Name: Named for the extensive coal measures of Britain  (esp. north England and Wales, by Conybeare and Phillips (1822), but including a lower carbonate rich interval ("Mountain limestone") and an upper more coal rich interval; early naming reflects importance of coal "Industrial Revolution"

In North America this interval shows similar subdivisions that were named Mississippian  (Winchell) and Pennsylvanian (H..S. Williams) ; these are still used in US but only recognized as subperiods elsewhere

Climate and Sea-Level:  dramatic change from greenhouse to icehouse global conditions;  and very widespread continental glaciation in Gondwanland; most extensive in the Paleozoic during esp. late Carboniferous (Pennsylvanian)  and extending into Permian; dozens of advances and retreats probably correspond to very pronounced sea-level fluctuations

Cooling probably related to reduction in greenhouse gas CO2: 2 reasons:

A) may be associated with slow down in seafloor spreading rates due to continental collision   AND,

B) major burial of organic matter (coal)

"Calcite Oceans" of mid  Paleozoic replaced changed to "Aragonite Oceans" (aragonite mineralization, esp. in algal reefs and mollusks, favored; primary aragonite ooids as oppposed to primary calcite ooids)

Cause:  lowered pCO2 and lowered Mg/Ca ratio in sea water: correlates with Icehouse climates"

Plate Tectonics:  very major continent-continent collision; the biggest tectonic event is suturing of Euramerica (= Laurussia or "Old Red Continent") with large Gondwanaland; most landmasses assembled in Pangeic configuration by the end of Pennsylvanian; Except Asia and parts of China; added in Permian

This collision resulted in unprecedented orogenic activity from cnetral Europe  (Hercynian-Variscan) to Northern Africa  (Hercynian-Mauritanian); eastern Laurentia (Alleghenian); mid-continent (Ouachita), and southwest (Ancestral Rockies)  : compressional tectonis everywhere
MISSISSIPPIAN (SUB-) PERIOD (365-322 Ma)

Name:  For bluffs of crinoid-rich limestone along the Mississippi River from Illinois-Iowa south to Missouri ;

"Age of Crinoids"

Climate: Intermediate, with cooling to first glaciatiion of the great Permo-Carb. Glaciation;  still calcite dominated oceans most of period

Sequence Stratigraphy:  later phases of Sloss’s Kaskaskia Supersequence

In eastern North America begin with  widespread black shale Sunbury-Chattanooga at base; very organic rich, anoxic; U-rich (can be dated directly ~350 Ma); stratification, low circulation, organic matter production;

In eastern Pennsylvania coarse clastics: Pocono Sansatone (Pocono "Mtns."); farther west red Mauch Chunk;

in Maryland  shales, ss, coals Rockwell fm at the Sideling Hill roadcut

Locally, above Cleveland shale is Bedford-Berea sandstone of Ohio-Kentucky; then Sunbury black shale up into Borden-Waverly  sediments;
establishment of "Red Bedford delta" extending into northern Ohio from sources to the NE ; embayment between delta and Cinn Arch;

Borden delta prograded from SE black  shales grade upward into condensed bone bed then turbiditic Borden deposits, then carbonates (Salem, St. Louis, St. Genevieve)

In mid-continent see widespread development of crinoid and blastoid rich limestone;  these are commonly karstified, form Mammoth Caves, etc.
famed "Indiana Limestone" (Salem) ; cream colored, cross bedded, fossil fragments, ooids; Empire State quarries; very widely used dimension stone and facing stone;

Burlington limestone famed mid-Missisisippian unit composed of crinoidal debris highest diversity of crinoids and blastoids; very widespread thick crinoidal blanket

In west see somewhat similar patterns; in Canadian Rockies (Alberta); Devonian-Mississippian Exshaw Black Shale overlain by thick Banff-Rundle Formation;  to south Miss. Limestones form hard crests of many Rocky Mountain flatirons Madison is another crinoidal limestone;
Redwall Ls. Forms prominent cliff in Grand Canyon;

In east, above Mississippian carbonates upward change to more shaly Warsaw, Chester series
Mississippian ends with large Miss-Penn unconformity that Sloss used to distinguish base of Absaroka Supersequence

Tectonics:

In west see aftermath of Antler Orogeny;  flysch basin filling east of Roberts Mountain allochthon; Oquirr clastics in Utah;

In eastern North America; Ettensohn recognizes a fourth and last tectophase of Acadian Orogeny;  deepening of basin (Sunbury)  flysch-molassed in Borden, Red Bedford

Widespread Miss/Lower Carboniferous limestones suggest return to tectonic quiescence; but giving way upward to siliciclastics; new pulse associated with the initiation of Alleghenian Orogeny

In mid-continent see renewed activity around the Anadarko Basin (olod Hadrynian-Anadaro failed rift or aulacogen); uplift of Wichita Mountains to south yoked with pulse of swubsidence in  Anadarko; filled with pile of flysch; coarse turbidites; important petroleum basin; just beginning of more massive Ouachita orogeny

Life History:
Recovery from great Late Devonian extinctons; few reefs; no more tabulate strom reefs; Waulsortian buildups

Abundant solitary and hex packed colonial rugose corals

Fenestrate bryozoans rule; Archimedes with corkscrew axis very common

Spiriferid brachiopods and productids

Crinoids heyday; esspecially large box-like camerates
Blastoids: esp. Pentremites , prolific

Sharks, bony fish
Beginning coal swamps;  amphibians;  first reptiles with amniotic egg
PENNSYLVANIAN (SUB-) PERIOD (322-289 Ma)

Name:  Taken from coal-rich strata (mainly Allegheny Group) in Pennsylvania; soft coalsin western Pittsburgh area; anthracite in eastern tectonized Scranton area;

Sequence Stratigraphy:  Base of Pennsylvanian is very widespread unconformity separates older Kaskaskia Supersequence to from the long drawm out Absaroka Supersequence (Pennsylvanian to Triassic)

Miss.-Penn. Unconformity shows evidence of both eustatic draw down and tectonic (diastrophic) uplift; note angular unconformites around Cicinnati Arch and Ozark areas; these may be forebulges uplifted in response to renewed tectonism at onset of Alleghenian and Ouachita orogenies

Sedimentation in Pennsylvanian (upper Carboniferous) is dominated by cycles; very well defined cyclothems
Different end-member types

Pennsylvania type cyclothems: channel sandstones, non-marine shales, underclays, coals; marine shale and thin limestone, channel sandstones’ may be due to shifting delta lobes

Kansas type  sequence boundary coal, nearshore marine shale; ; transgressive marine limestone (TST); core (offshore) black shale,  (MFS) gray shale; regressive limestone; nearshore sandy shale; coal; nearshore shale

Important finding about cyclothems: can be correlated very widely; coal seams also widespread; suggest more than a local cause; eustatic sea level cycles about 199,00 to 400,000 yeara (Milankovitch eccentricity cycles)

Why so well developed?: glaciers in Gondwanaland

Lots of silciclastics in N Am midcontinent; reflects erosion of many mountain belts;
 
 
 

Appalachian Chain and Alleghenian Orogeny Case Study

Allgnenian Orogeny produced major belts and structures of Appalachians (except for Taconics and Acadian belts in New England:

Appalachians divided into segments; northern, central, southern Appalachians

Northern in maritime area of Canada and eastern New England; in Nova Scotia "sandwich" Meguma terrane (east) part of Africa?; middle belt Avalonia (near Northumberland strait; western NS is Laurentia major Carboniferous coal basins; Joggins in world famous for upright tree stumps with Lagerstatten (tiny reptiles, insects, etc)

New England; Alleghenian structures and metamorphisms superimposed over two older orogenies: Taconic and Acadian; Coal in  Boston-Naragansett, RI area (high grade anthracites in metamorphic rx-Worcester phyllite was thought to be Precambrian until Pennsylvanian plants discovered;

Central Appalachians in NY, Pennsylvnania, Maryland;  see Allegheny Plateau  uplifted tilted; rocks jointed; gentle folds; anticlines and synclines in Valley and Ridge area (rug folded) in central Pennsylvania; blinf thrusts

Southern Appalachians: Virginia to Alabama
Five or six distinct belts from east to west:

a) Outer Slate Belt (including Florida subsurface) is Gondwana terrane;

b) (Charlotte) Carolina slate belt (Apparently related to Avalonian terranes may have some African affinites as well;

c) Piedmont: high grade metamorphic belt (Paleozoic metasediments) abundant Carboniferous granites (magmatic  arc of Alleghenian)

d) Blue Ridge-Smokies: late Proterozoic-Early Cambrian metasediments (typically arkoses) and metabasalts (Catoctin "greenstone"): appear to be rift-related rocks of the Blue Ridge terrane that were torn away and then re-collided) perhaps initially docking in the Ordovician Taconic (early phase); then getting pushed further in Acadian docking (of Slate Belt) and finally pushed over 200 km inboard in Pennsylvanian Alleghenian;

e) Valley and Ridge : thin skinned thrusts (repeated stacked sections of Cambrian to Carboniferous strata (same rocks as in the Allegheny Plateau)
mainly thrusts moved along decollements in top of Shady Dolomite-Rome Shale of Mid Cambrian;  others associated with Devonian black shales ; folds less promient than in Central Appalchians; youngest strata folded in southern Applachians are mid Pennsylvanian; these are non-marine molasse

f) Allegheny Palteau NW of Valley and Ridge divided at Allegheny front; flat to gently tilted ( and soe gently folded) strata of foreland basin; youngest are Permian Dunkard Group in West Virginia and eastern Ohio
 

 Scenario: all of the metamorphism and intrusion of Piedmont due to west-directed subduction that closed Rheic Ocean between northern Gondwana (NW Africa) and Laurentia; collision also pushed Blue Ridge westward over old Laurentian shelf area (with Grenville basement);  thrusting and folding due to compression from southeast

Foreland basin subsides but quickly overfills (no flysch phase in Allehenian foreland sediments); lots of paralic, coal-swamp settings;  eventually raised up and tilted; Cinn arch may be forebulge major Carboniferfous flysch involved in folding and thrusting; reactivated rift basin in Arkansas and Oklahoma

Appalachians cut off by Mississippi Embayment in Alabama, but once continued further west hooked around into Ouachita belt (subdued Ouachita Mtns.)

Ouachitas show north-directed thrusts comparable to Valley and Ridge

Ouachita Orogeny produced by compression from south as a portion of present day Mexico and Central America plus South America collided with SE side of Laurentia

Ancesgtral Rockies further NW may also be a response to this compression but here we see thick skinned block uplifts (Uncompagre; Defiance; and ancestral Front Range plus Oklahoma Mountains; intermontane basins accumualted thick arkosic sediments; e.g. Fountain Arkose of modern Front Range in Bouldder-Denver (Red Rocks) area

Meanwhile in Europe getting Hercynian Orogeny; Similar in Europe; start Carboniferous with deep sea flysch (Culm facies); shallow up to molasse with cyclic "Coal Measures"; see in southern England, Germany; metamorphic cores and granitic batholiths (Dartmoor); Europe-Africa
Overall seeing the effects of same huge cont-cont collision : Pangea built
Pennnsylvanian Life:

Marine: invertebrate faunas similar to Mississippian
 but some specialties

 phylloid algal reefs;

fusulinid large forams; shallow carbonates; important index fossils

sponges, rugose coraks

spiny productid brachiopods typical;

crinoids much less diverse than Miss; simple bowl shapes; many spiny types;
Trilobites a minor group of little import

sharks and other fish predators common;

excellent brackish water faunas preserved in Mazon Creek Lagerstattten (Illinois)

Terrestrial:
  Coal swamp ecosystem:  lycopsids, spheonpsids and seed ferns dominant; beautifully preserved in Mazon  nodules

Large dragon fly-like insects; cockroaches plus other now extinct orders; giant millipede relatives

Labyrinthodont  amphibians common and large

Reptiles beginning to diversify
 

No major extinctions in Pennsylvanian; most major groups carry through into Permkian; bt some changes