7/5/78 CLARK 15' 7B63 Sec 15. 950 m E & 600 m N of SE cor Sec. 15, T. 56N, R 101W, PARK Co, Wyo. 4 Limestone layers in a med grey SILTSTONE SILTST x LS. CONTAIN MOLLUCKS SILTST is massive & calcareous LACKING any primary sed. STRUCTURES. Limestone layers are rounded Knobby & lenticular in their distribution Believe tht these represent Limesto CALCIUM CARB accumulations in a dry Subsoil SILTST also is a soil w/ calc. carb nodules. Mollucs occur in the SILTST as well as in the LS, Sed content ls nodules -> SILTST not right for small ponds or a floodplain Willwoul Fm. pred oxidizing x soil forming Fm. pred reducing w/ 1° STRS appearng.