在太古宙地盾發現的酸性侵入岩，英雲閃長岩-奧長花崗岩-花崗閃長岩套 (TTG)，是目前發現最早的大陸地殼。地球上長英質大陸地殼的成因是否與板塊運動有直接關係仍存在爭議。當代認為大陸地殼的成因主要與上部地函的含水礦物脫水所導致的部份熔融有關，可形成於隱沒帶或地殼增厚區域。已知地球上部地函存在含水礦物，因此很難討論在無水環境下長英質岩石的成因。
在太陽系的類地行星中，金星的大小與質量與地球相近，且金星表面也具有高地地形，如Ishtar Terra和Aphrodite Terra，但目前沒有證據表明金星在她的演化歷史中曾經或目前仍有板塊構造運動，而且金星表面沒有水。而根據太空時期多次觀測任務的結果，顯示在Venera 14登陸金星地點的表面岩石，其化學成分與地球上綠岩帶的橄欖矽質玄武岩(olivine tholeiite)相近。在缺乏板塊運動與水的金星上，是否存在玄武岩可以產生部分熔融的環境，其產物是否屬於酸性岩漿，就成為本研究探討的議題，並且也試圖為地球太古宙的研究提供一些新的觀點。
本研究利用金星探測任務測得的金星玄武岩化學成分調配起始材料，並參考學者所模擬的金星溫度梯度模型，進行一系列高溫高壓實驗，最後發現在1.5GPa 1090oC、2GPa 1080oC、2GPa 1285oC時，金星玄武岩開始有部分熔融的現象，在2GPa 1285oC時其岩漿的成分為SiO2 = 72.99 wt％，TiO2 = 0.41 wt％，Al2O3 = 15.80 wt％，FeO = 1.45 wt％，MnO = 0.08 wt％ ，MgO ＝ 0.74 wt％，CaO ＝ 3.72 wt％，Na2O ＝ 2.86 wt％，和K2O ＝ 1.95 wt％。組成類似於地球太古宙克拉通的低鉀英雲閃長岩/奧長花崗岩。儘管實驗持續時間相對較短（〜24小時），並且可能尚未達到系統平衡，但結果表明，在Venera 14著陸點所測得的金星表面岩石化學成分相似的玄武岩成分，確實有可能產生與地球太古宙TTG岩套相近的熔融岩漿，進而表示金星上有可能存在由酸性火成岩所構成的地殼。這個結果也顯示了在金星或地球太古宙較高的溫度梯度下，就已經提供了玄武岩可以產生部分熔融的高溫環境，而不需要板塊運動或水的輔助，亦即TTG的生成有可能不需要板塊運動或水的介入。

The silicic intrusive rock suite tonalite-trondhjemite-granodiorite (TTG) unearthed in the Archaean craton is known the earliest continental crust so far. The formation of the felsic continental crust on the Earth is directly related to plate tectonic is still in debate. The continental crust is mainly generated from the partial melting which is associated with the dehydration of hydrous minerals in the upper mantle during the process of subduction or crustal thickening. It is known that hydrous minerals exist in the upper mantle of the Earth, so it is difficult to discuss the origin of felsic rocks in an anhydrous condition.
Among the terrestrial planets in the solar system, Venus is similar to the Earth in size and mass, and the surface of Venus also has high terrain, such as Ishtar Terra and Aphrodite Terra. However, there is no evidence that Venus has been or currently has plates tectonic in her evolutionary history, and there is no water on Venus surface. According to the results of multiple observation missions during the space age, the composition of basalt measured at the Venera 14 landing site has a chemical composition indistinguishable from olivine tholeiite of terrestrial greenstone belts. So, on Venus, which lacks plate tectonic and water, whether there is a condition on Venus that allows basalt to partially melt, whether the product is silicic melts, has become the subject of this study, and may also provide some new opinions for Archean Earth research.
In this study, we used the chemical composition of the Venus basalt estimated from the Venus exploration mission to prepare the starting materials and referred to the Venus thermal gradient model simulated by previous study and conducted a series of high-temperature and high-pressure experiments. Finally, it was found that at 1.5GPa 1090oC, 2GPa 1080oC, 2GPa 1285oC, the Venusian basalt began to partially melt. The results of the experiments show the average chemical composition of the silicic glass at 2 GPa and 1285oC is: SiO2 = 72.99 wt%, TiO2 = 0.41 wt%, Al2O3 = 15.80 wt%, FeO = 1.45 wt%, MnO = 0.08 wt%, MgO = 0.74 wt%, CaO = 3.72 wt%, Na2O = 2.86 wt%, and K2O = 1.95 wt%. The composition is similar to the low potassium tonalitic/trondhjemitic rocks of terrestrial Archean cratons. Although the duration of the experiment is relatively short (~24 hours) and may not have achieved equilibrium, the result shows that the basalt composition of the surface of Venus measured at the Venera 14 landing site is similar to that of the Earth. The similar melted magma of the Archean TTG suite further indicates that there may be a crust composed of silicic igneous rocks on Venus. This result also shows that under the higher thermal gradient of Venus or Archaean Earth, a high temperature condition where basalt can produce partial melting is provided without the assistance of plate tectonic or water, that is, the generation of TTG may not require plate tectonic or the intervention of water.

Anderson, F. S., and Smrekar, S. E. Global mapping of crustal and lithospheric thickness on Venus. Journal of Geophysical Research-Planets, 111(E8). (2006).
Armann, M., and Tackley, P. J. Simulating the thermochemical magmatic and tectonic evolution of Venus's mantle and lithosphere: Two-dimensional models. Journal of Geophysical Research-Planets, 117. (2012).
Barker, F. Trondhjemite: definition, environment and hypotheses of origin. In Developments in petrology (Vol. 6, pp. 1-12). Elsevier. (1979).
Bottke, W., Vokrouhlicky, D., Ghent, B., Mazrouei, S., Robbins, S., and Marchi, S. On asteroid impacts, crater scaling laws, and a proposed younger surface age for Venus. Paper presented at the Lunar and Planetary Science Conference. (2016).
Bowring, S. A., and Williams, I. S. Priscoan (4.00-4.03 Ga) orthogneisses from northwestern Canada. Contributions to Mineralogy and Petrology, 134(1), 3-16. (1999).
Brown, M. Granite: From genesis to emplacement. Geological Society of America Bulletin, 125(7-8), 1079-1113. (2013).
Campbell, I. H., and Taylor, S. R. No Water, No Granites - No Oceans, No Continents. Geophysical Research Letters, 10(11), 1061-1064. (1983).
Clark Jr, S. P., and Ringwood, A. Density distribution and constitution of the mantle. Reviews of Geophysics, 2(1), 35-88. (1964).
Condie, K. C., and Pease, V. When did plate tectonics begin on planet Earth? (Vol. 440). Geological Society of America. (2008).
Crameri, F., and Tackley, P. J. Subduction initiation from a stagnant lid and global overturn: new insights from numerical models with a free surface. Progress in Earth and Planetary Science, 3:30. (2016).
Davaille, A., and Smrekar, S. The importance of plumes to trigger subduction of a sluggish lid: examples from laboratory experiments and planets. Paper presented at the EGU General Assembly Conference Abstracts. (2014).
Davaille, A., Smrekar, S. E., and Tomlinson, S. Experimental and observational evidence for plume-induced subduction on Venus. Nature Geoscience, 10(5), 349-355. (2017).
Deer, W. A., Howie, R. A., and Zussman, J. Rock-forming Minerals: Vol. 4: Framework Silicates. Longman. (1963).
Defant, M. J., and Drummond, M. S. Derivation of Some Modern Arc Magmas by Melting of Young Subducted Lithosphere. Nature, 347(6294), 662-665. (1990).
Drummond, M. S., Defant, M. J., and Kepezhinskas, P. K. Petrogenesis of slab-derived trondhjemite-tonalite-dacite/adakite magmas. Transactions of the Royal Society of Edinburgh-Earth Sciences, 87, 205-215. (1996).
Ernst, W. G., Sleep, N. H., and Tsujimori, T. Plate-tectonic evolution of the Earth: bottom-up and top-down mantle circulation. Canadian Journal of Earth Sciences, 53(11), 1103-1120. (2016).
Gülcher, A. J. P., Gerya, T. V., Montési, L. G. J., and Munch, J. Corona structures driven by plume–lithosphere interactions and evidence for ongoing plume activity on Venus. Nature Geoscience, 13(8), 547-554. (2020).
Gerya, T. V., Stern, R. J., Baes, M., Sobolev, S. V., and Whattam, S. A. Plate tectonics on the Earth triggered by plume-induced subduction initiation. Nature, 527(7577), 221-225. (2015).
Gilmore, M. S., Collins, G. C., Ivanov, M. A., Marinangeli, L., and Head, J. W. Style and sequence of extensional structures in tessera terrain, Venus. Journal of Geophysical Research-Planets, 103(E7), 16813-16840. (1998).
Herrick, R. R. Resurfacing History of Venus. Geology, 22(8), 703-706. (1994).
Jahn, B. M., Glikson, A. Y., Peucat, J. J., and Hickman, A. H. Ree Geochemistry and Isotopic Data of Archean Silicic Volcanics and Granitoids from the Pilbara Block, Western-Australia - Implications for the Early Crustal Evolution. Geochimica Et Cosmochimica Acta, 45(9), 1633-1652. (1981).
James, P. B., Zuber, M. T., and Phillips, R. J. Crustal thickness and support of topography on Venus. Journal of Geophysical Research-Planets, 118(4), 859-875. (2013).
Johnson, T. E., Brown, M., Gardiner, N. J., Kirkland, C. L., and Smithies, R. H. Earth's first stable continents did not form by subduction. Nature, 543(7644), 239-242. (2017).
Kawamoto, T., and Hirose, K. Au-Pd Sample Containers for Melting Experiments on Iron and Water-Bearing Systems. European Journal of Mineralogy, 6(3), 381-385. (1994).
Kreslavsky, M. A., Ivanov, M. A., and Head, J. W. The resurfacing history of Venus: Constraints from buffered crater densities. Icarus, 250, 438-450. (2015).
Lambert, R. S. J. Archean thermal regimes, crustal and upper mantle temperatures, and a progressive evolutionary model for the Earth. (1976).
Le Feuvre, M., and Wieczorek, M. A. Nonuniform cratering of the Moon and a revised crater chronology of the inner Solar System. Icarus, 214(1), 1-20. (2011).
Martin, H. Adakitic magmas: modern analogues of Archaean granitoids. Lithos, 46(3), 411-429. (1999).
Martin, H., Smithies, R. H., Rapp, R., Moyen, J. F., and Champion, D. An overview of adakite, tonalite-trondhjemite-granodiorite (TTG), and sanukitoid: relationships and some implications for crustal evolution. Lithos, 79(1-2), 1-24. (2005).
McKinnon, W. B., Zahnle, K. J., Ivanov, B. A., and Melosh, H. Cratering on Venus: Models and observations. Venus II: Geology, geophysics, atmosphere, and solar wind environment, 969. (1997).
Morimoto, N. Nomenclature of Pyroxenes. Mineralogy and Petrology, 39(1), 55-76. (1988).
Nimmo, F., and McKenzie, D. Volcanism and tectonics on Venus. Annual Review of Earth and Planetary Sciences, 26, 23-51. (1998).
Pertermann, M., and Hirschmann, M. M. Anhydrous partial melting experiments on MORB-like eclogite: Phase relations, phase compositions and mineral-melt partitioning of major elements at 2-3 GPa. Journal of Petrology, 44(12), 2173-2201. (2003).
Phillips, R. J., Raubertas, R. F., Arvidson, R. E., Sarkar, I. C., Herrick, R. R., Izenberg, N., and Grimm, R. E. Impact Craters and Venus Resurfacing History. Journal of Geophysical Research-Planets, 97(E10), 15923-15948. (1992).
Pollack, H. N. Thermal characteristics of the Archaean. Oxford monographs on geology and geophysics, 35(1), 223-232. (1997).
Richter, F. M. A major change in the thermal state of the Earth at the Archean-Proterozoic boundary: consequences for the nature and preservation of continental lithosphere. Journal of Petrology(1), 39-52. (1988).
Sandwell, D. T., and Schubert, G. Evidence for Retrograde Lithospheric Subduction on Venus. Science, 257(5071), 766-770. (1992).
Schaefer, L., and Fegley, B. Redox States of Initial Atmospheres Outgassed on Rocky Planets and Planetesimals. Astrophysical Journal, 843(2):120. (2017).
Schubert, G., and Sandwell, D. T. A Global Survey of Possible Subduction Sites on Venus. Icarus, 117(1), 173-196. (1995).
Skjerlie, K. P., and Douce, A. E. P. The fluid-absent partial melting of a zoisite-bearing quartz eclogite from 1 center dot 0 to 3 center dot 2 GPa; Implications for melting in thickened continental crust and for subduction-zone processes. Journal of Petrology, 43(2), 291-314. (2002).
Smithies, R. H. The Archaean tonalite-trondhjemite-granodiorite (TTG) series is not an analogue of Cenozoic adakite. Earth and Planetary Science Letters, 182(1), 115-125. (2000).
Smithies, R. H., and Champion, D. C. The Archaean high-Mg diorite suite: Links to tonalite-trondhjemite-granodiorite magmatism and implications for early Archaean crustal growth. Journal of Petrology, 41(12), 1653-1671. (2000).
Smrekar, S. E., Davaille, A., and Sotin, C. Venus Interior Structure and Dynamics. Space Science Reviews, 214(5). (2018).
Solomon, S. C., Smrekar, S. E., Bindschadler, D. L., Grimm, R. E., Kaula, W. M., Mcgill, G. E., . . . Stofan, E. R. Venus Tectonics - an Overview of Magellan Observations. Journal of Geophysical Research-Planets, 97(E8), 13199-13255. (1992).
Steinberger, B., Werner, S. C., and Torsvik, T. H. Deep versus shallow origin of gravity anomalies, topography and volcanism on Earth, Venus and Mars. Icarus, 207(2), 564-577. (2010).
Stern, R. J. The evolution of plate tectonics. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 376(2132), 20170406. (2018).
Streckeisen, A. L. Classification and nomenclature of igneous rockes. Neues Jahrbuch für Mineralogie - Abhandlungen, 107, 144-240. (1967)..
Strom, R. G., Schaber, G. G., and Dawson, D. D. The Global Resurfacing of Venus. Journal of Geophysical Research-Planets, 99(E5), 10899-10926. (1994).
Surkov, Y. A., Barsukov, V. L., Moskalyeva, L. P., Kharyukova, V. P., and Kemurdzhian, A. L. New data on the composition, structure, and properties of Venus rock obtained by Venera 13 and Venera 14. Journal of Geophysical Research: Solid Earth, 89(S02), B393-B402. (1984).
Ueda, K., Gerya, T., and Sobolev, S. V. Subduction initiation by thermal-chemical plumes: Numerical studies. Physics of the Earth and Planetary Interiors, 171(1-4), 296-312. (2008).
Van Kranendonk, M. J., Hugh Smithies, R., Hickman, A. H., and Champion, D. secular tectonic evolution of Archean continental crust: interplay between horizontal and vertical processes in the formation of the Pilbara Craton, Australia. Terra Nova, 19(1), 1-38. (2007).
Yang, H. J., Kinzler, R. J., and Grove, T. L. Experiments and models of anhydrous, basaltic olivine-plagioclase-augite saturated melts from 0.001 to 10 kbar. Contributions to Mineralogy and Petrology, 124(1), 1-18. (1996).