負(fù)責(zé)人：何玉梅 研究員 ymhe@mail.iggcas.ac.cn
2015年，中國科學(xué)院地質(zhì)與地球物理研究所與緬甸地球科學(xué)學(xué)會聯(lián)合，在緬甸造山帶實施了中緬地球物理觀測項目一期，以探索緬甸下方的深層結(jié)構(gòu)，研究陸陸碰撞后的大陸俯沖動力學(xué)。
在該項目的支持下，從2016年6月至2018年2月，我們在緬甸部署了第一個大尺度流動地震臺陣。該地震臺陣包含71個臨時臺站，從西到東覆蓋緬甸中部（21.6°N-23.9°N和93.1°E-97.3°E）。該臺陣由一個東西走向的線性子臺陣和二維主干網(wǎng)絡(luò)組成。線性子臺陣長400 km，穿過緬甸的主要構(gòu)造單元。具體從Rezua的西部，印緬山脈的緬甸-印度邊界，往東穿過中央盆地和實皆斷層，最后到達(dá)撣邦高原的Hsipaw。總共部署了38個臺站，每個臺站之間間隔10-15公里。二維主干網(wǎng)由33個臺站組成，臺站間距30-50 km，覆蓋印緬山脈和中央盆地的250km×320km區(qū)域 （圖1，圖2，圖3）。
二維主干臺陣的所有臺站和東西走向線性子臺陣中的13個臺站均配備了Nanometrics Trillium 120PA寬頻帶地震計，帶寬從50 Hz到120 s，而線性子臺陣的其他臺站配備了Guralp CMG-3ESP寬頻帶地震計，頻率從50 Hz至30/60 s。所有臺站都配備了REF TEK 130數(shù)字記錄儀?？紤]到緬甸農(nóng)村的電力短缺，每個臺站都配備了兩個60W的太陽能電池板和一個70Ah或100Ah的電池，這具體取決于雨季的道路情況（圖4）。地震臺陣實驗室的技術(shù)人員、中國科學(xué)院地質(zhì)與地球物理研究所的研究人員和緬甸地球科學(xué)學(xué)會的同事每3個月收集一次地震數(shù)據(jù)。在18個月的觀測期間，共收集了457G的連續(xù)數(shù)據(jù)，這些數(shù)據(jù)清楚地記錄了低噪聲條件下的地震。
圖1 流動臺站分布（紅色三角）
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圖2 臺站選址
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圖3 中緬地球物理專家合作建設(shè)項目的第一個臺站M28臺
圖4緬甸野外臺站布設(shè)
項目相關(guān)已發(fā)表文章:
1.Yumei He, Tianyu Zheng*, Yinshuang Ai, Guangbing Hou, Qi-Fu Chen (2018), Growth of the lower continental crust via the relamination of arc magma, Tectonophysics, 724-725, 42-50.
2. Yi Wang, Yumei He*, Gang Lu, Lianxing Wen (2020), Seismic, thermal and compositional structures of the stagnant slab in the mantle transition zone beneath southeastern China, Tectonophysics, 775, 228208.
3. Tianyu Zheng, Yumei He*, Lin Ding, Mingming Jiang, Yinshuang Ai, Chit Thet Mon, Guangbing Hou, Kyaing Sein, Myo Thant (2020), Direct structural evidence of Indian continental subduction beneath Myanmar, Nature Communications. 11:1944, Doi: 10.1038/s41467-020-15746-3. The seismic receiver functions for this study can be downloaded via ftp://159.226.119.161/data/CMGSMO-1/RF_mainprofile.
4.Chit Thet Mon, Xuan Gong, Yun Wen, Mingming Jiang, Qi-Fu Chen, Miao Zhang, Guangbing Hou, Myo Thant, Kyaing Sein, Yumei He* (2020), Insight into major active faults in Central Myanmar and the related geodynamic sources, Geophysical Research Letters, 47, e2019GL086236. Doi:
10.1029/2019GL086236. Earthquake waveforms for this study can be downloaded via ftp://
159.226.119.161/data/CMGSMO-1/Myanmar_Reloc_Focmec.
5.Yuan Ling, Tianyu Zheng*, Yumei He, Guangbing Hou (2020), Response of crustal structure to Tibetan Plateau growth and Neo-Tethys evolution in Yunnan Province, China. Tectonophysics, 797, 228661.
6.Yiming Bai, Xiaohui Yuan, Yumei He, Guangbing Hou, Myo Thant, Kyaing Sein, Yinshuang Ai*(2020), Mantle transition zone structure beneath Myanmar and its geodynamic implications, Geochemistry Geophysics Geosystems (G3), e2020GC009262. Doi: 10.1029/2020GC009262. Receiver function data used in this study can be downloaded via http://www.dx.doi.org/10.12197/2020GA018.
7.Guangli Zhang, Yumei He*, Yinshuang Ai*, Mingming Jiang, Chit Thet Mon, Guangbin Hou, Myo Thant, Kyaing Sein (2021), Subducted Indian continental lithosphere and related volcanism beneath Myanmar: Constraints from local earthquake tomography. Earth and Planetary Science Letters, 567:116987. Doi: 10.1016/j.epsl.2021.116987.
8.Enbo Fan, Yumei He, Yinshuang Ai*, Steve Gao*, Kelly H. Liu, Mingming Jiang, Guangbing Hou, Chit Thet Mon, Myo Thant, Kyaing Sein (2021), Seismic anisotropy and mantle flow constrained by shear wave splitting in central Myanmar. Journal of Geophysical Research, Doi: 10.1029/2021JB022144. The CMGSMO teleseismic waveform data, local earthquakes waveform data, and receiver function data used in this study can be accessed from http://www.geophys.ac.cn/ArticleDataInfo.asp?MetaI d=309.
9.Yiming Bai, Yumei He, Xiaohui Yuan, Frederik Tilmann, Yinshuang Ai*, Mingming Jiang, Guangbing Hou, Chit Thet Mon, Myo Thant, Kyaing Sein (2021), Seismic structure across central Myanmar from joint inversion of Receiver Functions and Rayleigh wave dispersion. Tectonophysics, 818, 229068. Data related to this paper may be requested from the authors.
10.Shun Yang, Xiaofeng Liang, Mingming Jiang*, Lin Chen, Yumei He*, Chit Thet Mon, Guangbing Hou, Myo Thant, Kyaing Sein, Bo Wan (2022), Slab remnants beneath the Myanmar terrane evidencing double subduction of the Neo-Tethyan Ocean. Science Advances, 8(34), eabo1027. Doi: 10.1126/sciadv.abo1027. The CMGSMO seismic waveform data used in this study can be accessed from http://doi.org/10.12197/2022GA010.