To get credit for this Earthcache, you must attempt to answer all five questions
and send the answers through the GCHQ Message Center.
This Earthcache will take you to a roadcut and the southern end of a road that led to a bridge that washed out in the 1969 storms that devastated much of Southern California. You will learn how rock layering is used to determine its age. You may find it interesting to walk the tenth-of-a-mile walk along an old roadbed that will take you to the south end of the washed-out bridge. You can look at the soil makeup that might have contributed to the bridge's destruction there. Throughout the Earthcache, you will learn how JPSS measures weather data to predict and hopefully lessen the impact of increasing weather disasters.
Examining the Road Cut
Park at the posted coordinates and examine the walls of the roadcut as they relate to this information.
Before radiometric dating was discovered, geologists used relative dating to discuss the age of rocks. Relative dating looks at the position and location of the beds, or rock layers, relative to the other rocks, event markers, and known fossil ages. A few geologic rules are used to make assumptions as a relative dating process.
- The Law of Superposition states that age decreases from bottom to top in an undisturbed sequence of sediments or sedimentary rocks.
- The Principle of Original Horizontality states that sediment layers are generally deposited in a horizontal position. If layers are flat and relatively horizontal, they have not been disturbed.
- The Principle of Cross-Cutting Relationships- a rock or fault is younger than any rock or fault through which it cuts.
Question 1: Looking at the rock layers in the roadcut, which rules (1, 2, 3) apply?
Question 2: Is there an abundance of fossils that could be used to determine the age of the rocks? If there are, describe them.
Question 3: Starting at the base of the road cut and looking to the top, Do you see various types of rocks, or are the rocks essentially the same?
The nearby Earthcache, GC9DF2T, talks about diatomite, which is soft like chalk at that location. These rocks are also diatomite.
Question 4: Are these rocks harder or softer than chalk? Why do you think they are harder or softer than the chalk-like diatomite at GC9DF2T?
1969 Floods
Although not part of the Earthcache, it is interesting to walk down the old roadbed a tenth of a mile to visit the site of the washed-out bridge, here is some information about the floods of 1969.
The flood of 1969 was two distinct events – one the result of more than a week of rain in January 1969 and a subsequent flood from a second wave of rain in February. The damage from these storms was a statewide event, with 35 of 58 California counties declared federal disaster areas, the flood significantly impacted Santa Barbara County, including Lompoc.
It all began when a two-day storm on Jan. 13-14 brought rain totals in the area close to the annual normals. By Jan. 19, heavy rain and snow pelted the Southern California region. By Jan. 21, local newspapers called the area “water-logged” and drenched with the worst storm of the winter. Except for five days with no precipitation, the rain continued through January. On Jan. 26, 35 California counties were declared disaster areas.
The rain started falling again in the middle of February. The saturated soil could not hold any more water. All rain immediately became runoff. Areas that had suffered flooding at the end of January were again inundated with floodwater. With the ground already soaked, much more mud and mudslides came with the flooding.
Altogether, in January and February 1969, about 20-30 inches of precipitation fell in the lowlands and 50-60 inches in the mountains of Southern California, making 1969 the wettest year in recorded history up to that point.
CA Highway 1 and the Lompoc Drive-in
Photo credit: Lynn Brewer
Billion-Dollar Disasters
JPSS satellites provide sophisticated meteorological data and observations of the atmosphere, ocean, and land. NOAA's National Weather Service uses this data to increase the accuracy of forecasts three to seven days in advance of a severe weather event.
Meteorologists use data from the Advanced Technology Microwave Sounder (ATMS) and Cross-Track Infrared Sounder (CrIS) instruments to forecast weather and extreme storms. Sounding data makes up the largest data source in these models. Data from these instruments have improved the accuracy of weather forecasts and hurricane tracking since Suomi-NPP began flying in 2011. Our climate is changing, and instruments on the JPSS satellites, including JPSS-2, are helping scientists understand key factors, such as drought, the ozone hole, shifts in air quality, increases in severe weather, pollution, and more.
Billion-dollar weather events, disasters where overall damages/costs reached or exceeded $1 billion, are rising due to climate change. For the last seven years, the United States has experienced ten or more billion-dollar climate or weather disasters each year, with 20 billion-dollar disasters in 2021 alone.
Question 5: JPSS did not exist in 1969. When faced with the unprecedented amount of water inflow, the operators of the Bradbury Dam opened the gates to protect the dam and avoid complete disaster. If the same events occurred today, do you think the damage would be the same, less, or more? Why?
The codeword is on the first telephone pole west of the parking location.