Webby, 2002:
A series of reef complexes, reefs, and biostromes have been
reported through a carbonate succession 600 m thick at Tiewadian
(Fig. 5) and equivalent sequences of adjoining areas, north of the
Wei River, Shaanxi Province (Ye et al., 1995, Ye et al., 1996). They
occur on topographic highs of the rifted, southwestern margin of
the Ordos Platform (North China Block). At Tiewadian the sequence
includes a composite, 150-m-thick reef complex composed
of superposed biostromes and reef mounds, a 30-m-thick
biostrome, and discrete, large to small, lens-shaped reefs, from 5
to 35 m thick. A wide range of frame-builders and binders are
recorded, though seldom all groups in a single reef or biostrome.
Stromatoporoid Forolinia (probably Labechia), and microbes
Phacelophyton, Renalcis, Epiphyton, Trichophyton, and Girvanella,
are the main contributors. Less important are algae Solenopora,
Vermiporella, and the corals Lichenaria, Cryptolichenaria, Amsassia,
and Eofletcheria. Some larger reefs exhibit a generalized framework
succession: substrate stablization of bioclasts by microbial
(stromatolitic) growth, in places associated with corals or succeeded
by them, and then dominant Forolinia, and/or less common
Phacelophyton, towards the top. Smaller reefs are mainly
stromatolitic. Vermiporella, though recorded by Ye et al. (1996) as
a major reef builder, may have had a more limited role in
sediment production.