中文摘要：

云南腾冲火山盆地深部存在岩浆囊是人们关注的问题,多方面进行了大量的研究且存在不同意见.作者此前依据低电阻异常推断出位于小空山、大空山、黑空山等火山口的下部,深13-30km范围内东西向25km,南北向30km的低电阻率的岩浆囊,其东侧为大盈江断裂.文章利用反射地震、重力、航空磁测资料进一步探讨了岩浆囊的其他地球物理特征.由于火山喷发,不仅在火山口附近形成了局部物质亏损,而且,岩浆囊本身也亏损了岩浆物质,在重力上延图中滤去了表层的火山局部负重力异常后,呈现出大空山北侧的与低阻体相对应的负重力异常,这与岩浆囊高温熔融状态含水低密度物质有密切关系.整体的重力负异常印证了低阻岩浆囊的存在.腾冲马站岩浆囊的温度为397-651℃,平均温度为524℃,其主体中心部位不可能存在磁性体.对航磁资料的处理,消除表层火山岩影响后,仍然发现有较强磁异常,其平面投影范围与低阻体相近,推断磁异常是岩浆囊顶层,在15km深度以上范围内,随着岩浆囊体温度逐步下降,当低于480℃以后会形成新的铁磁性矿物,因此,在囊体上层出现了范围与囊体相近的较强的磁性体.反射地震仅仅在浅部较清楚地观测到较连续的反射波界面,是浅部火山岩、含水层、以及花岗岩顶界面的反映.向深部反射界面很不连续推测是由于多次岩浆上涌,其喷发时间有先后,成分有差异,故岩浆囊物质的不均匀性,虽然由于含水、矿化、熔融体构成了低电阻的共性,可温度的不均匀,却又显示了不同期次岩浆成分有变化,由岩浆囊向地表的通道上,东部花岗岩下为高速,相对于较低温度的物质,在小空山、大空山和黑空山深部沿大盈江断裂带有东西两个大的隐伏花岗岩体之间是最新的火山喷发通道,具有相对低速的通道.

英文摘要：

The existence of magma pocket in the depth of Tengchong volcanic basin of Yunnan Province is a topic which hasaroused much attention. Extensive studies have been conducted from many aspects but there still exist different opinions. It waspreviously inferred by the authors based on low.resistivity anomalies that, underneath the craters of Xiaokong Mountain, DakongMountain and Heikong Mountain, there is a low . resistivity magma pocket with a depth range of 13–30 km and sizes of 25 km（from east to west） by 30 km （from south to north）, on the east of which is Dayingjiang Fault. Based on seismic reflection survey,gravity and aeromagnetic survey data, this paper further discusses other geophysical characteristics of the magma pocket. Because ofvolcanic eruption, not only local material depletion is present near the craters, but the magma pocket itself depletes magma materialas well; after the filtering of local negative gravity anomaly of surficial volcano, the gravity upward continuation map shows anegative gravity anomaly corresponding to the low.resistivity body on the north of Dakong Mountain, which is closely related to thedepletion of aqueous low . density material from magma pocket in molten state at high temperatures. The entire negative gravityanomaly corroborates the existence of low . resistivity magma pocket. The Tengchong Mazhan magma pocket has temperatures of397–651℃, with a mean value of 527℃, so magnetic body is impossibly present at the main central place of the pocket. Afterprocessing of the aeromagnetic data to eliminate the influence of surficial volcanic rock, large strong magnetic anomaly was stillfound, close to low . resistivity body in size, and it is presumed that the magnetic anomaly is at the top of the magma pocket at adepth above 15 km; as magma pocket temperature decreases gradually, new magnetic mineral will be formed below 480℃; as aresult, there appears relatively strong magnetic body at the top of the pocket with a similar range to that of the pocket. Only seismicr