地震地质
地震地質
지진지질
SEISMOLOGY AND GEOLOGY
2009年
4期
628-638
,共11页
张秉良%赵波%于红梅%许建东%史兰斌%郑勇刚%盘晓东
張秉良%趙波%于紅梅%許建東%史蘭斌%鄭勇剛%盤曉東
장병량%조파%우홍매%허건동%사란빈%정용강%반효동
天池火山%x射线衍射%长石结构状态%温度
天池火山%x射線衍射%長石結構狀態%溫度
천지화산%x사선연사%장석결구상태%온도
Tianchi volcano%x ray diffraction%structural state of feldspar%temperature
利用扫描电镜和x射线衍射分析数据研究天池火山天文峰剖面全新世喷发物中的长石表面特征和结构状态,结果显示:天文峰剖面从顶部黑色浮岩向下到暗厌色浮岩中,长石表面比较新鲜,个别长石有极轻微风化,在长石颗粒表面凹处偶有沉积厚度不同的非晶质絮状物.长石为碱性长石中的高透长石-高钠长石系列,特征衍射峰的强度、面网d值与歪长石PDF数据基本相符,物相组成为(0r37~41,Ab63~59),表明天池火山喷发物中的长石属歪长石;长石有序度介于0.045~0.089之间;η参数介于-1.010~-1.361之间;最低结品温度为800~990℃,且顶部黑色浮岩中长石的最低结晶温度高达990℃.研究认为,有天池火山喷发的年代越新,长石有序度越低,其结构状态所记录的温度越高的趋势.目前测得的天池火山长石结构是由高温结构随温度下降转变而来,因此天池火山长石最初形成的温度可能更高.天池火山全新世喷发物中长石结构状态特征的差异可能与火山喷发的年代、喷发温度有关.研究天池火山全新世喷发物中的长石结构状态特征具有一定的理论和实际应用价值.
利用掃描電鏡和x射線衍射分析數據研究天池火山天文峰剖麵全新世噴髮物中的長石錶麵特徵和結構狀態,結果顯示:天文峰剖麵從頂部黑色浮巖嚮下到暗厭色浮巖中,長石錶麵比較新鮮,箇彆長石有極輕微風化,在長石顆粒錶麵凹處偶有沉積厚度不同的非晶質絮狀物.長石為堿性長石中的高透長石-高鈉長石繫列,特徵衍射峰的彊度、麵網d值與歪長石PDF數據基本相符,物相組成為(0r37~41,Ab63~59),錶明天池火山噴髮物中的長石屬歪長石;長石有序度介于0.045~0.089之間;η參數介于-1.010~-1.361之間;最低結品溫度為800~990℃,且頂部黑色浮巖中長石的最低結晶溫度高達990℃.研究認為,有天池火山噴髮的年代越新,長石有序度越低,其結構狀態所記錄的溫度越高的趨勢.目前測得的天池火山長石結構是由高溫結構隨溫度下降轉變而來,因此天池火山長石最初形成的溫度可能更高.天池火山全新世噴髮物中長石結構狀態特徵的差異可能與火山噴髮的年代、噴髮溫度有關.研究天池火山全新世噴髮物中的長石結構狀態特徵具有一定的理論和實際應用價值.
이용소묘전경화x사선연사분석수거연구천지화산천문봉부면전신세분발물중적장석표면특정화결구상태,결과현시:천문봉부면종정부흑색부암향하도암염색부암중,장석표면비교신선,개별장석유겁경미풍화,재장석과립표면요처우유침적후도불동적비정질서상물.장석위감성장석중적고투장석-고납장석계렬,특정연사봉적강도、면망d치여왜장석PDF수거기본상부,물상조성위(0r37~41,Ab63~59),표명천지화산분발물중적장석속왜장석;장석유서도개우0.045~0.089지간;η삼수개우-1.010~-1.361지간;최저결품온도위800~990℃,차정부흑색부암중장석적최저결정온도고체990℃.연구인위,유천지화산분발적년대월신,장석유서도월저,기결구상태소기록적온도월고적추세.목전측득적천지화산장석결구시유고온결구수온도하강전변이래,인차천지화산장석최초형성적온도가능경고.천지화산전신세분발물중장석결구상태특정적차이가능여화산분발적년대、분발온도유관.연구천지화산전신세분발물중적장석결구상태특정구유일정적이론화실제응용개치.
We have studied the surface features and structural state of the feldspar from the Holocene volcanic eruptive rock on the Tianfeng profile using data from observations under scanning electron microscope and analysis of x ray diffraction. On this profile black pumice appears at the top and darkgrey pumice is present at the bottom. The result shows that the feldspar in these pumice rocks has fresh surface,with slightly weathering for individual cases,and occasionally seen as non-crystalline floc of varied thickness at concaves on its grain surface. This feldspar belongs to the high sandidine-high albite series of the alkali feldspar. The intensity of its characteristic diffraction peak and its plane mesh d value are roughly consistent with the PDF data of anorthoclase. And its constitution((0r37 ~41,Ab63 ~ 59)also implies that it is anorthoelase. It has the following parameters: ordering degree 0. 045 ~ 0. 089, h value- 1. 010 ~ - 1. 361, and the lowest crystalline temperature 800 ~ 990℃ which is up to 990℃ for the black floe at the top. Our study suggests that the younger volcanic eruption at Tianchi has a lower ordering degree of feldspar and a higher temperature reflected by its structural state. Because the structure of the present feldspar at Tainchi is the result of the cooling process of the hot volcanic rock, the temperature when the feldspar was formed might be very high. The difference of structural state in this feldspar is probably associated with ages and temperatures of volcanic eruptions. The study of its features has some theoretical and applied significance.