Systematic collection and basic discription of the rock samples

抽样组绘制了以下区域的地图，以便在世界各地系统地收集样本。这些造山带分别来自格陵兰岛西南部3.9Ga-3.6Ga的伊苏阿、西澳大利亚的3.5Ga-3.3Ga的皮尔巴拉、2.7Ga-1.9Ga的哈默斯利及邻区、南非的3.5Ga的Barberton地区和2.7Ga的津巴布韦、(3)1.0Ga-0.6Ga的俄罗斯阿拉泰-萨延地区、以及(4)日本犬山的二叠纪-三叠纪硅质岩。这些野外研究旨在破译地球演化的一流地质事件，即(1)Hadean/Archean边界，(2)太古界/元古界，(3)元古代/显生界，(4)二叠纪/三叠纪。对采集的样品进行了岩石学、成岩矿物学和常量元素地球化学的初步描述。以下是研究结果的简要总结。(1)生命起源可追溯至3.9Ga，诞生于大洋中脊热液系统。(2)3.5Ga时，海脊以上水深1600m。XCO2大约是现代大洋中脊的100倍。(3)板块构造可追溯到3.9Ga，当时以刚性板块的存在为标志的现代消费板块边界过程已经开始。(4)潜在地幔温度比现代大洋中脊高150℃。源地幔FeO(10wt%)比现代MORB(8wt%)更丰富。(5)在二叠纪-三叠系界线的大洋岛的深海和近海都发现了超缺氧事件。在广泛汇编全球区域变质带的基础上，提出了元古界-显生宙界线是750 Ma海水回流进入地幔的缘由，并通过新的多砧板实验建立了新的(MORB+水)相图。推测二叠系-三叠系界线的大灭绝是由金伯利岩爆发性岩浆作用和与之相关的光合作用暂时停止所致。这可能与超烟羽活动有关。

The sampling Group has mapped the following areas to collect samples systematically over the world. Those are the orogenic belts from (1) 3.9-3.6Ga Isua, SW Greenland, (2) 3.5-3.3 Ga Pilbara, 2.7-1.9Ga Hamersley and adjacent regions, W. Australia, and 3.5 Ga Barberton region of S. Africa and 2.7 Ga Zimbabwe, (3) 1.0-0.6 Ga Russian Altai-Sayan region, and (4) Permo-Triassic cherts in Inuyama, Japan.These field researches are planned to decode the first-class geologic events of the evolving Earth, namely, at boundaries of (1) Hadean/Archean, (2) Archean/Proterozoic, (3) Proterozoic/Phanerozoic, and (4) Permian/Triassic. All samples collected were preliminary described in terms of petrography, rock-forming mineralogy and major-trace element geochemistry.The followings are the brief summary of our results. (1) Origin of life goes back to 3.9Ga and born at hydrothermal system of mid-oceanic ridge. (2) Depth of seawater was 1600m above ridge crest at 3.5 Ga. XCO2 was ca. 100 times higher than that of modern mid-oceanic ridge. (3) Plate tectonics goes back to 3.9Ga, when modern-stype consuming plate boundary process has already operated by the presence of rigid plate. (4) Potential mantle temperature was 150 C higher than that of modern mid-oceanic ridge. The source mantle was richer in FeO (10wt%) than that of modern MORB (8wt%). (5) Superanoxic event was identified in both deep-sea and off-shore of oceanic islands at Permo-Triassic boundary. Moreover, it was proposed that the Proterozoic-Phanerozoic boundary has been a fate of initiation of return flow of seawater into mantle at 750Ma, based on the extensive compilation of regional metamorphic belts over the world, and a new phase diagram of (MORB+Water) established by new multi-anvil experiments. The mass extinction at Permo-Triassic boundary was speculated to be caused by kimberlitic explosive magmatism and related temporary stop of photo-synthesis. This may be associated with superplume activity.