Tuesday, February 28, 2012

Rail Ballast on the Shoreline

Don't mean to stir the whole coal train pot, but I have been asked a lot about the impacts of heavy trains on slope stability. What I can say is that heavier train loads and traffic does impact rail ballast used to support the rails. This especially true where ballast supports rails across soft saturated sediment as shown below.



It appears the ballast is side dumped off of rail cars and at least some of ballast flowed down the slope into the track side wetland. Some rail replacement work has taken place along this stretch as well as rails on the outside curve were heavily worn. 

Miles of waterfront are owned and managed by the railroads. Not sure if they have a blanket wetland permit.  

Monday, February 27, 2012

Gravel Beach and Wolf Bauer

Shore of the Salish Sea, Port Townsend, Washington
Accreting shoreline with feeder bluff in the distance

Hugh Shipman wrote up a very nice post on Wolf Bauer: http://gravelbeach.blogspot.com/2012/02/wolf-bauer.html. Bauer translated coastal geologic processes in a manner that thousands of Salish Sea dwellers understood and because of him Washington State has shoreline policies that protect not only the public resources of our shoreline but individual property as well.

Hugh himself has done an admirable job carrying on the legacy with the Washington State Department of Ecology. Fellow Bellinghamhamster Jim Johannessen has also been instrumental educational force on shoreline policy as a shoreline consulting geologist.

I do a fair bit of shoreline bluff work in regards to landslide risk. I am frequently impressed with the knowledge of shoreline property owners when it comes to shoreline processes. Frequently they reference the three coastal geologists named above. I had a conversation with a client today who casually mentioned, "the property is located on a feeder bluff" (an eroding bluff that provides sediment to beaches).   

Feeder bluff on the shore of the Salish Sea
  

Saturday, February 25, 2012

Lake Padden Again

Lake Padden watershed and proposed urban growth expansion

I have written about Lake Padden development before: lake-padden-to-urbanize-or-not-urbanize and am not sure I would add much to it other than emphasizing a few procedural/historical points.

The City of Bellingham has designated the Lake Padden area as a future urban area for many years. In 2007 Whatcom County partially pulled the area the city planned to urbanize out of the growth area. A portion was left in that had proposed vested subdivisions and existing urban development. In 2008, the City of Bellingham rejected an annexation petition for that growth area based on the high costs of road, sewer, water, police, fire and stormwater service to the area. Later in 2008 the proposed subdivisions that had been left in the growth area failed to become final due to the inability to obtain water and sewer service. In 2009, Whatcom County again assessed Bellingham's growth plans. The County found that Bellingham's growth area was too large and with a lack of a capital facilities plan for paying for urbanizing the Padden area, the County removed the Lake Padden area from urban growth area status.

The County decision to push back Bellingham's growth plans was challenged to the State's Western Washington Growth Management Hearings Board. However, the Board has never heard the case. Instead the County Council is considering settling the case by simply agreeing to put the area back in the Bellingham growth area. Hence, on Tuesday evening the Council will be voting on putting the area back in the City's growth area despite the fact the there is no capital facilities plan to pay for the infrastructure to serve the area.

Lake Padden is no longer a planning issue. Designating this area as a urban area requires ignoring the huge costs that are documented in the City of Bellingham Annexation Report. The ordinance was written by attorney's representing the real estate developers contrary to planning staff - the planning staff of the county do not support the ordinance. Lake Padden has become a political issue. But then it always has been. The difference is that with the Growth Management Act financing growth plans is much more transparent that it once was.

So while protecting the lake as a water asset is a critical goal, protection of tax payers and utility rate payers should not be forgotten. While development interests in the watershed will claim that stormwater systems can be constructed to protect the lake, policy makers should ask for the detailed plans and costs, including maintenance. Accomplishing that can not be done unless the lake is much better understood.

On a personal note, I am greatly appreciative of the efforts of citizens who recognize how important this issue is and wish them the best. Mike Sato has a nice intro to the water quality issues  http://salishseacommunications.blogspot.com/2012/02/community-led-protection-of-bellinghams.html

And the People For Lake Padden have put together some great information http://www.p4lp.org/

One final note: Reading the Washington Landscape's most read post was a bit on Lake Padden, but it was primarily based on a oblique Google Earth image of an esker on the Waterville Plateau esker-near-lake-padden?

Friday, February 24, 2012

More on Giant Ripples and Big Floods


Two ice-age flood flood bars from the edge of a terrace
Columbia River Valley downstream of Wenatchee, Washington

On a recent trip to Wenatchee, I had a nice view of some giant-ripples associated with one of the Ice Age Floods. These giant ripples are not the only giant ripple sites associated with the huge ice age floods, but they are one of the better sites for actually seeing them for what they are. Other giant ripple sites do not stand out as well.

My project site was on a high terrace on the side of the Columbia River valley near Wenatchee. This is a land of terraces and huge gravel bars deposited during the ice age. It is a very complicated landscape. While I knew the giant ripples were part of the ice age flood story, spending a little time looking at terraces and absolutely huge ancient landslides made me realize that the story of floods and terrace formation along this reach of the Columbia River is complicated.

Richard Waitt provides a good description of the various surficial features in the Columbia River valley near Wenatchee in Tabor and others (1982). Waitt has been one of the modern geology Missoula Flood detectives and has spend considerable time figuring the multiple Missoula floods and the complexities of the Columbia River Valley between Grand Coulee and Wenatchee. More recently  Richard Waitt (2009) provides a summary in a GSA program abstract on his thoughts on large ice age floods in the Columbia at Wenatchee.

After a few days of map reading and connecting terraces and correlating what Waitt wrote in 1982 with his more recent postulations as well as my own observations at the north end of this reach of the Columbia Valley, I made a few self edits to my previous post and was able to do a decent job of assessing the geologic conditions encountered at my project site. If I understand correctly, the giant ripples at West Bar are from a younger flood that the terrace I was working on at East Wenatchee. Waitt postulates that the giant ripples at West Bar (pictured above) may have been either from a late, smallish Missoula Flood that passed down the Columbia after the Okanagan ice lobe had retreated and was no longer blocking the Columbia River upstream, or that the ripples were from some other flood triggered by ice impounded lakes elsewhere. It is pretty easy to imagine surges of water coming down the Columbia Valley in this area from j√∂kulhlaups (surges of sub glacial ice water) from the Okanagan ice lobe or any other ice location.

The Missoula Floods so dominate the landscape of eastern Washington and the Columbia River that it is easy to forget that there were other large floods. For example the Bonneville Flood that surged down the Snake River and down the Columbia was huge, but evidence for that flood is nearly completed obliterated by the Missoula Floods features.    

Thursday, February 23, 2012

Worries About Greece

I found this bit on Greece very interesting both in terms of understanding the challenge in Greece, but also the politics of the situation. Daniel Davies at Crooked Timber introduces an exercise on the Greece debt crisis with an assessment of the current debt plan, "it’s recognizable as a good-faith plan made by conscientious international civil servants working under unimaginably difficult political constraints in an economic context that was irreparably broken before they got there – is, as always, unpopular". Alas, politics is often about fixing irreparably broken schemes - very little attention or credit given for run of the mill success.

crookedtimber.org/2012/02/16/so-what-would-your-plan-for-greece-be

I haven't played out the exercise other than seeing the choices get bad really fast. But it looks like a great time killer.

I do follow economics issues and not just economic geology. I never had any aspirations of owning a company. I studied geology and wanted to do geology work. But working means business and by a few quirks I ended up starting a company in 1997 and have been a business owner ever since and still retain majority ownership of our small company. And after 2008, Greece worries me a bit.

Tuesday, February 21, 2012

Neko Case Sums up Washington: Two Songs for the Season

Neko Case when asked to describe her singing style stated, "Loud", spent part of her formative years in the Washington Landscape. Her song Red Tide ends with a line that sums up how many west  side Washington residence feel towards the end of February and on into March and April and sometimes May and June. And after the last few days for me as well. Update: clear and sunny this morning!


And a listen to Neko should include a song about Washington's second city.

Ice Frosted Birch Trees

Ice flocked birch trees

A little busy still with other work that involves writing as well. Miss the sun and snow and freezing fog in eastern Washington as the wet west side has been days of clouds.

I took the above picture of these birch trees covered by ice from freezing fog during on the inversion days on the east side while heading up above the inversion layer. right near the top of the layer the fog would heavily frost the trees. People pay good money to have Christmas trees flocked. We got the treat for free. 

Saturday, February 18, 2012

Giant Ripples

One of the famous Ice Age Flood sites is the giant ripples southeast of Wenatchee. The ripples are on top of a huge flood worked gravel bar on the west side of the Columbia River across from Crescent Bar. I got a nice enhanced view of the ripples this week as they were partially covered with snow. From a distance they look like sand dunes but in fact are underlain by cobbles and gravel.

Giant ripples near Crescent Bar with Columbia River
Note trees on river bank to get some sense of the scale of the ripples-
the trees are at least a half mile from the ripples

View of two large gravel bars extending downstream.
Crescent Bar is on the left bank

The giant ripples can be seen from Highway 28 between Wenatchee and Quincy.



These ripples were one of the early bits of evidence of giant floods having impacted eastern Washington. The ripples themselves are impressive, but the topography of the valley can also give one a scale of how much water was surging through this area.

Aerial View showing ripples and scour (USGS)

Topographic map of ripples and scour. Click image to get better look.
Note the elevation difference between ripple area and scoured scab land (USGS)

The water surging down the Columbia River valley from at least some of the huge floods was over 500 feet deep! The view point itself would have been under water. Not all of the Missoula Floods flowed through the same route in this area. In the case of ripple area pictured, the flood waters followed a path down the Columbia River. Other flood routes included Moses Coulee a route when the Columbia River river was diverted eastward by the Okanagan ice lobe. At least one and likely several of the Missoula Floods followed this route, but as the ice lobe pushed further south, the Moses Coulee route was blocked as well and the Columbia was pushed into the Grand Coulee where numerous floods surged through and J Harlan Bretz started putting together his story of a catastrophic flood. This particular set of ripples was from one of the later ice age floods associated with the collapse of the ice lobe blocking the Columbia River north of Wenatchee.

Ice lobe extent and Columbia River routes (blue arrows) USGS

A final note - Moses Coulee is named after Chief Moses moses-epic-figure-of-19th-century  as he lived in the Coulee for a fair bit of time and the Coulee was a good trail route up onto or down off of the Waterville Plateau.

Friday, February 17, 2012

Wilkes Provides the Answer to the Wooden Towers at Discovery Bay and Dungeness


View across the entrance of Discovery Bay from the Strait of Juan De Fuca

In 1792, George Vancouver sailed his ship into the Strait of Juan de Fuca, and then into the bay that is now named for his ship, the Discovery. Vancouver observed wooden towers at Discovery Bay and at Dungeness Spit, west of Discovery Bay but he was unable to determine their purpose. Over 50 years later Berthold Seeman (flattery-rocks-berthold-seamann and quotes-from-narrative-of-voyage-of-hms ) sailing on the HMS Herald observed the same towers at Discovery Bay. If there are any remnants of those towers today, I have not observed them, but having done a fair bit of work along the shores of Discovery Bay I was curious about the purpose of these mysterious towers as well.
Charles Wilkes had followed Vancouver's route in 1841, sailing from Hawaii to the Oregon Country. He anchored in Discovery Bay and spent several days exploring. His expedition was charged with gathering information on the Oregon Country. The information was needed by Congress and the President, who were engaged in negotiations with Great Britain as to how the Oregon Country would be divided between the two nations. Wilkes spent a fair bit of time assessing the large bay as a potential port.

His initial reaction was very positive. The bay was large and appeared to be sheltered by Protection Island located at its entrance. The down side was it was deep with abrupt shores, not a very safe setting for sailing ships. Like Seeman, Wilkes described the First Nations people living in Discovery Bay as being in a rather miserable condition.
A land party described travel as nearly impossible, due to the thick vegetation and many downed trees. They observed no wildlife other than birds. I find this description interesting because today the forest around Discovery Bay is reasonably open. It is an area that becomes very dry in the summer, so it is surprising to hear that it was heavily vegetated at that time. This would suggest that when Wilkes was there, burning was not a common practice, or that burning had been discontinued.
But back to the wood towers, which Wilkes observed as well. The local Discovery Bay native people explained that the towers were used to string nets across area where birds would fly. During the night, they would frighten the geese and ducks, flushing the birds from their nocturnal rest. The birds would then fly into the nets where they could be captured quite easily.      
View of Discovery Bay entrance looking to the northwest from above Becket Point

Becket Point with backwater estuary. Perhaps a good place for bird catching net towers.


Thursday, February 16, 2012

My Favorite Day

“What day is it,?" asked Pooh.
"It's today," squeaked Piglet.
"My favorite day," said Pooh.”

At least once per every 5 years I find the urge to read Milne. A great series of books for anyone out and about reading landscapes. Bit busy of late, but today is my favorite day. Saw the above the day after a walk through the woods in the snow. Words to live by.


Tuesday, February 14, 2012

Whatcom County's Leftover Meatloaf

Back in 1994 a few years into the Growth Management Act (GMA) Era in Washington State, the Western Washington Growth Management Hearings Board rendered a decision regarding rural lands in which they used the metaphor "rural lands are the leftover meatloaf in the GMA refrigerator".

As posted previously digesting-lamirds-wonky-long-and-local Whatcom County had a portion of its rural planning leftover meatloaf invalidated by the Western Washington Growth Management Hearings Board. The County Council met in executive session to discuss the matter and accepted all of the ruling except for two areas west and northwest of and adjacent to the City of Bellingham. At this point it is not exactly clear how the County will appeal this ruling. They simply have said they will and that allows them some time to develop and present some kind of argument for the Board's consideration.

The areas in question do present interesting problems. These are not agricultural or forest areas, and, unless you have no faith in implementation of wetland, stormwater and wildlife protection rules, development in this area should not have significant impacts to the environment. However, build out of these areas as proposed by the County Council does pose some problems:

1) Build out of these areas will impact streets and roads and given their location, the travel routes most likely will be onto Bellingham surface streets. One of the reasons Bellingham appealed this scheme. As a simple example that is apparent to Bellingham is Lakeway Drive. If Bellingham has a rush hour back up, Lakeway Drive is it. Bad traffic on Lakeway certainly can be partially attributed to development in the city along side streets off of Lakeway, but a big source of traffic has been the building that has taken place in Sudden Valley outside the city limits in one of those LAMIRDs (limited area of more intense rural development). Costs to improve Lakeway can be derived from development impact fees in the city, but with no impact fees for development outside the city limits, funds for addressing those impacts are not available except from city tax payers. So my local arterial gets plugged with traffic from new homes outside the city and I along with my city neighbors pay for the impacts.

2) Because the two areas are adjacent to Bellingham, allowing these areas to build out at suburban level density with one and two acre lots will very likely preclude these areas becoming more densely developed if the city continues to grow and will force city growth in some other direction. In many regards these areas may make much more sense as future urban areas.

3) Large swaths of land immediately adjacent to the city undermines city planning. The city works to set up development where the community decides is appropriate and that development is undermined by available lots immediately outside the city limits. Given the very large over supply of lots outside the city limits development in the city is slowed counter to the main thrust of GMA.

The type of development scheme being pushed by the County Council in this area has thwarted efficient development at numerous other locations around the state - the doughnut holes of unincorporated areas in the otherwise urbanized areas near Edmonds, Lynnwood and Alderwood are one example. The same type of development pattern to the east of Kennewick has driven Kennewick city limits miles to the west and southwest while the east city limits have changed minimally over a period of 40 years.

Sunday, February 12, 2012

Kennewick's Mountain

My views from above the Columbia Basin inversion posted a couple days ago above-inversion-in-columbia-basin were from Jump-Off-Joe. Many Washington communities have their mountain. For Seattle and Tacoma it is Mount Rainier. For the lower Skagit Valley and western Whatcom County it is Mount Baker. Spokane has Mount Spokane, Yakima has Mount Adams. Kennewick has Jump-Off-Joe. Jump-Off-Joe is the high point on the horizon south of Kennewick. It is high enough that it may be covered with snow when no snow is present in town and its height means it gets a bit more snow and rain than Kennewick. It is Kennewick's mountain, except that it isn't. It is just Jump-Off-Joe without any hill or butte or mountain modifier.

Jump-Off-Joe from base of power line route

At 2,200 feet Jump-Off-Joe is the highest point in 50 miles. Hence, the summit is lined with communication equipment. The summit has line of site views deep into eastern Washington, up the Yakima and Walla Walla River valleys as well as down the Columbia River to the gorge area. The summit is just a bit under 1,900 feet higher than downtown Kennewick. Perhaps nothing to brag about, but I will say this: the last 1,000 feet is very steep. Billy and I headed up there to enjoy the sun above the inversion layer and hiked down the steep face and back up along the power line road. 900 feet of elevation gain in a bit more than a half mile. I remembered why running the entire route to the summit along this road was never done when the steepest section always caused me to walk even when I was in top running condition.

Jump-Off-Joe with its steep northern facing slope is typical of much of the Horse Heaven Hills and the rest of the Yakima Fold Belt with gradual south facing slopes and sharp drops facing the north. Billy and I got to feel that steep slope in our calf muscles and quadriceps. Jump-Off-Joe may not rank the term mountain, but it is Kennewick's Mountain, and walking or trying to run its north face will give one's legs a feeling of having been on a mountain slope regardless of the lack of USGS designation. I will add a fair number of USGS topographic map designated mountains in the area are substantially lower.   

Saturday, February 11, 2012

Jason Overstreet is Outed

Politics does shape our landscapes and how Washington State looks so at times I have and will offer perspectives that may have a leaning. No opinions on this video of Washington State Legislator Jason Overstreet, R-42nd speaking from the house floor via TVW and The Stranger: http://slog.thestranger.com/slog/archives/2012/02/10/what-is-truth-by-republican-representative-jason-overstreet. Click, watch and come to your own conclusions about this Washington State policy leader.

Landslide Screening Tools and Forestry in Washington State

Kara Whittaker contacted me early this Fall to see if I was interested helping on a paper she was working on regarding slope instability screening tools developed by the Washington State Department of Natural Resources. I was honored to help. In the process I learned a lot and found new curiosities that may or may not be pursued.

Whittaker, K. A. and D. McShane. 2012. Comparison of slope instability screening tools following a large storm event and application to forest management and policy. Geomorphology 145–146: 115–122.

http://www.sciencedirect.com/science/article/pii/S0169555X12000141 for abstract

I can share a pdf version for those interested for educational or non-commercial research.

Friday, February 10, 2012

Indian Population, Camas, and Prairie

During Charles Wilkes 1841 travels in what is now western Washington he made numerous observations regarding the Indians of the area. His observations and information related to him provide a key bit of information on how the Indians lived and what their circumstances were at the time of his visit.

He noted that one Indian village on the Chehalis River was being utilized by Nisqually Indians for fishing. He observed rows of eels drying in the sun and baskets of camas. Camas is a root plant that was a fundamental food source. Wilkes noted that the plant was plentiful throughout the southwest Washington prairies. On Wilkes return trip he met Indians who were travelling from Willamette Falls (south of present day Portland) with dried fish in order to trade for camas with Indians in the southwest prairies. This observation is very consistent with observations made by Lewis and Clark forty years earlier. They observed that wide spread trading was taking place between tribes and that camas was readily available.

Wilkes noted the general very low Indian population of the area. The few English, American and French Canadian settlers in the Chehalis area and Cowlitz River area that were familiar with the Indians noted that one nearby tribe had only three female Indians remaining when only 10 years previously there had been 30. At Fort Vancouver, Wilkes met an Indian chief that only 15 years before could summon 300 to 400 warriors. His entire tribe had died from disease. These observations were consistent with those of David Douglas who witnessed what he estimated as 90% mortality of Indians on the lower Columbia River during the winter of 1825.

The mortality that swept though the First Nations peoples of the Pacific Northwest is consistent with observations throughout the Americas regarding huge population declines due to the low resistance to European disease. In many cases the population decline took place even before European contact with tribes took place. Certainly some population decline may have taken place even before any European contact took place in the Pacific Northwest and in many areas of the Northwest and Washington State the first European arrivals came after the population had already declined. However, in the case of the lower Columbia River area and southwest Washington a catastrophic population decline due to disease was observed by members of Hudson Bay Company including David Douglas.

Wilkes seemed to assume that the Indians would completely disappear and accepted this type of population decline as to be expected based on what had been observed in many other American locales. Wilkes also noted an issue regarding Indian health that was of no small consequence. Medicine men often prescribed medicines and activities that furthered the harm to sick Indians. And failed treatments often led to the killing of the medicine man in retribution. The same punishment was brought to bare on Whites that treated Indians. Marcus Whitman and John Black likely were killed for this reason. As such medicine men both White and Indian were hesitant to treat any Indians that became ill with one of the new illnesses.

Wilkes was travelling through a landscape that had previously supported a great many more people. Instead of a few dozen Indians living in the southwest Washington prairies there had been thousands. Not only that, the population had specialized as documented by the trading of camas. The southwest Washington prairies provided a key source of carbohydrates for thousands of local people as well as thousands more via active trading. The prairies Charles Wilkes had traveled through had been depopulated. What he witnessed was more than just a decline in population but also a recently collapsed civilization.

Wednesday, February 8, 2012

Clastic Dikes at Badger Coulee

On the way to BLM land in the Horse Heavan Hills I spotted this road cut through Missoula Flood silts near the west end of Badger Coulee on Webber Canyon Road near Kiona, Washington providing a great exposure of clastic dikes cutting through the various silt units.

Clastic dikes at Webber Canyon Road, Kiona, WA

Close up of clastic dike

Clastic dikes form when sediment deposition compresses older sediments and water is squeezed out of the sediment as the sediment compresses. The water filled with sediment breaks through the overlying sediment and the fracture flow path remains filled with sediment. Clastic dikes are a common feature in the Missoula Floods silt units as well as any location where rapid deposition has taken place.

Although silts are the predominant sediment at this road cut, there are a few cobbles and small boulders embedded within the silts. These silts were deposited in a lake environment as the flood waters backed up at the constriction at Wallula Gap, the narrow Columbia River passage through the Horse Heaven Hills. The lake contained ice bergs from the collapsed glacier dam and an occasional cobble or boulder melted out of the ice would land within the silts.  
Granodiorite cobble within the silts

The clastic dike road cut is located at an interesting area. Prior to the Missoula floods, the Yakima River flowed through Badger Coulee joining the Columbia River a bit downstream of its current confluence. The broad former river valley still remains, but the the west end of the valley was eventually stuffed with enough sediment from the numerous Missoula Floods that the Yakima River found a new route to the north leaving its former valley now Badger Coulee (Bjornstad and Fecht, 2002). A fair bit of this story was figured out within a nearby gravel pit. While the idea of a big ice age flood through eastern Washington put forward by J Harlan Bretz has been accepted, many details of the how the floods have shaped eastern Washington have been worked out since including this old river route.

Location (USGS, 2010)

Former path of Yakima River from Kiona to Kennewick noted with arrows.
Current path of the river is to the north through Horn Rapids then back south

Road cut location on Webber Canyon Road near Kiona
Gravel Pit to the east provides excellent exposures as well but is an active mine

View of Badger Coulee looking east from McBee Road

View of gravel pit that helped unravel the Badger Coulee/Yakima River story.
Goose Hill is rises up behind pit.

Sunday, February 5, 2012

Above the Inversion in the Columbia Basin

I was up on the southern edge of the Columbia Basin looking down on the inversion. Clear nights and  a high pressure ridge over Washington has caused temperatures to drop and cold air to settle into the basin with dense fog forming along the boundary of the cold air below and the warm air above. This is not an uncommon phenomena within the Columbia Basin. I was up on the ridge line of the Horse Heaven Hills at the southern edge of the basin and enjoyed warm sun while looking down on the fog covered basin.

Columbia Basin viewed from Jump-Off-Joe

Summit ridge of Horse Heaven Hills south of Kennewick

View towards Rattlesnake Mountain in distance and Badger Mountain
both rising above fog

There was some breeze over the ridge line and the wind turbines were turning. I heard no noise whatsoever from the wind turbines, but I could hear the train sirens from below the fog located at least 12 miles distant. Simply an anecdotal and striking how noise travels in unexpected ways. 

Double Crested Cormorant in Eastern Washington

Double-crested Cormorant (Phalacrocorax auritus)

I learned a bit about cormorants after spotting the cormorant shown above in an irrigation run off pond in eastern Washington. Cormorants are common site for anyone taking a Washington State Ferry. They often can be seen in the pose of the one pictured above with their wings outspread drying off. I was a bit surprised to see a cormorant in eastern Washington. I thought they were salt water only. But apparently Phalacrocorax auritus can be found in both fresh and salt water and has recently expanded its range up the Columbia River into the Mid Columbia River area.

The two other cormorant species, Brandt's and pelagic, can be seen in the salt water along with the double-crested. I'll have to sharpen my cormorant observation skills to distinguish between these species.

Why the range expansion by Phalacrocorax auritus? I can't answer that, but it is an interesting question. Were the birds in eastern Washington in the past and are just returning to their old range? I can say that habitat areas suitable for the birds has expanded with significantly more wetland areas as a result of irrigation water and water backed up by dams along the rivers. For example, the pond pictured above was scrub steppe land 20 years ago. 

There is also a climate consideration. Even with more habitat can these birds tolerate a periodic extremely cold winter. In this regard, it has been 30 years since the Columbia River last froze over in the Mid Colombia area. How well can Phalacrocorax auritus manage long protracted cold spells with loss of access to food sources? Or will they simply head down river to open water when conditions turn bad? Something to watch for the next time eastern Washington experiences an exceptionally long cold spell. 

Friday, February 3, 2012

Supercontinent Columbia

The farther we go back into earth’s history the fuzzier it gets. Erosion and geomorphic processes erase things. Deposits burry things. Plate tectonics rips chunks of the earth surface apart, moves continents around, slams continents into one another mangling their original appearance, and restuffs ocean floor back into the mantle for recycling. Continental plate movement and cycling of the earth has caused the continents to grow in size as lighter elements have accumulated in the earth’s outer rocks through arc volcanics and scraping of lighter ocean floor sediments onto the margins of the continents. A modern example of that growth can be seen in Washington State with the Cascade volcanoes and ocean floor assemblages such as the young former ocean floor rocks in the Olympics and Willipa Hills of western Washington thrust up onto the leading western edge of North America and thus becoming the new western margin of the North American Continent.

The chunks of continents that drift around get hard to track the further back in time one tries to go. Deep time continental reassembly piecing together the ripped apart ancient continents is a specialty that calls on truly global thinking. Stuff like: part of the east coast of Australia used to be attached to what is now roughly the border of Washington and Idaho and a bit further south was east Antarctica. Or an alternative view that India and northern China were once our neighbors. Hard detective work. Lots of arm waving and really really knowing lots of rock formations from all over the planet and a good grasp of spherical geometry. And this isn’t some old science. Think about it – plate tectonics as a fundamental geologic principle is less than 50 years old. Add to that extracting from rocks and measuring very precisely miniscule amounts of trace elements for age dating and chemical comparison across the globe takes a combination of hard work and very good equipment.

The folks that try to decipher ancient plate tectonics have done an admirable job rolling the clock back by reclosing the Atlantic Ocean 180 million years ago and reversing other plate motions. However, because essentially all ocean floor older than 200 million years has been recycled, going back deeper in time requires different tools than simply running the ocean spreading ridges backwards. Complicated stuff to try to piece together ancient continents. Hurts one’s head reading papers like Counterclockwise exhumation of a hot orogen: The Paleoproterozoic ultrahigh-temperature granulites in the North China Craton (Santosh and others, 2009 in Lithos). Yikes! But fun in a geo global sort of way. Turns out those ultrahigh temperature granulites in North China happen to be similar in age and chemical signature to similar rocks in India and eastern Washington.

Rogers and Santhos (2002) proposed that most of the existing continents came together approximately 1.8 billion years ago. They proposed the name Columbia for this supercontinent as evidence supporting the existence of this supercontinent was significantly derived from rocks in eastern Washington along the east side of the Columbia Basin. We have a supercontinent named after rocks in Washington State! Captain Gray finds the mouth of a big river on a fog free day in the late 1700s and names the river after his boat, Columbia, and now a supercontinent is named Columbia. And this isn’t just any supercontinent; it is the oldest supercontinent that can be reasonably surmized.

Columbia consisted of the ancient continent of Laurentia (the core what later became North America) with West Antarctica, Asia, India and Australia attached to what is now the west side of Laurentia and Europe, Siberia, Greenland and Baltica attached to what is now the north side of Laurentia. The attaching together of continents is a collision process. A modern example is India colliding with Asia creating the Himalaya Mountain belt. The joining of ancient Laurentia with ancient continents on its west side is recorded in highly deformed rocks in Idaho and Montana that were cooked and pressurized 1.6 million years ago.

Columbia existed as a supercontinent for perhaps 200 million years. That is a bit longer than how long the Atlantic Ocean has existed. During this time the supercontinent grew in size as ocean sediments and arc volcanics added to the size of the continent along the edges of the continent.



Columbia - rotated 180 degrees - what is now the west coast was the east coast
Idaho and Australia were neighbors
(Rogers and Santhos, 2003)