NCEA Level 1 Science (90190) 2009 — page 1 of 5 Assessment Schedule – 2009 Science: Describe aspects of geology (90190) Evidence Statement Q ONE (a) Achievement (Statements) Merit (Explanations) Excellence (Expanded explanations) Correct statement. Pumice: light coloured or yellow very low density full of gas holes crumbles and breaks easily small crystals / fine grained. OR Obsidian: black / brown colour Higher density glassy (fractures) breaks with sharp edges (fractures) no crystals. (b) Q1 Judge Correct statement to do with formation. Explains feature in terms of formation. Discusses formation of both rocks and links their physical features to formation. Eg: Pumice / obsidian cools quickly. OR Pumice is from silica-rich lava. OR Pumice has a high gas content. OR Pumice / Obsidian is formed outside of a volcano / extrusive. OR Pumice is formed from explosively blown out material (pyroclastic). OR Obsidian is cooled quickly. OR Obsidian is from silica rich lava. OR Obsidian has low / no gas content. OR Obsidian is formed from highly viscous lava / erupted quietly. Eg: Pumice is rich in silica, hence the light colour. OR Pumice is explosively blown into the air (pyroclastic) forming gas holes. OR Obsidian is cooled quickly leading to no crystals. OR Obsidian is formed from low gas content therefore it has a greater density. Eg: Pumice is rich in silica, hence the light colour, explosively blown into the air (pyroclastic). This results in rock being highly gaseous, and low density. It is fine grained as it cools rapidly. Obsidian is erupted (quietly) from a volcano rich in silica, as a thick (highly viscous) sluggish lava flow. Therefore low gas content leading to greater density. It cools so quickly that no crystals form. 3a=A from (a) or (b) 2m=M 1e=E NCEA Level 1 Science (90190) 2009 — page 2 of 5 TWO Correct statement AND rock named. (a) Example 1: Lithification Weathering and erosion / transport. OR Compaction and cementing of sediment. OR Lithification of sediment. OR Layers formed in deep water environment. AND One rock named. Example 2: Metamorphism Heat and pressure. OR Original rock is deeply buried / subducted / plate tectonics pushes the rock down. OR Regional metamorphism and pressure. OR Contact metamorphism and heat. OR Recrystallisation / chemical altering. AND One rock named Example 3: Melting Rocks melt due to high temperatures / extreme heat (+ pressure). OR Subduction and heat / friction. OR Melted by / turned into magma / mantle. OR Original rock is melted with different combinations of (minerals) in new rock. AND One rock named. Q2 Judge 1a=A Correct statement about a named rock AND explains the process. (m) Correct statement about a named rock AND fully discusses the process. (e) Example 1: Lithification – explains that rock is weathered and eroded / transport OR Lithification –compacted and cemented (over millions of years). AND One rock named Example 1: Lithification – explains that rock is weathered and eroded and turns into sediment which is then deposited by size. The sediment is then compacted and cemented over millions of years. Example 2: Metamorphism –deeply buried / subduction for metamorphism to occur. OR Metamorphism - existing rock undergoes extreme heat and pressure causing the rock to change its characteristics. AND One rock named. Example 3: Melting – rocks are subducted and due to increased temperatures / extreme heat, melt. AND One rock named AND Start and finish rock named. Eg andesite – conglomerate Example 2: Metamorphism - Continued deep burial / subduction / plate tectonics pushes the rock to depths sufficient for rocks to be changed / recrystallise / chemically alter by heat and pressure. AND Start and finish rock named. Eg limestone to marble Eg granite – gneiss Eg shale / mudstone / claystone to slate / schist / gneiss Eg coal to bitumous coal Example 3: Melting – explains that rocks are pushed down by plate tectonic processes (subduction) to depths where temperatures and pressures are high enough to remelt the rock into liquid magma. Original rock is melted with different combinations of (minerals) in new rock. AND Start and finish rock named linking any metamorphic rock to any igneous rock. 1m=M 1e=E NCEA Level 1 Science (90190) 2009 — page 3 of 5 THREE Describe geological event / process or environment relating to a rock formation. Eg: Explains TWO geological events / processes and environments relating to a rock formation. Eg: Relates or Justifies consecutive geological events / processes and environments in relation to the rock formations. Eg: NCEA Level 1 Science (90190) 2009 — page 4 of 5 Q3 Judge States that the fault is older than the coal seam. OR Folded layers are the oldest. OR Folded / tilted due to plate tectonic movement. OR Coal forms in a swampy area. OR Deposition at different times OR Uneven surface due to erosion. OR Layers formed underwater. OR Faults caused by tectonic movement. OR Uplift of land by tectonic movement. The fault is younger than the tilted layers and folded layers. OR Deposition of sediments occurs underwater. The layers are then folded / tilted. OR Layers are folded and tilted then movement on the fault line occurs. OR Land sinks then coal is deposited. Rock layers require land to be eroded so sediments are formed for deposition. OR Layers (of sedimentary rock) formed before uplift / tilting / folding because they are horizontal when they are formed in water. OR Tectonic plate movement / subduction / converging plates caused layers to fold. OR Folded layers are older than the tilted one because they are moving up and the tilted layer is moving down. OR The layers (under coal) must have been uplifted to bring layers above water so erosion could occur. OR Erosion occurs after tilting because of unconformity / incomplete layers. OR Tilted / folding occurs before coal is deposited because it is horizontal / flat / cut across layers. OR For another (sedimentary) rock to form above coal, land must have sunk. OR All layers must have been uplifted for the surface to be eroded. OR Tectonic plate movement / subduction causes uplift. 2a=A 2m=M 2e=E NCEA Level 1 Science (90190) 2009 — page 5 of 5 QUESTION THREE Full sequence of events: • Layers form below sea level from sediment • Then folded / tilted • Then faulting, moving RHS up and LHS down • Then erosion • Then eroded down / sinks to esturine swamp environment • Then coal material deposited • Then sinks below sea and top layer deposited • All layers uplifted • Then further erosion. Judgement Statement Achievement Achievement with Merit Achievement with Excellence 2 A or above 1A 1M 1M 1E Lower case a, m, e may be used throughout the paper to indicate contributing evidence for overall grades for questions. Only the circled upper case A, M and E grades shown at the end of each full question are used to make the final judgement.