Chapter 5 Discussion
5.3 The tectonic setting of the East Taiwan Ophiolite
The nature and tectonic setting of the East Taiwan Ophiolite is a topic that is still under debate (Suppe et al., 1981; Jahn, 1986; Chung and Sun, 1992; Shao, 2015).
Suppe et al. (1981) studied the stratigraphy of the Lichi formation of the Coastal Range of East Taiwan and suggested that the East Taiwan Ophiolite is a submarine scree deposit consisting of angular mafic and ultramafic plutonic blocks that formed at a ‘leaky’ transform fault offsetting (Liou et al., 1977, Suppe et al., 1981). Jahn (1986) presented geochemical and isotopic data of glassy basalts, gabbros and plagiogranites and considered that the East Taiwan Ophiolite is derived from a spreading ridge of an open ocean or marginal basin. Furthermore, Chung and Sun (1992) proposed that the East Taiwan Ophiolite formed at a slow spreading ridge environment. Shao (2015), however, compared the Hf isotope of gabbros, diorites and plagiogranites of the East Taiwan Ophiolite to similar rocks from other ophiolites and proposed that the East Taiwan Ophiolite is probably the result of upwelling of a fore-arc subduction zone.
The rock sequence of East Taiwan Ophiolite is described by previous studies (Liou et al., 1977, Liou and Ernst, 1979, Suppe et al., 1981, Chung and Sun, 1992) (Fig. 19). The red shale layers between plutonic rocks and the extrusive rocks indicate that it was exposed under the carbonate compensation depth (CCD) for a period of time, perhaps a deep ocean setting at great distance from land. If this is the case, a mid-ocean ridge setting seems to be more promising than the original ‘leaky olistostrome’ interpretation of Suppe et al. (1981). On the other hand the absence of boninite, an important mafic volcanic rock that is rich in both Mg and Si and
94
commonly found at subduction zones, suggests the East Taiwan Ophiolite is unlikely to related to a suprasubduction zone (SSZ) type ophiolite or to any subduction-related setting. The relatively high εNd(T) values of the gabbroic ETO ophiolitic rocks (i.e. >
+9) also suggests that the fore-arc subduction interpretation is vulnerable
The bulk rock geochemistry and mineral geochemistry of peridotites can be used to distinguish between different tectonic settings (Dick and Bullen, 1984;
Bonatii and Michael, 1989; Arai, 1992, 1994; Kamenetsky et al., 2001; Hebert et al., 2003). Some major and trace elements such as Mg, Cr and Al content, that are relatively immobile during serpentinization, can retain their original concentration or ratio and thus be used for interpreting the tectonic setting. Dick and Bullen (1984) compared a wide range of abyssal and Alpine-type spinel bearing peridotite and categorized the rocks by Cr# as an indicator of the degree of the depletion of the mantle source. Bonatti and Michael (1989) have demonstrated that whole rock Mg#
and Al content, and Cr# of spinel can be effective in distinguishing peridotites derived at ridge settings, passive margin settings, pre-oceanic rift and oceanic trench settings. Arai (1994) reviewed and discussed the Fo-Cr# trends in peridotites in different conditions (e.g. ocean-floor, back-arc basin, fore-arc, oceanic hot-spot, island arcs, subcontinental, subcratonic peridotite).
In this study the classification scheme of Bonatti and Michael (1989) is applied to the bulk rock geochemistry and spinel chemistry of the ETO peridotites.
The Mg# of the peridotites from this study and previous work range between 90 and 93 which are typical of a mid-ocean ridge setting like the North Atlantic (Fig. 20).
The bulk rock aluminum content of the serpentinized peridotites, although somewhat
95
depleted, is consistent with the Mg# and an oceanic ridge setting (Fig. 21). The Cr#
of spinel is a particularly robust indicator for the tectonic setting of peridotites because it is relatively unaffected by hydrothermal conditions commonly experience by oceanic peridotites (Dick and Bullen, 1984; Bonatii and Michael, 1989; Arai, 1994). The mineral chemistry of the spinels as shown in Figure 22 is consistent with the previous results of bulk aluminum and Mg#. Therefore the peridotite whole rock and spinel geochemistry indicate that the ETO was formed at a mid-ocean ridge setting which is consistent with the interpretations of Liou et al. (1977) and Jahn (1986). However, it is uncertain if the ETO was a slow-spreading ridge as proposed by Chung and Sun (1992).
.
96
Figure 19. Rock sequence of East Taiwan Ophiolite (revised from Liou, 1977).
97
Figure 20. Whole rock Mg number (revised from Bonatti, 1988).
98
Figure 21. Whole rock aluminum content (revised from Bonatti, 1988).
99
Figure 22. Spinel chrome number (revised from Bonatti, 1988).
100 5.4 Implications for the South China Sea
The East Taiwan Ophiolite, representing the rock sequence of the oceanic crust and uppermost mantle, is considered to be a preserved remnant of oceanic crust from either the South China Sea (Liou et al. 1977; Suppe and Liou, 1979; Liou, 1979;
Suppe et al., 1981; Jahn, 1986; Chung and Sun, 1992). The spinel chemistry, Nd isotopes and whole rock Mg# and Al2O3 content from the peridotites indicates that the rocks were likely formed at a Mid-Ocean Ridge setting. Therefore the ETO is more likely to be a remnant of the South China Sea because there was no other active spreading center located within the region during the Miocene.
The tectonic development of the South China Sea is a highly debated subject.
The duration of spreading, in particular, is a one of a number of issues that has yet to be fully resolved. Originally Taylor and Hayes (1980, 1983) proposed a magnetic anomaly chronology for South China Sea basin which is still widely accepted (11 to 5d, Taylor and Hayes, 1980, 1983; revised to 11 to 5c, Briais et al., 1993). They identified an E-W oriented spreading center between the Macclesfield Bank and Reed Bank (Fig. 23), where the symmetric anomalies 5d through 6c have been modeled to the north and south. Beyond the Macclesfield Bank and close to the South China were anomalies 7 to 11. The spreading ridge has a conjunction from NW-SE direction to E-W direction, and it is said to be a result of a ridge jump that occurred at anomaly 7 (~24.8-25 Ma) (Brais et al. 1993; Barckhausen and Roeser, 2004; Barckhausen et al. 2014; Li et al. 2014)
101
Figure 23. South China Sea spreading ridge and magnetic anomalies (revised from Taylor and Hayes, 1983; Briais et al., 1993).
102
Currently the duration of tectonic/magmatic activity of the South China Sea is widely accepted to be 32-15.5 Ma (Taylor and Hayes, 1980, 1983; Briais et al., 1993), however Barckhausen and Roeser (2004) suggested the South China Sea was active for only 12 Ma from 32 to 20.5 Ma, about 4-5 million years earlier than previous researches. Barckhausen et al. (2014) supported the interpretation by proposing a new spreading rate of the South China Sea before and after the ridge jump, suggesting a 56 mm/yr rate in the early stages and increasing to 72 mm/yr after the ridge jump in the central and NE sub-basin, and increasing to 80 mm/yr in the SW sub-basin. Li et al. (2014), based on the new deep tow magnetic anomalies and IODP Expedition 349 core, pulled back the age of spreading to 33-15 Ma and suggested the ridge jump occurred at ~23.6 Ma. Li et al. (2014) also disagreed the spreading rate that proposed by Barckhausen et al. (2014) as they pointing out that the spreading rate decreased from ~50 mm/yr to ~35 mm/yr at the later stage of the spreading instead of increasing to 72 mm/yr after the ridge jump. Chang et al. (2015) also commented on Barckhausen’s saying that Barckhausen and Roeser (2004) and Barckhausen et al. (2014) had neglected the radioactive age dating (Jahn, 1986) and nanofossil assemblage from the ETO (Hunag et al., 1979) and re-announced the slow-spreading ridge is the more plausible ocean spreading motion of the South China Sea.
If the East Taiwan Ophiolite is really a remnant of the South China Sea, the new age result dated in this study and by Shao (2015) suggest that magmatism and thus extensional tectonism of the South China Sea lasted until at least the mid Miocene (i.e. ~14 Ma) and is ~1.5 million years later than the accepted age now.
103
Jahn (1986) predicted that the East Taiwan Ophiolite had a life span of < 10 Ma based on a spreading rate of ~10 cm/yr indicating that it traveled a maximum distance of 1000 km. However, the ~10 cm/yr rate may be too fast and the ~1000 km distance may be too large but a rate of 5-8 cm/yr and maximum distance of 500 km to 800 km may be suitable (Ben-Avraham and Uyeda, 1973; Hall et al., 1995; Teng and Lin, 2004). From previous studies, the collision of the Luzon Arc with the Eurasian continental margin took place at ~4-5 Ma. (Jahn, 1986; Teng, 1987, 1990, 2007). Thus the duration of the displacement of East Taiwan Ophiolite from the ridge to where it is now would take ~ 10 million years (i.e. ~14.3 Ma to ~4.5 Ma). Based on a 5-8 cm/yr moving rate and 10 million years duration, the possible displacement distance is between 500 km and 800 km, which are drawn as dashed circles in figure 24. Figure 24 shows the estimated part of the South China Sea spreading ridge (dashed line in figure 24) that was consumed beneath the Manila trench (Lee and Lawver, 1995; Zhu et al., 2004). The orange zone is the probable area that the spreading ridge would be and also as the possible place that formed the East Taiwan Ophiolite. Therefore as the Luzon arc collided with proto-Taiwan it likely brought fragments of the youngest portion of the South China Sea spreading center with. The oceanic fragments were accreted to Taiwan and become known as the ETO.
Table 6. Various age estimates of the South China Sea (SCS) basin from previous studies.
Authors Ages (Ma) Study Area Year of Publication Data used
Taylor and Hayes 32 – 17 East sub-basin 1980, 1983 Magnetic anomaly
Briais et al. 32 – 15.5 Central SCS basin 1993 Magnetic anomaly
Barckhausen and Roeser
31 – 20.5 Central SCS basin 2004, 2014 Magnetic anomaly
Hsu et al. 37 – 15 Central SCS basin &
NE SCS sub-basin
2004 Magnetic anomaly
Li et al. 33 – 15
33 – 16
NE SCS sub-basin SW SCS sub-basin
2014 Magnetic anomaly
104
Figure 24. Tectonic development of the East Taiwan Ophiolite at 15 Ma. (revised from Lee and Lawver, 1995)
105
106
Chapter 6
Conclusion
The new whole rock major and trace elemental and isotopic geochemistry, mineral chemistry and zircon U/Pb age date presented here and data from previously published works suggest that the East Taiwan Ophiolite has characteristics that are typically found in the oceanic crust that formed at a spreading ridge of an ocean basin.
The Cr# of spinel from the peridotite and bulk rock Al and Mg content are consistent with the oceanic ridge setting. The relatively high 143Nd/144Nd isotope ratio and the N-MORB-like REE pattern of the ETO gabbro also suggest a mid-ocean ridge environment. The mid Miocene zircon U/Pb age of the ETO gabbro is about ~1 Ma younger than the last magnetic anomaly of South China Sea (i.e. 5c) and suggests the tectonomagmatic activity was still ongoing at that time. The age result and assuming a 5-8 cm/yr moving rate, the possible emplacement distance is between 500 and 800 km which corresponds to an area of ~100 000 km2.
107
References
Anonymous, 1972, Penrose Field Conference on Ophiolites, Penrose 1972, v. 17, Geotimes, p. 24-25.
Arai, S., 1992, Chemistry of cheromian spinel in volcanic rocks as a potential guide to magma chemistry, Mineralogical Magazine, v. 56, p. 173-184.
Arai, S., 1994, Characterization of spinel peridotites by olivine-spinel compositional relationships: Review and interpretation, Chemical Geology, v. 113, p. 191-204.
Barckhausen, U., Engels, M., Franke, D., Ladage, S., and Pubellier, M., 2014, Evolution of the South China Sea: Revised ages for breakup and seafloor spreading, Marine and Petroleum Geology, v. 58, p. 599-611.
Barckhausen, U., and Roeser, H. A., 2004, Seafloor spreading anomalies in the South China Sea revisited, in Clift, P., Kuhnt, W., Wang, P., and Hayes, D. E., eds., Continent-Ocean Interactions Within East Asian Marginal Seas, American Geophysical Union, v. 149, p. 121-125.
Ben-Avraham, Z., and Uyeda, S., 1973, The evolution of the China Basin and the Mesozoic paleogeography of Borneo, Earth and Planetary Science Letters, v.
18, p. 365-376.
Biq, C. C., 1969, Role of graviational gliding in Taiwan tectogenesis, Bulletin of the geological survey of Taiwan, v. 20, p. 1-40.
Bodinier, J. L., and Godard, M., 2003, Orogenic, ophiolitic, and abyssal peridotites, in Holland, H. D., and Turekian, K. K., eds., Treatise on Geochemistry, Elsevier Ltd., p. 103-170.
Bodinier, J. L., Menzies, M. A., and Thirlwall, M. F., 1991, Continental to oceanic mantle transition - REE and Sr-Nd isotope geochemistry of the Lanzo Lherzolite Massif, in Menzies, M. A., Dupuy, C., and Nicolas, A., eds., Orogenic lherzolites and mantle processes, Oxford University Press.
Bonatti, E., Honnorez, J., and Ferrara, G., 1970, Equatorial Mid-Atlantic ridges:
Petrologic and Sr isotopic evidence for an alpine-type rock assemblage, Earth and Planetary Science Letters, v. 9, no. 3, p. 247-256.
Bonatti, E., and Micheal, P. J., 1989, Mantle peridotite from continental rifts to ocean basins to subduction zones, Earth and Planetary Science Letters, v. 91, p. 297-311.
Bowin, C., Lu, R. S., Lee, C. S., and Schouten, H., 1978, Plate convergence and accretion in the Taiwan-Luzon region, American Association of Petroleum Geologists Bulletin, v. 62, p. 1645-1672.
Briais, A., Patriat, P., and Tapponnier, P., 1993, Updated interpretation of magnetic anomalies and seafloor spreading stages in the South China Sea: Implications for the Tertiary tectonics of Southeast Asia, Journal of Geophysical Research, v. 98, no. B4, p. 6299-6328.
Brongniart, A., 1827, Classification et caracteres mineralogiques des roches homogenes et heterogenes, Paris, France, F. G. Levrault.
Chai, B. H. T., 1972, Structure and tectonic evolution of Taiwan, American Journal of Science, v. 272, p. 389-422.
108
Chang, J. H., Lee, T. Y., Hsu, H. H., Liu, C. S., Comment on Barckhausen et al., 2014 – Evolution of the South China Sea: Revised ages for breakup and seafloor spreading, Marine and Petroleum Geology (2014)
Chang, L. S., 1975, Biostratigraphy of Taiwan, Geology and Paleontology of Southeast Asia, v. 15, p. 337-361.
Chen, C. H., Lo, H. J., and Juan, V. C., 1976, Olivine in Taiwanite, Proceedings of the Geological Society of China, v. 19, p. 98-106.
Chen, W. S., Huang, M. T., and Liu, T. K., 1991, Neotectonic significance of the Chimei Fault in the Coastal Range, eastern Taiwan, Proceedings of the Geological Society of China, v. 34, no. 1, p. 43-56.
Chi, W. R., Namson, J., and Suppe, J., 1981, Straigraphic record of plate interactions in the Coastal Range of eastern Taiwan, Memoir of the Geological Society of China, v. 4, p. 155-194.
Chou, C. L., Lo, H. J., Chen, J. H., and Juan, V. C., 1978, Rare earth element and isotopic geochemistry of Kuanshan igneous complex, Taiwan, Proceedings of the Geological Society of China, v. 21, p. 13-24.
Chung, S. L., and Sun, S. S., 1992, A new genetic model for the East Taiwan Ophiolite and its implications for Dupal domains in the Northern Hemisphere, Earth and Planetary Science Letters, v. 109, p. 133-145.
Coleman, R. G., 1977, Ophiolites - Ancient Oceanic Lithosphere?, Germany, Springer-Verlag Berlin, Heidelberg.
Cui, X. J., Xia, B., Zhang, Y. H., Liu, B. M., Wang, R., and Yan, Y., 2005, A numerical modeling study on the "asthenosphere upwelling" of South China Sea, Geotectonica et Metallogenia, v. 29, no. 3, p. 334-338.
Dick, H. J. B., and Bullen, T., 1984, Chromian spinel as a petrogenetic indicator in abyssal and alpine-type peridotites and spatially associated lavas, Contributions to Mineralogy and Petrology, v. 86, p. 54-76.
Dilek, Y., 2003, Ophiolite concept and its evolution, Geological society of America Special Papers, v. 373, p. 1-16.
Dilek, Y., and Furnes, H., 2009, Structure and geochemistry of Tethyan ophiolites and their petrogenesis in subduction rollback systems, Lithos, v. 113, p. 1-20.
Dilek, Y., and Furnes, H., 2011, Ophiolite genesis and global tectonics: Geochemical and tectonic fingerprinting of ancient oceanic lithosphere, Geological Society of America Bulletin, v. 123, no. 3-4, p. 387-411.
Dilek, Y., and Polat, A., 2008, Suprasubduction zone ophilites and Archean tectonics, Geology, v. 36, p. 431-432.
Downes, H., Bodinier, J. L., Thirlwall, M. F., Lorand, J. P., and Fabries, J., 1991, REE and Sr-Nd isotopic geochemistry of Eastern Pyrenean Peridotite Massifs:
Sub-continental lithospheric mantle modified by continental magmatism, Journal of Petrology, Special Lherzolites Issue, p. 97-115.
Ernst, W. G., 2005, Alpine and Pacific styles of Phanerozoic mountain building:
subduction-zone petrogenesis of continental crust, Terra Nova, v. 17, no. 2, p. 165-188.
Flower, M., Tamaki, K., and Hoang, N., 1998, Mantle extrusion: A model for dispersed volcanism and DUPAL-like asthenosphere in East Asia and the western Pacific, in Flower, M. F. J., Chung, S. L., Lo, C. H., and Lee, T. Y.,
109
eds., Mantle Dynamics and Plate Interactions in East Asia, American Geophysical Union, v. 27, p. 67-88.
Furnes, H., de Wit, M., and Dilek, Y., 2014, Four billion years of ophiolites reveal secular trends in oceanic crust formation, Geoscience Frontiers, v. 5, no. 4, p.
571-603.
Gao, J. Y., Wang, J., Yang, C. G., Zhang, T., and Tan, Y. H., 2008, Discussion on back-arc rifting tectonics and its geodynamic regime of the Okinawa Trough, Progress in Geophysics, v. 23, no. 4, p. 1001-1012.
Gruau, G., Bernard-Griffiths, J., and Lecuyer, C., 1998, The origin of U-Shaped rare earth patterns in ophiolite peridotites: Assessing the role of secondary alteration and melt/rock reaction., Geochimica et Cosmochimica Acta, v. 62, no. 21/22, p. 3545-3560.
Hall, R., Ali, J. R., Anderson, C. D., and Baker, S. J., 1995, Origin and motion history of the Philippine Sea Plate, Tectonophysics, v. 251, p. 229-250.
Hayes, D. E., 1988, Age‐depth relationship and depth anomalies in the Southeast Indian and South Atlantic Ocean, Journal of Geophysical Research, v. 93.
Hebert, R., Hout, F., Wang, C. S., and Liu, Z. F., 2003, Yarlung Zanboo ophiolites (southern Tibet) revisited: Geodynamic implications from the mineral record, in Dilek, Y., and Robinson, P. T., eds., Ophiolites in Earth History, Geological Society of London Special Publications, v. 218, p. 165-190.
Hess, H. H., 1955, Crust of the Earth, Geological Society of America Special Papers, v. 62, p. 391-407.
Hess, H. H., 1962, History of Ocean Basins, in Engel, A. E. J., James, H. L., and Leonard, B. F., eds., Petrologic studies: a volume in honor of A. F.
Buddington. Boulder, Geological Society of America, p. 599-620.
Holloway, N. H., 1982, North Palawan Block, Philippines - Its relation to Asian Mainland and role in the evolution of South China Sea, American Association of Petroleum Geologists Bulletin, v. 66, p. 1355-1383.
Hsu, S. K., Yeh, Y. C., Doo, W. B., and Tsai, C. H., 2004, New bathymetry and magnetic lineations identifications in the northernmost South China Sea and their tectonic implications, Marine Geophysical Researches, v. 25, p. 29-44.
Hsu, T. L., 1956, Geology of the Coastal Range, eastern Taiwan, Bulletin of the geological survey of Taiwan, v. 8, p. 39-63.
Hsu, T. L., 1976, The Lichi mélange in the Coastal Range framework, Bulletin of the geological survey of Taiwan, v. 25, p. 87-96.
Huang, C. Y., Yuan, P. B., and Tsao, S. J., 2006, Temporal and spatial records of active arc-continent collision in Taiwan: A synthesis, Geological Society of America Bulletin, v. 118, no. 3-4, p. 274-288.
Huang, T. C., Chen, M. P., and Chi, W. R., 1979, Calcareous nanofossils from the red shale of the ophiolite-mélange complex, eastern Taiwan, Memoir of the Geological Society of China, v. 3, p. 131-138.
Ishiwatari, A., 1991, Ophiolites in the Japanese islands: Typical segment of the circum-Pacific multiple ophiolite belts, Episodes, v. 14, p. 274-279.
Ishiwatari, A., 1994, Circum-Pacific Phanerozoic multiple ophiolite belts, in Proceedings 29th International Geological Congress, Tokyo, Japan, 1994, VSP, p. 7-28.
110
Jahn, B. M., 1986, Mid-ocean ridge or marginal basin origin of the East Taiwan Ophiolite_ chemical and istopic evidence, Contributions to Mineralogy and Petrology, v. 92, p. 194-206.
Juan, V. C., Lo, H. J., and Chen, C. H., 1976, Crystallization-differentiation of Taiwanite, Proceedings of the Geological Society of China, v. 19, p. 87-97.
Juan, V. C., Tai, H., and Chang, F. H., 1953, Taiwanite, a new basaltic rocks of east Coastal Range, Taiwan and its bearing on the parental magma types, ACTA Geologica Taiwanica v. 5, p. 1-25.
Kamenetsky, V. S., Crawford, A. J., and Meffre, S., 2001, Factors controlling chemistry of magmatic spinel: An empirical study of associated olivine, Cr-spinel and melt inclusions from primitive rocks, Journal of Petrology, v. 42, no. 4, p. 655-671.
Kao, H., Shen, S. J., and Ma, K. F., 1998, Transition from oblique subduction to collision: earthquakes in the southernmost Ryukyu Arc - Taiwan region, Journal of Geophysical Research, v. 103, p. 7211-7229.
Kapsiotis, A. N., 2013, Origin of mantle peridotites from the Vourinos Ophiolite Complex, Greece, as deduced from Cr-Spinel morphological and chemical variations, Journal of Geosciences, v. 58, p. 217-231.
Karig, D. E., 1971, Origin and development of marginal basins in the western Pacific, Journal of Geophysical Research, v. 76, no. 11, p. 2542-2561.
Kempton, P. D., and Stephens, C. J., 1997, Petrology and geochemistry of nodular websterite inclusions in harzburgite, hole 920D, Proceedings of the Ocean Drilling Program, Scientific Results, v. 153, p. 321-331.
Lee, C. T., and Wang, Y., 1987, Paleostress change due to the Pliocene-Quaternary arc-continent collision, Memoir of the Geological Society of China, v. 9, p.
63-86.
Lee, T. Y., and Lawver, L. A., 1995, Cenozoic plate reconstruction of Southeast Asia, Tectonophysics, v. 251, p. 85-138. structures of the South China Sea constrained by deep tow magnetic surveys and IODP expedition 349, Geochemistry, Geophysics, Geosystems, v. 15, no.
12, p. 4958-4983.
Li, C. F., Zhou, Z. Y., Li, J., Hao, H., and Geng, J., 2007, Structures of the northeastrnmost South China Sea continental margin and ocean basin:
geophysical constraints and tectonic implications, Marine Geophysical Researches, v. 28, p. 59-79.
Liou, J. G., 1979, Zeolite facies metamorphism of basaltic rocks from the East Taiwan Ophiolite, American Mineralogist, v. 64, p. 1-14.
Liou, J. G., and Ernst, W. G., 1979, Oceanic ridge metamorphism of the East Taiwan Ophiolite, Contributions to Mineralogy and Petrology, v. 68, p. 335-348.
111
Liou, J. G., Lan, C. Y., Suppe, J., and Ernst, W. G., 1977, The East Taiwan Ophiolite - Its occurrence, petrology, metamorphism and tectonic setting, Taipei, Taiwan, Mining research and service organization industrial technology research institute.
Ludwig, K. R., 2003, User's Manual for Isoplot/Ex, version 3.0, a geochronological toolkit for Microsoft Excel Berkeley Geochronology Center Special Publication, Berkeley Geochronology Center, v. 4.
Ludwig, W. J., 1970, The Manila Trench and west Luzon Trough III. Seismic-refraction measurements, Deep-Sea Research, v. 17, p. 553-571.
Mandur, M. M. M., 2009, Calcareous nannoplankton biostratigraphy of the Lower and Middle Miocene of the Gulf of Suez, Egypt, Australian Journal of Basic and Applied Sciences, v. 3, no. 3, p. 2209-2303.
Marzouk, A., 2009, Nannofossil biostratigraphy of Miocene sections from two wells in the Gulf of Suez, Egypt, Palaontologie, Stratigraphie, Fazies, v. 17, p. 101-127.
McDonough, W. F., and Sun, S. S., 1995, The composition of the earth, Chemical
McDonough, W. F., and Sun, S. S., 1995, The composition of the earth, Chemical