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Show TERTIARY LACUSTRINE SERIES. 159 the following members of the Bitter Creek, which are much the same in all exposures: SOUTHERN BITTER CREEK. Feet> 1. Upper white limestone and calcareous marl (summit of series) .............. 300 2. Pink calcareous sandstone............................................... 800 3. Pink conglomerate (base of the series)..................................... 550 1,050 In the northern part of the district we have a larger development of the Bitter Creek series, and resting upon it some heavy masses of the Lower Green River shales, and probably a considerable portion of the Upper Green River Group is also represented. There is, however, no exact correspondence in the lithological or stratigraphical succession of the component members of the Bitter Creek when the northern and southern portions of the district are compared A series of sections from the northern part is given in the following chapter. The Pink Cliffs, which form such a striking feature in the scenery of the southern terraces, are exposures of the fine-grained calcareous sandstone, forming the middle member of the Bitter Creek. The same exposures are exhibited in the southern and southwestern flanks of the Marka-gunt around the entire promontory of the Paunsagunt and in the circuit of the Table Cliff. In the Aquarius Plateau the Lower Eocene is found, but in smaller volume than elsewhere, and it is decidedly diminished in mass upon the summit of Thousand Lake Mountain. But it resumes its normal thickness farther north, and then grows more and more massive throughout the extent of the Wasatch Plateau. In their general characteristics these Tertiary strata are similar to the Laramie beds upon which they generally rest, being shaly and marly and sometimes lignitic. It :«s noteworthy, however, that in the southern part of the district of the High Plateaus no lignite or carbonaceous material has yet been discovered in the Tertiary beds. But in the northern part of the district the lignites are found abundantly not only in the Lower Eocene (Bitter Creek), but even in the Lower and Upper Green River (?) beds. In the San Pete Valley coal has been mined for local use for several years, and taken from what appear to be seams of Green River age. A more detailed description of the Northern Tertiaries will be given in the next chapter. |