Laserfiche WebLink
SUMMIT ENGINEERING C 0 1 ENGINEERS & LAND SURVEYORS <br /> Mail: P.O. Box 1897 Alamosa, CO 81101 P: 719-589-6147 E: summitengco@gmail.com <br /> /yJ <br /> Al <br /> T`. P <br /> T i Oo� <br /> 1 <br /> €J I �cx • F� � •�� f i vy� ', <br /> • j •,,-' .iir err" t•, <br /> Rock Pit <br /> 4 <br /> All,8� <br /> - .••.�Fe to ..(� ♦ :y �'� ; � > <br /> • 1. �••i� �' ��•I•.. • ��` �. <br /> Antonito a <br /> °� �� .s �. .s � •s <br /> Geologic Map of the lower Conejos River Canyon Area, Lipman 1975 <br /> HINSDALE.FORMATION(PLIOCENE AND MIOCENE)! <br /> nasallic Issas-- Fine-grained stlictc alkati•ollvine basalt and hassitle m,m <br /> Sparse small olivine phenocrysts,partly altered to"iddingsite."are typical. MOM.: <br /> and aenocryvil of quartz and feldspar are locally abundant Groundmaw <br /> is largely andesine,sugite•and olivine. K-Ar ages of(tows ranee from 4A <br /> to_ <br /> 6.A m.y. Older now.form scattered mesatappingomcional remnann. <br /> but little-eroded younger flows in eastern part of mapped airs define a <br /> large eastward-tilted shield volcano.with the major vent area centered at <br /> Liss Mogotes. Local contacts drawn within unit indicate boundaries be- <br /> tween prominent now% Thickness 0-300 m <br /> TIP LOS PINOS FORMATION(PLIOCENE TO OLIGOCENE) Mostly bedded <br /> - - wnelon eralm sandstones,and mud-flow brecciss containing rhyodacite <br /> and quartz latite clats dedvsd from stnfuvolcanoes on the nanks of the <br /> Platmo alders to the northwest and smaller volcanic centers to the soul <br /> Locally includes thin Ws of ash-fall and nonwelded ash-flow ruff. Ac- <br /> cumulsted as crnitsscing alturial-fan deposits on west side of the subsiding <br /> San Luis Ya11ey Internngers with basalt flows of Hinsdale Fomrsfhm <br /> varysnp in sae from about I to 74 m y thicir"o-O-N)n m <br /> Job # 1200710MP - C Page 16of79 <br />