{ "schema": 1, "pack_id": "canyon-puzzles", "title": "Canyon Puzzles", "evidence_class": "illustrative", "notice": "Original teaching drawings inspired by Bryce. Shapes, coordinates and dimensions are invented for these activities; they do not describe surveyed places or routes.", "categories": [ {"id":"contours","label":"Read the land","skill":"Contours"}, {"id":"viewpoints","label":"Turn your viewpoint","skill":"Orientation"}, {"id":"scale","label":"Think in scale","skill":"Scale"}, {"id":"layers","label":"Read the layers","skill":"Relative time"}, {"id":"shadows","label":"Follow the light","skill":"Shadows"}, {"id":"evidence","label":"Question the evidence","skill":"Evidence"} ], "puzzles": [ { "id":"bcc-cp-01","number":1,"category":"contours","title":"A hill, seen two ways", "lead":"A contour map is a landscape viewed from above. Can you imagine its profile?", "prompt":"Follow the dashed line from west (W) to east (E). Which profile fits the contours?", "assumptions":"Each contour is 10 model units higher than the last. The unmarked summit is just inside the 40-unit loop. Profiles are schematic.", "kind":"choice", "options":[{"id":"a","label":"A · Steep west side, gentle east side"},{"id":"b","label":"B · Gentle west side, steep east side"},{"id":"c","label":"C · A hollow, lowest in the middle"}], "answer":{"values":["b"]}, "hint":"Compare how far you travel between equal height steps on each side.", "retry":"Look at the spacing, as well as whether the numbers increase or decrease toward the center.", "explanation":"B fits. On the west, each 10-unit climb takes a longer horizontal distance. On the east, the same climb is squeezed into less space. The labels increase inward, so the center is a hill, not a hollow.", "takeaway":"Close contour spacing means a steeper slope when the contour interval and map scale are the same.", "figure":{"kind":"contour-profile","file":"figures/01-contour-profile.svg","title":"Contours and three candidate profiles","description":"Four nested contours are labeled 10, 20, 30 and 40. Along the west-to-east center line their west intersections are at 60, 160, 260 and 360; east intersections are at 560, 510, 460 and 410. Profile A climbs steeply on the west; B climbs gently on the west; C is a hollow.","model":{"levels":[10,20,30,40],"west":[60,160,260,360],"east":[560,510,460,410]}}, "source_ids":["cp-usgs-contours","cp-original"] }, { "id":"bcc-cp-02","number":2,"category":"contours","title":"One line, one height", "lead":"Two dots can be far apart on the page and still share a height.", "prompt":"Which two statements are supported by the labeled contour lines? Select both.", "assumptions":"Dots sit exactly on the contours. Heights are invented model units, with a 10-unit interval.", "kind":"multi", "options":[{"id":"equal","label":"A and B have the same elevation."},{"id":"higher","label":"C is 20 units higher than A."},{"id":"distance","label":"A and B are 30 units apart horizontally."},{"id":"lower","label":"C is lower because it is nearer the center."}], "answer":{"values":["equal","higher"]}, "hint":"A contour number describes height, not distance along the line.", "retry":"Read the line under each dot. Then distinguish height from horizontal distance.", "explanation":"A and B both lie on the 30-unit contour. C lies on the 50-unit contour, so it is 20 units higher. A contour label gives no horizontal distance between A and B.", "takeaway":"A contour connects equal elevations. Its shape is not a ruler.", "figure":{"kind":"equal-contours","file":"figures/02-equal-contours.svg","title":"Three points on a contour hill","description":"A and B sit on opposite sides of the same contour, labeled 30. C sits on the innermost contour, labeled 50. Outer contours are 10 and 20; the line between 30 and 50 is 40.","model":{"a":30,"b":30,"c":50}}, "source_ids":["cp-usgs-contours","cp-original"] }, { "id":"bcc-cp-03","number":3,"category":"viewpoints","title":"Look north, read left", "lead":"The map stays still. Your point of view changes what left and right mean.", "prompt":"At the south marker, you face north. What is the left-to-right order of the three pillars?", "assumptions":"This is a plan view, with north at the top. Use the lettered centers; all three pillars are visible.", "kind":"choice", "options":[{"id":"abc","label":"A → B → C"},{"id":"cba","label":"C → B → A"},{"id":"bac","label":"B → A → C"}], "answer":{"values":["abc"]}, "hint":"When you face north, which compass direction is on your left?", "retry":"Place yourself at the south arrow and face toward the top of the plan.", "explanation":"A → B → C. Facing north puts west on your left and east on your right. A is west of B, and C is east of B. Facing south would reverse the order.", "takeaway":"A north arrow describes the map. Left and right belong to the viewer.", "figure":{"kind":"plan-north","file":"figures/03-plan-north.svg","title":"A north-up plan of three invented pillars","description":"A is at east -2, north -1; B at east 0, north 1; C at east 2, north -1. The viewer is south of them, looking north. North is up, east is right.","model":{"pillars":[{"id":"A","east":-2,"north":-1,"height":3},{"id":"B","east":0,"north":1,"height":5},{"id":"C","east":2,"north":-1,"height":4}],"view":"north"}}, "source_ids":["cp-original"] }, { "id":"bcc-cp-04","number":4,"category":"viewpoints","title":"Hidden behind a neighbor", "lead":"A new viewpoint can hide a feature that is obvious on a map.", "prompt":"Look east from the west marker. Which two pillar centers line up, one behind the other?", "assumptions":"Use a parallel (orthographic) view: sight lines run due east. Compare centers, not widths or whether a taller top remains visible.", "kind":"choice", "options":[{"id":"ab","label":"A and B"},{"id":"ac","label":"A and C"},{"id":"bc","label":"B and C"}], "answer":{"values":["ac"]}, "hint":"Draw a straight east–west line through each center.", "retry":"In this view, pillars line up when they have the same north–south position.", "explanation":"A and C share the same north–south position. Looking due east, A is nearer and C is behind it. B sits farther north, so its center appears to the left of theirs. This does not mean C’s entire silhouette disappears.", "takeaway":"One view cannot show every surface. An overlap is not evidence that the hidden object is absent.", "figure":{"kind":"plan-east","file":"figures/04-plan-east.svg","title":"The same three pillars, viewed from the west","description":"A is at east -2, north -1; B at east 0, north 1; C at east 2, north -1. The viewer is west of A, looking due east. A and C have equal north coordinates.","model":{"pillars":[{"id":"A","east":-2,"north":-1,"height":3},{"id":"B","east":0,"north":1,"height":5},{"id":"C","east":2,"north":-1,"height":4}],"view":"east"}}, "source_ids":["cp-original"] }, { "id":"bcc-cp-05","number":5,"category":"scale","title":"Borrow the scale bar", "lead":"A scale bar gives a drawing a size in the world it represents.", "prompt":"The pillar’s drawn height is three times the length of the 4 m scale bar. How tall is the model pillar?", "assumptions":"This is a side-on scale drawing with equal horizontal and vertical scale. The dimension is invented, not a measured Bryce hoodoo.", "kind":"number","unit":"m", "answer":{"number":12,"tolerance":0.000001}, "hint":"Each one of the three equal lengths represents 4 metres.", "retry":"Multiply the number of scale-bar lengths by the metres represented by one bar.", "explanation":"3 × 4 m = 12 m. The vertical guide and horizontal bar use the same scale. The answer stays 12 m if the whole diagram is enlarged uniformly.", "takeaway":"Use the scale relationship, not a ruler on your screen.", "figure":{"kind":"scale-height","file":"figures/05-scale-height.svg","title":"An invented pillar with a scale bar","description":"The pillar’s height spans three equal 72-unit drawing intervals, for a total of 216 drawing units. A horizontal bar 72 drawing units long represents 4 metres.","model":{"height_pixels":216,"bar_pixels":72,"bar_metres":4}}, "source_ids":["cp-usgs-contours","cp-original"] }, { "id":"bcc-cp-06","number":6,"category":"scale","title":"Bigger on paper", "lead":"Enlarging a drawing changes the ink, not the landscape it represents.", "prompt":"Drawing B is a 150% enlargement of A, including its scale bar. Which two statements are true?", "assumptions":"A and B show the same invented ridge. Both are uniformly scaled, with no cropping or added measurements.", "kind":"multi", "options":[{"id":"same","label":"Both drawings represent an 80 m span."},{"id":"bar","label":"B’s longer printed scale bar still represents 20 m."},{"id":"grows","label":"The represented ridge grows to 120 m in B."},{"id":"detail","label":"B reveals newly measured rock detail."}], "answer":{"values":["same","bar"]}, "hint":"Count scale bars across the span in each drawing.", "retry":"A larger copy adds no new measurements. Compare the ridge with its own scale bar.", "explanation":"Each ridge spans four of its own 20 m bars: 4 × 20 = 80 m. B’s ridge and bar are both 1.5 times as long on the page. Enlarging existing marks cannot recover detail that was never recorded.", "takeaway":"A bar scale survives uniform resizing when it resizes with the drawing.", "figure":{"kind":"scale-resize","file":"figures/06-scale-resize.svg","title":"Two sizes of the same ridge drawing","description":"Drawing A has a ridge span of 200 drawing units and a 50-unit bar labeled 20 m. B has a 300-unit span and a 75-unit bar also labeled 20 m. B is 150 percent of A.","model":{"a":{"span":200,"bar":50},"b":{"span":300,"bar":75},"bar_metres":20}}, "source_ids":["cp-usgs-contours","cp-original"] }, { "id":"bcc-cp-07","number":7,"category":"layers","title":"The oldest goes first", "lead":"Rock layers hold a relative order, even when their ages are unknown.", "prompt":"Put the layers in order of deposition, from oldest to youngest. Use the up and down buttons.", "assumptions":"These four sedimentary layers are undisturbed and have not been overturned. Letters identify invented layers, not named Bryce formations.", "kind":"order", "options":[{"id":"c","label":"C · dotted top layer"},{"id":"a","label":"A · dashed layer"},{"id":"b","label":"B · striped layer"},{"id":"d","label":"D · pebbly base layer"}], "answer":{"values":["d","b","a","c"]}, "hint":"Which layer was already there when the next one was laid on top?", "retry":"Start at the base and read upward. Letter order is not time order.", "explanation":"D → B → A → C. Under the stated conditions, a lower sedimentary layer was deposited before the layer above it. This gives a sequence, not ages in years or the duration of any gaps.", "takeaway":"Relative time tells us before and after; it does not supply a date.", "figure":{"kind":"layer-order","file":"figures/07-layer-order.svg","title":"Four undisturbed teaching layers","description":"A cutaway block shows four horizontal layers. From top to bottom they are C with dots, A with dashes, B with stripes, and D with pebble shapes. The block has not been overturned.","model":{"bottom_to_top":["d","b","a","c"]}}, "source_ids":["cp-nps-superposition","cp-nps-hoodoos","cp-original"] }, { "id":"bcc-cp-08","number":8,"category":"layers","title":"The missing middle", "lead":"A gap is a clue. It may have more than one explanation.", "prompt":"Layer B is missing from the right record. Which two histories could explain this? Select both possibilities.", "assumptions":"The matching A and C layers have already been correlated. Both records are upright. No other evidence about B is available.", "kind":"multi", "options":[{"id":"eroded","label":"B formed on the right, then eroded before C was deposited."},{"id":"absent","label":"B was never deposited on the right."},{"id":"younger","label":"A must be younger than C on the right."},{"id":"years","label":"Exactly one million years is missing on the right."}], "answer":{"values":["eroded","absent"]}, "hint":"Think about the difference between something removed and something never put down.", "retry":"Choose plausible histories, not a single story that the diagram cannot prove.", "explanation":"Either B was removed before C arrived, or B was not deposited there. The two simplified records cannot decide between those histories or tell us how much time is missing. More evidence is needed.", "takeaway":"An incomplete record can support multiple explanations. Keep them open until evidence distinguishes them.", "figure":{"kind":"missing-layer","file":"figures/08-missing-layer.svg","title":"Two simplified layer records","description":"The left record contains A at the base, B in the middle, and C on top. The right record has A directly beneath C and no B. Equal letters are stipulated to be matching layers; thickness is not a time scale.","model":{"left_bottom_to_top":["a","b","c"],"right_bottom_to_top":["a","c"]}}, "source_ids":["cp-nps-gaps","cp-original"] }, { "id":"bcc-cp-09","number":9,"category":"shadows","title":"Find the light", "lead":"A shadow points away from the light that made it.", "prompt":"The pillar’s shadow extends northeast. From which direction does the light arrive?", "assumptions":"The diagram is north-up, on level ground, with one distant light source. No calendar date or time of day is implied.", "kind":"choice", "options":[{"id":"nw","label":"Northwest"},{"id":"ne","label":"Northeast"},{"id":"se","label":"Southeast"},{"id":"sw","label":"Southwest"}], "answer":{"values":["sw"]}, "hint":"Continue the shadow line backward through the pillar.", "retry":"The illuminated side faces the source; the shadow extends to the opposite side.", "explanation":"Southwest. Reverse the northeast shadow direction by half a turn. This answers the drawing’s geometry; it does not establish a time of day at Bryce.", "takeaway":"Direction can be inferred from a shadow only within stated lighting and surface assumptions.", "figure":{"kind":"shadow-direction","file":"figures/09-shadow-direction.svg","title":"A northeast shadow on a compass plan","description":"A pillar is centered in a north-up compass diagram. Its clearly labeled shadow extends toward northeast, between north and east.","model":{"shadow_bearing_degrees":45}}, "source_ids":["cp-nasa-shadow-direction","cp-original"] }, { "id":"bcc-cp-10","number":10,"category":"shadows","title":"A longer reach", "lead":"Move the light, keep the pillar: the shadow changes.", "prompt":"The two model pillars are equally tall. Which light angle makes the longer ground shadow?", "assumptions":"Each pillar is vertical and 6 model units tall, on level ground. Angles are measured above the horizon; rays are parallel within each scene.", "kind":"choice", "options":[{"id":"low","label":"A · The lower light at 30°"},{"id":"high","label":"B · The higher light at 60°"},{"id":"same","label":"Both shadows have equal length"}], "answer":{"values":["low"]}, "hint":"Follow a ray past the pillar’s top until it meets the ground.", "retry":"Height is fixed, but the ray reaches the ground at a different distance.", "explanation":"A, the 30° light. A shallower ray travels farther horizontally before reaching the ground. In this ideal geometry, length = height ÷ tan(angle): about 10.4 units at 30°, versus 3.5 at 60°.", "takeaway":"A lower light produces a longer shadow on level ground. Real slopes can change the result.", "figure":{"kind":"shadow-length","file":"figures/10-shadow-length.svg","title":"Two equal pillars with low and high lighting","description":"Scene A has a 6-unit pillar, light at 30 degrees above horizontal, and a ground shadow about 10.4 units long. Scene B has the same 6-unit pillar, light at 60 degrees, and a shadow about 3.5 units long.","model":{"height":6,"angles":[30,60]}}, "source_ids":["cp-nasa-sky","cp-original"] }, { "id":"bcc-cp-11","number":11,"category":"evidence","title":"Look, then interpret", "lead":"An observation of a drawing and a claim about real rock are different things.", "prompt":"Which two statements can you directly observe in this illustration? Select both.", "assumptions":"This original drawing has no scale or field measurements. Its three bands are visual labels, not identified rock formations.", "kind":"multi", "options":[{"id":"opening","label":"The drawing shows one opening through the fin."},{"id":"bands","label":"The drawing has three labeled bands."},{"id":"metres","label":"The opening in a real Bryce fin is 4 m wide."},{"id":"cause","label":"Freezing water definitely made this particular opening."}], "answer":{"values":["opening","bands"]}, "hint":"Could someone check the claim just by looking at the marks on this page?", "retry":"Count what is drawn. A measurement or cause needs evidence beyond the illustration.", "explanation":"One opening and three labeled bands are visible. Neither a real-world width nor the cause of a particular opening follows from this drawing. NPS explains frost wedging as a Bryce process, but a general explanation does not turn an invented fin into a field record.", "takeaway":"Separate what is shown, what is inferred and what has been measured.", "figure":{"kind":"observed-fin","file":"figures/11-observed-fin.svg","title":"An illustrative fin with an opening","description":"An original rock-fin drawing contains one opening and three labeled horizontal bands: upper, middle and lower. No scale bar or measured location is provided.","model":{"openings":1,"bands":["upper","middle","lower"]}}, "source_ids":["cp-nps-hoodoos","cp-original"] }, { "id":"bcc-cp-12","number":12,"category":"evidence","title":"Can this source see it?", "lead":"A detailed-looking model is only as informative as the evidence behind it.", "prompt":"You need measurements of a recess hidden beneath a rock overhang. Which source directly supports that task?", "assumptions":"This is a desk exercise about source choice. The scan described in option B is hypothetical; no real scan is supplied in this pack.", "kind":"choice", "options":[{"id":"aerial","label":"A · An overhead image whose view of the recess is blocked"},{"id":"scan","label":"B · A ground-level scan that samples the recess, with documented scale, coverage and uncertainty"},{"id":"art","label":"C · An artist’s detailed model of what the recess might look like"}], "answer":{"values":["scan"]}, "hint":"Which source actually records the hidden surface, rather than guessing it?", "retry":"Extra visual detail does not substitute for an observation of the surface you need.", "explanation":"B. It records the target surface and documents how to interpret its dimensions. A cannot see the recess; C can illustrate a possibility but is not a measurement. Even a real scan needs a coverage and uncertainty check. No substitute model here establishes a ground scan of Thor’s Hammer.", "takeaway":"Match the evidence to the question. A beautiful reconstruction cannot fill a measurement gap by appearance alone.", "figure":{"kind":"source-choice","file":"figures/12-source-choice.svg","title":"Three ways to represent a hidden recess","description":"Three conceptual panels show an overhead view blocked by an overhang, ground-level rays reaching the recess, and an imagined dotted outline. They are illustrations of source methods, not actual images, point clouds or survey results.","model":{"aerial_visible":false,"ground_visible":true,"artist_measured":false}}, "source_ids":["cp-original"] } ] }