Dongqiao () is a village in
Amdo County
Amdo County (; ) is a county within Nagqu of the Tibet Autonomous Region of China. The county covers an area of 43,410.85 square kilometres and is dominated by mainly by Tibetan grassland. In 2000 it had a population of 32,843 .
Its capital i ...
of
Nagqu Prefecture
Nagqu (also Naqu, Nakchu, or Nagchu; ; ) is a prefecture-level city in the north of the Chinese autonomous region of Tibet. On May 7, 2018, the former Nagqu Prefecture was officially declared the sixth prefecture-level city in Tibet after Lhasa, ...
,
Tibet Autonomous Region
The Tibet Autonomous Region or Xizang Autonomous Region, often shortened to Tibet or Xizang, is a Provinces of China, province-level Autonomous regions of China, autonomous region of the China, People's Republic of China in Southwest China. I ...
, People's Republic of China. The village of Dongqiao is noted for its hot spring, Jipu. Dongqiao geologically gives its name to the wider Dongqiao-Nagqu Subregion and the Banggong-Dongqiao-Nujiang fault zone.
Geography and geology
Dongqiao is located about west of
Amdo Town
Pana, or Pagnag (), also known as Anduo, or Amdo, is a town and the seat of Amdo County in the Nagqu Prefecture of the Tibet Autonomous Region, in China. It lies 464 kilometres north of Lhasa and 138 km north of Nagqu. As of 2004 its jurisdict ...
.
It is located several kilometres to the south of
Qiangma and
Zigetangcuo Lake
Zigetangcuo Lake ( zh, 兹格塘错) is a crenogenic meromictic lake in the North Tibetan Plateau. It is located in Nagqu Prefecture
Nagqu (also Naqu, Nakchu, or Nagchu; ; ) is a prefecture-level city in the north of the Chinese autonomous regi ...
, to the northeast of
Dongqiacuo lake at an altitude of about .
The
Nu River
, ''Mae Nam Salawin'' (
, name_etymology =
, image = Sweet_View_of_Salween_River_in_Tang_Yan_Township,_Shan_State,_Myanmar.jpg
, image_size =
, image_caption = Salween River in Shan State, Myanmar
, map ...
, also known as the Nujiang River flows nearby forming a valley and the
Nutiang River also flows nearby.
A small valley is located southeast of Dongqiao.
Dongqiao village gives its name to a large region which it is located in which is known geologically for its
ophiolite
An ophiolite is a section of Earth's oceanic crust and the underlying upper mantle that has been uplifted and exposed above sea level and often emplaced onto continental crustal rocks.
The Greek word ὄφις, ''ophis'' (''snake'') is found i ...
, termed the "Dongqiao ophiolite belt", which is dated to the late
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...
to early
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...
age.
The Jurassic age formations form three distinct geological regions to the north of
Lhasa
Lhasa (; Lhasa dialect: ; bo, text=ལྷ་ས, translation=Place of Gods) is the urban center of the prefecture-level city, prefecture-level Lhasa (prefecture-level city), Lhasa City and the administrative capital of Tibet Autonomous Regio ...
, from north to south the
Dongqiao-Nagqu Subregion, the
Doilungdeqen-Lhunzhub Subregion and the
Sangri Subregion.
The northern boundary is known as the Banggong-Dongqiao-Nujiang fault zone or Bangongcuo-Dingqing fault zone, which divides it from the
Qiangtang Terrane to the north beyond this.
Towards the end of the Jurassic period, the ophiolite became covered by
chromitite
Chromitite is an igneous cumulate rock composed mostly of the mineral chromite. It is found in layered intrusions such as the Bushveld Igneous Complex in South Africa, the Stillwater igneous complex in Montana and the Ring of Fire discovery in O ...
.
As
Guangcen Li puts it in a 1990 paper, "the ophiolites appear to be covered in turn by a transgressive marine detrital Upper Jurassic to lower most Cretaceous series."
The
Chinese Academy of Geological Sciences
The Chinese Academy of Geological Sciences (CAGS; ) is an institution that engages in geoscience research in the People's Republic of China. The academy was established in 1956 and reorganized in 1999. Administratively it is under the PRC Ministry ...
has conducted studies in the area, identifying "diamond orebodies of diamondiferous ultrabasic rock type in Dongqiao and Lhobsa of Amdo County, northern Tibet."
The village of Dongqiao is noted for its hot spring, Jipu.
Economy
Due to its geological background, Dongqiao is also a known mining spot, containing the Dongfeng Chrome Mine.
References
{{Nagqu Prefecture
Populated places in Tibet
Amdo County