OSAT Earth Science (OK108) study plan

Distinguish the diagnostic properties of the major mineral groups (silicates, carbonates, oxides, sulfides, sulfates, halides) and classify 20 hand specimens or labeled descriptions by those properties.

Diagram the rock cycle and explain at least three pathways by which a sedimentary or metamorphic rock can return to magma, naming the processes at each arrow.

Differentiate the three plate boundary types by their relative motion, associated seismic style (shallow versus deep focus), and characteristic volcanic products.

Sketch a cross section of Earth's interior labeling crust, lithosphere, asthenosphere, mesosphere, outer core, and inner core, and state the evidence (seismic velocities, S-wave shadow zone, density) supporting each boundary.

Interpret block diagrams to identify folds (anticline, syncline, monocline) and faults (normal, reverse, strike-slip) and justify each identification from the geometry of the beds.

Apply the principles of superposition, original horizontality, lateral continuity, cross-cutting relationships, and faunal succession to determine the relative order of at least five labeled rock units and one intrusion.

Explain how magnetic striping and seafloor age patterns support seafloor spreading, and calculate a spreading rate given a distance and an age.

Correlate stratigraphic columns from two localities and identify a disconformity, an angular unconformity, and a nonconformity in described sequences.

Explain how solar radiation, latitude, albedo, and the greenhouse effect combine to produce the global energy balance, and predict how a change in one factor shifts surface temperature.

Read a station model and a surface weather map to state temperature, dew point, pressure tendency, wind direction and speed, and the location of fronts.

Describe the formation and life cycle of a midlatitude cyclone and contrast it with a thunderstorm and a tropical cyclone in terms of energy source and scale.

Distinguish mechanical from chemical weathering and predict which will dominate under given climate and rock-type conditions.

Explain how soil profiles (O, A, E, B, C horizons) develop and how parent material, climate, topography, organisms, and time control soil properties.

Explain the causes of seasons, tides (spring versus neap), eclipses, and Moon phases using a labeled orbital diagram, and predict the phase or tide type from a given Sun-Earth-Moon geometry.

Describe Earth's orbital parameters (eccentricity, obliquity, precession) and explain how each contributes to long-term climate variation.

Trace the path of a water parcel through the hydrologic cycle and quantify the relative sizes of the ocean, groundwater, glacier, and surface-water reservoirs.

Explain thermohaline circulation, upwelling, and the Coriolis effect, and predict how each influences coastal climate or marine productivity.

Distinguish the components of the cryosphere and describe at least two feedback mechanisms involving ice and albedo.

Design a controlled investigation for an Earth science question, explicitly identifying independent, dependent, and controlled variables, a control group, and sources of error.

Construct and interpret a graph or map from raw Earth science data and state a conclusion supported by specific values.

Evaluate the difference between a hypothesis, a theory, and a law using an Earth science example, and identify when new evidence should revise a model.

Write a lab safety plan for a classroom activity involving rock samples, dilute acid tests, and stream-table work, naming hazards, PPE, and disposal procedures.

Draft three assessment items (one multiple choice, one constructed response, one performance task) aligned to a single Earth science standard and include a scoring rubric for the constructed response.

Classify sedimentary rocks by texture and composition and interpret depositional environments from grain size, sorting, rounding, and sedimentary structures.

Distinguish foliated from nonfoliated metamorphic rocks and relate metamorphic grade to temperature, pressure, and plate tectonic setting.

Explain the processes of erosion, transport, and deposition by water, wind, ice, and gravity, and predict the landforms each produces.

Interpret a topographic map to calculate gradient, identify drainage divides, and describe stream-channel characteristics from contour spacing.

Explain mass wasting types and the factors (slope angle, water content, vegetation, geology) that trigger them.

Build a scaled geologic time line placing the major eons, eras, and periods and marking at least six key events, including mass extinctions and their proposed causes.

Explain how index fossils and radiometric dating are combined to construct the geologic time scale, and calculate a radiometric age from a decay curve.

Interpret a climate data set (temperature or CO2 proxy) to identify trends, natural variability, and the role of anthropogenic forcing.

Explain El Nino-Southern Oscillation and its effects on global precipitation and upwelling, and contrast it with La Nina.

Describe ocean acidification and its mechanism, and connect it to atmospheric carbon dioxide and marine calcifiers.

Complete two full-length timed practice tests under exam conditions and record the score, timing, and error pattern for each domain.

Re-teach your five weakest concepts by writing a plain-language explanation and a worked example for each, without referring to notes.

Review every missed item from weeks 1-7 and confirm you can state the correct reasoning in one sentence.

Assemble a one-page formula and reference sheet (spreading rate, gradient, radiometric decay, reservoir percentages, boundary types) and verify each entry against a reliable source.