Geological Outings Around the Bay: The Cordelia and Green Valley Faults

The San Andreas fault is called the boundary between the North American and Pacific plates. It gets a lot of attention, but the plate-tectonic action actually is spread over a wide band of active faults on both sides, west and east, of the San Andreas proper. The easternmost strand of the San Andreas fault zone lies in Napa and Solano counties. This simple road trip will get you acquainted with it.

The textbooks say that the thin bright line of the San Andreas fault is the plate boundary, but in real life the North American plate is deeply splintered halfway to the Rockies. North America and the Pacific have about 2 inches a year of motion between them. The San Andreas proper accounts for the majority of that, but lesser faults in the Coast Range like the Hayward, Calaveras, Rodgers Creek and Maacama take up a large share too. Even the crustal cracks east of the Sierra Nevada move a few millimeters a year. Basically, the whole Bay Area sits within the plate boundary.

Around here, the easternmost part of that boundary consists of the Greenville/Concord fault in the East Bay and the Green Valley fault in the North Bay. The two faults are considered to be connected, although they are offset a few kilometers from each other beneath Suisun Bay. Both are worth a day trip, but let's go north this time. Here's a look at the geology of the area between Fairfield and Napa.

The purple area is young lavas and related rocks of the Sonoma Volcanics. The green area is much older sedimentary rocks of the Great Valley Sequence; we won't see those. The gold in between is widespread landslide deposits .

We'll start west of Fairfield at the Green Valley Road exit from I-80 eastbound, which is just before the intersection with I-680. From 680 take exit 70 and take three right turns to reach Lopes Road, which becomes Green Valley Road. Now the fun part begins as you make your leisurely way into Green Valley. The valley is bounded along its west side by the Green Valley fault, which runs north into private land in the rugged hills. The Green Valley fault seems to rupture every thousand years or so (and last ruptured between 1600 and 1800), but there isn't much data. There is some creep motion measured on it.

The Green Valley fault is not easily visited, but its smaller sibling is—the Cordelia fault. It runs through the lava hills on the east side of Green Valley. About 3.5 miles up Green Valley Road, Rockville Road exits to the right. Take it over the hills for about a mile and a half until you reach a dramatic roadcut. This is it looking west from the far side. On the geologic map above, it's at the north end of the Cordelia fault.

North American Time Zone Map - News


Geological Outings Around the Bay: The Cordelia and Green Valley Faults
Geological Outings Around the Bay: The Cordelia and Green Valley Faults

On the geologic map above, it's at the north end of the Cordelia fault. Pull over and find the distinct trace of the fault, made obvious where the finely ground rock, or gouge, in the fault zone has crumbled out. The west side of the Cordelia fault is



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Frankly Apple should just commit to Thunderbolt and put those ports right on there. There is really no need for any other port.The main reason Apple sticks with the 30pin Dock Connector is size. Thin wise. Displayport is much too thick. One of the reasons they bailed on firewire on the First Gen iPod was the size. Micro USB is probably the thinnest connector out there I would imagine, but does that allow data syncing and at speeds faster than USB 2.0 ??? I don't know. The dock connector must allow for more flexibility on Apple's part I would imagine. Having two different colors means nothing, but now you're dealing with two different thicknesses, plus two different button layouts, meaning a total of 4 DIFFERENT versions of supposedly the same phone, all requiring their own slightly varied case (seeing how a lot of cases designed for the black iPhone 4 will not fit the thicker white models - and how some need to be changed for CDMA and GSM versions). The guys are great in adding some extra info i requested. Small bummer: the current version of the widget doesn't work anymore (it has no idea the xml file changed - no AI yet, sry). I'll try to do a quick fix by the end of the week (should be faster, just not in the mood right now :cool: ). 1.0 should be out before the end of the month (september that is ;)). One thing that is important to investors is the ranking of units shipped (in comparison to other companies.) Apple is currently 4th behind Gateway -- but VERY close!! Q4 2006 should bring Apple to the 3rd place for US shipments in America, behind Dell and HP. That will turn a lot of heads. Q3 Shipments (http://www.macdailynews.com/index.php/weblog/comments/gartner_apple_mac_grabbed_61_of_us_market_share_in_q3_06/) This week XtremeMac posted their iPod Touch 4G online. I was ready to pull out my credit card and make a purchase but I decided to swing by Staples one more time to see if they were in stock. The previous weeks Staples had marked down all their 2G XtremeMac cases. So I was hoping it would be in stock. Well I picked one up tonight and was extremely excited to see that the case feels just as good as the previous line.


North American Time Zone Map - Bookshelf

United States Map Skills (ENHANCED eBook)

United States Map Skills (ENHANCED eBook)

North American nations not shown on the map are Antigua and Barbuda, Bahamas, Barbados, ... TIME ZONES OF NORTH AMERICA Student Activity Objectives: 1 . ...

The American nation, beginnings to 1877

The American nation, beginnings to 1877

Why did people set up a system of standard time zones? 7. ... The American Land FIND OUT ■ What landforms are found in North America and South America? ...

National Geographic concise atlas of the world

National Geographic concise atlas of the world

... Table of Contents 48 NORTH AMERICA 4 INTRODUCTION 8 USING THIS ATLAS 10 ... 46 World Time Zones Time Zones • International Date Line 50 Political Map 52 ...

Frommer's South America

Frommer's South America

The third time zone includes the state of Acre and the western part of the ... The time difference between cities in Brazil and North America varies by up ...

Reference books for young readers, authoritative evaluations of encyclopedias, atlases, and dictionaries

Reference books for young readers, authoritative evaluations of encyclopedias, atlases, and dictionaries

Thus, for example, a user looking at the map of North America can see at a glance that ... Inside the back cover is another copy of the world time zone map , ...

Detect Guide Directory


Outlined Time Zone Map of United States and Canada , Time ...
Visit Worldatlas.com for our outlined time zone map of Unites States, Canada and North America. Map of countries, facts, current date and time across North America. ...

North America Time Zone
Time zone and current times for all of the North America including information about daylight savings time and gmt

North America Map, North America Countries, Landforms, Rivers ...
North America maps, facts, and flags. Free maps of North American countries including our Mexico, Canada, and United States maps. Great geography information for students.

OnTimeZone.com North American Time Zones
( click on any map to see a full-size version suitable for printing) OnTimeZone.com provides borders for North American Time Zones including the ...

Revising North American Time Zones - Change Time Zones - Site Map
Maintain North America's A list of the pages in this site regarding time zone revision and daylight savings time.