SUMMARY
New data on the stratigraphy of Paleozoic sediments in T¶ X×n Thµng and Tµ Ph×nh
(Tña Chïa, Lai Ch©u)
Lª V¨n Vâ, NguyÔn V¨n Nguyªn
Based on recently collected stratigraphic and palaeontological materials, the Paleozoic sediments in T¶ X×n Thµng and Tµ Ph×nh areas (Tña Chïa, Lai Ch©u) can be rearranged as follows:
- Argillaceous shale, silty sandstone, limestone, 250-400 m thick, containing brachiopods, bivalves and corals, assigned to the NËm P×a Formation (D1 np) of Lower Devonian.
- Dark grey limestone, black limestone, 600-700 m thick, containing corals, assigned to the B¶n P¸p Formation (D1-2 bp?) of Lower-Middle Devonian.
- Light grey limestone, 600-700 m thick, containing foraminiferas and corals, assigned to the B¾c S¬n Formation (C-P2 bs), Carboniferous – Middle Permian.