2020-02-07_REVISION - M1977211 (14)

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1100318 R0T0 0811 JRW1 20 (Manitou Formation). As a result of this transgressive sequence, the sediments in the quarry exhibit significant variations in lithology and engineering characteristics with age and depth.49 Within the quarry, brittle deformation features are present in the exposed limestone, sandstone, and granite bedrock, indicating small, unmapped shear zones and faults are present. Secondary, northwest-southeast oriented faults have been mapped as part of this investigation that contributed to forming landslide boundaries. The limestone and sandstone beds within the quarry are also folded to varying degrees. 5.2 Investigation 5.2.1 Geologic Conditions Exponent investigated the geologic conditions at the Pikeview Quarry. This investigation consisted of a review of published geologic maps and prior site-specific geologic reports, review of historical aerial and ground photos, surface mapping of geologic and landslide features, performing a subsurface investigation, and formulating opinions concerning the geologic conditions at the site. 5.2.1.1 Surface Mapping Geologic mapping of the Pikeview Quarry in relation to site topography is presented on the geologic map, and on cross sections A-A' through H-H' (Appendix 39). The following sections discuss the general character and aerial distribution of mapped geologic formations, surficial materials, and bedrock discontinuities. 5.2.1.2 Bedrock and Surficial Materials The bedrock lithologies exposed in the Pikeview Quarry include intrusive igneous rocks of the Pikes Peak Granite, siltstone, sandstone and claystone of the Sawatch Formation, limestone of the Manitou Formation and siltstone of the Pierre Formation. 49 Brainerd, A.E., Baldwin, Jr., H.L., and Keyte, I.A., Pre-Pennsylvanian Stratigraphy of Front Range in Colorado, Bulletin of the American Association of Petroleum Geologists, Vol. 17, No. 4, April 1933, 375-396 (Appendix 38)