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GY 112L: Earth History Lab UNIVERSITY OF SOUTH ALABAMA GY 112L: Earth History Lab Week 9: Paleozoic Part 3 Instructor: Dr. Douglas W. Haywick Today’s Agenda The Paleozoic Part 3 (Week 9 exercises) 1) Brachiopods 2) Molluscs 3) Alabama Stratigraphy Brachiopoda Brachiopod Facts: Taxonomy: (under review) Phylum: Brachiopoda Class: Inarticulata Class: Articulata Brachiopoda Brachiopod Facts: Taxonomy: Phylum: Brachiopoda Class: Inarticulata Class: Articulata Range: Cambrian-Recent (Inarticulates were first) Brachiopoda Brachiopod Facts: Taxonomy: Phylum: Brachiopoda Class: Inarticulata Class: Articulata Range: Cambrian-Recent Mode of Life: Marine, benthic, filter feeder Brachiopoda Brachiopod Facts: Taxonomy: Phylum: Brachiopoda Class: Inarticulata Class: Articulata Range: Cambrian-Recent Mode of Life: Marine, benthic, filter feeder Mineral composition: calcite, phosphate Brachiopoda Brachiopod Facts: Taxonomy: Phylum: Brachiopoda Class: Inarticulata Class: Articulata Range: Cambrian-Recent Mode of Life: Marine, benthic, filter feeder Mineral composition: calcite, phosphate Fossil Pres.: pristine (sometimes external molds) The Brachiopod Animal Inarticulates The Brachiopod Animal Inarticulates Brachiopod Symmetry Symmetrical across the valves (down the medial line) Brachiopod Symmetry Symmetrical across the valves (down the medial line) Brachiopod Symmetry Symmetrical across the valves (down the medial line) Articulate Brachiopods Brachiopod Symmetry Symmetrical across the valves (down the medial line) Articulate Brachiopods Brachiopod Symmetry Not symmetrical between the valves Brachiopod Symmetry Not symmetrical between the valves Yes No Mollusca (Mollusks) Mollusk Facts: Taxonomy: Phylum: Mollusca Mollusca (Mollusks) Mollusk Facts: Taxonomy: Phylum: Mollusca Class: Amphineura Bivalvia Gastropoda Cephalopoda Order: Nautiloidea Ammonoidea Belemnoidea Mollusca (Mollusks) Mollusk Facts: Taxonomy: Phylum: Mollusca Class: Amphineura Bivalvia Gastropoda Cephalopoda Order: Nautiloidea Ammonoidea Belemnoidea Range: Gastropoda (Cambrian-Recent) Bivalvia (Cambrian-Recent) Cephalopoda (Cambrian-Recent) Mollusca (Mollusks) Mollusk Facts: Taxonomy: Phylum: Mollusca Class: Bivalvia Gastropoda Range: Gastropoda (Cambrian-Recent) Bivalvia (Cambrian-Recent) Mode of Life: Marine, non-marine, terrestrial, filter feeder, scavenger, predators Mollusca (Mollusks) Mollusk Facts: Taxonomy: Phylum: Mollusca Class: Bivalvia Gastropoda Range: Gastropoda (Cambrian-Recent) Bivalvia (Cambrian-Recent) Mode of Life: Marine, non-marine, terrestrial, filter feeder, scavenger, predators Mollusca (Mollusks) Mollusk Facts: Taxonomy: Phylum: Mollusca Class: Bivalvia Gastropoda Range: Gastropoda (Cambrian-Recent) Bivalvia (Cambrian-Recent) Mode of Life: Marine, non-marine, terrestrial, filter feeder, scavenger, predators Mineral composition: calcite, aragonite Mollusca (Mollusks) Mollusk Facts: Taxonomy: Phylum: Mollusca Class: Bivalvia Gastropoda Range: Gastropoda (Cambrian-Recent) Bivalvia (Cambrian-Recent) Mode of Life: Marine, non-marine, terrestrial, filter feeder, scavenger, predators Mineral composition: calcite, aragonite Fossil Pres.: pristine. molds, casts, chalky The Mollusk Animal Bivalves The Mollusk Animal Gastropods Bivalve Symmetry Symmetrical between the valves Bivalve Symmetry Symmetrical between the valves Not across the valves Bivalve vs Brachiopod Symmetry Bivalve: Symmetrical between Brachiopod: Symmetrical the valves across the valves Bivalve Symmetry Beware Scallops and Oysters scallops look symmetrical across the valve oysters are not symmetrical at all but they are not Alabama Stratigraphy and Rock Suites Collections of Paleozoic rocks from our fair state Alabama Stratigraphy and Rock Suites Paleozoic rocks Alabama Stratigraphy and Rock Suites Paleozoic rocks Bonus Question: Color Paleozoic rock outcrop areas Alabama Stratigraphy and Rock Suites Rocks this week: a collection of specimens from northern Alabama (including Red Mountain) which is hematite (iron ore). Lab Time GY 112L: Earth History Lab Week 9: Paleozoic Part 3 Instructor: Dr. Doug Haywick [email protected] This is a free open access lecture, but not for commercial purposes. For personal use only. .
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