Certified Engineering Geologist 125 Exam
Questions and Verified Answers Rationales 2026 |
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1. Which of the following soil types is most susceptible to liquefaction
during an earthquake?
A) Dense sand
B) Loose, saturated sandy soil
C) Clay
D) Bedrock
Explanation: Loose, water-saturated sands lose strength under seismic
shaking, causing liquefaction.
2. Which factor is MOST important when evaluating foundation bearing
capacity?
A) Soil color
B) Soil type, density, and moisture content
C) Surface vegetation
D) Nearby structures
Explanation: The type and condition of the soil determine its ability to
support structural loads.
3. In engineering geology mapping, which scale is typically preferred for
detailed site investigations?
A) 1:250,000
B) 1:24,000
,C) 1:1,000,000
D) 1:2,500,000
Explanation: 1:24,000 scale (7.5-minute quadrangle) provides sufficient
detail for site-specific evaluations.
4. Which soil property is MOST relevant for slope stability analysis?
A) Soil color
B) Soil texture only
C) Cohesion, internal friction angle, and unit weight
D) Soil odor
Explanation: Shear strength parameters (cohesion and friction) determine
slope stability.
5. During a geologic field investigation, the term “RQD” refers to:
A) Regional Quaternary Deposits
B) Rock Quality Designation
C) Residual Quartz Density
D) Regional Quaternary Depth
Explanation: RQD is a measure of intact core recovery used to assess rock
quality.
6. Which of the following is a primary concern for expansive clay soils?
A) Low permeability
B) Shrink-swell potential affecting foundations and pavements
C) High density
D) Liquefaction risk
,Explanation: Expansive clays expand when wet and shrink when dry,
damaging structures.
7. Which field test is commonly used to determine in-situ soil density?
A) Standard Penetration Test (SPT) only
B) Sand cone or nuclear density test
C) Atterberg limits
D) Grain size analysis
Explanation: Sand cone and nuclear density tests measure the density of
soils in place.
8. Which soil property most directly influences slope stability?
A) Plasticity index
B) Color
C) Shear strength parameters (cohesion and internal friction angle)
D) Particle shape
Explanation: Shear strength determines the soil’s ability to resist sliding.
9. Which geologic material is generally considered the most stable for
foundation support?
A) Loose sand
B) Soft clay
C) Bedrock
D) Fill soil
Explanation: Bedrock provides the highest bearing capacity and minimal
settlement.
, 10. When conducting a subsurface investigation, which method provides
continuous rock and soil profiles?
A) Test pits
B) Cone penetration test
C) Drilled boreholes with core sampling
D) Surface mapping
Explanation: Boreholes allow collection of continuous core for
stratigraphic and engineering analysis.
11. The primary purpose of a Standard Penetration Test (SPT) is to:
A) Measure groundwater chemistry
B) Estimate relative density and strength of granular soils
C) Determine clay plasticity
D) Map geologic units
Explanation: SPT results provide an index of soil strength and density.
12. Which of the following best describes residual soils?
A) Transported by water or wind
B) Formed in place from weathered bedrock
C) Artificial fill
D) Marine deposits
Explanation: Residual soils develop from in-situ weathering of underlying
rock.
13. Which soil test is used to classify fine-grained soils by plasticity?
A) Sieve analysis
B) Standard Penetration Test
Questions and Verified Answers Rationales 2026 |
Instant Download Pdf
1. Which of the following soil types is most susceptible to liquefaction
during an earthquake?
A) Dense sand
B) Loose, saturated sandy soil
C) Clay
D) Bedrock
Explanation: Loose, water-saturated sands lose strength under seismic
shaking, causing liquefaction.
2. Which factor is MOST important when evaluating foundation bearing
capacity?
A) Soil color
B) Soil type, density, and moisture content
C) Surface vegetation
D) Nearby structures
Explanation: The type and condition of the soil determine its ability to
support structural loads.
3. In engineering geology mapping, which scale is typically preferred for
detailed site investigations?
A) 1:250,000
B) 1:24,000
,C) 1:1,000,000
D) 1:2,500,000
Explanation: 1:24,000 scale (7.5-minute quadrangle) provides sufficient
detail for site-specific evaluations.
4. Which soil property is MOST relevant for slope stability analysis?
A) Soil color
B) Soil texture only
C) Cohesion, internal friction angle, and unit weight
D) Soil odor
Explanation: Shear strength parameters (cohesion and friction) determine
slope stability.
5. During a geologic field investigation, the term “RQD” refers to:
A) Regional Quaternary Deposits
B) Rock Quality Designation
C) Residual Quartz Density
D) Regional Quaternary Depth
Explanation: RQD is a measure of intact core recovery used to assess rock
quality.
6. Which of the following is a primary concern for expansive clay soils?
A) Low permeability
B) Shrink-swell potential affecting foundations and pavements
C) High density
D) Liquefaction risk
,Explanation: Expansive clays expand when wet and shrink when dry,
damaging structures.
7. Which field test is commonly used to determine in-situ soil density?
A) Standard Penetration Test (SPT) only
B) Sand cone or nuclear density test
C) Atterberg limits
D) Grain size analysis
Explanation: Sand cone and nuclear density tests measure the density of
soils in place.
8. Which soil property most directly influences slope stability?
A) Plasticity index
B) Color
C) Shear strength parameters (cohesion and internal friction angle)
D) Particle shape
Explanation: Shear strength determines the soil’s ability to resist sliding.
9. Which geologic material is generally considered the most stable for
foundation support?
A) Loose sand
B) Soft clay
C) Bedrock
D) Fill soil
Explanation: Bedrock provides the highest bearing capacity and minimal
settlement.
, 10. When conducting a subsurface investigation, which method provides
continuous rock and soil profiles?
A) Test pits
B) Cone penetration test
C) Drilled boreholes with core sampling
D) Surface mapping
Explanation: Boreholes allow collection of continuous core for
stratigraphic and engineering analysis.
11. The primary purpose of a Standard Penetration Test (SPT) is to:
A) Measure groundwater chemistry
B) Estimate relative density and strength of granular soils
C) Determine clay plasticity
D) Map geologic units
Explanation: SPT results provide an index of soil strength and density.
12. Which of the following best describes residual soils?
A) Transported by water or wind
B) Formed in place from weathered bedrock
C) Artificial fill
D) Marine deposits
Explanation: Residual soils develop from in-situ weathering of underlying
rock.
13. Which soil test is used to classify fine-grained soils by plasticity?
A) Sieve analysis
B) Standard Penetration Test
