Sutter's Mill Question… (Topographic Maps)

Sutter's Mill Question… (Topographic Maps)

As given in “Sutter's Mill Question..” at:
http://six.pairlist.net/pipermail/meteorite-list/2012-May/084908.html
Dennis Miller asked:

“For my personal edification, what is the name of
the USGA Quadrangle map you are using. I need
to start another strewn field map, with itty bitty
dots, so far.

1. freewu2000 at yahoo.com replied:

“In Placerville I picked up 15 min topomaps named
Coloma. Also Pilot Hill to the west for where the big
one are speculated to be.”

and 2. Dennis Miller replied:

“Thanks for the map information. I did go to USGS and
ordered Coloma and Pilot Hill topos. The Coloma
(#328961) map is a 2012 aerial map.”

For GIS-minded people, free georeferenced 1:24,000
scale topographic map mosaic for all of El Dorado
County, California can be downloaded from the USDA
Natural Resource Conservation Service Geospatial
Datagateway at http://datagateway.nrcs.usda.gov/ .
For thedownloading the to the “Order by County/Counties” at:
http://datagateway.nrcs.usda.gov/GDGOrder.aspx .

From the above link a person can get free 1. Digital
Raster Graphic Topographic Map County Mosaic by
the NRCS, 2. and 2. high-resolution aerial imagery for
2009 and 2010. Both of these are georeferenced.
Finally, National Elevation Dataset, 3-meter resolution,
is available for download.

Individual georeferenced digital raster topographic
maps are available for free from the Cal-Atlas geospatial
clearinghouse at http://atlas.ca.gov/download.html
and the Cal-Atlas: Imagery Download Tool at
http://atlas.ca.gov/imagerySearch.html . For finding
the topographic maps check /choose the DRG data
layer in the "Download Tool" menu

Coloma 1:24,000 topographic map is “DRG O Series o38120g8.”

Pilot Hill 1:24,000 topographic map is “DRG O Series o38121g1.”

There is a choice of either collared (untrimmed) or
collarless (trimmed) DRGs (Digital Raster Graphics)
for the topographic maps.

I have loaded the individual DRGs for my field areas
into the company Ipad and used available apps to keep
track of my location as a blue dot on the DRG base I
moved around doing fieldwork. The same can be done
with many GPS units or other portable electronics.

Best wishes,

Paul H.

Free Online Topographic Maps of Various Countries

Paul bristolia at yahoo.com
Sat Jun 10 01:44:05 EDT 2006

Scanned images of Russian topographic maps (at scales from 1:10,000 to
1:5,000,000, but mostly 1:100,000 and 1:200,000) of a wide variety of
countries, including Africa, Albania, Liybia, China, Australia, Greece, India,
Indonesia, and so forth are available free of charge at:

http://mapy.mk.cvut.cz/data/

Yours,

Paul