Wachi La Fm
Period:
Devonian, Carboniferous
Age Interval:
latest Devonian-basal Carboniferous
Province:
Bhutan
Lithology and Thickness
Tang Chu Gr are limestones, shales and dolostones. Schematic diagram of Martin (2017) suggests this lower formation is only carbonate facies.
Lithology Pattern:
Dolomitic limestone
Relationships and Distribution
Lower contact
Disconformity onto Pele La Gr (PeleLaQuartzite Fm)
Upper contact
Conformably (?) overlain by Ripakha Fm
Regional extent
GeoJSON
null
Fossils
Age
Martin (2017) displays as coeval to the Tilcho Lake Fm limestone (including underlying hiatus) of latest Devonian to earliest Carboniferous.
Age Span:
Beginning stage:
Famennian
Fraction up in beginning stage:
0.5
Beginning date (Ma):
365.20
Ending stage:
Tournaisian
Fraction up in the ending stage:
0.3
Ending date (Ma):
355.53
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Extract from Legend to "Geologic Map of Bhutan" (Long, S., McQuarrie, N., et al., 2011, Journal of Maps). Age spans estimated from correlation diagrams in Martin, A.J. (2017, "A review of Himalayan stratigraphy, magmatism, and structure", Gondwana Research, 49: 42-80; http://dx.doi.org/10.1016/j.gr.2017.04.031), but these are often controversial.