Oudomxay Province, Laosi

Regional Level Types
Oudomxay Province	Province
Laos	Country

Oudomxay Province (also spelled Oudomxai or Udomxai) is a mountainous province in northern Laos, covering approximately 15,370 km². It borders Phongsaly Province to the north-east, Luang Prabang Province to the east and south-east, Bokeo Province to the west, and China (Yunnan Province) to the north-west. The provincial capital is Muang Xay (Oudomxay). The province occupies a strategically important position between Laos and southern China.

Geographically, Oudomxay is dominated by rugged mountainous terrain, with steep slopes, narrow valleys, and extensive forest cover. Elevations commonly range between 300 and 1,800 m, with higher ridges locally exceeding this. The province lies within the upper catchments of several river systems, including tributaries of the Mekong River, such as the Nam Ou and Nam Beng. The climate is tropical monsoonal, with a distinct wet season and significant rainfall, contributing to dense vegetation and frequent slope instability.

Geologically, Oudomxay Province lies within the Indochina Block, a major tectonic terrane of Southeast Asia. The region is underlain by a complex assemblage of Palaeozoic and Mesozoic sedimentary, volcanic, and metamorphic rocks, strongly deformed by multiple phases of orogeny. Folded and faulted sandstones, shales, limestones, and volcanic rocks are common, with intrusive bodies occurring locally. Karst landscapes are developed where carbonate rocks are exposed. Active faulting related to regional tectonics continues to influence geomorphology.

Oudomxay Province has a modest but locally significant mineral and extractive heritage. Small-scale mining and quarrying have targeted gold, copper, and base-metal occurrences, often in structurally controlled veins and altered zones. Industrial minerals, including limestone, clay, and construction stone, are more widely exploited for local use. Alluvial sediments in river valleys may contain placer minerals, though systematic large-scale mining is limited. Mineral collecting and extraction are generally regulated by national legislation.

Historically, Oudomxay has been a remote frontier region, inhabited by diverse ethnic groups and linked to trade routes between Laos and southern China. During the colonial period it lay within French Indochina, and since 1975 it has been part of the Lao People’s Democratic Republic. The province’s rugged terrain and limited infrastructure have shaped settlement patterns and economic development.

Administratively, Oudomxay Province is subdivided into districts (muang). Its mountainous geography, complex geology, and position along regional tectonic belts make it a region of interest for understanding Indochinese orogenic evolution and small-scale mineralisation in northern Laos, even though large industrial mining remains limited.

Fossils

There are 2 fossil localities from the PaleoBioDB database within this region.

These data are provided on an experimental basis and are taken from external databases. Mindat.org has no control currently over the accuracy of these data.

Occurrences	2
Youngest Fossil Listed	191 Ma (Early Jurassic)
Oldest Fossil Listed	272 Ma (Permian)
Stratigraphic Units	Unit No. Occurrences Age Lufeng - Zhangjiawa 1 199.3 - 190.8 Ma (Early Jurassic)
Fossils from Region	Click here to show the list.
Accepted Name Hierarchy Age Lufengosaurus huenei species Animalia : Chordata : Reptilia : Dinosauria : Massospondylidae : Lufengosaurus : Lufengosaurus huenei 199.3 - 190.8 Ma Early Jurassic Waagenophyllum (Waagenophyllum) indicum species Animalia : Cnidaria : Anthozoa : Stauriida : Waagenophyllidae : Waagenophyllum : Waagenophyllum (Waagenophyllum) indicum 272.3 - 252.17 Ma Permian
Fossil Localities	Click to show 2 fossil localities

Other Databases

Wikipedia:	https://en.wikipedia.org/wiki/Oudomxay_Province
Wikidata ID:	Q465961
GeoNames ID:	1654491

Localities in this Region

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