Quaternary Geologic Map of the North-Central Part of the Salinas River Valley and Arroyo Seco, Monterey County, California by Emily M. Taylor and Donald S. Sweetkind 2014 U.S. Geological Survey Scientific Investigations Map 3260, 13 p., 2 sheets, scales 1:24,000 and 1:50,000, http://dx.doi.org/10.3133/sim3260 ABSTRACT: Arroyo Seco, a perennial drainage in the central Coast Range of California, records a sequence of strath terraces. These terraces preserve an erosional and depositional history, controlled by both climate change and regional tectonics. These deposits have been mapped and correlated on the basis of field investigations, digital terrain analysis, stream gradient profiles, evaluation of published regional soil maps, and satellite imagery. Seven of the strath terraces and associated alluvial fans have been dated by optically stimulated luminescence (OSL) or infrared stimulated luminescence (IRSL). The OSL and IRSL dates on seven of the strath terraces and associated alluvial fans in Arroyo Seco are approximately >120 ka, >65 ka, 51-46 ka, 36-35 ka, 9 ka, and 2-1 ka. These dates generally fall within the range of ages reported from many well-dated marine terraces on the California coast that are formed during sea-level high stands. Tectonic movements, consistently upward, result in a constantly and slowly emerging coastline, however, the regional effects of climate change and resulting eustatic sea-level rises are interpreted as the driving mechanism for erosion and aggradation in Arroyo Seco. Suggested citation: Taylor, E.M., and Sweetkind, D.S., 2014, Quaternary geologic map of the north-central part of the Salinas River Valley and Arroyo Seco, Monterey County, California: U.S. Geological Survey Scientific Investigations Map 3260, 13 p., 2 sheets, scales 1:24,000 and 1:50,000, http://dx.doi.org/10.3133/sim3260. DISCLAIMERS: This database, identified as SIM 3260, has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty, expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution constitute such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and/or contained herein. Any use of trade, product or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Geological Survey. Although this information product, for the most part, is in the public domain, it also contains copyrighted material as noted in the text. Permission to reproduce copyrighted items for other than personal use must be secured from the copyright owner. DATA FILES: The database can be downloaded via the Web from http://pubs.usgs.gov/sim/3260/. ArcView shapefiles and an ArcGIS geodatabase may be extracted from a zip-compressed file (SIM3260_GIS.zip). In addition, an Adobe Portable Document Format (PDF) file (SIM3260 _sheet1.pdf and SIM3260_sheet2.pdf) can be downloaded, from which paper copies may be printed. The database contact is: Emily M. Taylor 303-236-8253 emtaylor@usgs.gov U.S. Geological Survey Box 25046, Mail Stop 980 Denver, CO 80225 The data were compiled from field mapping and interpretation of DEM data, NAIP imagery, and aerial photographs. Lew Rosenberg and Marith C. Reheis (U.S. Geological Survey) reviewed the geologic map and accompanying text. This geospatial database consists of ArcView shapefiles and ArcGIS geodatabase files contained in a zip archive. See the list below. Please refer to the file SIM3260.met for detailed metadata documentation for this geospatial database. List of files: 00ReadMe.txt SIM3260_pamphlet.pdf SIM3260_sheet01_print.pdf(high-resolution PDF) SIM3260_sheet01_screen.pdf(low-resolution PDF) SIM3260_sheet02_print.pdf (high-resolution PDF) SIM3260_sheet02_screen.pdf (low-resolution PDF) SIM3260.met SIM3260_GISdata.zip: FEATURE CLASSES INCLUDED IN THIS GEOSPATIAL DATABASE: GEOLOGY Feature Dataset: SHAPE FILES in SIM3260_shape folder: ArroyoSeco_flat_locations - flattest location on polygon used for elevation and distance from drainage ArroyoSeco_inset_map_boundary - boundary of inset map ArroyoSeco_label - polygon labels (attributes) ArroyoSeco_line - linear polyline features (contacts, faults) ArroyoSeco_OSLsample - OSL and IRSL sample sites ArroyoSeco_poly - geologic unit polygons LAYER PROPERTIES: Alluvial_Soils.lyr Lines.lyr MapUnitColors.lyr RASTER BASE FILES: ArroyoSeco_hillshd.tif ArroyoSeco_hillshd.tfw ArroyoSeco_topo.tif ArroyoSeco_topo.tfw SIM3260_GIS.gdb directory (contains GIS data as geodatabase feature classes) HOW TO OBTAIN THE DIGITAL FILES: The digital files constituting the geologic map database of this report can be obtained via the Internet from the U.S. Geological Survey publications website. Go to the web page at http://pubs.usgs.gov/sim/3260/ and follow the directions to download the files. The main products are Portable Document Format (.pdf) maps, which require Adobe Acrobat for viewing. Acrobat software runs on a variety of systems, and Acrobat Reader is available for download free of charge from Adobe at http://www.adobe.com.