More than 20 m thick reef core and 150-200 m wide
Reef builders are massive stromatopores, tabulate corals and cyanophycean algae.
According to ref. 997 overall thickness 182 m.
Boring gastropods.
Marginal reef.

Abstract of ref. 1553:
The present paper describes 10 genera and 18 species of stromatoporoids with such most important forms as Actinostroma clathratum Nicholson; A. cf. crassepilatum Lecompte, Clathrostroma bifarium (Nicholson), Synthetostroma acttnostromoides Lecompte, Stromatopora hupschii Bargatzky, S. cf. cimacensis (Lecompte), S. cf. maillieuxi (Lecompte), Parallelopora ostiolata Bargatzky, P. goldfussii Bargatzky and Stachyodes insignis Yavorsky. These species may be correlated with those of West and South China, and also with those occurring in the equivalent beds of many European countries and Canada, providing evidence for determining the Chitzechiao Formation is late Middle Devonian in age. The Jukoupu reefs occur in the Middle Devonian Chitzechiao Formation, a transition belt with a facies change from open shallow-sea marl to platform shallow-sea carbonate rocks. Based on the difference in sedimentary features, the reefs may be divided into two parts. The reefs in the lower part are clearly stratified and consist of thick-bedded framestones with stromatoporoids and massive corals. The thick-bedded limestones are intercalated with thin-bedded yellow mudstone, marl or mud shale with a thickness of 20-30 cm, indicating short-term and periodic changes in sedimentary environment. The reefs in the upper part are separated from the lower  reefs by a nearly 10 m thick layer of crinoidal limestone. The limestone with a total thickness of 120 m is poorly stratified, containing monotonous fossils mainly with crinoidal stems, dendritic or straticulate stromatoporoids and alveolites. Based on field observation and indoor identification, the Jukoupu reefs may be divided into 8 sedimentary microfacies, namely, micrites with massive stromatoporoids frames; mudstone-shale facies; micrites with massive compound coral frames; sparites with crinoidal fragments; biomicrosparites with biogenic incrustation; biobaffling micrites; oncolite micrites; and bioclastic micrites. The developmental process of the Jukoupu reefs may be as follows: nearshore normal shallow-sea environments.sbd.stromatoporoid reefs developed in the transitional belt.sbd.closed or semiclosed environments of back-reef facies abnormal salinity. The characteristics of the life assemblages and sedimentary facies generally vary with changes in sedimentary environments. Other species discussed are: Actinostroma voivojense, Gerronostroma tenuilaminae, Clathrostroma liujingense, Trupetostroma exquisitum, Stromatopora sinopachytexta, S. liujingensis, Salairella aspersa and Amphipora nonaxis. 