Whether the Jinzi orogenic movement ever existed is a problem that in-volves the understanding of the structural evolution and mineral explorationin the Lower Yangtze region.At present

the focus of arguments is on the rea-lization of the origin of the carbonate breccia at the base of the Middle and Upper Triassic Huangmaqing Group.Proponents of the basal breccia advo-cate the existence of the movement

while that of the salt-solution brecciaor other secondary origins negate it.In this paper

the authors discuss the primary sedimentary origin of the breccia in terms of its sedimentary features

spatial distribution and occur-rence

and consider it to be a basal breccia.Besides

an analysis of the features of the carbonate breccia exposed at Mr.Yangfang

Chalukou

indicates that this kind of breccia can not beformed by the solution of gypsum and collapse of country rocks.