HR: 0800h
AN: T51A-1330    [Abstracts]
TI: Vertical Variations of Microbial Community Structures Along the TCDP Drill Cores
AU: * Lin, L
EM: lhlin@ntu.edu.tw
AF: Department of Geosciences National Taiwan University, No.1, Sec. 4, Roosevelt Road, Taipei, 106 Taiwan
AU: Wang, P
EM: plwang@ntu.edu.tw
AF: Institute of Oceanography National Taiwan University, No.1, Sec. 4, Roosevelt Road, Taiepi, 106 Taiwan
AU: Cheng, T
EM: r92b41012@ntu.edu.tw
AF: Institute of Zoology National Taiwan University, No.1, Sec. 4, Roosevelt Road, Taipei, 106 Taiwan
AU: Yu, H
EM: ayu@ntu.edu.tw
AF: Institute of Zoology National Taiwan University, No.1, Sec. 4, Roosevelt Road, Taipei, 106 Taiwan
AU: Song, S
EM: srsong@ntu.edu.tw
AF: Department of Geosciences National Taiwan University, No.1, Sec. 4, Roosevelt Road, Taipei, 106 Taiwan
AU: Lin, W
EM: lin_weiren@ybb.ne.jp
AF: JAMSTEC, 2-15 Natsushima-cho, Yokosuka, 237-0061 Japan
AU: Yeh, E
EM: yeh@jamstec.go.jp
AF: JAMSTEC, 2-15 Natsushima-cho, Yokosuka, 237-0061 Japan
AU: Chen, C
EM: chiuwen0814@yahoo.com.tw
AF: Institute of Geophysics National Central University, No.300, Jhongda Rd., Jhongli, 324 Taiwan
AU: Wang, C
EM: wangcy@earth.ncu.edu.tw
AF: Institute of Geophysics National Central University, No.300, Jhongda Rd., Jhongli, 324 Taiwan
AB: Taiwan Chelungpu Drilling Project (TCDP) has provided an unprecedented opportunity to probe terrestrial subsurface microbial ecosystem that may have experienced constant disturbance by the arc-continent collision. The drilling penetrated through Pleistocene-Pliocene sedimentary rocks to a depth of 2000 meters below land surface (mbls). Two major fracture zones were encountered at depths of 1100 and 1750 mbls, respectively. Among 40 samples retrieved from rock formations or within fracture zones, 30 were ground to powders, enumerated with DAPI staining, inoculated to media, and screened with 16S rRNA gene variation. Cell density ranged from 10⁶ to 10⁸ cells g^-1 and did not correlate with lithology or depth. Mesophilic and thermophilic fermenters and organotrophic sulfate reducers were ubiquitously present in most samples, whereas iron reducers and methanogens appeared only in the samples retrieved from the upper (400-700 mbls) and lower depths (1800-1900 mbls). Analyses of 16S rRNA genes for samples along the depth profile revealed that microbial communities were dominated by beta-Proteobacteria for samples at depths shallower than 1300 mbls, by delta-Proteobacteria for a sample at 1675 mbls, and by Firmicutes for samples at great depths (>1900 mbls). While heterotrophic metabolisms were prevalent at shallower depths, heterotrophic metabolisms and sulfate reduction appeared to dominate at great depths (>1600 mbls). Fault gauge at 1810 mbls, however, exhibited a distinct and diverse community structure when compared with the adjacent samples. Community structure seems to be correlated with lithology, geological structure, and depth.
DE: 7230 Seismicity and tectonics (1207, 1217, 1240, 1242)
DE: 8010 Fractures and faults
DE: 8102 Continental contractional orogenic belts and inversion tectonics
DE: 8150 Plate boundary: general (3040)
SC: Tectonophysics [T]
MN: Fall Meeting 2005