi da bi, kuma kurakuran daidaito na rabon axial da kusurwa sune 0.04 da 3.34°, bi da bi.
Cikakkun bayanai game da mazugi, ramuka, tuddai da ramuka da aka gano a yankin BdM da aka samo daga DTM a Hoto na 2.
(a) Daidaita mazugi a kan wani lebur na teku; (b) mazugi da ramuka a kan siraran tuddai na NW-SE; (c) alamun mazugi a kan wani wuri mai ɗan nutsewa.
(a) Rarraba sarari na ramuka, ramuka, da kuma fitar da iskar gas mai aiki.(b) Yawan ramuka da ramuka da aka ruwaito a cikin (a) (lamba/0.2 km2).
Mun gano hayakin iskar gas guda 37 a yankin BdM daga hotunan sauti mai kama da na ruwa na ROV da kuma lura kai tsaye na benen teku da aka samu a lokacin tafiyar jirgin ruwa na SAFE_2014 a watan Agusta 2014 (Hotuna na 4 da 5). Matsalolin acoustic na waɗannan hayakin suna nuna siffofi masu tsayi a tsaye suna tashi daga benen teku, suna tsakanin 12 zuwa kusan 70 m (Hoto na 5a). A wasu wurare, rashin daidaiton acoustic sun samar da "jirgin ƙasa" mai ci gaba. Abubuwan da aka lura da su sun bambanta sosai: daga kwararar kumfa mai yawa zuwa abubuwan da ba su daɗe ba (Fim na Ƙarin 1). Binciken ROV yana ba da damar tabbatar da gani na faruwar ramukan ruwa na benen teku kuma yana nuna ƙananan alamun pock a kan benen teku, wani lokacin ana kewaye da shi da laka ja zuwa lemu (Hoto na 5b). A wasu lokuta, tashoshin ROV suna sake kunna hayakin. Siffar iska tana nuna buɗewa mai zagaye a saman ba tare da walƙiya a cikin ginshiƙin ruwa ba. pH a cikin ginshiƙin ruwa kusa da wurin fitarwa ya nuna raguwa mai yawa, yana nuna ƙarin yanayin acidic a cikin gida (Hoto na 5c,d). Musamman, pH da ke sama da fitar iskar gas ta BdM a zurfin mita 75 ya ragu daga 8.4 (a zurfin mita 70) zuwa 7.8 (a zurfin mita 75) (Hoto na 5c), yayin da wasu wurare a Tekun Naples suna da ƙimar pH tsakanin mita 0 da 160 a cikin tazara tsakanin 8.3 da 8.5 (Hoto na 5d). An rasa manyan canje-canje a zafin ruwan teku da gishiri a wurare biyu a ciki da wajen yankin BdM na Tekun Naples. A zurfin mita 70, zafin jiki shine 15 °C kuma gishirin yana kusan 38 PSU (Hoto na 5c, d). An nuna ma'aunin pH, zafin jiki, da gishirin: a) halartar ruwan acidic da ke da alaƙa da tsarin cire iskar BdM da b) rashin ko fitar da ruwa mai zafi da ruwan gishiri a hankali.
(a) Tagar siyan bayanin ginshiƙin ruwa mai jikewa (echometer Simrad EK60). Madaurin kore mai tsayi wanda ya dace da fashewar iskar gas da aka gano a kan fitar da ruwan EM50 (kimanin mita 75 ƙasa da matakin teku) wanda ke cikin yankin BdM; ana kuma nuna siginar multiplex ta ƙasa da ta ƙasa (b) da aka tattara tare da abin hawa mai sarrafawa daga nesa a yankin BdM. Hoton guda ɗaya yana nuna ƙaramin rami (da'irar baƙi) kewaye da laka ja zuwa lemu. (c,d) Bayanan CTD na bincike mai yawa da aka sarrafa ta amfani da software na SBED-Win32 (Seasave, sigar 7.23.2). Tsarin sigogi da aka zaɓa (gishiri, zafin jiki, pH da iskar oxygen) na ginshiƙin ruwa sama da fitar da ruwan EM50 (panel c) da kuma wajen kwamitin yanki na fitar da Bdm (d).
Mun tattara samfuran iskar gas guda uku daga yankin binciken tsakanin 22 da 28 ga Agusta, 2014. Waɗannan samfuran sun nuna irin waɗannan abubuwan haɗin, waɗanda CO2 (934-945 mmol/mol) suka mamaye, sai kuma yawan N2 (37-43 mmol/mol), CH4 (16-24 mmol/mol) da H2S (0.10 mmol/mol) -0.44 mmol/mol), yayin da H2 da He ba su da yawa (<0.052 da <0.016 mmol/mol, bi da bi) (Hoto na 1b; Tebur S1, Fim ɗin Ƙarin Bayani na 2). An kuma auna yawan O2 da Ar mai yawa (har zuwa 3.2 da 0.18 mmol/mol, bi da bi). Jimlar hydrocarbons masu haske sun kama daga 0.24 zuwa 0.30 mmol/mol kuma sun ƙunshi alkanes na C2-C4, aromatics (galibi benzene), propene da mahadi masu ɗauke da sulfur (thiophene). Ƙimar 40Ar/36Ar ta yi daidai da iska (295.5), kodayake samfurin EM35 (BdM dome) yana da ƙimar 304, yana nuna ɗan wuce gona da iri na 40Ar. Rabon δ15N ya fi na iska (har zuwa +1.98% idan aka kwatanta da iska), yayin da ƙimar δ13C-CO2 ta kasance daga -0.93 zuwa 0.44% idan aka kwatanta da ƙimar V-PDB.R/Ra (bayan an gyara gurɓataccen iska ta amfani da rabon 4He/20Ne) sun kasance tsakanin 1.66 da 1.94, suna nuna kasancewar babban ɓangaren mantle He. Ta hanyar haɗa isotope na helium tare da CO2 da isotope ɗinsa mai karko 22, za a iya ƙara fayyace tushen hayakin da ke cikin BdM. A cikin taswirar CO2 don CO2/3He idan aka kwatanta da δ13C (Hoto na 6), an kwatanta haɗin iskar BdM da na Ischia, Campi Flegrei da Somma-Vesuvius fumaroles. Hoto na 6 kuma yana ba da rahoton layukan haɗakar ka'idoji. tsakanin tushen carbon guda uku daban-daban waɗanda za su iya shiga cikin samar da iskar gas ta BdM: narkewar da aka narkar daga mantle, laka mai wadataccen halitta, da carbonates. Samfuran BdM sun faɗi akan layin haɗawa wanda dutsen mai aman wuta na Campania guda uku suka nuna, wato, haɗuwa tsakanin iskar gas ta mantle (waɗanda ake tsammanin an wadatar da su kaɗan da carbon dioxide idan aka kwatanta da MORBs na gargajiya don daidaita bayanai) da kuma halayen da ke haifar da rushewar iskar gas. Dutse mai iskar gas da ya haifar.
An bayar da rahoton layukan haɗin gwiwa tsakanin abun da ke cikin mantle da kuma ƙarshen manne na dutse mai laushi da kuma na halitta don kwatantawa. Akwatuna suna wakiltar yankunan fumarole na Ischia, Campi Flegrei da Somma-Vesvius 59, 60, 61. Samfurin BdM yana cikin yanayin gauraye na aman wuta na Campania. Iskar gas ɗin ƙarshen layin gauraye na tushen mantle ne, wanda shine iskar da aka samar ta hanyar sake fasalin ma'adanai na carbonate.
Sassan girgizar ƙasa L1 da L2 (Hotuna 1b da 7) suna nuna sauyawa tsakanin BdM da jerin sassan stratigraphic na yankunan Somma-Vesuvius (L1, Hoto na 7a) da Campi Flegrei (L2, Hoto na 7b) na aman wuta. BdM yana da alaƙa da kasancewar manyan tsarin girgizar ƙasa guda biyu (MS da PS a Hoto na 7). Na sama (MS) yana nuna masu nuna haske masu kama da juna na girma zuwa matsakaici da ci gaba a gefe (Hoto na 7b,c). Wannan Layer ya haɗa da laka na ruwa da tsarin Last Glacial Maximum (LGM) ya ja kuma ya ƙunshi yashi da yumbu23. Layer na PS na ƙasa (Hoto na 7b–d) yana da siffa ta wani lokaci mai rikitarwa zuwa mai haske a siffar ginshiƙai ko gilashin awa. Saman laka na PS ya samar da tuddai na ƙasa (Hoto na 7d). Waɗannan geometries masu kama da diapir suna nuna kutsewar kayan PS masu haske a cikin ma'ajiyar MS mafi girma. Uplift yana da alhakin ƙirƙirar naɗewa da kurakurai waɗanda ke shafar Layer ɗin MS da kuma rufin ƙasan teku na BdM da ke samansa a yanzu (Hoto na 7b–d). Tazarar stratigraphic ta MS a bayyane take a cikin ɓangaren ENE na sashin L1, yayin da yake fari zuwa BdM saboda kasancewar wani Layer mai cike da iskar gas (GSL) wanda wasu matakan ciki na jerin MS suka rufe (Hoto na 7a). Kwayar nauyi da aka tattara a saman BdM wanda ya dace da layin girgizar ƙasa mai haske yana nuna cewa saman 40 cm ya ƙunshi yashi da aka ajiye kwanan nan zuwa yanzu; )24,25 da gutsuttsuran da suka fito daga fashewar fashewar Campi Flegrei na "Naples Yellow Tuff" (14.8 ka)26. Ba za a iya bayyana matakin haske na Layer PS ta hanyar tsarin hadawa mai cike da rudani ba, saboda layukan rudani da ke da alaƙa da zaftarewar ƙasa, kwararar laka da kwararar pyroclastic da aka samu a wajen BdM a Tekun Naples ba su da haske sosai21,23,24. Mun kammala da cewa abubuwan da aka lura da su na girgizar ƙasa ta BdM PS da kuma bayyanar Layer PS na ƙarƙashin teku (Hoto na 7d) suna nuna ɗaga iskar gas.
(a) Bayanin girgizar ƙasa mai layi ɗaya L1 (layin kewayawa a Hoto na 1b) yana nuna tsarin sarari mai ginshiƙi (pagoda). Pagoda ya ƙunshi ma'adinan da ke cike da rudani na pumice da yashi. Layin da ke cike da iskar gas wanda ke ƙarƙashin pagoda yana kawar da ci gaba da samuwar zurfi.(b) Bayanin girgizar ƙasa mai tashoshi ɗaya L2 (layin kewayawa a Hoto na 1b), yana nuna yankewa da nakasa na tuddan ƙasa na teku, marine (MS), da ma'adinan yashi mai kauri (PS).(c) An ruwaito bayanan nakasa a cikin MS da PS a cikin (c,d). Idan aka ɗauka cewa gudun 1580 m/s a cikin laka mafi girma, 100 ms yana wakiltar kusan m 80 a sikelin tsaye.
Halayen siffar BdM da tsarinsu sun yi kama da sauran filayen hydrothermal da gas hydrate a ƙarƙashin teku a duniya2,12,27,28,29,30,31,32,33,34 kuma galibi ana danganta su da ɗagawa (ruwa da tuddai) da fitar iskar gas (mazugi, ramuka). Mazugi da ramuka masu tsayi da tuddai masu daidaitawa na BdM suna nuna ikon shiga cikin tsari (Hotuna na 2 da 3). Tsarin sararin samaniya na tuddai, ramuka da hanyoyin iska masu aiki yana nuna cewa rarrabawarsu wani ɓangare ne ke ƙarƙashin karyewar tasirin NW-SE da NE-SW (Hoto na 4b). Waɗannan su ne mafi kyawun hare-haren tsarin kurakurai da ke shafar yankunan aman wuta na Campi Flegrei da Somma-Vesuvius da Tekun Naples. Musamman ma, tsarin na farko yana sarrafa wurin fitar da hydrothermal daga ramin Campi Flegrei35. Saboda haka mun kammala da cewa kurakurai da karyewa a Tekun Naples suna wakiltar hanyar da aka fi so don ƙaura da iskar gas zuwa saman, fasalin da wasu hydrothermal masu sarrafawa a tsarin suka raba. tsarin36,37. Abin lura shi ne, ba koyaushe ake danganta mazugi da ramukan BdM da tuddai ba (Hoto na 3a,c). Wannan yana nuna cewa waɗannan tuddai ba lallai bane su wakilci abubuwan da suka riga suka fara samuwar ramuka, kamar yadda wasu marubuta suka ba da shawara ga yankunan da ke ɗauke da iskar gas32,33. Kammalawarmu ta goyi bayan hasashen cewa rushewar laka a ƙasan teku ba koyaushe ke haifar da samuwar ramuka ba.
Haɗakar iskar gas guda uku da aka tattara sun nuna alamun sinadarai da suka saba da ruwan hydrothermal, musamman CO2 tare da yawan iskar gas mai rage (H2S, CH4 da H2) da kuma ƙananan hydrocarbons (musamman benzene da propylene)38,39, 40, 41, 42, 43, 44, 45 (Tebur S1). Kasancewar iskar gas mai yanayi (kamar O2), waɗanda ba a tsammanin suna cikin hayakin ƙarƙashin ruwa, na iya zama saboda gurɓatawa daga iskar da aka narkar a cikin ruwan teku da ta haɗu da iskar gas da aka adana a cikin akwatunan filastik da aka yi amfani da su don ɗaukar samfur, kamar yadda ake cire ROVs daga ƙasan teku zuwa teku don tayar da zaune tsaye. Akasin haka, ƙimar δ15N mai kyau da babban N2/Ar (har zuwa 480) mafi girma fiye da ASW (ruwa mai cike da iska) suna nuna cewa yawancin N2 ana samar da su ne daga tushen waje, bisa ga asalin hydrothermal na waɗannan iskar gas. Asalin iskar gas mai ƙarfi da aman wuta na BdM an tabbatar da shi ta hanyar abubuwan da ke cikin CO2 da He da isotopic ɗinsu. sa hannu. Isotopes na Carbon (δ13C-CO2 daga -0.93% zuwa +0.4%) da ƙimar CO2/3He (daga 1.7 × 1010 zuwa 4.1 × 1010) suna nuna cewa samfuran BdM suna cikin yanayin gauraye na fumaroles a kusa da membobin ƙarshen mantle na Gulf of Naples da kuma decarbonization. Alaƙa tsakanin iskar gas da amsawar ta samar (Hoto na 6). Musamman ma, samfuran iskar gas na BdM suna kan yanayin gaurayawa a kusan wuri ɗaya da ruwa daga tsaunukan aman wuta na Campi Flegrei da Somma-Veusivus da ke kusa. Sun fi ɓawon Ischia fumaroles, waɗanda ke kusa da ƙarshen mantle. Somma-Vesuvius da Campi Flegrei suna da ƙimar 3He/4He mafi girma (R/Ra tsakanin 2.6 da 2.9) fiye da BdM (R/Ra tsakanin 1.66 da 1.96; Tebur S1). Wannan yana nuna cewa ƙari da tarin radiation Ya samo asali ne daga tushen magma guda ɗaya da ke ciyar da aman wutar Somma-Vesuvius da Campi Flegrei. Rashin sassan carbon na halitta da za a iya ganowa a cikin hayakin BdM yana nuna cewa laka ba ta da hannu a cikin tsarin cire gass na BdM.
Dangane da bayanan da aka ruwaito a sama da kuma sakamakon gwaje-gwajen tsarin gine-gine masu kama da kumfa da ke da alaƙa da yankuna masu arzikin iskar gas a ƙarƙashin teku, matsin lamba mai zurfi na iya zama alhakin ƙirƙirar kumbon BdM mai sikelin kilomita. Don kimanta matsin lamba mai yawa da ke kaiwa ga wurin ajiyar BdM, mun yi amfani da samfurin makanikai na farantin sirara33,34 muna ɗauka, daga bayanan morphological da girgizar ƙasa da aka tattara, cewa wurin ajiyar BdM takardar ƙaramin da'ira ce ta radius wacce ta fi girma fiye da wurin ajiyar mai laushi mai laushi mai laushi. Matsakaicin motsi a tsaye w da kauri h na (Ƙarin Hoto na S1).Pdef shine bambanci tsakanin jimlar matsin lamba da matsin lamba mai tsauri da matsin lamba na ruwa. A BdM, radius ɗin yana da kusan 2,500 m, w shine 20 m, kuma matsakaicin h da aka kiyasta daga bayanin girgizar ƙasa shine kusan m 100. Muna ƙididdige Pdef 46Pdef = w 64 D/a4 daga alaƙar, inda D shine taurin lanƙwasa; An bayar da D ta hanyar (E h3)/[12(1 – ν2)], inda E shine tsarin Young na ajiya, ν shine rabon Poisson (~0.5)33. Tunda ba za a iya auna halayen injiniya na laka na BdM ba, mun saita E = 140 kPa, wanda shine ƙima mai ma'ana ga laka na bakin teku 47 kama da BdM14,24. Ba mu la'akari da mafi girman ƙimar E da aka ruwaito a cikin wallafe-wallafen laka na laka mai laushi (300 < E < 350,000 kPa)33,34 ba saboda laka na BDM ya ƙunshi yashi, ba laka ko laka mai laushi ba24. Mun sami Pdef = 0.3 Pa, wanda ya yi daidai da kimantawar hanyoyin ɗaga bene na teku a cikin yanayin kwarin gas, inda Pdef ya bambanta daga 10-2 zuwa 103 Pa, tare da ƙananan ƙima wakiltar ƙasa w/a da/ko menene. A cikin BdM, rage tauri saboda cikar iskar gas na gida na laka. da/ko bayyanar karyewar da ta riga ta faru na iya taimakawa wajen gazawa da kuma fitar da iskar gas, wanda hakan ke ba da damar samar da tsarin iskar da aka lura. Bayanan girgizar ƙasa da aka tattara (Hoto na 7) sun nuna cewa an ɗaga lakaran PS daga GSL, wanda hakan ke tura lakaran ruwa na MS da ke saman su, wanda hakan ke haifar da tuddai, lanƙwasawa, kurakurai, da yanke laka (Hoto na 7b,c). Wannan yana nuna cewa tsohon laka mai girman kaso 14.8 zuwa 12 ya shiga cikin ƙaramin lakaran MS ta hanyar tsarin jigilar iskar gas sama. Ana iya ganin siffofin tsarin BdM a matsayin sakamakon matsin lamba da fitar da ruwa da GSL ta samar ya haifar. Ganin cewa ana iya ganin fitar da ruwa mai aiki daga ƙasan teku har zuwa sama da 170 m bsl48, muna ɗauka cewa matsin lamba mai yawa a cikin GSL ya wuce 1,700 kPa. Hawan iskar gas a cikin laka kuma yana da tasirin goge kayan da ke cikin MS, yana bayyana kasancewar laka mai rudani a cikin lakaran nauyi da aka samo a kan BdM25. Bugu da ƙari, matsin lamba mai yawa na GSL yana haifar da tsarin karyewa mai rikitarwa (laifi mai girman polygonal a Hoto na 7b). A hade, wannan yanayin, tsari, da daidaitawar stratigraphic, wanda aka kira "pagodas"49,50, an danganta su da tasirin sakandare na tsoffin samuwar ƙanƙara, kuma a halin yanzu ana fassara su a matsayin tasirin hauhawar iskar gas31,33 ko evaporites50. A gefen nahiyar Campania, laka mai ƙazanta ba ta da yawa, aƙalla a cikin mafi girman kilomita 3 na ɓawon. Saboda haka, tsarin girma na pagodas na BdM yana iya sarrafawa ta hanyar hauhawar iskar gas a cikin laka. Wannan ƙarshe yana da goyon bayan facies na girgizar ƙasa mai haske na pagoda (Hoto na 7), da kuma bayanan tushen nauyi kamar yadda aka ruwaito a baya24, inda yashi na yanzu ya fashe tare da 'Pomici Principalli'25 da 'Naples Yellow Tuff'26 Campi Flegrei. Bugu da ƙari, ajiyar PS sun mamaye kuma sun lalata saman saman MS. (Hoto na 7d). Wannan tsarin tsari yana nuna cewa pagoda tana wakiltar tsarin tayar da zaune tsaye ba wai kawai bututun iskar gas ba. Don haka, manyan matakai guda biyu ne ke jagorantar samuwar pagoda: a) yawan laka mai laushi yana raguwa yayin da iskar gas ke shiga daga ƙasa; b) haɗuwar iskar gas da ƙasa tana ƙaruwa, wanda shine abin da aka lura yana naɗewa, kurakurai da karyewa Sanadin ajiyar MS (Hoto na 7). An gabatar da irin wannan tsarin samuwar pagodas da ke da alaƙa da iskar gas hydrates a Tekun Kudancin Scotia (Antarctica). Pagodas na BdM sun bayyana a cikin ƙungiyoyi a yankunan tuddai, kuma matsakaicin girmansu a tsaye ya kai mita 70-100 a cikin lokacin tafiya ta hanyoyi biyu (TWTT) (Hoto na 7a). Saboda kasancewar undulations na MS da kuma la'akari da tsarin BdM gravity core, mun ɗauka cewa shekarun samuwar tsarin pagoda bai kai kimanin kadada 14-12 ba. Bugu da ƙari, ci gaban waɗannan gine-gine har yanzu yana aiki (Hoto na 7d) yayin da wasu pagodas suka mamaye kuma suka lalata yashi na BdM na yanzu (Hoto na 7d).
Rashin hayewa kan gadon teku na yanzu yana nuna cewa (a) hauhawar iskar gas da/ko dakatar da haɗakar iskar gas da ruwa a gida, da/ko (b) yuwuwar kwararar iskar gas da ruwa a gefe ba ta ba da damar aiwatar da matsin lamba na gida ba. Dangane da samfurin ka'idar diapir52, kwararar iskar gas tana nuna daidaito mara kyau tsakanin yawan samar da cakuda laka da iskar gas daga ƙasa da kuma yadda pagoda ke motsawa sama. Ragewar yawan samar da iskar gas na iya danganta da ƙaruwar yawan cakuda saboda ɓacewar iskar gas. Sakamakon da aka taƙaita a sama da haɓakar iskar pagoda da ke sarrafa ruwa yana ba mu damar kimanta tsayin ginshiƙin iska hg. Ana ba da iskar ta ΔP = hgg (ρw – ρg), inda g shine nauyi (9.8 m/s2) da ρw da ρg sune yawan ruwa da iskar gas, bi da bi. ΔP shine jimlar Pdef da aka ƙididdige a baya da matsin lamba na lithostatic Plith na farantin laka, watau ρsg h, inda ρs shine yawan laka. A wannan yanayin, ƙimar hg da ake buƙata don buoyancy da ake so ana bayar da ita ta hanyar hg = (Pdef + Plith)/[g (ρw – ρg)]. A cikin BdM, mun saita Pdef = 0.3 Pa da h = 100 m (duba sama), ρw = 1,030 kg/m3, ρs = 2,500 kg/m3, ρg ba shi da yawa saboda ρw ≫ρg. Muna samun hg = 245 m, ƙimar da ke wakiltar zurfin ƙasan GSL.ΔP shine 2.4 MPa, wanda shine matsin lamba da ake buƙata don karya benen teku na BdM da kuma samar da iska.
Tsarin iskar gas ta BdM ya yi daidai da tushen mantle da aka canza ta hanyar ƙara ruwaye da ke da alaƙa da halayen decarbonization na duwatsun crustal (Hoto na 6). Daidaito mai ƙarfi na EW na domes na BdM da aman wuta masu aiki kamar Ischia, Campi Flegre, da Soma-Vesuvius, tare da haɗin iskar gas da aka fitar, yana nuna cewa iskar gas da aka fitar daga mantle ɗin da ke ƙasa da yankin aman wuta na Naples sun gauraye. Ƙarin ruwayen crustal suna motsawa daga yamma (Ischia) zuwa gabas (Somma-Vesuivus) (Hoto na 1b da 6).
Mun kammala da cewa a Tekun Naples, 'yan kilomita kaɗan daga tashar jiragen ruwa ta Naples, akwai wani tsari mai faɗin kilomita 25 mai kama da kusurwoyi wanda tsarin cire gas mai aiki ke shafar shi kuma yana faruwa ne sakamakon sanya pagodas da tuddai. A halin yanzu, sa hannun BdM yana nuna cewa girgizar ƙasa mara magmatic53 na iya faruwa kafin fitowar aman wuta na tayi, watau fitowar magma da/ko ruwan zafi da wuri. Ya kamata a aiwatar da ayyukan sa ido don nazarin juyin halittar abubuwan da suka faru da kuma gano alamun geochemical da geophysical waɗanda ke nuna yiwuwar rikice-rikicen magmatic.
An samo bayanan ginshiƙan ruwa na Acoustic (2D) a lokacin jirgin ruwa na SAFE_2014 (Agusta 2014) a kan jirgin ruwa na R/V Urania (CNR) ta Cibiyar Muhalli ta Tekun Ruwa (IAMC). An yi amfani da na'urar sauti mai ratsa haske ta kimiyya mai suna Simrad EK60 wacce ke aiki a 38 kHz. An yi rikodin bayanan sauti a matsakaicin gudu na kimanin kilomita 4. An yi amfani da hotunan echosounder da aka tattara don gano fitar ruwa da kuma ayyana wurin da suke a yankin da aka tattara (tsakanin 74 da 180 m bsl). Auna sigogi na zahiri da na sinadarai a cikin ginshiƙin ruwa ta amfani da na'urori masu auna sigina da yawa (inductiveivity, zafin jiki da zurfin, CTD). An tattara bayanai ta amfani da na'urar CTD 911 (SeaBird, Electronics Inc.) kuma an sarrafa su ta amfani da software na SBED-Win32 (Seasave, sigar 7.23.2). An yi duba na gani na gefen teku ta amfani da na'urar ROV ta "Pollux III" (GEItaliana) (abin hawa mai aiki daga nesa) tare da kyamarori biyu (ƙananan da manyan).
An gudanar da tattara bayanai na Multibeam ta amfani da tsarin sonar mai girman 100 KHz Simrad EM710 (Kongsberg). Tsarin yana da alaƙa da tsarin matsayi na duniya daban-daban don tabbatar da kurakuran ƙananan ma'auni a cikin matsayin haske. Bugawar sauti tana da mita 100 KHz, bugun harbi na digiri 150 da kuma buɗewar duka haskoki 400. Auna kuma a yi amfani da bayanan saurin sauti a ainihin lokacin yayin saye. An sarrafa bayanai ta amfani da software na PDS2000 (Reson-Thales) bisa ga ƙa'idar Ƙungiyar Kula da Yanayi ta Duniya (https://www.iho.int/iho_pubs/standard/S-44_5E.pdf) don kewayawa da gyaran ruwa. An yi rage hayaniya saboda ƙaruwar kayan aiki da rashin ingancin cire haskoki ta hanyar gyara band da kayan aikin cire haskoki. Ana ci gaba da gano saurin sauti ta hanyar tashar keel da ke kusa da na'urar watsa haske mai yawan haske kuma tana samun kuma tana amfani da bayanan saurin sauti na ainihin lokaci a cikin ginshiƙin ruwa kowane awa 6-8 don samar da saurin sauti na ainihin lokaci ga Tuƙi mai kyau. Duk bayanan sun ƙunshi kimanin kilomita 440 (zurfin mita 0-1200). An yi amfani da bayanan don samar da samfurin ƙasa mai ƙuduri mai girma (DTM) wanda aka siffanta shi da girman tantanin halitta mai girman mita 1. An yi DTM na ƙarshe (Hoto na 1a) da bayanan ƙasa (> mita 0 sama da matakin teku) da Cibiyar Geo-Soja ta Italiya ta samu a girman tantanin halitta mai girman mita 20.
Bayanin bayanan girgizar ƙasa mai tsawon kilomita 55 mai ƙuduri mai girma, wanda aka tattara a lokacin balaguron teku mai aminci a 2007 da 2014, ya rufe yanki na kusan murabba'in kilomita 113, duka a kan R/V Urania. An samo bayanan martaba na Marisk (misali, bayanin girgizar ƙasa na L1, Hoto na 1b) ta amfani da tsarin IKB-Seistec boomer. Na'urar da aka samo ta ƙunshi catamaran mai tsawon mita 2.5 wanda aka sanya tushen da mai karɓa. Sa hannun tushen ya ƙunshi kololuwa ɗaya mai kyau wanda aka siffanta a cikin kewayon mita 1-10 kHz kuma yana ba da damar warware masu haskakawa da aka raba da cm 25. An samo bayanan girgizar ƙasa mai aminci ta amfani da tushen girgizar ƙasa mai girman 1.4 Kj mai yawa wanda aka haɗa tare da software na Geotrace (Tsarin Binciken Tekun Geo). Tsarin ya ƙunshi catamaran wanda ke ɗauke da tushen 1-6.02 KHz wanda ke ratsa har zuwa milise seconds 400 a cikin laka mai laushi a ƙarƙashin ƙasan teku, tare da ƙudurin tsaye na ka'ida na 30 cm. An samo na'urorin Safe da Marsik duka a cikin saurin harbi 0.33/dakika tare da saurin jirgin ruwa <3 Kn. An sarrafa kuma an gabatar da Data ta amfani da software na Geosuite Allworks tare da aikin aiki mai zuwa: gyaran faɗaɗawa, rage girman ginshiƙin ruwa, tace IIR mai tsawon 2-6 KHz, da AGC.
An tattara iskar gas daga cikin ruwa mai zurfi a kan ƙasan teku ta amfani da akwatin filastik da aka sanya masa roba diaphragm a gefensa na sama, wanda ROV ya juye a kan hanyar iskar. Da zarar kumfa na iska da ke shiga akwatin sun maye gurbin ruwan teku gaba ɗaya, ROV zai koma zurfin mita 1, kuma mai nutsewa ya tura iskar gas da aka tattara ta cikin septum na roba zuwa kwalaben gilashi guda biyu masu girman milimita 60 da aka riga aka kwashe tare da sandunan dakatarwa na Teflon wanda aka cika Ɗaya da 20 mL na maganin 5N NaOH (flask na Gegenbach). Babban nau'in iskar acid (CO2 da H2S) suna narkewa a cikin maganin alkaline, yayin da nau'in iskar gas mai ƙarancin narkewa (N2, Ar+O2, CO, H2, He, Ar, CH4 da hydrocarbons masu sauƙi) ana adana su a cikin sararin kwalbar samfurin. An bincika iskar gas mara narkewa ta hanyar gas chromatography (GC) ta amfani da Shimadzu 15A wanda aka sanye shi da ginshiƙin sieve na kwayoyin halitta na 5A mai tsawon mita 10 da na'urar gano yanayin zafi (TCD) 54.Argon da An yi nazarin O2 ta amfani da chromatograph ɗin iskar gas na Thermo Focus wanda aka sanya masa ginshiƙin sieve na ƙwayoyin halitta mai tsawon mita 30 da TCD. An yi nazarin methane da ƙananan hydrocarbons ta amfani da chromatograph ɗin iskar gas na Shimadzu 14A wanda aka sanye da ginshiƙin bakin ƙarfe mai tsawon mita 10 wanda aka cika da ragar Chromosorb PAW 80/100, wanda aka shafa da 23% SP 1700 da na'urar gano ionization mai harshen wuta (FID). An yi amfani da matakin ruwa don nazarin 1) CO2, kamar yadda aka sanya shi da maganin HCl na 0.5 N (Metrohm Basic Titrino) da 2) H2S, kamar yadda, bayan oxidation tare da 5 mL H2O2 (33%), ta hanyar ion chromatography (IC) (IC) (Wantong 761). Kuskuren nazari na titration, GC da nazarin IC bai kai 5% ba. Bayan hanyoyin cirewa da tsarkakewa na yau da kullun don gaurayawan iskar gas, an yi nazarin 13C/12C CO2 (wanda aka bayyana a matsayin δ13C-CO2% da V-PDB) ta amfani da na'urar auna ma'aunin Finningan Delta S 55,56. Ma'aunin da aka yi amfani da shi don kimanta daidaiton waje sune marmara na Carrara da San Vincenzo (na ciki), NBS18 da NBS19 (na ƙasashen waje), yayin da kuskuren nazari da sake samarwa suka kasance ±0.05% da ±0.1%, bi da bi.
An tantance ƙimar δ15N (wanda aka bayyana a matsayin % vs. Air) da 40Ar/36Ar ta amfani da na'urar Agilent 6890 N gas chromatograph (GC) da aka haɗa zuwa na'urar Finnigan Delta plusXP mai ci gaba da kwararar mass spectrometer. Kuskuren bincike shine: δ15N±0.1%, 36Ar<1%, 40Ar<3%. Rabon isotope na He (wanda aka bayyana a matsayin R/Ra, inda R shine 3He/4He wanda aka auna a cikin samfurin kuma Ra shine rabo ɗaya a cikin yanayi: An tantance 1.39 × 10−6)57 a dakin gwaje-gwaje na INGV-Palermo (Italiya). An tantance 3He, 4He da 20Ne ta amfani da na'urar auna taro mai tara abubuwa biyu (Helix SFT-GVI)58 bayan rabuwar He da Ne. Kuskuren nazari ≤ 0.3%. Matsakaicin blanks na He da Ne sune <10-14 da <10-16 mol, bi da bi.
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