The first crater to determine: 64 families-in the pit craters, meteorite-IT information

"Oil in the well, soil can burn. "Gou Zhen Gu long, xiuyan Manchu autonomous county in Liaoning province Su Cun always happen strange things. Villagers here take up water from a well with a layer of oil floating. Also, black earth, dug out to dry, throw into the fire can burn. Since ancient times, gulong village of this phenomenon has always been confusion.

Gulong village landscape is a circular pit, local villagers called "circles". Rolling homes at big pit, pits a rich vegetation, is full of grain and vegetation. Standing on the outside looking down the Ridge, Tai Hang like a sea Bowl. "Movie people" for generations to live here, because traffic inconvenience, villagers depend on silkworm rearing and farming to make a living in the mountains. At present, a total of 64 families, 30 families last name feng. The villagers here seldom get sick, is a famous village life.

▲ On the top of the ring of the crater edge down the sidelines, Bowl-shaped crater landscape spectacular and very powerful form.

However, why these strange phenomena occur in the village?

Institute of geology, Chinese Academy of Sciences Guangzhou he hongping researcher said in an interview with reporters, villagers here life behind, lifestyles are mostly self-sufficient. There is no industry, there is less pollution. In addition, the village is surrounded by mountains, makes it a closed zone, free of outside interference, so these phenomena associated with the pit on the ground.

People's Government of Liaoning xiuyan Suzi town propaganda Committee member Wang Wenpeng told reporters that soil can burn is true, he saw the natives burned black. In fact, this is not a strange thing, experts have given explanations: tens of thousands of years ago, "circle" a large amount of vegetation died and were buried in the ground into carbon, so the soil becomes black "peat". Among them, some soils with high carbon content, which can burn. And because the water cannot flow buried in peat soil, so water naturally bad, there will be oil.

However, Tai Hang and how come? Locals have no way of knowing. To visit the experts do not have a definitive answer. Some people think that this is a crater, others believe that it may be formed by volcanoes or underground nuclear explosions.

In 1982, scientists to "circle" field trip, hope to verify the predictions of the crater is a crater in the village, but ultimately failed.

"In 2000, tangongjiong Professor of the China University of Geosciences with several people came here, was studied for 3 years. At that time, he made the crater is the crater might formed thousands of years ago. Unfortunately, after he was ill, the study also comes to an end. "Wang Wenpeng said that in early 2007, Guangzhou Institute of geochemistry, Chinese Academy of Sciences researcher Dr Chen Ming rate researchers studying in xiuyan, and this unique geographic name" xiuyan pit. " At that time, their surface rocks in the pit area, and did some research.

In March this year, Chen Ming's team once again came here, underground drilling investigations carried out for a period of 5 months in the job. At that time, Wang Wenpeng reception Chen Ming, who, once he went to crater, see drilling depth of more than 300 meters. After the end of the drilling work, Chen Ming won the valuable deep rock samples and the samples were shipped back to Guangzhou in batches for relevant studies.

Wang Wenpeng memories, in fact, in March or April, Chen Ming has confirmed that the crater is the crater, but rigorous, he refused to do interviews with the media. So many people only know there are exploration, but did not know the specific reasons for exploration. Some people even speculated that contain huge mineral resources.

Chen Ming and other researchers through 3 years of hard work, has finally found a meteorite impact lead to deformation in rocks, strongly fractured and partial melting and shock metamorphic rocks and minerals of a range of evidence. On November 30, Chen Ming, who published the results of their research in the scientific bulletin, officially confirmed the Liaoning xiuyan crater is a meteorite impact crater.

▲ Liaoning xiuyan crater panorama

Belongs to a group he hongping with Chen Ming said: "down from the mountain climbing around on the sidelines of the crater, a bowl-shaped morphology as a whole. Crater diameter of 1.8 km, 150 metres deep. Chen Ming by analyzing the pit substance, and identified meteorite impact event occurs in 50,000 years ago. Meanwhile, xiuyan landforms to now make a reasonable guess. Chen Ming thought, meteorite impact crater formed after underground water formed small lakes and lake sediments deposited a few hundred meters thick. About 39,000 years ago, due to lower ' xiuyan ' formed a gap in the East, Lakes disappear, evolved into the Bowl-shaped depression now see. ”

In the international scientific community, meteorite craters judge just by looking at the Earth's surface rocks occur in the ring-like geological structure physical deterioration. In nature, in addition to objects outside the Earth speeding impinging shock wave caused by external, any other natural processes or geological processes were not raised in geological body such minerals physical change. If so, to determine that associated with meteorite impact event.

Fellow of the Chinese Academy of Sciences, Xie Xiande was the study of meteorite impact metamorphism of pioneers in the field, he said to reporters, determine whether the formation of Liaoning xiuyan pit meteorite impact relating to the role, the key is to identify whether the rocks are meteorites strongly impact shock metamorphism associated with. Shock metamorphism is a large meteorite impacting the Earth's surface rocks, metamorphism produced by the shock wave. It can cause deformation and failure of rocks, or partial melting and shock metamorphic minerals occurred.

"From Chen Ming in published papers, you can see that diagnostic index of meteorite craters found in xiuyan. Which fully concluded that xiuyan crater is crater. "Xie Xiande says," meteorite craters (the larger crater, also known as crater) is by the meteorite hit the ground or surface forms the pit or ring structures. On the surface of the Moon, Mars, and mercury and other planets there are many meteorite impact craters. In the early 1960 of the 20th century, the first meteorite impact craters on the surface of the Earth--United States crater-have been confirmed since, so far has found 176 meteorite craters in the world, located in 32 States, ranging from dozens of meters to nearly 300 km in diameter, but this did not appear on the map. ”

"Despite China's Xinjiang, Jilin, Hainan, and other areas have found ' suspected impact crater, but did not find conclusive evidence. "Xie Xiande told reporters that although the first crater to determine, but that does not mean China in the crater area of study just beginning. In fact, exploring the crater started in the 1980 of the 20th century. China craters always goes hand in hand with the international scientific community in the field of research, sometimes even exceeding them. The crater found in xiuyan of Liaoning province to fill the gaps in such unique geological structures on our territory, and also to study the formation and evolution of the Earth, which are of great significance.

"In the future, it can be built as a geological Museum or science base. "He hongping said. Wang Wenpeng told reporters, at present, xiuyan pit has no building is allowed. First, to preserve the scene to facilitate the crater research scientists work; second, it is in order to protect and defend the superior resources of xiuyan Manchu autonomous county.

中国首个陨石坑确定：坑里住有64户人家 - 陨石坑,陨石撞击 - IT资讯

“井里浮油，黑土能烧。”在辽宁省岫岩满族自治县苏子沟镇古龙村总发生这样的怪事。这里的村民从井里取上来的水都浮着一层油。而且，这里的黑土，挖出晒干，扔到火里就能能燃烧。自古以来，古龙村的村民对此现象始终迷惑不已。

古龙村的地貌是一个环形的大坑，当地村民称之为“圈里”。连绵的民宅处于大坑内，坑内草木茂盛，到处是粮田和植被。站在坑外的山脊往下望，大坑好似一只大海碗。“圈里人”祖祖辈辈生活在这里，因为交通不便，村民靠上山养蚕和耕种来维持生活。目前，圈里共有64户人家，有30户姓逢。这里的村民很少得病，是有名的长寿村。

▲登上陨石坑的环状坑缘顶部往下观望，碗状坑景色蔚为壮观，形态极具震撼力。

然而，这个村庄为什么会发生这些怪异的现象？

中国科学院广州地质研究所的何宏平研究员接受记者采访时说，这里的村民生活很落后，生活方式基本都是自给自足。根本没有工业，污染也少。另外，该村被山体包围，使得这里成了一个相对的封闭地带，基本不受外界的干扰，所以，当地的这些现象都与大坑有关。

辽宁岫岩苏子沟镇人民政府的宣传委员王文鹏告诉记者，黑土能烧是真事，他就亲眼见到当地人烧黑土。其实，这并不是什么怪事，专家已经给出了解释：几万年前，“圈里”大量的植被死亡后被埋在地下变成炭，所以，这里的土就变成黑色的“泥炭土”。其中，有些土含炭量高，因而能燃烧。同时又因为埋藏在泥炭土层中的水不能流动，所以水质自然不好，会出现浮油。

然而，大坑又是怎么来的？当地人一直无从知晓。而前来考察的专家也没有一个确定的答案。有人认为这是个陨石坑，有人则认为它可能是火山喷发或者地下核爆炸形成的。

1982年，有科学家到“圈里”实地考察，希望能验证该村的大坑是陨石坑的推测，但最终未果。

“2000年，中国地质大学的覃功炯教授带着几个人来到这里，研究了3年。当时，他提出这个大坑就是陨石坑，可能形成于几千年前。可惜后来他病了，这个研究也就终止了。”王文鹏说，2007年初，中国科学院广州地球化学研究所研究员陈鸣博士率科研人员在岫岩展开研究，并初步将此独特的地理地貌命名为“岫岩坑”。当时，他们在坑区的地表岩石上，进行了一些研究工作。

今年3月，陈鸣的研究团队又一次来到这里，开展了为期5个月的地下钻探勘测作业。当时，王文鹏接待陈鸣等人，有一次他曾前往陨石坑，看到当时钻探深度达300多米。而这个钻探工作结束后，陈鸣获得了珍贵的深层岩石样品，并将样品分批运回了广州进行相关的研究。

王文鹏回忆，其实，今年三四月份，陈鸣已经确认这个大坑就是陨石坑，但为了严谨，他拒绝了媒体的采访。因此当时很多人只知道这里进行了勘探作业，但却不知具体勘探的原因。甚至有些人还猜测，是否这里蕴藏着巨大的矿产资源。

陈鸣等科研人员通过3年的努力，近日终于找到了陨石强烈撞击导致岩石发生变形、碎裂和局部熔融以及岩石和矿物发生冲击变质的一系列证据。11月30日，陈鸣等人将他们的研究成果发表在《科学通报》上，正式证实辽宁岫岩坑就是一个陨石撞击坑。

▲辽宁岫岩陨石坑全貌

与陈鸣同属于一个研究组的何宏平介绍说：“从四周山岭登高向下观望该陨石坑，整个坑形态呈碗状。撞击坑直径1.8公里，坑深150米。陈鸣通过对坑内物质的分析，初步确定陨石撞击事件发生在5万年前。同时，也对现在的岫岩坑地貌作出了合理的推测。陈鸣认为，陨石撞击坑形成后，坑内积水形成了小湖泊并沉积了上百米厚的湖泊沉积物。大约3.9万年前，由于地势较低的‘岫岩坑’东部形成了缺口，湖泊消失，演变为如今所看到的碗形凹地。”

在国际科学界，对陨石撞击坑判别只要看地表环状地质构造中岩石是否发生物理变质。在自然界中，除了地球外的天体超速撞击引起的冲击波作用外，任何其他天然过程或地质作用均不能在地质体中引发这类矿物物理变化。如果有，即可确定与陨石撞击事件有关。

中科院院士谢先德是我国陨石冲击变质研究领域的开拓者，他对记者说，判定辽宁岫岩大坑的形成是否与陨石撞击作用有关，关键是查明该坑岩石是否受到过陨石强烈撞击伴随的冲击变质作用。冲击变质作用是较大的陨石高速碰撞地表岩石时，由冲击波产生的一种变质作用。它可导致岩石发生变形和破裂，或者局部熔融以及矿物发生冲击变质。

“从陈鸣发表的论文中，可以看出陨石撞击坑的诊断性指标在岫岩坑中能找到。这也就充分断定岫岩坑就是陨石坑。”谢先德说，“陨石撞击坑（较大的陨石坑又称环形山）是由陨石体撞击地表或者天体表面所形成的凹坑或环状地质构造。在月球、火星和水星等星球表面存在大量陨石撞击坑。自20世纪60年代初期，地球表面第一个陨石撞击坑——美国巴林杰陨石坑——被证实以来，迄今世界上已经发现176个陨石撞击坑，分布在32个国家，直径由数十米到近300公里不等，但此前没有一个出现在中国版图上。”

“尽管在我国的新疆、吉林、海南等地区发现过‘疑似陨石坑’，但都没有找到确切的证据。”谢先德对记者说，虽然我国的首个陨石坑才确定，但这并不代表中国在陨石坑的研究领域刚起步。事实上，我国探索陨石坑于20世纪80年代就开始了。中国在陨石坑的研究领域一直与国际科学界齐头并进，有时甚至还超过他们。此次在辽宁岫岩发现的陨石坑填补了我国领土上此类独特地质构造的空白，也对研究地球的形成和演化等有重要意义。

“以后，这里可以建成一个科普基地或者地质博物馆。”何宏平说。王文鹏则向记者透露，目前，岫岩坑已经不允许进行建筑。其一，是为了保留现场，以方便科学家进行陨石坑的研究工作；其二，则是为了保护和维护岫岩满族自治县的这一优势资源。