CurriculumGrade 12Science

Building Landforms Over Time

Aligned to HS-ESS2-1 — Next Generation Science Standards.

What this lesson teaches

Landforms result from a tug-of-war between internal processes that build up the crust and surface processes that wear it down. These act on very different scales: a mountain rises over millions of years, but a flash flood can reshape a canyon in hours.

Worked example

The Himalayas rise a few millimeters each year as India collides with Asia, a slow internal process. Meanwhile, rivers and glaciers carve valleys into them far faster, so the peaks we see reflect the balance between uplift and erosion.

Practice questions

  1. Observe: Some landforms take millions of years to form while others change in a single storm. What does that range in timescale tell you about the processes involved?
  2. Model: Draw a mountain and label one internal process building it up and one surface process wearing it down.
  3. Explain: A mountain range stops rising but erosion continues. Predict how its shape changes over the next million years and explain why.

Watch the lesson

Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.

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En español

Formación del relieve en el tiempo

El relieve resulta de un forcejeo entre procesos internos que levantan la corteza y procesos superficiales que la desgastan. Actúan a escalas muy distintas: una montaña se eleva a lo largo de millones de años, pero una inundación repentina puede remodelar un cañón en horas.

Ejemplo: El Himalaya se eleva unos milímetros cada año a medida que India choca con Asia, un proceso interno lento. Mientras tanto, los ríos y glaciares tallan valles mucho más rápido, así que los picos que vemos reflejan el equilibrio entre el levantamiento y la erosión.

More Earth's Systems lessons

Feedbacks Between Earth SystemsHS-ESS2-2Convection in the MantleHS-ESS2-3Water Shapes Earth's SurfaceHS-ESS2-5The Carbon CycleHS-ESS2-6Coevolution of Life and EarthHS-ESS2-7

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