Impact Tectonics vers. 082011.kmz

Impact Tectonics vers. 08/2011
Impecttonics.org, August 27, 2011
Hurricane Irene

Far-field strains from known, large impacts
Chesapeake(~35 Ma) overprinting
Chicxulub(~65 Ma)

Crustal lineaments

Untitled Path

Crustal seismogenic zones
N20o-N50o and W65o-W105o. Determined using 3954 earthquake records for the period 1973-2005 from the National Earthquake Information Center. Zones represent densities of .001 to .003 earthquakes per sq km calculated using ArcView Spatial Analyst, with a cell size of 0.1 degree and a search radius of 50km. Earthquakes magnitude ranges from 0.9 to 7.3.

Charlevoix, QC

Hidalgo, MX

Clayborn - Little Rock, AK

Garvin, OK

New Madrid, MO-TN

Knoxville-Athens, TN

Charleston, SC

Hays, Ka

Amarillo, Tx

Trinidad-Raton, Co-NM

Marathon, TX

Lancaster-Reading

Ramapo

New Hampshire

Kiamick-Harrington, QC

New Brunswick

Adirondack

Ashtabula

Ocean lineaments
Central America, West-Central Atlantic, and Eastern Pacific
Polyline
ENTITY = Polyline
LAYER = MID_ATL_LINEAMENTS
ELEVATION = 0
THICKNESS = 0
COLOR = 1
COLOR = 0

Chesapeake Impact, Virgina, U.S.A. )

Far-field strain rings

Crater, ~90 km.
Chesapeake Bay
Path
ID = 2

Chesapeake Invader
Click me

Chicxulub Impact, Yucatan, Mexico

Crater, ~170 km
Chicxulub

Chicxulub
Click me

Path

2008 Horizontal vectors of crustal-plate motion
NASA/JPL GPS 06092008
Vectors magnitude weighted x.1 degree
AGMT
ALAM
APEX
ID = 5
STATION = APEX
TYPE = POS
LATE = 0.13
LONE = 0.21
HE = 0.51
TYPE_2 = VEL
XVEL = -15.79
YVEL = -9.68
ZVEL = 1.26
XERR = 0.09
YERR = 0.06
ZERR = 0.23
TYPE_3 = VEL
MAG = 19
BRG = 238
BCWR
BEPK
CASA
CICE
ID = 48
STATION = CICE
HEIGHT = 87640
LATE = 0.22
LONE = 0.23
HE = 0.94
XVEL = -39.47
YVEL = 17.02
ZVEL = -3.45
XERR = 0.14
YERR = 0.07
ZERR = 0.33
MAG = 45
BRG = 293
CORX
COSO
CTMS
STATION = CTMS
LATE = 0.05
LONE = 0.05
HE = 0.19
XVEL = -16.37
YVEL = 2.58
ZVEL = 2.81
XERR = 0.02
YERR = 0.02
ZERR = 0.08
MAG = 16
BRG = 279
DYER
ECHO
FERN
GLRS
GMPK
STATION = GMPK
YVEL = -6.62
ZVEL = 5.5
GNPS
GOLD
GUAX
HNPS
HOGS
STATION = HOGS
YVEL = 5.68
IMPS
IVCO
MERC
PERL
RAIL
REPO
SHOS
STATION = SHOS
YVEL = -9
SMYC
TIVA
AJAC
STATION = AJAC
XVEL = 20.99
ALBH
ALGO
STATION = ALGO
ALIC
STATION = ALIC
XVEL = 31.56
AMMN
ANKR
STATION = ANKR
ANTC
STATION = ANTC
XVEL = 7.99
ANTO
AOML
STATION = AOML
HEIGHT = 102.3
ZVEL = -0.41
AREQ
ARTU
STATION = ARTU
ASHV
STATION = ASHV
ZVEL = -1.02
AUCK
STATION = AUCK
AZCN
BAHR
STATION = BAHR
BAKO
STATION = BAKO
YVEL = -7.04
STATION = BAN2
YVEL = 34
BARB
STATION = BARB
BARH
STATION = BARH
BILI
STATION = BILI
BJFS
BLYN
BOGI
STATION = BOGI
BOGT
STATION = BOGT
STATION = BOR1
BRAZ
BREW
STATION = BREW
YVEL = -10
BRMU
BRST
STATION = BRST
BRUS
STATION = BRUS
BUCU
STATION = BUCU
BURN
BZRG
STATION = BZRG
XVEL = 19
CABL
STATION = CABL
CAGL
STATION = CAGL
CAGS
STATION = CAGS
CAGZ
STATION = CAGZ
CANB
STATION = CANB
CAST
CEDA
CEDU
STATION = CEDU
CENA
STATION = CENA
CFAG
STATION = CFAG
CHUM
STATION = CHUM
CHUR
CHWK
CHZZ
STATION = CHZZ
XERR = 1
CMBB
CNDR
CNWM
STATION = CNWM
COAT
COCO
STATION = COCO
COLA
STATION = COLA
CONZ
STATION = CONZ
COON
STATION = COON
COPO
STATION = COPO
CORC
CORD
STATION = CORD
CORV
STATION = CORV
COSA
CPXF
DAEJ
DARR
DARW
STATION = DARW
STATION = DAV1
HEIGHT = 44420
DAVR
STATION = DAVR
DDSN
DGAR
STATION = DGAR
DLFT
STATION = DLFT
DNRC
STATION = DNRC
DQUA
DRAG
STATION = DRAG
DREJ
STATION = DREJ
DUBO
STATION = DUBO
DUBR
STATION = DUBR
DUCK
EBRE
STATION = EBRE
EGAN
EISL
STATION = EISL
ELKO
EPRT
ERLA
ESTI
STATION = ESTI
LONE = 1
FAIR
FBYN
STATION = FBYN
YVEL = -3
FFMJ
STATION = FFMJ
FLIN
STATION = FLIN
FOOT
FORT
GALA
STATION = GALA
GALB
GARL
GDAC
GENO
STATION = GENO
YVEL = 15
GGAO
GLPT
GLSV
STATION = GLSV
YVEL = 12
GMAS
STATION = GMAS
GNAA
STATION = GNAA
GOBS
GOPE
STATION = GOPE
XVEL = 20
GOSH
GOUG
GRAS
STATION = GRAS
GRAZ
STATION = GRAZ
GUAM
STATION = GUAM
GUAO
STATION = GUAO
GUAT
STATION = GUAT
GWEN
HARB
STATION = HARB
HARK
STATION = HARK
HART
HBRK
HEBE
HELJ
STATION = HELJ
HERS
STATION = HERS
XVEL = 16
HFLK
STATION = HFLK
HILO
HKLO
STATION = HKLO
HNLC
STATION = HNLC
HEIGHT = 21969
HNPT
STATION = HOB2
HOBA
STATION = HOBA
HOFN
STATION = HOFN
HOLB
HOLM
STATION = HOLM
HEIGHT = 419.3
HOPB
STATION = HOPB
HOUS
STATION = HOUS
ZERR = 1
HRAO
HUEG
STATION = HUEG
HVLK
STATION = HVLK
IISC
STATION = IISC
INEG
INVK
IRKJ
STATION = IRKJ
IRKT
STATION = IRKT
ISTA
STATION = ISTA
JAMA
STATION = JAMA
JNPR
JOZE
STATION = JOZE
JTNT
STATION = JTNT
KARR
STATION = KARR
KELS
KELY
STATION = KELY
KERG
STATION = KERG
STATION = KGN0
KGNI
STATION = KGNI
KHAJ
KIRU
STATION = KIRU
STATION = KIT3
KODK
KOKB
KOSG
STATION = KOSG
KOUC
STATION = KOUC
KOUR
STATION = KOUR
KSMV
STATION = KSMV
KSTU
STATION = KSTU
KUNM
LAMA
STATION = LAMA
LEWI
LEXI
STATION = LEXI
LHAS
STATION = LHAS
LHUE
LIND
LKCP
STATION = LKCP
LKHU
LMNO
STATION = LMNO
LPGS
LTHM
STATION = LTHM
LUBB
STATION = LUBB
STATION = MAD2
MADR
STATION = MADR
STATION = MAG0
MALD
MALI
STATION = MALI
MANA
STATION = MANA
MANZ
STATION = MAS1
MASP
STATION = MASP
MATE
STATION = MATE
MAUI
MBAR
MBWW
MCMU
STATION = MCMU
HEIGHT = -1106
MDMT
MDVO
STATION = MDVO
MEDI
STATION = MEDI
METS
STATION = METS
MIKL
STATION = MIKL
MINE
MINS
MIZU
STATION = MIZU
MKEA
MOBN
STATION = MOBN
MOIN
STATION = MOIN
MORP
STATION = MORP
MSKU
STATION = MSKU
MTCX
MTKA
STATION = MTKA
NAIN
NALL
STATION = NALL
NANO
STATION = NANO
NDAP
NDBC
NDSK
NEAH
STATION = NEAH
NEWP
STATION = NEWP
NJIT
NKLG
STATION = NKLG
NLIB
NNOR
STATION = NNOR
ZERR = 2
STATION = NOT1
NOTO
STATION = NOTO
NOUM
STATION = NOUM
NPLD
STATION = NPLD
NRIL
STATION = NRIL
NSSP
NSSS
NTUS
STATION = NTUS
NVSK
STATION = NVSK
STATION = NYA1
OBER
STATION = OBER
HE = 3
STATION = ODS5
ZVEL = -4
OHIG
STATION = OHIG
ONSA
STATION = ONSA
OPBL
OPCL
OSJE
STATION = OSJE
PADO
STATION = PADO
PAMA
STATION = PAMA
PARC
STATION = PARC
PASO
PATT
PDEL
STATION = PDEL
PENC
STATION = PENC
PENT
PERT
STATION = PERT
PETP
STATION = PETP
PIMO
STATION = PIMO
PLTC
POLV
STATION = POLV
POTM
STATION = POTM
POTS
STATION = POTS
PRCO
STATION = PRCO
PRDS
PTBB
STATION = PTBB
PTSG
PUPU
STATION = PUR3
QUIN
RABT
STATION = RABT
RAMO
STATION = RAMO
RBAY
STATION = RBAY
RBUT
REDM
STATION = REDM
RESO
REYK
REYZ
RIOG
STATION = RIOG
RIOP
STATION = RIOP
RUBY
RWDN
STATION = RWDN
SACH
SANT
STATION = SANT
SEAT
STATION = SEAT
SEAW
STATION = SEAW
SEDR
SELE
STATION = SELE
SFER
STATION = SFER
SHIN
SHLD
SIMO
STATION = SIMO
SLID
SLOR
STATION = SLOR
SMEL
SOFI
STATION = SPT0
SSIA
STATION = SSIA
STATION = STB1
STJO
STATION = STJO
STATION = STR2
STRL
SULP
STATION = SULP
SUTH
SUTM
SUWN
SYOG
STATION = SYOG
TAEJ
STATION = TAEJ
TAHI
TAIS
TCMS
TCUN
TEGU
STATION = TEGU
STATION = TID1
STATION = TID2
TITZ
STATION = TITZ
TIXI
STATION = TIXI
TLKA
STATION = TLKA
TLSE
STATION = TLSE
TMGO
TNML
TRAB
STATION = TRAB
TRND
STATION = TRND
STATION = TRO1
TROM
STATION = TROM
TSEA
TSKB
STATION = TSKB
TUBI
STATION = TUBI
TUNG
TWHL
TWTF
UCLU
STATION = UCLU
ULAB
STATION = ULAB
UNSA
STATION = UNSA
UPAD
STATION = UPAD
UPSA
URUM
STATION = URUM
USNA
USNO
USUD
STATION = USUD
UZHL
STATION = UZHL
VCAP
STATION = VCAP
VCIO
STATION = VCIO
VENE
STATION = VENE
VESL
STATION = VESL
VILL
STATION = VILL
ZVEL = -1
VIMS
WETB
STATION = WETB
WHIT
WILL
WLCI
WLPS
STATION = WLPS
WROC
STATION = WROC
WSLR
WSMN
WSRT
STATION = WSRT
WTZA
STATION = WTZA
WTZJ
STATION = WTZJ
WTZR
STATION = WTZR
WTZT
STATION = WTZT
WTZZ
STATION = WTZZ
WUHN
STATION = WUHN
XIAN
STATION = XIAN
YAKA
YAKT
STATION = YAKT
YAKZ
STATION = YAKZ
STATION = YAR1
ZVEL = 1
STATION = YAR2
YARR
STATION = YARR
YBHB
YEBE
STATION = YEBE
YELL
YSSK
ZAMB
STATION = ZAMB
ZECK
STATION = ZECK
ZIMJ
STATION = ZIMJ
ZIMM
STATION = ZIMM
ZWEN
STATION = ZWEN

Ocean isochrons
From A Global Isochron Chart by J.-Y. Royer, R.D. Müller, L.M. Gahagan, L.A. Lawver, C.L. Mayes, D. Nürnberg and J.G. Sclater, University of Texas Institute for Geophysics Technical Report No. 117, 1992 http://ftp.agg.nrcan.gc.ca/app/utig_report_e.html#intro.

921 32 ISOCHRON 31 NORTH AMERICA/AFRICA

921 33 ISOCHRON 31 GREENLAND/NORTH AMERICA

921 34 ISOCHRON 31 ROCKALL/NORTH AMERICA

921 35 ISOCHRON 31 PORCUPINE/NORTH AMERICA

921 36 ISOCHRON 31 IBERIA/NORTH AMERICA

921 62 ISOCHRON 31 GREENLAND/NORTH AMERICA

921 69 ISOCHRON 31 SOUTH AMERICA/AFRICA

9488 83 ISOCHRON A 31 201/701 SOUTH ATLANTIC SAM

9488 84 ISOCHRON A 31 201-802 SOUTH AMERICAN ANT

921 110 ISOCHRON 31 IBERIA/NORTH AMERICA

921 120 ISOCHRON 31 PORCUPINE/NORTH AMERICA

921 136 ISOCHRON 31 ROCKALL/NORTH AMERICA

9488 144 ISOCHRON A 31 705-501 NORTH OF MASCARENE

9488 145 ISOCHRON A 31 701-501 ARABIAN SEA & EAST

9488 156 ISOCHRON A 31 511-802 SOUTHEAST INDIAN R

9488 157 ISOCHRON A 31 511-801 WHARTON BASIN AUS/

9488 188 ISOCHRON A 31 201/701 SOUTH ATLANTIC SAM

9488 189 ISOCHRON A 31 701-705 MASCARENE BASIN SE

9488 190 ISOCHRON A 31 705-501 NORTH OF MASCARENE

9488 192 ISOCHRON A 31 701-705 MASCARENE BASIN SE

9488 193 ISOCHRON A 31 701-705 MASCARENE BASIN SE

9488 196 ISOCHRON A 31 701-501 ARABIAN SEA & EAST

9488 198 ISOCHRON A 31 - 802-701 SOUTHWEST INDIAN

921 242 ISOCHRON 31 NORTH AMERICA/AFRICA

921 243 ISOCHRON 31 SOUTH AMERICA/AFRICA

9488 252 ISOCHRON A 31 750/802 AGULHAS BASIN MALV

9488 270 ISOCHRON A 31 511-801 WHARTON BASIN AUS/

9488 271 ISOCHRON A 31 802-801 AUSTRALIAN-ANTARCT

931 274 ISOCHRON 31 LORD HOWE RISE/AUSTRALIA

9488 297 ISOCHRON A 31 201-802 SOUTH AMERICAN ANT

9488 298 ISOCHRON A 31 - 802-701 SOUTHWEST INDIAN

9488 299 ISOCHRON A 31 511-802 SOUTHEAST INDIAN R

9488 300 ISOCHRON A 31 750/802 AGULHAS BASIN MALV

9488 301 ISOCHRON A 31 802-801 AUSTRALIAN-ANTARCT

931 330 ISOCHRON 31 PACIFIC/MARIE BYRD LAND

931 333 ISOCHRON 31 PACIFIC/BELLINGHAUSEN

931 336 ISOCHRON 31 LORD HOWE RISE/AUSTRALIA

931 357 ISOCHRON 31 PACICFIC/FARALLON

931 358 ISOCHRON 31 PACIFIC/BELLINGHAUSEN

931 359 ISOCHRON 31 PACIFIC/MARIE BYRD LAND

9788 363 ISOCHRON 31, PACIFIC/KULA

921 37 ISOCHRON 34 NORTH AMERICA/PORCUPINE

921 38 ISOCHRON 34 NORTH AMERICA/ROCKALL

921 39 ISOCHRON 34 NORTH AMERICA/IBERIA

921 40 ISOCHRON 34 NORTH AMERICA/AFRICA

921 70 ISOCHRON 34 SOUTH AMERICA/AFRICA

9488 85 ISOCHRON A 34 - 201-701 SOUTH ATLANTIC

9488 86 ISOCHRON A 34 201-802 WEDDELL SEA SAM/

921 111 ISOCHRON 34 NORTH AMERICA/IBERIA

911 113 EXTINCT RIDGE IN BAY OF BISCAY, Mueller

921 121 ISOCHRON 34 NORTH AMERICA/PORCUPINE

911 122 EXTINCT RIDGE IN BAY OF BISCAY, Mueller

921 137 ISOCHRON 34 NORTH AMERICA/ROCKALL

9488 146 ISOCHRON A 34 701-501 MASCARENE BASIN

9488 147 ISOCHRON A 34 501-802 SOUTHEAST INDIAN

9488 148 ISOCHRON A 34 501-802 SOUTHEAST INDIAN

9488 158 ISOCHRON A 34 511-831W WEST OF KERGUEL

9488 159 ISOCHRON A 34 511-831W WEST OF KERGUEL

9488 160 ISOCHRON A 34 511-801 WHARTON BASIN AU

9488 161 ISOCHRON A 34 511-801 WHARTON BASIN AU

9488 162 ISOCHRON A 34 511-801 WHARTON BASIN AU

9488 194 ISOCHRON A 34 701-705 MASCARENE BASIN

9488 199 ISOCHRON A 34 701-501 MASCARENE BASIN

9488 203 ISOCHRON A 34 - 201-701 SOUTH ATLANTIC

9488 204 ISOCHRON A 34 750-701 AGULHAS BASIN MA

9488 205 ISOCHRON A 34 802-701 SOUTHWEST INDIA

9488 206 ISOCHRON A 34 802-701 SOUTHWEST INDIA

9488 207 ISOCHRON A 34 802-701 SOUTHWEST INDIA

9488 211 ISOCHRON A 34 752-201 Malvinas jump, A

9488 253 ISOCHRON A 34 750-701 AGULHAS BASIN MA

9488 255 ISOCHRON A 34 802-750 AGULHAS BASIN MA

9455 273 ISOCHRON A 34 802-801 AUSTRALIAN-ANTAR

9488 303 ISOCHRON A 34 201-802 WEDDELL SEA SAM/

9488 305 ISOCHRON A 34 501-802 SOUTHEAST INDIAN

9488 306 ISOCHRON A 34 831-802W SOUTHWEST OF KE

9455 307 ISOCHRON A 34 802-801 AUSTRALIAN-ANTAR

931 331 ISOCHRON 34 PACIFIC/MARIE BYRD LAND

9488 334 ISOCHRON A 34 511-831W WEST OF KERGUEL

9488 335 ISOCHRON A 34 831-802W SOUTHWEST OF KE

931 360 ISOCHRON 34 PACIFIC/FARALLON

931 361 ISOCHRON 34 PACIFIC/BELLINGSHAUSEN

921 42 ISOCHRON 0 IBERIA/NORTH AMERICA

9488 87 ISOCHRON M0 201-701 SOUTH ATALANTIC SAM

9488 90 ISOCHRON M0 292-751 SOUTH ATALANTIC SAM

9488 208 ISOCHRON M0 701-802 MOZAMBIQUE AND ASTR

9488 209 ISOCHRON M0 701-702 SOMALI BASIN AFR/MA

9488 210 ISOCHRON M0 201-701 SOUTH ATALANTIC SAM

9488 212 ISOCHRON M0 752-201 Malvinas jump, SOUT

9488 223 ISOCHRON M0 701-702 SOMALI BASIN AFR/MA

9488 308 ISOCHRON M0 201-802 WEDDELL SEA SAM/ANT

9488 309 ISOCHRON M0 701-802 MOZAMBIQUE AND ASTR

991 376 Isochron M-0 Hawaiian lineations

9788 370 ISOCHRON M29, Izanagi Lin.

9788 375 ISOCHRON M29, Phoenix Lin., Larson

9788 382 ISOCHRON M29, Hawaiian Lin.

Suspected, large impacts
Far-field tectonic strains from 6 large impact events

South Georgia, Southwest Atlantic
Est. Mid-Miocene age (~15 Ma. ?) 2 impact craters, Est 360 km and 60 km. diameter Exposed submarine. The term Middle Miocene disruption, alternatively the Middle Miocene extinction or Middle Miocene extinction peak, refers to a wave of extinctions of terrestrial and aquatic life forms that occurred around the middle of the Miocene Epoch, c. 14.8 to 14.5 million years ago, during the Langhian stage of the Miocene (http://en.wikipedia.org/wiki/Middle_Miocene_disruption) .
Sedimentation in the subantarctic region was relatively continuous during the Late Cretaceous to earliest Miocene, and hiatuses represent short stratigraphic intervals. At six of the seven ODP SItes for Leg 114, major hiatuses separate overlying middle to upper Neogene sediments from the middle Paleogene to lowermost Neogene. Since —18.5 Ma, all of the Leg 114 sites, except Site 704, were subjected to numerous erosional and nondepositional episodes. Physical-properties measurements suggest a removal of hundreds of meters of sediment at some hiatuses.

Annotation

Rio Grande Rise

Weddell Sea abyssal plains

Argentine abyssal plains

South Georgia

South Georgia 2

Craters, exposed submarine
South Georgia 1, ~300 km diameter
South Georgia 2, ~60 km

Far-field strain rings
South Georgia 1, 660km
South Georgia 1, 1700 km
South Georgia 1, 2900 km
South Georgia 2, 660 km

Faults mapped on sesimic-reflection profiles

DSDP-ODP Annotated

One hole was drilled to a maximum penetration of 842 meters. Two major lithologic units occur at this site. Unit 1 consists of siliceous mud and mudstone of Pleistocene to mid-Eocene age. Unit 2 consists of terrigenous mudstone and marly chalk of middle Eocene to Late Cretaceous age. Data strongly suggest that sediment accumulation was rapid during the late Oligocene and the early Miocene. Part of Unit 1 The presence or absence of mid-Miocene sediments cannot be established beyond doubt.
A Middle Miocene part of Unit 1 contains occasional indistinct areas or disturbed layers where the volcanic glass content is greater than average (up to 20%) and where the silt content is 40%. Below this, clay makes up about 50% to 60% of this section with quartz, volcanic glass, feldspar, manganese oxides, and zeolites occur in trace amounts to 5%. http://www.deepseadrilling.org/39/volume/dsdp39_07.pdf

Below a surficial layer of Quaternary diatom ooze, Hole 700B exhibits a pelagic carbonate record extending from the middle
Eocene down to the Coniacian(?) and Campanian, at which depth the hole was discontinued because the drill bit was lost.
The sediments consist primarily of pelagic carbonates showing a progressive lithification with depth, from soft ooze to friable
chalk, indurated chalk, and finally, to limestone.

Early Miocene-Quarternary siliceous and clayey oozes overlie a lower Miocene-upper middle Miocene hiatus, with underlying diatom, siliceous, and nonnofossil chalk ranging in age from Ealry Miocene to late Paleocene.

A thin, upper gravel lag deposit composed of chert pieces and dropstones (sandstone, gneiss), as well as one manganese nodule o0verlies an extensive unconformit, with underlying Middle (?) to Early Eocene - Late Cretaceous ooz over altered basalt. Faulting along the western perimeter of Northeast Georgia Rise is tentatively assigned a late Miocene age and is likely to be related to interaction with the advance of the South Georgia block in response to seafloor spreading in the Scotia Sea. This deformational event may be responsible for the post-eruptive veining and mineralization of the basalt in Subunit HIB.

Four unconformities are recognized at Site 512. The first separates Pleistocene and Pliocene sediments, the second is within the Pliocene, the third separates Pliocene from upper Miocene, and the fourth, middle Miocene from middle Eocene sediments. The unconformities are likely to be related to periodic intensification of the Circumpolar Deep Water of the Antarctic Circumpolar Current which eroded and/or prevented deposition on the Maurice Ewing Bank. Because of the duration of these unconformities, it is impossible to establish whether each can be associated with one or several paleoceanographic events.
http://www.deepseadrilling.org/71/volume/dsdp71pt1_03.pdf

A major change in the conditions at Site 328 occurred at the close of the Eocene. The sedimentation rate dropped substantially to about 1.8 m/m.y. during the Oligocene (Figure 7), and there was a significant increase in the quantity of siliceous organisms in the sediments accompanied by a spectacular decrease in clay content (lower part of Unit 2). Major breaks occur in the stratigraphic record at the site from the late Eocene to the late early Oligocene (approximately 5 m.y.) and from the latest Oligocene to the middle Miocene (approximately 10 m.y.). There is a slight decrease in the sedimentation rate to 1.6 m/m.y. during the middle and late Miocene (upper part of Unit 2) with evidence of winnowing and increase in the quantity of manganese nodules and coarse clastic detritus during this time interval. Hence an increase in the bottom current velocity is indicated beginning probably in the late Eocene and continuing through the Miocene. Cold-water microfossils become dominant in the middle Miocene, and although there is no certain ice-rafted material below the uppermost Miocene (5-7 m.y.), the sand-sized fraction could represent glacially derived material at least in part.

Lineaments

Paths
South Georgia 2

South Georgia 1

Seismic reflection profile line 7
Line 1
Line 2
Line 3

Norfolk Basin, Southwest Pacific
Est. End Eocene age (~ 34 Ma. ?)
~200 km diameter, exposed but submerged

Norfolk Basin
Click me

Crater ~360 km diameter

Canada basin, Arctic
Est. Paleocene-Eocene age
(~57 Ma.?), ~180 km diameter

Canada Basin

Crater

North Shore

Arctic path1

Arctic path2

Arctic path 3

Arctic path4

Mid-Pacific Mts.
Est. Mid-Cretaceous age
(~93.5-100 Ma est.) Multiple craters, exposed submarine

Hawaiian-Emperor Seamounts

Big Island

Midway Islands

Suiko Seamount

Detroit Tablemount

Hancock Seamount

Colahan Seamount

Abbot Seamont

Mid-Pacific Mts.
http://www.deepseadrilling.org/62/volume/dsdp62_02.pdf
The litho- and biostratigraphic framework obtained from the sediment column penetrated at Site 463 allows us to describe the evolution of the depositional environment
in the wesern Mid-Pacific Mountains. At present, the age of the Mid-Pacific Mountains is not well known (Larson, 1976). However, the oldest sediments at Site 463 are of Barremian age, approximately 20 m.y. older than those overlying basaltic rocks at Site 171 (Winterer, Ewing, et al., 1973), and approximately 40 m.y. older than those overlying the volcanic basement at Site 313 (Larson, Moberly, et al., 1975). It is clear, therefore, that the structural high of the western Mid-Pacific Mountains is considerably older than previously believed. Comparison with the results obtained at the other sites, where basement rocks have been reached after penetrating the entire sediment column (Fig. 1), makes it clear that the Mid-Pacific Mountains represent a complex structural high whose segments have been built or added to by volcanic events stretching over the extraordinarily long time of at least 40 m.y.

Manahiki Plateau

Shasky Rise

Hawaiian Islands

Marshall Islands

Craters, with diameter

DSDP Leg 17 Site 166
Volcanogenic sediments overlie Fe- and Mn-charged marly mudstones which rest on pillowed and nonpillowed ocean ridge basalts that probably represent the top of crustal Layer 2 formed at the crest of the East Pacific Rise.
Albian-Cenomanian (~100 Ma) nannofossil marl mudstone, interbedded with zeolitic altered ash and pieces of brown chert with drusy quartz overlie gray, dense, non-vesicular basalt (115-120 Ma).
Core 18 contains no identifiable nannofossils, and Core 19 contains only a few, very poorly preserved Radiolaria that are probably Cretaceous in age. Radiolaria are absent in Core 20 except for a few down-mixed specimens; however, several broken specimens of foraminifera suggest a Cenomanian or Albian age for this core. Thus, any lower Eocene and Paleocene that exists would be contained in the interval sampled by Core 18. Core 19 may represent the only Upper Cretaceous recovered at this site. Only radiolarians are found in Cores 21 to 25. The calcareous microfossils of Cores 26 to 28 indicate the basement age is late Hauterivian to early Aptian. However, the radiolarian assemblage in Cores 23 to 28 is comparable to that identified as late Albian to Cenomanian in age at other sites of this leg. This discrepancy in age might be accounted for by the down-mixing of a younger radiolarian fauna into the older calcareous sediments of Cores 26 to 28 during the drilling process. The fact that Core 22 contains a very well preserved radiolarian assemblage that is almost totally different from the underlying cores does not support his argument. There remains the explanation that the calcareous microfossils of Cores 26 to 28 are reworked during deposition from a nearby outcrop of older sediments. But if the radiolarians give the true basement age as no older than Late Albian, whence came the Hauterivian calcareous nannoplankton? The basalt "basement" sampled at this site might represent a widespread extrusion or flood of basalt which considerably postdates crustal formation. If this is true, the Late Albian age given by the radiolarians would be a minimum date for this event. The reworked Hauterivian nannofossils could have been preserved from the basalt flood on an isolated topographic high (such as the Magellan Rise). Thus, they provide an estimate of the minimum age of the actual crust

DSDP Leg 17 Site 167
Magellan Rise: L. Tithonian - E. Berriasian (~145 Ma) limestone over altered, brecciated basalt
Albian limestone in Cores 62 and 63 contain evidence for more massive displacements of sediment in the form of (a) a pebbly mudstone containing large clasts in a homogeneous matrix; (b) large-scale slumping; and (c) brecciated chert and brecciated limestone. The brecciated limestone shows large angular clasts that apparently have not been transported over long distances. The brecciated chert is cemented by well-crystallized sparry calcite and quartz. This fragmentation obviously occurred when the chert was already hard. Furthermore, the absence of any sediment filling between the fragments suggests that the chert was probably broken when the sediments were already partially lithified.
A carbonate plus chert section with little volcanic admixture overlies a section of flows and possible sills which are cut by tectonic breccia zones. Trace element chemistry suggests ocean ridge tholeiites, but the intense alteration and possible loss of trace elements leave open the possibility that the rocks are ocean island tholeiites or mildly alkaline basalts erupted during the volcanic construction of Magellan Rise, a broad volcanic edifice which evidently failed to reach sea level. An older sediment section may exist at depth beneath this edifice. The breccia zones served as conduits for hydrothermal solutions during the volcanic activity.

DSDP Leg 17 Site 169
Site 169: Early Cenomanian (~99 Ma) zeolitic claystone over basalt
The upper sediments are brown clays with porcellanitic chert beds. Cenomanian or Turonian beds in the lower part of these clays are intruded by a deuterically altered, but otherwise fairly fresh diabase sill. Still lowerthere are, in turn, chalk free of volcanic components, brown zeolitic clay, and the basement (Layer 2) composed of pillowed ocean ridge basalt. Both flows and sill are very low in trace elements, but in many other ways the sill appears to be alkaline. This problem is unresolved. If the sill is an ocean ridge basalt, it is unrelated to any currently known spreading center [The basement rocks are chemically so different from those currently erupted at the crest of the East Pacific Rise that one may question whether they truly represent Layer 2. Diagenetic K-feldspar from the upper contact of the sill gives a K-Ar age of 58 ± 2 m.y., so the age is probably late Cretaceous.

Site 170: A sediment section of brown clay, mudstone, and sandstone, all with moderate to abundant volcanic components, includes Mugearite-bearing horizon and overlies a highly altered sill of ocean island tholeiite or alkali basalt at the bottom of the hole. Deeper sediments and oceanic crust were not penetrated. The mugearite, found as fragments in a core catcher sample, may represent a flow, sill, or clasts in a gravelly turbidite. The ocean floor at this site is not a seamount, so, if the mugearite is a flow or sill, it indicates derivation of highly differentiated magmas of this type directly from the mantle. Unlike the zeolitized hawaiites with fresh pyroxene at Hole 165A, the mugearite contains fresh plagioclase, moderate amounts of montmorillonite, and no pyroxene; it appears to have suffered its moderate alteration under conditions of high CO2 activity. The sill beautifully displays diffusioncontrolled diagenetic alteration fronts of various types.

317A (Manihiki Plateau). The thick section of volcanogenic sediments at the bottom of the hole which are barren of datable fossils for nearly 200 meters above basaltic basement. The lowest fossil date is lower/upper Aptian boundary (107 Ma). The potassium-argon date for basaltic basement has a probable age of crystallization of 100-120Ma.
http://www.agu.org/pubs/crossref/1976/JB081i023p04207.shtml - There is an inclination discrepancy between hole 317A carbonate and hole 317A basalt as reported by Cockerham and Jarrard [1976]. Hole 317A basalts have reversible Js-T curves and Curie temperatures of about 570°C. Some 317A basalts have a secondary Curie temperature at about 360°C. The two Curie temperatures in a sample are believed to represent two compositionally different titanomagnetites. Under reflected light, class 3–4 deuterically oxidized titanomagnetite grains are observed with abundant ilmenite exsolution lamellae. These basalts are very resistant to AF demagnetization (median destructive field (MDF) values of ∼250 Oe). A mean inclination of −65.2° (σ = 6.1) has been calculated for these basalts, while the overlying carbonate sediments have a 20° shallower inclination (Ī = 46.7, σ = 9.0). Volcaniclastic sediments, 250 m in thickness, separate the basalts from the carbonates. The mean inclination of the volcaniclastics is −62.2° (σ = 2.4); however, the lowest samples of the carbonates together with the uppermost volcaniclastic samples have inclinations that systematically span the 20° difference. The difference in inclinations of the carbonates and the basalts is believed to be a result of tectonic tilting. The remains of shallow water molluscan fauna, volcaniclastics derived from hyaloclastite eruptions, and the magnetic properties of 317A basalts all suggest a subaerially or very shallow water (<200m) eruption of the 317A basalts.

DSDP Leg 62 Hole-463
2. SITE 463: WESTERN MID-PACIFIC MOUNTAINS1
Shipboard Scientific Party2
http://www.deepseadrilling.org/62/volume/dsdp62_02.pdf
Sedimentation during the late Santonian and most of the Campanian appears to have been very reduced, having a low value of 2 m/m.y. This was followed by an abrupt and marked increase during the late Campanian and early Maastrichtian. Sediments were deposited during that time at an average rate of 42 m/m.y. This high value may result from the equatorial crossing of the site at this time, according to the Lancelot and Larson (1975) tectonic model for Pacific Plate motion (Fig. 21). It is also noticeable that an influx of displaced shallowwater benthic foraminifers occurred in the sediments deposited during that interval of high accumulation rate.
A major hiatus of 17 m.y. spans the Cretaceous/Tertiary boundary. Sedimentation resumed very slowly in the late early Eocene. During the remainder of the Paleogene, sediments accumulated at the very reduced average rate of 0.5 m/m.y. Although a number of fossil zones were recognized in their normal sequential order, some hiatuses may have occurred during that interval of time.
After a major hiatus of 16 m.y., spanning the late Oligocene and the entire early and middle Miocene, sedimentation resumed again in the late Miocene. It was accompanied by reworking of sediments deposited during the preceding time of slow deposition or nondeposition at the site (Late Cretaceous, Eocene, Oligocene,
early and middle Miocene). From that time, sedimentation appears to have been undisturbed and continuous through the late Miocene to Pleistocene, although very slow (average rate 3.5 m/m.y.).

ODP Leg 143 Site 866
Beginning in the Middle Coniacian, an anoxic event (OAE-3) occurred in the Atlantic Ocean, causing large scale deposition of black shales in the Atlantic domain. The anoxic event lasted till the Middle Santonian (from 87.3 to 84.6 Ma) and is the longest and last such event during the Cretaceous period.
Meyers, P.A.; Bernasconi, S.M. & Forster, A.; 2006: Origins and accumulation of organic matter in expanded Albian to Santonian black shale sequences on the Demerara Rise, South American margin, Organic Geochemistry 37, pp 1816-1830.

ODP Leg 143 Site 865
At Site 865 (Allison Guyot), altered basaltic sills are intrusive into Albian clayey dolomitic limestones between 830 and 870 mbsf. Several lines of evidence indicate that the sediment was unconsolidated at the time of invasion by the basat (< lll Ma). Salitic clinopyroxenes, abundances and ratios of the less mobile incompatible elements, and pronounced light rare earth element-enrichment all point to a decidedly more alkalic affinity than was seen at Site 866. Resolution and Allison guyots probably originated within the region of intense hotspot volcanism referred to as the South Pacific isotopic and thermal anomaly or SOPITA.

ODP Leg 143 Site 871
Shipboard Scientific Party, 1993. Site 871. In Premoli Silva, I., Haggerty, J., Rack, F., et al., Proc. ODP, Init. Repts., 144: College Station, TX (Ocean Drilling Program), 41–103. doi:10.2973/odp.proc.ir.144.104.1993 http://dx.doi.org/10.2973/odp.proc.ir.144.104.1993 HOLE 871A Date occupied: 23 May 1992 Date departed: 25 May 1992 Time on hole: 12 hr, 15 min Position: 5°33.432'N, 172°20.658'E Bottom felt (rig floor, m; drill-pipe measurement): 1265.5 Distance between rig floor and sea level (m): 10.9 Water depth (drill-pipe measurement from sea level, m): 1254.6 Total depth (rig floor, m): 1417.4 Penetration (m): 151.9 Number of cores (including cores with no recovery): 17 Total length of cored section (m): 151.90 Total core recovered (m): 126.05 Core recovery (%): 83 Oldest sediment cored: Depth (mbsf): 151.9 Age: middle Eocene
HOLE 871B Date occupied: 25 May 1992 Date departed: 25 May 1992 Time on hole: 12 hr, 15 min Position: 5°33.432'N, 172°20.658'E Bottom felt (rig floor, m; drill-pipe measurement): 1264.9 Distance between rig floor and sea level (m): 10.9 Water depth (drill-pipe measurement from sea level, m): 1254.0 Total depth (rig floor, m): 1417.3 Penetration (m): 152.4 Number of cores (including cores with no recovery): 17 Total length of cored section (m): 152.40 Total core recovered (m): 103.94 Core recovery (%): 68.2 Oldest sediment cored: Depth (mbsf): 152.4 Age: middle Eocene HOLE 871C Date occupied: 26 May 1992 Date departed: 31 May 1992 ' Premoli Silva, I., Haggerty, J., Rack, R, et al., 1993. Proc. ODP, Init. Repts., 144: College Station, TX (Ocean Drilling Program). ~ Shipboard Scientific Party is as given in the list of participants preceding the contents. Time on hole: 5 days, 1 hr, 15 min Position: 5°33.438'N, 172°20.658'E Bottom felt (rig floor, m; drill-pipe measurement): 1265.5 Distance between rig floor and sea level (m): 10.9 Water depth (drill-pipe measurement from sea level, m): 1254.6 Total depth (rig floor, m): 1735.5 Penetration (m): 500.0 Number of cores (including cores with no recovery): 40 Total length of cored section (m): 376.00 Total core recovered (m): 54.79 Core recovery (%): 14.6 Oldest sediment cored: Depth (mbsf): 451.6 Nature: mottled red and gray clay with volcanic clasts Age: early late Paleocene Measured velocity (km/s): 4.0-4.3 Hard rock: Depth (mbsf): 451.5 Nature: basalt Measured velocity (km/s): 4.0-4.7 Basement: Depth (mbsf): 451.6 Nature: basalt Measured velocity (km/s): 4.0-4.7

Far-field strain rings
Line
ENTITY = Line
LAYER = GEOG178_31_08_0639_CIRCLES_SHP
ELEVATION = 0
THICKNESS = 0
COLOR = 3

Paths

Major Fractures

Minor Fractures

Congo Basin, Africa
Est. Permian-Triassic boundary

Congo Basin

Polyline

Crater, ~750 km

Shaanxi and Ordos Basin, China
Pre-Mesozoic (?) age
est. 400-km diameter, unexposed
Proceedings Vol. 7110
Remote Sensing for Environmental Monitoring, GIS Applications, and Geology VIII, Ulrich Michel; Daniel L. Civco; Manfred Ehlers; Hermann J. Kaufmann, Editors, 711017
Date: 13 October 2008
Paper Abstract
According to the synthetical analysis of remote sensing information and geophysical data, the late-reformation characteristics of the South Ordos basin in the Late Mesozoic and the Cenozoic is researched with the former research results and the field work. The result shows that the margin and inside of the basin are all reformed since late Mesozoic. Two different kinds of structure belt exist around the Ordos Basin. They are compressional thrust nappe belt and extensional faulted depression belt. The ring structure which is found in the southern Ordos basin has a diameter of more than 300km, and its movement and rotation are on the assumption that the ring has dominated by the mantle plume in the deep earth and relative movement on the surface of earth. It is testified that the ring structure is a relatively independent block, and it is significant for the coexistence of multi-energy resources in the same basin. There are also differences between the south and north part of Ordos basin in large scale lifting. That is the reason why there are differences between the south and north part of Ordos basin in the distribution of mineral resources. The seismic profile and the magnetotelluric sounding data of the ring structure show that there is a high depth of the Moho boundary comparing with the north part of Ordos basin, it convinced us that the mantle plume lifting does exist in the location of ring structure in the south part of Ordos basin. The lifting movement of Ordos basin in the Late Mesozoic and the Cenozoic may be an important factor of the changing channel of Yellow River cross the Ordos basin, it is significant for the formation and evolution of Yellow River.

Coal basin

Deep saline formations

Gas

Oil basin

Shaanxi impact / Ordos basin

Ordos basin
The Ordos Basin is a large-scale sedimentary basin in Northwestern China. The stratigraphic units from bottom to upper are pre-Cambrian metamorphic rocks, lower-Paleozoic carbonate rocks, upper-Paleozoic to Mesozoic clastic rocks and Cenozoic deposits. The total thickness is up to 6000m.
PETROLEUM GEOLOGY OF CHINA
by Zhai Guangming et al .1997
.3 .4 .1 The Ordos oil and gas sub-province.
The Ordos sub-province includes the eastern Gansu Province, Ningxia Autonomous Region , the northern Shaanxi Province , Shanxi Province, the cent ral Inner Mongolia and the western margin of the Hebei Province, occupying a total area of 930000 km2. The Ordos sub-province is the most stable region of the steady Cent ral China province . Its main part is the Ordos basin, around which to the north, west and south sides distribute the Cenozoic graben systems, such as the Hetao, Yingchuan , Liupan and Weihe basins . To the east side, the Xinshui basin is the bigger one on the Taihang uplift belt .
The main body of the Ordos sub-province is a stable platform, which has a crystalline basement of the Archean to the Early Proterozoic age . The gravity field nearly in the N-S direction descends from the east to the west , surrounding by the gravity gradient in the margin . The crustal thickness is constant , which increases gradually from 36 km in the east to 43 km in the west , and again decreases to 40 km in the northwestern margin . In the Ordos basin that is the main part of the platform, the age of the crystalline basement is older in the north and younger in the south, being respectively the Archean and the Lower Proterozoic metamorphic rocks . The metamorphism degree is higher in the north and lower in the south .The top of the basement shows a framework of alternating uplifts and depressions with NE to N-S trend , and the cover is a westward dipping slope in the general shape .The Tertiary only dist ributes in the footwall of the N-S-trending Liupan Mountain thrust belt in the western margin , the southern margin of the Yingshan Mountain in the north and the northern margin of the Qinling Mountain in the south , all of which are long and narrow faulted-depressions .

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