EAR 110 1st Edition Lecture 12Outline of Previous Lecture:I. Types of volcanoesII. How do gases affect magma?III. Viscosity and eruptionsIV. Classification of igneous rocksV. Lava flowsVI. Flood basalts Outline of Current Lecture:I. Volcanic domesII. Monitoring volcanoesIII. Depositional environment and sedimentIV. Making SedimentV. Clast SizesVI. Clast ShapesVII. SortingVIII. Factors affecting size, shape, and sortingIX. Common clastic sedimentary rocksX. Sediment to rock processChapter 6: VolcanoesChapter 7: Sedimentary RocksI. Volcanic domesa. Grow from inside as magma injected into interior of domeb. Grow as magma breaks through surfacec. Destroyed when steep flanks collapse or explosions from build up of gasesd. Rocks: obsidian, breccia, tuffII. Monitoring volcanoesa. Seismic activityb. Changes in topographyc. Changes in temperatured. Increased gas activityIII. Depositional Environment and resulting sedimenta. Mountains – high energy, poorly sorted, angular clastsb. Glaciersc. Sand dunes – rounded, well sortedd. Deltas – rounded, well sortede. Steep stream or riverf. Gentle meandering riverg. Lake – low energy environmenth. Wetlands – low energy environmentThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.i. Beach – rounded, well sortedIV. Making Sedimenta. Physical weatheringi. Frost and mineral welding, fracturing, ice, roots, biologic activityb. Chemical weatheringi. Dissolution, oxidation, biological reactions, hydrolysisV. Clast Sizesa. Boulders >10 inchesb. Cobbles <10 inchesc. Pebbles 2-4inchesd. Sand – coarse, medium, or finee. Silt/clayVI. Clast Shapesa. Angularb. Partially roundedc. Rounded (more rounded = further traveled from source)VII. Sortinga. Poorly sorted – all clast sizesb. Moderately sorted c. Well sorted – uniform clast sizeVIII. Factors that affect size, shape, sortinga. Steepness of slopeb. Agent of transportc. Strength of currentd. High/low energy environmente. Distance from sourceIX. Common clastic sedimentary rocksa. Conglomerate – cobbles in sand matrix, high energyb. Breccia – angular fragments in fine grained matrixc. Sandstone – lithified sand, mostly quartzd. Shale – deposited in low energy environment, dominantly claysX. Sediment to rocka. Compaction of grains or particles into preferred orientationb. Cementationi. Silicas, iron oxides are common