Halogenic Formations in the Marginal Zones of Open Continental Seas
Together with formations in which the fades types of modern saline deposition are readily recognizable occur a number of which the depositional environment has no known correlative among modern deposits. They are specific products of past geologic time. For a long time this character was not recognized because of lack of sufficient data. Only now, after extensive borehole information in the U.S.S.R. and the U.S.A. has become available, have the true nature and distinctive character of many marine saline formations become clear. As has been already pointed out, there are two such specific ancient types of saline formations. One accumulated in the marginal zones of open epicontinental seas, the other in huge intracontinental salt-producing seas resting on a complex tectonic structure. Both types will now be described in detail.