Monday, May 29, 2023

Former Giant Western Red Cedars above Lake Cavanaugh

I have had numerous ventures up the north slope of Frailey Mountain south of Lake Cavanaugh in Skagit County. The slopes are steep and streams on the mountain have had a history of debris flows; hence, I have had numerous ventures assessing the geology risks of the area. 

The forest on the lower sloes is predominantly western hemlock. It is one of the easier forest areas to walk through as there is very little understory brush as the hemlocks shade out just about everything. But amongst the hemlocks are big(!) hints of the past.   

Western red cedar stump amongst the western hemlocks 

Large cedar stump and if you look carefully an even bigger one back in the trees

The western hemlock forest is about 80 years old. The Lake Cavanaugh area was nearly devoid of trees by 1940. There is a small remnant patch of old trees on the steepest upper slopes that were either too hard to log or poor quality timber. 

1941 aerial view of area

The big stumps are a reminder that the forests we see today are not static. Given the age of the forests around Lake Cavanaugh area, there has been significant logging in the area the past few years. As noted in a previous post (HERE), the trees that were left are habitat for marbled murrlets and hence some of the forest is protected. And some of the slopes may be precluded from logging due to potential landslides and debris flow hazards. I say 'may' because that can be a geology judgement call clear cut logging has been permitted on active alluvial fan areas.     

Saturday, May 6, 2023

Colaptes auratus (Northern Flicker) Duel

 I was alerted to the nearby presence of a northern flicker by the drumming on a metal gutter. The bird then swooped past my head and landed on the edge of a plowed area where he confronted another flicker.

The two birds pushed out there chests and faced off for several minutes. Occasionally one would jump upward and the other would respond in kind. 

I do not have a camera that allows for spectacular bird shots, but these were so focused on each other that I was able to witness their activity from about 30 feet and managed a few ok shots while enjoying the drama. What I failed to get was a picture of the nearby female. She was busy poking around for insects behind the dirt clods.  

Thursday, May 4, 2023

Chrysemys picta takes a walk

Approaching a pond in eastern Washington there was a sudden loud splashing. It has been a cold spring, but on this day the sun was warm. The splashing was from turtles jumping into the water upon my approach. 

Turtle heads in the water and one bolder turtle on the shore

While pausing nearby one the the turtles began walking across the grass away from the pond

A bit later I heard rustling and saw the turtle in a patch of bark chips

This turtle kept going across a street and off to parts unknown to me at least

I suspect this turtle is a female and was off to lay eggs some distance from the pond. Painted turtles are common. This particular turtle habitat is clearly not natural with lawn and pavement. But the pond itself is not natural; the pond us part of a broad irrigation system. Prior to the irrigation system there would hev been no turtles within several miles of this location. 


Monday, April 24, 2023

Olympia Nonglacial sediments south of Penn Cove

I had a venture on the east coast of Whidbey Island a bit south of Penn Cove. The geology strata changes rather substantially along the shore. The last time I had been to this shore reach the tide was not favorable but this time I could take in some of the nuances of the bluff geology. 

The carbon-rich layer at the base of the bluff provides an age of about 35,000 years (Polenz, Slaughter and Thorse, 2005). These are non glacial sediments deposited during the period prior to the last incursion of glacial ice out of British Columbia into the Puget lowlands. These non glacial units have been termed Olympia deposits. 

The fine silt/clay layering is horizontal but there is an overprint of oxidized iron staining that confuses the eye as the staining is a bit convoluted. 

It appears that a thin sandy layer had a bit more water flow leaving a darker banding of iron staining. 

I first observed this offset a few years ago and had forgotten about it. I found several other offsets nearby. 

There are a number of fault zones that trend across the Puget lowlands from the southeast to the northwest. These off sets may be associated with those fault zones, but they also could be glaciotectonic. That is the thick glacial ice sliding over the area and loading the land surface with a few thousand feet of ice could be the source of deformation of these pre glacial sediments.
Thick layer of glacial till forming bluff cliffs just to the southeast of the Olympia non glacial sediment exposures and off sets. 


Sunday, April 16, 2023

Observing landscapes I have not been to

I had a long day of travel with a walk to the train station, the long train ride and then the long plane ride. I had a window seat on the flight. I did get a glimpse of northernmost Scotland and the north coast of Iceland. Then flew over landscapes I have never been to and that are not easy to get to.  

Ice cap area of Greenland

Islands and a frozen sound on the west coast of Greenland

Tracks across snow covered ice to and from Uummannaq, Greenland

Large landslide?

I have read tales of arctic ventures across the ice. Good ice on the left and not so good on the right

Glacial striated land with frozen lakes and forest
This time of year might be the best time to travel through this landscape

Gas and oil wells in northern Alberta

Cold Lake Canadian Air Base and the Beaver River

Vegreville, Alberta and snow melt pattern along roads
The Canadian Rockies

Dropping down out of the clouds over Seattle

Monday, February 6, 2023

Asio flammeus on Samish Flats

The Skagit Flats and Samish Flats is birding destination. There are plenty of wintering birds that attract the birders, but the short eared owls are particularly cooperative for observation along Bayview-Edison Road near the mouth of the Samish River into Samish Bay. Besides getting to see them in close flight, the owls have taken to perching on the top of the Fish and Wildlife signs within 60 feet or so from the road regardless of the crowd. On a recent mild sunny day the line of people and cars along the road stretched several hundred meters. The short ear owl is not rare, but their habit of hunting during light allows for much easier viewing than the more nocturnal owls.  

Sunday, January 22, 2023

Winter Field Work

I have developed a preference for geology field work in the winter. Geology field work in western Washington State is generally pretty easy. The hardest challenge in western Washington is the thick vegetation. If you do not like smashing through brush, western Washington off trail field work is not the place for you. In the winter the vegetation is less dense with leaves off of the deciduous trees and bushes. However, Himalayan blackberries with their long canes and thorns still present a problem. On a recent excursion to a slide complex my initial thought was navigating on the slide complex might be limited due to the thick blackberry growth over much of the slide area. However, as I made my way onto the slide I realized the mid December heavy snow followed by freezing rain at the site had flattened down the much of the blackberries making my traverses on the slide complex much easier than initially anticipated. 

I still had to high step a bit to get over the blackberries but it was much easier than if done at another time of year. 

I caught another break with winter weather making my traverse easier after a couple of days steady temperatures well below freezing and before a big snow. I muddy slog with mid shin water and muck. I had been across the same area before. Though the site looked very wet the freeze allowed for easy walking across the frozen mud and frozen ponded water.

The weather does not always work out but, there are the other added benefits: no bugs, easier to see where water has been flowing, and not much worry about dehydration.