Depression Structures in Unconsolidated Sediments of Great Salt Lake, Utah

Unusual structures, most forming depressions but some domes, occur on the clay flats along the west and northeast shores of Great Salt Lake. They are submerged by the present high water levels (1975) but were exposed at the time of previous studies (1960-1961 and 1971 ). Trenches cutting the structures in cross section and cores taken within and around the structures reveal a variety of forms in layered and contorted clays and unconsolidated silts, sands, oolites, gypsum, and gypsum crystals. Information obtained by Stifel (1964) and by this study is not sufficient or definitive enough to explain the origin of these un usual and puzzling structures. Their origin is open to speculation. Techniques for obtaining peel samples of trench walls are described in detail.