Star dune: Scientists solve mystery behind Earth's largest desert sands
科学家揭晓全球最大沙丘之谜,已有万年历史
The age of one of Earth's largest and most complex types of sand dune has been calculated for the first time. Star dunes - or pyramid dunes - are named after their distinctive shapes and reach hundreds of metres in height. They are found in Africa, Asia and North America, as well as on Mars - but experts had never before been able to put a date on when they were formed. Now scientists have discovered that a dune called Lala Lallia in Morocco formed 13,000 years ago.
地球上最大、最复杂的沙丘类型之一的年龄首次被计算出来。
星形沙丘(或称金字塔沙丘)因其独特的形状而得名,高度可达数百米。
它们分布在非洲、亚洲和北美洲,以及火星上,但专家们以前从未能确定它们形成的时间。
现在。科学家们发现,摩洛哥一个名为“拉拉拉利亚”的沙丘形成于1.3万年前。
科学家揭晓全球最大沙丘之谜,已有万年历史
The age of one of Earth's largest and most complex types of sand dune has been calculated for the first time. Star dunes - or pyramid dunes - are named after their distinctive shapes and reach hundreds of metres in height. They are found in Africa, Asia and North America, as well as on Mars - but experts had never before been able to put a date on when they were formed. Now scientists have discovered that a dune called Lala Lallia in Morocco formed 13,000 years ago.
地球上最大、最复杂的沙丘类型之一的年龄首次被计算出来。
星形沙丘(或称金字塔沙丘)因其独特的形状而得名,高度可达数百米。
它们分布在非洲、亚洲和北美洲,以及火星上,但专家们以前从未能确定它们形成的时间。
现在。科学家们发现,摩洛哥一个名为“拉拉拉利亚”的沙丘形成于1.3万年前。
瑞士发现了7000年前的犁地痕迹 (plough marks), 在Anciens Arsenaux site in Sion, Valais, 年代测定为5100–4700 BC, 是欧洲最早的。
新石器时代农业革命,人们开始种庄稼养牲畜之后,就开始开发其它动物资源,比如挤奶、剪羊毛、让动物干活之类的。
犁地痕迹还是挺明显的。"They consist of linear depressions filled with sediment of a different texture and colour than that of the surrounding deposits. Such marks can be followed over dozens of meters to form parallel or criss-crossing networks. They imply the use of a specific tool, the ard and its traction by a powerful animal such as an ox."
这个Anciens Arsenaux site最早有人定居是新石器时代早期,5244–4914 cal BC, 有post-holes, hearths, 陶器、弯月型的刀、millstones, 大麦与小麦种子等的遗存,是个成熟的新石器文化。这个时期的土层被命名为 "N1".
发现plough marks的土层是 "AG1".
各土层年代见图2。
图3是现场的AG1 plough marks. 土里各种样品都做了micromorphological analysis之类的。
"This approach makes it possible to identify disturbances in the soil horizons caused by tillage."
"The technique involves examining sediments hardened with synthetic resin under a microscope. It has been successfully applied to archaeological sites for several decades."
doi.org/10.1057/s41599-024-02837-5
#StoneAgeEurasia#
[微风][微风][微风]
新石器时代农业革命,人们开始种庄稼养牲畜之后,就开始开发其它动物资源,比如挤奶、剪羊毛、让动物干活之类的。
犁地痕迹还是挺明显的。"They consist of linear depressions filled with sediment of a different texture and colour than that of the surrounding deposits. Such marks can be followed over dozens of meters to form parallel or criss-crossing networks. They imply the use of a specific tool, the ard and its traction by a powerful animal such as an ox."
这个Anciens Arsenaux site最早有人定居是新石器时代早期,5244–4914 cal BC, 有post-holes, hearths, 陶器、弯月型的刀、millstones, 大麦与小麦种子等的遗存,是个成熟的新石器文化。这个时期的土层被命名为 "N1".
发现plough marks的土层是 "AG1".
各土层年代见图2。
图3是现场的AG1 plough marks. 土里各种样品都做了micromorphological analysis之类的。
"This approach makes it possible to identify disturbances in the soil horizons caused by tillage."
"The technique involves examining sediments hardened with synthetic resin under a microscope. It has been successfully applied to archaeological sites for several decades."
doi.org/10.1057/s41599-024-02837-5
#StoneAgeEurasia#
[微风][微风][微风]
VVD
Like I've said many times in recent weeks, we have to just enjoy the ride.
I said it to the boys, if you think back 12 months where we were and the struggles we had, ups and downs, the consistency that was missing, and look where we are right now. It's something we don't take for granted because sometimes in life, in football these things happen and I want to make sure we enjoy this as well, and I think [in the] second half we certainly did.
Like I've said many times in recent weeks, we have to just enjoy the ride.
I said it to the boys, if you think back 12 months where we were and the struggles we had, ups and downs, the consistency that was missing, and look where we are right now. It's something we don't take for granted because sometimes in life, in football these things happen and I want to make sure we enjoy this as well, and I think [in the] second half we certainly did.
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