How do geologists recognize gaps in the rock record?
What will be an ideal response?
Answer: Unconformities are former land or seafloor surfaces between rock layers that represent intervals not recorded in the local rock record. Angular unconformities separate sedimentary or volcanic rocks that are inclined at different angles. When an angular unconformity is present, the time required for tilting the lower rocks and eroding them to produce a new surface of deposition for the upper rocks is not represented in the geologic record. Disconformities separate sedimentary or volcanic rocks that are inclined at the same angle but are separated by an irregular erosion surface. This surface indicates a pause in deposition or erosion of the older rocks. Nonconformities separate sedimentary or volcanic rocks from underlying plutonic-igneous or metamorphic rocks. When a nonconformity is present, the time required to erode the materials that originally covered the plutonic and metamorphic rocks before the onset of the more recent sediment accumulation is not represented in the geologic record.
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The field of environmental science is considered interdisciplinary because it ____.
A. involves rigorous study of the environment B. includes topics that are not explored in other disciplines C. often assigns responsibility to those who cause environmental degradation D. is rapidly evolving over time into a different form of science E. incorporates work fromthe fields of biology, chemistry, geology, social sciences, and the humanities
Where are thunderstorms most common on Earth? In the United States?
What will be an ideal response?
The Sun stands directly above the equator ________.
A. once each year B. once in midsummer (Northern Hemisphere) C. once in midwinter (Northern Hemisphere) D. twice each year E. None of these is correct.
Match the country with the capital.
A) Uruguay B) Costa Rica C) Ecuador D) Cuba E) Peru F) Bolivia G) Paraguay H) Colombia I) Argentina J) Chile K) Nicaragua 64) Havana 65) Managua 66) San Jose 67) Bogotá 68) Quito 69) Lima 70) La Paz 71) Santiago 72) Buenos Aires 73) Montevideo 74) Asuncion