Trust Your Driller!

Oil/Gas and water well drillers are brought up in their trade/profession with a lot of apprenticing experience.  In addition to operating and maintaining their great or small drilling machines, they use tested and handed-down means of describing formations that they drill.

Today, I want to call attention to water well drillers' descriptions of how fast and in what way their drill bits progress through parts of formations.  My example is from the Willamette Valley of Oregon, USA.

When the driller of the Fairview School Well, a few miles southeast of the State Capitol, drilled soil and rock formations in this well, he used three speed terms; Soft, Moderate and Hard.  Soft means that the drill bit was not resisted greatly and he had fast drilling.  This drilling rate, in Oklahoma Oil/Gas drilling charts would be about 1-2 minutes per foot, or a penetration rate of greater than fifty feet an hour.  Moderate or "Medium" means that drilling is going at an average and the drill bit is meeting some resistance in drilling.  This would be common of a lightly cemented sand and gravel or a rock.  The drilling rate would be 3 to 5 minutes per foot or a penetration rate of 10 to 20 feet per hour.   Hard drilling means that the drill bit is meeting a lot of resistance.  Simply put, the rock is very hard.  The drilling rate is 8 to 12 minutes or more per foot, or less than 10 feet per hour as a penetration rate.  Directional drillers in oil and gas work would consider "tripping the bit" (pulling out of the hole, thousands of feet and changing the drill bit), but water wells are more shallower enterprises and water well drillers wait.

In the oil boom of the 1980s, I learned with Gulf Oil in Oklahoma that plotted drilling rate could mimic the Gamma Ray (GR) Correlation Curve that oil and gas geologists used from downhole geophysical logs.  We combined our sample logs with the GR curve to find how deep the drill was and to evaluate reservoir quality of formations.  Drill Time and the driller's rock descriptions (left column) reveal good qualities below the Shale (Depth 173', Elevation +37 ') that enabled the well to produce 380 gallons per minute with 72 feet of drawdown.  That is a good well.  The "drilling breaks", where the drilling gets "soft" or faster are where the lava flow tops are vesicular. There is "porosity" in the breaks.  With a little tectonically-imparted fracturing the vesicles become interconnected and provide good pathways to the open borehole.

The Importance of the Practice of Geology in Oregon, A Visit to Radio Station KMUZ FM 88.5

I visited this local radio station in Salem, Oregon at Noon, Today, to speak about Geology in Oregon.  My purpose was to connect listeners to the geological structures that they have been walking over unawares. All of us go about our day, seeing strangers going by in their cars, cashiers at the grocery store, produce grocers, their co-workers at the office and family members.

During our 40 minute radio question-answer talk, I explained that that the western landscape was composed of sloping rocks of hard lava flows that had been jostled around by great earth forces that shoved parts of the Pacific Ocean bottom past and under North America.  Two local results were the Willamette Valley (home of Salem, Oregon) and the Cascade Mountain Range (where we see Volcanoes on the eastern skyline).

The hills around the valley downtown of Salem were tilted by these regional forces.  The Salem Hills, south of the city, tilt toward it from Chinook Estates and Prospect Peak.  The Amity Hills of West Salem, tilt northeast to the Willamette River.

This talk was the beginning effort to make geology familiar to the people of Salem, so that on foot and in their cars, they may be connected to their physical environment. The KMUZ host, Ken Adams, and I hope that the public gets "outside" to understand local geology.

A President's Day Radio Show with John Rehm about Geology at KMUZ 88.5FM

On Monday, February 17th, I will visit KMUZ Talk Radio Host, Ken Adams at his studio in Salem.  Our talk is at Noon until 12:30PM.   

Listen in by going to KMUZ 88.5FM on Facebook or tweet me @StoutHammer.  You can call in by a local Salem phone number to our talk at 503-990-6101.

We will talk about why geology is important to any town or city.  The talk will range across some of the topics in my following biographical sketch for the talk show host:

"I have been in business in Geology in Salem since 1992.  I have been here since 1985 when I went to work for the Oregon Water Resources Department.  I am from a small town in New Jersey where I used to fish for trout in the creeks, sled in the woods and walk the open fields with my dog and shotgun.  I had married and gone to Oklahoma by the time my town got built up and all of that changed. 

I got very interested in geology while at college at Lafayette College in Easton, Pa.  The geology department was small like the earth science department, now at Western Oregon University.  I know the geologists there and taught Physical Science labs at Western in 2001 and 2002.

When I was a student, I was thrilled by the giant earth processes of volcanoes, earthquakes, floods and continental ice sheets. I was shocked by the overwhelming speed and power of these events. Few can outpace a volcanic ashflow. No one can stand its 1000 degree temperature. 

What I like about Geology is being outside.  You have an office, but you have to get outside to get your information. Geologists are needed for building new office parks and highway bridges.  A few are needed for watching our Cascade Volcanoes.  Others are needed for building or adding onto water well fields.  I work with farmers who have irrigation wells.  In Salem, geologists work for the Oregon Department of Transportation, near the Highway.  There are geologists at the Oregon Water Resources Department and a few work at the downtown DEQ office, not far from your radio station studio.

Geology is a science, but because it deals with ever changing natural processes it is also storytelling.  At their best, our reports are clear storytelling with concise information, lodged in tables of information and scaled drawings.  Geologists go on field trips, where a group of them travels around a wide region to look at rocks and to figure them out.  You see, valley and mountain shapes are determined by troughs, folds and faults of rock layers, whether these rocks were molten or sedimentary.  On some evenings, geologists may gather around campfires and describe their findings, but also share stories about how they climbed a mountain to get a great view.

Geologists may describe a fossil or a mineral specimen. Some of the fossils in a rock, here in the valley, look like the clams and snails that live in the sand of the bays and beaches of the Oregon Coast.  Some are a little different, such as the partly uncoiled snails. Geologists can show with their hands how rock layers angle down the west wide of the Cascades into the Willamette Valley and are pushed up around Salem. They can show the side to side jostling of faults coming in from the Pacific Ocean and the up-to-down movement of faults."