Colorado Scientific Society Field Trips, 2020 plus

The Colorado Scientific Society usually has a Spring and a Fall field trip, with field trip guides, maps and other illustrations, and pictures of people learning and enjoying themselves. The most recent field trips are listed first.

The field trip guides for some field trip’s can be downloaded, usually as PDFs. The size of files larger than 3 MB is called out in the link, e.g. “Quaternary San Luis Basin, Ancient Lake Alamosa, 2007 (PDF 4.6 MB)”.

Field trips are presented with the most recent first. Some field trips with many pictures and maps have their own pages.

2020

Corral Bluffs, the Rise of Mammals and the Recovery from the K/Pg Mass Extinction, September and October 2020

CSS 2020 Fall Field Trip, September 20 and October 4, 2020
Leader: Sharon Milito

These were two one-day field trips to Corral Bluffs, east of Colorado Springs, with its record of the recovery of ecosystems in the first million years after the K/Pg extinction and the rise of the mammals.

This field trip has its own page: Corral Bluffs and the Rise of the Mammals, Sept/Oct 2020

2021

Toe Thrusts and Turtle Toes –
Trackways and Tectonics of the Boulder-Weld Allochthon, September and October 2021

CSS 2021 Fall Field Trip, September 25 and October 2, 2021

Leaders: Sue Hirschfeld, Beth Simmons, Bruce Trudgill, Bob Raynolds and Ned Sterne

These were two one-day field trips to the Boulder, CO area to examine:

The recent discovery at Cherryvale of dinosaur and non-dinosaur fossil tracks in floodplain deposits of the Laramie Formation, as laid down along the shoreline of the retreating Western Interior Seaway at 68-69 Ma. The trackways occur among the historical workings of the Boulder-Weld coal field, which date as far back as 1859.
New structural interpretations of the Boulder-Weld Allochthon, the 216 mi² remnant of a once larger feature, that moved east up to two miles from the flank of the Front Range into the western part of the Denver Basin. Excellent outcrop exposures and subsurface well control in the Cherryvale and White Rocks areas reveal thrust and normal faults developed above the basal decollement of the allochthon as it ramped 900 feet up-section between bedding-parallel detachments in the Upper Transition Member of the Pierre Shale.

This field trip has its own page: Toe Thrusts and Turtle Toes – Trackways and Tectonics of the Boulder-Weld Allochthon, Sept/Oct 2021

2022

PreCambrian Colorado (PC²) Field Trips

PC² = PreCambrian Colorado

Mission: Contribute to the geologic and economic geologic knowledge bases of the Precambrian rocks of Colorado (and to their relationship to the correlative units outboard of Colorado

The initiative is designed to add value to efforts of frontline researchers and to spearhead, encourage, and support current and future research into the Colorado Precambrian through multiple media of field trips, symposia, topical sessions, workshops, short courses, grants, etc. The effort is intended to span the next two years and beyond, working through organizations such as GSA, CSS, DREGS, Universities, etc.

Local Pre-Trip Run for GSA Trip #403: August 20 & 21, 2022

Central Colorado Front Range

Lew Kleinhans, lewis.oysterclub@gmail.com
Lisa Fisher, lisa.fisher@escalantemines.com
Thom Fisher, thom.fisher@escalantemines.com

This is an excellent opportunity for Professors, Students, Researchers, Staff, and Local Geologists to examine part of the Precambrian Geology of the Central Front Range. Whether you are new to the area, new to the Precambrian, or seasoned and informed regarding this area and topic, please join us. Of course you will also be welcome to register for the GSA trip, where additional attendees may bring more ideas to the group.

We will examine and discuss what we know about the Colorado Accretionary Complex here in the Central Front Range. Attention is given to the Petrology, Protolith, Metamorphic Grades and Reactions, Stratigraphy, and Economic Geology/Metallogeny, and how this information brings together the Tectonic Interpretation. Yet several puzzles, inconsistencies, and some arguments remain to be solved here, and this should produce some very interesting discussion on the outcrop.

The study of these ancient complexes brings together several specialties in geology.
Not a metamorphic geologist? Meta-sediments still need to be understood in terms of their original sedimentology (both clastic and carbonate) and stratigraphy; sequence stratigraphy is still obvious to some degree in areas, and basin evolution and interpretation still must be done. Volcanology of the meta-volcanics is critical. Additional geochronology is always needed. Much of our interpretation depends on geochemistry. Structure is complex, with much more remaining research needed. Mineral and metal occurrences, whether economic or sub-economic play an important role in our understanding of the complex.

Itinerary

Saturday, August 20:

Focus: Examination of the Units of the Accretionary Complex of the Central Colorado Front Range (CCFR)
Meeting Time: 7:30 am
Meeting Location: West (uphill) end of Wooly Mammoth Park & Ride @ US-40 and I-70
Tentative Itinerary:: Volcanic Arc, Back Arc, and Basin Metasediments at Various Metamorphic Grades including Anatexis

Sunday, August 21:

Focus: Some Evidence (or Not) of Precambrian Age CCFR Base Metal Mineralization
Meeting Time: 7:30 am
Meeting Location: West (uphill) end of Wooly Mammoth Park & Ride @ US-40 and I-70
Tentative Itinerary:: FMD Mine, Malachite Mine, Creswell Mine roadcut(?), Rutile- and Topaz-Bearing Gneiss

Lew Kleinhans, lewis.oysterclub@gmail.com
Lisa Fisher, lisa.fisher@escalantemines.com
Thom Fisher, thom.fisher@escalantemines.com

Flyer with details about PreCambrian Colorado Local Pretrip on Aug 20-21.

2022 Colorado Scientific Society Fall Field Trips

No Moss Gatherings

As in “a rolling stone gathers no moss“.
These are usually half day trips close to the Denver area.
Pete Modreski started these in the Spring of 2022, to encourage CSS members to get out after the Covid-19 shutdown.

CSS “No Moss Gathering”
Central City Gravel: A Pleistocene Till with Profound Geomorphic Relationships

Saturday, October 8, 2022 at 7:30 am – 12:00 pm

Trip Leader: Cal Ruleman, cruleman@usgs.gov

Join us Saturday, Oct. 8, to visit the Central City Gravel, a Pleistocene till, with geomorphic relationships related to the glaciofluvial erosion of the Front Range and Denver Basin and alluding to Neogene tectonics.

Please plan to carpool from the Wooley Mammoth parking lot off I70. We should return by 12 pm.
Please email Cal Ruleman at cruleman@usgs.gov if attending, and if you can carry people in your vehicle tell him how many you can take.

CSS “No Moss” Hike
Huntsman Gulch

Sunday, November 6, 2022 at 8 am

Trip Leader: Lew Kleinhans

Huntsman Gulch is on the north side of US 6 in Clear Creek Canyon, about 3.9 miles west of the intersection of US 6 with CO 93 and CO 58 west of Golden.

Location of Huntsman Gulch on Google Maps. The map will be centered on the parking for Huntsman Gulch. (Huntsman Gulch is not labeled on Google Maps.)

Time: Meet at 8 am in Huntsman Gulch parking area, in front of rock barricade on north side of US 6 in Clear Creek Canyon.

Plan: This hike will about a three-hour loop hike up the Huntsman Gulch trail to the saddle overlooking Guy Gulch; and then back along the ridge above Clear Creek. Foci will include the fault splay off the Junction Ranch fault, including large boulders in the parking lot, old quarry exposure, and location of Crystal Cave; “recent” sediments below Huntsman Gulch fork above quarry; cross-cutting pegmatite; unconsolidated gravels on slopes / ridge to the north (we won’t hike here); view from saddle overlooking Guy Gulch; ridge-top hike back to barite-base-metal prospect above quarry; and back down to trail.

Note: Hike involves about 700 feet of elevation gain on the partly steep trail with some loose gravel; and finally, an about 400-foot drop back to the trail on a steep, largely trail-free, vegetated slope.

CSS No Moss trip Nov 6, 2022 to Huntsman Gulch flyer and description

Get Huntsman Gulch Suppliment.pdf (on dropbox.com) for a 19.4 MB illustrated field trip guide.

Huntsman Gulch Trail description on alltrails.com

2023

Touring Pikes Dome
Deformation of the Rocky Mountain Erosion Surface and Its Effects on Landscape Evolution and Drainage Reorganization across the Colorado Piedmont and Front Range

September 9-10, 2023

Ned Sterne*, Cal Ruleman**, Bob Raynolds***, and Steve Keller****
*Independent Geologist, ** United States Geological Survey, ***Denver Museum of Nature and Science, ****Colorado Geological Survey

This field trip has its own page: Touring Pikes Dome; Deformation of the Rocky Mountain Erosion Surface and Its Effects on Landscape Evolution and Drainage Reorganization across the Colorado Piedmont and Front Range, Sept 2023