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geochemical classification of sedimentary basins
Sedimentary Geology, 69 (1990) 1-6
1
Elsevier Science Publishers B.V., Amsterdam
ExpresSed Maturation-based geodynamic/geochemical classification of sedimentary basins George deV. Klein Department of Geology, University of Illinois at Urbana-Champaign, 245 Natural History Building, 1301 West Green St, Urbana, IL 61801-2999, U.S.A. Received September 17, 1990; revised and accepted October 15, 1990
ABSTRACT Klein, G. deV., 1990. Maturation-based geodynamic/geochemical classification of sedimentary basins. Sediment. Geol., 69: 1-6. Geodynamic principles and processes are combined with continental margin type, basin position on a plate, and crustal type to classify sedimentary basins in a tectonic mode. Tectonic basin classifications, however, have not improved the rate of discovery of hydrocarbons or mineral deposits in sedimentary basins. To improve prediction of commercial hydrocarbon occurrence and sedimentary-hosted ore deposits, it is recommended that the proposed geodynamic basin classification could be combined with organic (petroleum) or inorganic (metals) geochemical classification systems. Organic geochemical basin classification discriminates basin types using three criteria: charge factors, migration drainage factors and impedance factors (Demaison and Huizinga, 1989a, b). A similar approach is applicable to mineral deposits. An inorganic geochemical classification is proposed that recognizes three criteria of inorganic maturation: metal solubility factor, migration drainage factor, and environmental potential for mineral precipitation. This combined geodynamic and geochemical maturation approach to basin classification should enhance resource exploration efficiency.
Introduction A continuing goal in exploration programs is improving the predictability of resource occurrence and discovery rate. To this end, several tectonically oriented classifications of sedimentary basins were proposed, but as both Bally and Snelson (1980) and Demaison and Huizinga (1989a, b) demonstrated, tectonic basin classification has not improved resource discovery rate. Organic geochemical basin classifications, based on concepts of organic geochemistry, were proposed (Demaison and Huizinga, 1989a, b) to improve prediction in oil exploration. Comparable inorganic geochemical basin classification for mineral exploration in sedimentary basins is non-existent, although Large (1988) suggested that basin-forming processes could be considered during mineral exploration programs, and Knight (1957) and White 0037-0738/90/$03.50
© 1990 - Elsevier Science Publishers B.V.
(1968) proposed aspects of ore-forming processes some time ago that constitute a potential inorganic maturation concept. This paper proposes a combined approach to sedimentary basin classification that incorporates developments in the field of geodynamics with both organic and inorganic geochemical maturation concepts. Combining organic maturation concepts and geodynamic basin classification is expected to improve prediction of hydrocarbon occurrences. Similarly, combining a parallel inorganic maturation concept with geodynamic basin classification is expected to improve prediction of ore deposit occurrences in sedimentary basins. Geodynamic basin classification During the past 20 years, several tectonic basin classification were proposed, including some that
2
were
, ; d,'\
oriented
toward
the
petroleum
industry.
KI I i'-
(1988). T h e s e r e s e a r c h e r s p r o p o s e d s e v e r a l c r i t e r i a
Tectonic classifications include those of Dickinson
of basin classification, but the criteria common
(1974), K l e m m e , (1975), B a l l y a n d S n e l s o n (1980).
all a r e (1) t h e n a t u r e o f t h e c o n t i n e n t a l m a r g i n a~
K i n g s t o n et al. (1983), M i a l l ( 1 9 8 4 ) a n d I n g e r s o l l
t h e t i m e o f b a s i n f o r m a t i o n , (2) p o s i t i o n o f a b a s r a
TABLE i Basin classification proposed in this paper Continental margin
Basin type
Basin position on or within plate
Crustal type a
Geodynamic model of formation
Selected examples
Plate interior
cratonic basin
interior
C
extension, stretching, thermal subsidence
Illinois, Michigan and Williston basins
Passive margin
rift basin
interior and edge (parallels margin)
C&T
extension, stretching, thermal subsidence
Gregory Rift, Newark Basin, Rhine Graben
aulacogen
edge to interior (perpendicular to margin)
T &C
extension, stretching, thermal subsidence
Oklahoma Aulacogen, Benue Trough
flexure basin
edge
C
loading, flexure
Baltimore Canyon Trough
trench basin
edge
O
convergence; compression
Sagami Trough, Suraga Trough
trench slope basin
edge
O or older sediment
compression-extension, folding
Trench wall of Mariana and Tonga trenches
forearc basin
off edge
O or older sediment
compression, hthospheric doubling, asymmetric thermal subsidence
Great Valley Basin
intra-arc basin
arc
C-magmatic
extension-rifting
Nigata Basin, Hokkaido Basin
backarc (interarc) basin
interior
O
rifting, stretching, thermal decay
Shikoku Basin, West Philippine Basin
pull-apart basin
transform edge (releasing bend)
C / T or O
translation, extension, thermal subsidence
Ridge Basin, Los Angeles Basin
transpressional basin
transform edge (restraining bend)
C / T or O
translation, thermal subsidence
Ventura Basin, St. George Basin
foreland basin
interior
annealed C & O compressional folding, or C & C loading, flexure
Powder River Basin, Appalachian Basin
superposed (or collage) basin
suture
C / T or O
compression
Tyaughton-Methow Basra
interior or edge
C / T or O
multiple
Illinois Basin
successor basin
interior or edge
C / T or O
multiple
Bowser Basin, Sustut Basin, Dezadeash Basin
resurgent basin
interior or edge
C / T or O
multiple
Fundy Basin
Active margin
Transform margin
Collision margin
polyhistory basin: (Margin independent)
a Crustal type: C = continental; T = transitional; O = oceanic.
to
MATURATION-BASEDGEODYNAMIC/GEOCHEMICAL CLASSIFICATION OF SEDIMENTARY BASINS
on or within a tectonic plate, and (3) nature of the crust flooring the basin (see Klein, 1987, 1991a, b for a review). Helwig (1985) suggested a geodynamic approach to basin classification separating extensional from compressional basins. Klein (1987) incorporated geodynamic processes, and modeling studies into a preliminary classification with the three criteria developed by earlier proponents of basin classification; this classification has been revised (Klein, 1991a, b) and is summarized in Table 1. The principal criteria used to classify basins (Table 1) are: (1) nature of the margin (active, passive, transform, collision, plate interior), (2) position on or within a tectonic plate (interior, edge, off-edge, suture zone), and basin orientation, (3) nature of the crust (continental, oceanic, transitional), and (4) geodynamic process of basin formation (rifting, stretching, extension, flexure, compression, translation, thermal decay). The first three criteria are the those of Dickinson (1974), Klemme (1975) and Bally and Snelson (1980). Dickinson's (1974) intermediate classes of crust are combined into a single transitional class, as suggested by Bally and Snelson (1980) and Klemme (1975). The geodynamic criteria are tectonic processes inferred from geological and geophysical mapping, and results of mathematical and physical modeling (McKenzie, 1978; Jordan, 1981; Beaumont et al., 1982; Watts et al., 1982, DeRito et al., 1983; Hellinger and Sclater, 1983; Auboin et al., 1984; Kobayashi, 1984; Howell et al., 1988; and Yamaji, 1990, amongst many others). These geodynamic factors distinguish between classes of basins with common features, that differ in structural boundary conditions. The salient features of each of the sedimentary basin classes are summarized with examples in Table 1. Details concerning the origin of each of these basin classes are discussed by Klein (1991a, b) with additional references (see also, Klein, 1991c).
Coupling geodynamic and geochemical basin classifications My proposed geodynamic basin classification (Table 1) is useful for comparison of tectonic
3
styles. Bally and Snelson (1980) and Demaison and Huizinga (1989a, b) reported that tectonic basin classifications failed to predict commercial occurrences of hydrocarbons, because correlation of tectonics and geodynamic processes with maturation processes in different basins is incomplete and tectonic and geodynamic processes alone do not control formation and distribution of hydrocarbons. Demaison and Huizinga (1989a, b) suggested an organic geochemical approach to basin classification using three criteria: (1) charge factor (basin thermal history), (2) migration factor (including distribution of porosity and permeability), and (3) impedance factor (seals). These represent degrees of maturation by thermal heating, nature of the migration pathways, and whether or not an adequate seal developed over a potential petroleum reservoir, respectively (Table 2). The charge factor measures to what extent thermal basin processes heated a petroleum source bed sufficiently to generate petroleum. Three classes exist. The undercharged basin is one where maturation is incomplete and although oil shows may occur, maturation was insufficient to generate a commercial quantity of oil. The "normally" charged basin shows a geothermal gradient and heat flow that generated petroleum in sufficient quantity to develop commercial oil fields. The supercharged basin is one in which heat flow and thermal gradient was so large that petroleum was generated rapidly and may have been converted to gas or destroyed. The migration factor may be either vertical or lateral. Vertical migration is common to rifted basins, and occurs mostly along faults, and narrow downward-cutting, stacked and multi-storied TABLE 2 Organic geochemical basin classification (after Demaison and Huizinga, 1989a, b) Charge factor
Migration drainage factor
Entrapment factor
Undercharged
vertically drained
low impedance
Normally charged
laterally drained
high impedance
Supercharged
channels. Lateral migration is more likely to occur in foreland basins, platform settings, or cratonic basins. The geometry of the depositional systems representing conduits to reservoir beds will determine the migration factor and is influenced partly by tectonics. The impedance factor measures the effectiveness of the trapping mechanism and may be either high impedance, which seals a reservoir, or low impedance, which permits petroleum to leak from a reservoir. This property is a function of contrasting lithologies interbedded with or overlying potential reservoirs. Shales and evaporites tend to provide the best impedance for oil occurrences. Thus a basin could be characterized as normally charged, vertically drained, with high impedance, using Table 2. In a petroleum basin assessment study, the geodynamic classification (Table 1) could be combined with an organic geochemical classification (Table 2). For example, the Los Angeles Basin is classified as a supercharged, vertically drained, high impedance, pull-apart basin and the Appalachian Basin is a normally charged, laterally drained, high impedance foreland basin (Demaison and Huizinga, 1989b). The Triassic basins of eastern North America are undercharged, vertically drained, low impedance rift basins. The Illinois Basin is a normally charged, laterally drained, high impedance, polyhistory cratonic basin. Although no formal attempt was made to classify sedimentary basins in terms of inorganic geochemical maturation processes that influence sedimentary ore deposition, both Knight (1957) and White (1968) provided a conceptual framework for developing an inorganic geochemical maturation concept. Both Knight (1957) and White (1968) stressed the importance of a source bed from which metals can be extracted and concentrated elsewhere. This metal source bed concept is comparable to the petroleum source bed concept. White (1968) stressed the role of dissolution of metals by a fluid. Such a fluid migrated from the source bed to a locality where a sediment-hosted ore body could form (White, 1968). Ore body formation occurred in an environment where metal precipitation is favored (White, 1968)
Inorganic geochemical ore-bearing maturation ['actors therefore include: (1) solubility and leaching factor of metalliferous source rocks by potential ore-bearing fluids, (2) migration and drainage factor of ore-forming fluid, and (3) environmental potential factor which favors precipitation and concentration of sedimentary ores. These criteria are used to establish an inorganic geochemical basin classification (Table 3) that parallels the organic geochemical basin classification of Demaison and Huizinga (1989a, b). The solubility factor includes Eh, pH, temperature and pressure, and the environmental precipitation factor include Eh, pH, temperature, pressure and the presence of organic and inorganic catalytic sites which favor mineral precipitation. In parallel with petroleum examples, an ore-hosted sedimentary basin could be classified as a normally soluble, laterally drained, low potential foreland basin, or another basin could be classified as an excess soluble, vertically drained, high potential rift basin. For instance, the North Sudetic Basin and the Z i e l o n a - G o r a - W r o c l a w Basin of southwest Poland, which host the copper-enriched ores of the Kupferschiefer (Jowett et al., 1987), are classified as highly soluble, vertically drained, high potential, copper mineralized, rift basins. Similarly, the fluorspar district of southern Illinois and western Kentucky could be classified as a moderately soluble, laterally drained, high potential, fluoritebearing, cratonic basin.
TABLE 3 Inorganic geochemicalbasin classification Metal solubility factor
Migration drainage factor
Environmental potential for mineral precipitation
Low Solubility low potential verticallydrained Moderate Solubility moderate potential laterally drained High Solubility high potential
MATURATION-BASED G E O D Y N A M I C / G E O C H E M I C A L CLASSIFICATION O F SEDIMENTARY BASINS
5
Conclusions
References
A n a l y s i s o f systems o f b a s i n classification has d e m o n s t r a t e d that b e t t e r r e s o l u t i o n b e t w e e n b a s i n t y p e s can b e m a d e b y i n c o r p o r a t i n g an a d d i t i o n a l criterion, b a s i n - f o r m i n g g e o d y n a m i c processes ( T a b l e 1). E x a m i n a t i o n of T a b l e 1 shows that
Auboin, J., Bourgois, J. and Azema, J., 1984. A new type of active margin: convergent-extension margin as exemplified by the Middle America trench of Guatemala. Earth Planet. Sci. Lett., 67: 211-218. Bally, A.W. and Snelson, S., 1980. Realms of subsidence. In: A.D. Miall (Editor), Facts and Principles of World Petroleum Occurrence. Can. Soc. Pet. Geol. Mem., 6: 9-94. Beaumont, C., Keen, C.E. and Boutilier, R., 1982. A comparison of foreland and rift margin sedimentary basins. Philos. Trans. R. Soc. London, Ser. A, 305: 295-317. Demaison, G.J. and Huizinga, B.J., 1989a. Genetic classification of petroleum basins. Bull., Am. Assoc. Pet. Geol., 73: 349 (abstract). Demaison, G.J. and Huizinga, B.J., 1989b. Genetic classification of petroleum basins. Proc. 28th Int. Geol. Congr., 1: 384-385. DeRito, R.F., Cozzarelli, F.A. and Hodge, D.S., 1983. Mechanism of subsidence of ancient cratonic rift basins. Tectonophysics, 94: 141-168. Dickinson, W.R., 1974. Plate tectonics and sedimentation. In: W.R., Dickinson (Editor), Tectonics and Sedimentation. Soc. Econ. Mineral., Spec. Publ., 22: 1-27. Hellinger, S.J. and Sclater, J.G., 1983. Some comments on two-layer extensional models for the evolution of sedimentary basins. J. Geophys. Res., 88: 8251-8269. Helwig, J.A., 1985. Origin and classification of sedimentary basins. Offshore Technol. Conf. Proc., Pap., OTC 4843: 21-32. Howell, D.G., Moore, G.W. and Wiley, T.J., 1988. Tectonics and basin evolution of western North America--an overview. In: D.W. Scholl, A. Grantz and J.G. Vedder (Editors), Geology and Resource Potential of the Continental Margin of Western North America and Adjacent Ocean BasinBeaufort Sea to Baja California. Circum-Pac. Counc. Energy Mineral. Resour., Earth Sci. Ser., 6: 1-15. Ingersoll, R.V., 1988. Tectonics of sedimentary basins. Geol. Soc. Am. Bull., 100: 1704-1719. Jordan, T.E., 1981. Thrust loads and foreland basin evolution, Cretaceous, western United States. Bull. Am. Assoc. Pet. Geol., 65: 83-91. Jowett, E.C., Rydzewski, A. and Jowett, R.J., 1987. The Kupferschiefer Cu-Ag ore deposits in Poland: a re-appraisal of the evidence of their origin and presentation of a new genetic model. Can. J. Earth Sci., 24: 2016-2037. Kingston, D.R., Dishroon, C.P. and Williams, P.A., 1983. Global basin classification system. Bull. Am. Assoc. Pet. Geol., 67: 2175-2193. Klein, G.deV., 1987. Current aspects of basin analysis. Sediment. Geol., 50: 95-118. Klein, G.deV., 1991a. Sedimentary basin classification. In: J.J. Eidel and E.R. Force (Editors), Major sediment-hosted ore deposits: basin analysis and sedimentary processes in mineral exploration. Rev. Econ. Geol., 6 (in press). Klein, G.deV., 1991b. Geodynamic and geochemical aspects of
m a n y of the p r i n c i p a l criteria used for b a s i n classification, n a m e l y n a t u r e of the crust, d i s t a n c e f r o m the p l a t e edge, m a r g i n type a n d b a s i n geodyn a m i c s show some degree of c o m m o n a l i t y a m o n g different s e d i m e n t a r y basins. A d d i t i o n of a geodyn a m i c criterion i m p r o v e s s e p a r a t i o n of p r o t o t y p e b a s i n s into distinct classes. T h e c o n c e p t of p e t r o l e u m
maturation
per-
m i t t e d recognition of organic geochemical b a s i n types ( D e m a i s o n a n d Huizinga,1989a, b). These processes a p p l y also to i n o r g a n i c geochemical reactions which influence the f o r m a t i o n of sediment a r y - h o s t e d ore deposits. Criteria used for ino r g a n i c g e o c h e m i c a l b a s i n classification include the m e t a l solubility factor, the m i g r a t i o n d r a i n a g e factor, a n d the e n v i r o n m e n t a l p o t e n t i a l for m i n e r a l p r e c i p i t a t i o n . A g e o d y n a m i c b a s i n classification ( T a b l e 1) can be c o m b i n e d with either the o r g a n i c geochemical b a s i n classification (Table 2) of Dem a i s o n a n d H u i z i n g a (1989a, b), o r with the p r o p o s e d i n o r g a n i c geochemical b a s i n classification ( T a b l e 3), to i m p r o v e predictive capabilities in petroleum and mineral exploration programs.
Acknowledgements I wish to t h a n k J. J a m e s Eidel for inviting m e to p r e p a r e a c u r r e n t assessment o f b a s i n classification (Klein, 1991a) a n d for s t i m u l a t i n g discussions that p r o m p t e d the i n o r g a n i c geochemical b a s i n classification shown in T a b l e 3. K e v i n T. Biddle, J. J a m e s Eidel, Eric R. Force, Stephen R. J a c o b son, J. Barry M a y n a r d a n d Brian J. Skinner p r o v i d e d helpful, cogent a n d constructive c o m m e n t s on earlier m a n u s c r i p t versions of this paper. I also t h a n k Pat E r i k s s o n for an i n v i t a t i o n to p r e s e n t these basin c o n c e p t s (Klein, 1991b, c) at the S o u t h A f r i c a n P r e c a m b r i a n Basin Conference, a n d for a r r a n g i n g with the U n i v e r s i t y of P r e t o r i a to h o s t m y visit.
classification of sedimentary basins. ,I. Afr. Earth Sci. (in press). Klein, G.deV., 1991c. Origin and evolution of North Amerman cratonic basins. S. Aft. J. Geol. (in presst. Klemme, H.D., 1975. Giant oil fields related to theoir geological setting: a possible guide to exploration. Bull. Can. Soc. Pet. Geol., 23: 30-66. Knight, C.L., 1957. Ore genesis--the source bed concept. Econ. Geol., 52: 808-817. Kobayashi, K., 1984, Subsidence of the Shikoku back-arc basins. Tectonophysics, 102: 105-114. Large, D., 1988. The evaluation of sedimentary basins for masive sulfide mineralization. In: G.H. Friedrich and P.M.
Herzig [t.~ditors), Ba~e Metal Sulfide [.)eposJt~. Sprmgc~ Verlag, New York, N.Y., pp. 3 11 McKenzie, D.I'., 1¢978. Some remark~ on the development ~,t sedimentary basins. Earth Planet. Sci. Lett., 4 0 : 2 5 32. Miall, A.D., 1984. Principles of Sedimentary Basin Analys~s. Springer-Verlag, New York, N.Y., 490 pp. Watts, A.B., Karner, G.D. and Steckler, M.S., 1982. I_,ithospheric flexure and the evolution of sedimentary basin~. Philos. Trans. R. Soc. London, Set. A, 305:249 281. White, D.E., 1968. Environnents of generation of some basemetal ore deposits. Econ. Geol., 63: 301-335. Yamaji, A., 1990. Rapid intra-arc rifting in Miocene, northeast Japan. Tectonics, 9: 365--378.
1
Elsevier Science Publishers B.V., Amsterdam
ExpresSed Maturation-based geodynamic/geochemical classification of sedimentary basins George deV. Klein Department of Geology, University of Illinois at Urbana-Champaign, 245 Natural History Building, 1301 West Green St, Urbana, IL 61801-2999, U.S.A. Received September 17, 1990; revised and accepted October 15, 1990
ABSTRACT Klein, G. deV., 1990. Maturation-based geodynamic/geochemical classification of sedimentary basins. Sediment. Geol., 69: 1-6. Geodynamic principles and processes are combined with continental margin type, basin position on a plate, and crustal type to classify sedimentary basins in a tectonic mode. Tectonic basin classifications, however, have not improved the rate of discovery of hydrocarbons or mineral deposits in sedimentary basins. To improve prediction of commercial hydrocarbon occurrence and sedimentary-hosted ore deposits, it is recommended that the proposed geodynamic basin classification could be combined with organic (petroleum) or inorganic (metals) geochemical classification systems. Organic geochemical basin classification discriminates basin types using three criteria: charge factors, migration drainage factors and impedance factors (Demaison and Huizinga, 1989a, b). A similar approach is applicable to mineral deposits. An inorganic geochemical classification is proposed that recognizes three criteria of inorganic maturation: metal solubility factor, migration drainage factor, and environmental potential for mineral precipitation. This combined geodynamic and geochemical maturation approach to basin classification should enhance resource exploration efficiency.
Introduction A continuing goal in exploration programs is improving the predictability of resource occurrence and discovery rate. To this end, several tectonically oriented classifications of sedimentary basins were proposed, but as both Bally and Snelson (1980) and Demaison and Huizinga (1989a, b) demonstrated, tectonic basin classification has not improved resource discovery rate. Organic geochemical basin classifications, based on concepts of organic geochemistry, were proposed (Demaison and Huizinga, 1989a, b) to improve prediction in oil exploration. Comparable inorganic geochemical basin classification for mineral exploration in sedimentary basins is non-existent, although Large (1988) suggested that basin-forming processes could be considered during mineral exploration programs, and Knight (1957) and White 0037-0738/90/$03.50
© 1990 - Elsevier Science Publishers B.V.
(1968) proposed aspects of ore-forming processes some time ago that constitute a potential inorganic maturation concept. This paper proposes a combined approach to sedimentary basin classification that incorporates developments in the field of geodynamics with both organic and inorganic geochemical maturation concepts. Combining organic maturation concepts and geodynamic basin classification is expected to improve prediction of hydrocarbon occurrences. Similarly, combining a parallel inorganic maturation concept with geodynamic basin classification is expected to improve prediction of ore deposit occurrences in sedimentary basins. Geodynamic basin classification During the past 20 years, several tectonic basin classification were proposed, including some that
2
were
, ; d,'\
oriented
toward
the
petroleum
industry.
KI I i'-
(1988). T h e s e r e s e a r c h e r s p r o p o s e d s e v e r a l c r i t e r i a
Tectonic classifications include those of Dickinson
of basin classification, but the criteria common
(1974), K l e m m e , (1975), B a l l y a n d S n e l s o n (1980).
all a r e (1) t h e n a t u r e o f t h e c o n t i n e n t a l m a r g i n a~
K i n g s t o n et al. (1983), M i a l l ( 1 9 8 4 ) a n d I n g e r s o l l
t h e t i m e o f b a s i n f o r m a t i o n , (2) p o s i t i o n o f a b a s r a
TABLE i Basin classification proposed in this paper Continental margin
Basin type
Basin position on or within plate
Crustal type a
Geodynamic model of formation
Selected examples
Plate interior
cratonic basin
interior
C
extension, stretching, thermal subsidence
Illinois, Michigan and Williston basins
Passive margin
rift basin
interior and edge (parallels margin)
C&T
extension, stretching, thermal subsidence
Gregory Rift, Newark Basin, Rhine Graben
aulacogen
edge to interior (perpendicular to margin)
T &C
extension, stretching, thermal subsidence
Oklahoma Aulacogen, Benue Trough
flexure basin
edge
C
loading, flexure
Baltimore Canyon Trough
trench basin
edge
O
convergence; compression
Sagami Trough, Suraga Trough
trench slope basin
edge
O or older sediment
compression-extension, folding
Trench wall of Mariana and Tonga trenches
forearc basin
off edge
O or older sediment
compression, hthospheric doubling, asymmetric thermal subsidence
Great Valley Basin
intra-arc basin
arc
C-magmatic
extension-rifting
Nigata Basin, Hokkaido Basin
backarc (interarc) basin
interior
O
rifting, stretching, thermal decay
Shikoku Basin, West Philippine Basin
pull-apart basin
transform edge (releasing bend)
C / T or O
translation, extension, thermal subsidence
Ridge Basin, Los Angeles Basin
transpressional basin
transform edge (restraining bend)
C / T or O
translation, thermal subsidence
Ventura Basin, St. George Basin
foreland basin
interior
annealed C & O compressional folding, or C & C loading, flexure
Powder River Basin, Appalachian Basin
superposed (or collage) basin
suture
C / T or O
compression
Tyaughton-Methow Basra
interior or edge
C / T or O
multiple
Illinois Basin
successor basin
interior or edge
C / T or O
multiple
Bowser Basin, Sustut Basin, Dezadeash Basin
resurgent basin
interior or edge
C / T or O
multiple
Fundy Basin
Active margin
Transform margin
Collision margin
polyhistory basin: (Margin independent)
a Crustal type: C = continental; T = transitional; O = oceanic.
to
MATURATION-BASEDGEODYNAMIC/GEOCHEMICAL CLASSIFICATION OF SEDIMENTARY BASINS
on or within a tectonic plate, and (3) nature of the crust flooring the basin (see Klein, 1987, 1991a, b for a review). Helwig (1985) suggested a geodynamic approach to basin classification separating extensional from compressional basins. Klein (1987) incorporated geodynamic processes, and modeling studies into a preliminary classification with the three criteria developed by earlier proponents of basin classification; this classification has been revised (Klein, 1991a, b) and is summarized in Table 1. The principal criteria used to classify basins (Table 1) are: (1) nature of the margin (active, passive, transform, collision, plate interior), (2) position on or within a tectonic plate (interior, edge, off-edge, suture zone), and basin orientation, (3) nature of the crust (continental, oceanic, transitional), and (4) geodynamic process of basin formation (rifting, stretching, extension, flexure, compression, translation, thermal decay). The first three criteria are the those of Dickinson (1974), Klemme (1975) and Bally and Snelson (1980). Dickinson's (1974) intermediate classes of crust are combined into a single transitional class, as suggested by Bally and Snelson (1980) and Klemme (1975). The geodynamic criteria are tectonic processes inferred from geological and geophysical mapping, and results of mathematical and physical modeling (McKenzie, 1978; Jordan, 1981; Beaumont et al., 1982; Watts et al., 1982, DeRito et al., 1983; Hellinger and Sclater, 1983; Auboin et al., 1984; Kobayashi, 1984; Howell et al., 1988; and Yamaji, 1990, amongst many others). These geodynamic factors distinguish between classes of basins with common features, that differ in structural boundary conditions. The salient features of each of the sedimentary basin classes are summarized with examples in Table 1. Details concerning the origin of each of these basin classes are discussed by Klein (1991a, b) with additional references (see also, Klein, 1991c).
Coupling geodynamic and geochemical basin classifications My proposed geodynamic basin classification (Table 1) is useful for comparison of tectonic
3
styles. Bally and Snelson (1980) and Demaison and Huizinga (1989a, b) reported that tectonic basin classifications failed to predict commercial occurrences of hydrocarbons, because correlation of tectonics and geodynamic processes with maturation processes in different basins is incomplete and tectonic and geodynamic processes alone do not control formation and distribution of hydrocarbons. Demaison and Huizinga (1989a, b) suggested an organic geochemical approach to basin classification using three criteria: (1) charge factor (basin thermal history), (2) migration factor (including distribution of porosity and permeability), and (3) impedance factor (seals). These represent degrees of maturation by thermal heating, nature of the migration pathways, and whether or not an adequate seal developed over a potential petroleum reservoir, respectively (Table 2). The charge factor measures to what extent thermal basin processes heated a petroleum source bed sufficiently to generate petroleum. Three classes exist. The undercharged basin is one where maturation is incomplete and although oil shows may occur, maturation was insufficient to generate a commercial quantity of oil. The "normally" charged basin shows a geothermal gradient and heat flow that generated petroleum in sufficient quantity to develop commercial oil fields. The supercharged basin is one in which heat flow and thermal gradient was so large that petroleum was generated rapidly and may have been converted to gas or destroyed. The migration factor may be either vertical or lateral. Vertical migration is common to rifted basins, and occurs mostly along faults, and narrow downward-cutting, stacked and multi-storied TABLE 2 Organic geochemical basin classification (after Demaison and Huizinga, 1989a, b) Charge factor
Migration drainage factor
Entrapment factor
Undercharged
vertically drained
low impedance
Normally charged
laterally drained
high impedance
Supercharged
channels. Lateral migration is more likely to occur in foreland basins, platform settings, or cratonic basins. The geometry of the depositional systems representing conduits to reservoir beds will determine the migration factor and is influenced partly by tectonics. The impedance factor measures the effectiveness of the trapping mechanism and may be either high impedance, which seals a reservoir, or low impedance, which permits petroleum to leak from a reservoir. This property is a function of contrasting lithologies interbedded with or overlying potential reservoirs. Shales and evaporites tend to provide the best impedance for oil occurrences. Thus a basin could be characterized as normally charged, vertically drained, with high impedance, using Table 2. In a petroleum basin assessment study, the geodynamic classification (Table 1) could be combined with an organic geochemical classification (Table 2). For example, the Los Angeles Basin is classified as a supercharged, vertically drained, high impedance, pull-apart basin and the Appalachian Basin is a normally charged, laterally drained, high impedance foreland basin (Demaison and Huizinga, 1989b). The Triassic basins of eastern North America are undercharged, vertically drained, low impedance rift basins. The Illinois Basin is a normally charged, laterally drained, high impedance, polyhistory cratonic basin. Although no formal attempt was made to classify sedimentary basins in terms of inorganic geochemical maturation processes that influence sedimentary ore deposition, both Knight (1957) and White (1968) provided a conceptual framework for developing an inorganic geochemical maturation concept. Both Knight (1957) and White (1968) stressed the importance of a source bed from which metals can be extracted and concentrated elsewhere. This metal source bed concept is comparable to the petroleum source bed concept. White (1968) stressed the role of dissolution of metals by a fluid. Such a fluid migrated from the source bed to a locality where a sediment-hosted ore body could form (White, 1968). Ore body formation occurred in an environment where metal precipitation is favored (White, 1968)
Inorganic geochemical ore-bearing maturation ['actors therefore include: (1) solubility and leaching factor of metalliferous source rocks by potential ore-bearing fluids, (2) migration and drainage factor of ore-forming fluid, and (3) environmental potential factor which favors precipitation and concentration of sedimentary ores. These criteria are used to establish an inorganic geochemical basin classification (Table 3) that parallels the organic geochemical basin classification of Demaison and Huizinga (1989a, b). The solubility factor includes Eh, pH, temperature and pressure, and the environmental precipitation factor include Eh, pH, temperature, pressure and the presence of organic and inorganic catalytic sites which favor mineral precipitation. In parallel with petroleum examples, an ore-hosted sedimentary basin could be classified as a normally soluble, laterally drained, low potential foreland basin, or another basin could be classified as an excess soluble, vertically drained, high potential rift basin. For instance, the North Sudetic Basin and the Z i e l o n a - G o r a - W r o c l a w Basin of southwest Poland, which host the copper-enriched ores of the Kupferschiefer (Jowett et al., 1987), are classified as highly soluble, vertically drained, high potential, copper mineralized, rift basins. Similarly, the fluorspar district of southern Illinois and western Kentucky could be classified as a moderately soluble, laterally drained, high potential, fluoritebearing, cratonic basin.
TABLE 3 Inorganic geochemicalbasin classification Metal solubility factor
Migration drainage factor
Environmental potential for mineral precipitation
Low Solubility low potential verticallydrained Moderate Solubility moderate potential laterally drained High Solubility high potential
MATURATION-BASED G E O D Y N A M I C / G E O C H E M I C A L CLASSIFICATION O F SEDIMENTARY BASINS
5
Conclusions
References
A n a l y s i s o f systems o f b a s i n classification has d e m o n s t r a t e d that b e t t e r r e s o l u t i o n b e t w e e n b a s i n t y p e s can b e m a d e b y i n c o r p o r a t i n g an a d d i t i o n a l criterion, b a s i n - f o r m i n g g e o d y n a m i c processes ( T a b l e 1). E x a m i n a t i o n of T a b l e 1 shows that
Auboin, J., Bourgois, J. and Azema, J., 1984. A new type of active margin: convergent-extension margin as exemplified by the Middle America trench of Guatemala. Earth Planet. Sci. Lett., 67: 211-218. Bally, A.W. and Snelson, S., 1980. Realms of subsidence. In: A.D. Miall (Editor), Facts and Principles of World Petroleum Occurrence. Can. Soc. Pet. Geol. Mem., 6: 9-94. Beaumont, C., Keen, C.E. and Boutilier, R., 1982. A comparison of foreland and rift margin sedimentary basins. Philos. Trans. R. Soc. London, Ser. A, 305: 295-317. Demaison, G.J. and Huizinga, B.J., 1989a. Genetic classification of petroleum basins. Bull., Am. Assoc. Pet. Geol., 73: 349 (abstract). Demaison, G.J. and Huizinga, B.J., 1989b. Genetic classification of petroleum basins. Proc. 28th Int. Geol. Congr., 1: 384-385. DeRito, R.F., Cozzarelli, F.A. and Hodge, D.S., 1983. Mechanism of subsidence of ancient cratonic rift basins. Tectonophysics, 94: 141-168. Dickinson, W.R., 1974. Plate tectonics and sedimentation. In: W.R., Dickinson (Editor), Tectonics and Sedimentation. Soc. Econ. Mineral., Spec. Publ., 22: 1-27. Hellinger, S.J. and Sclater, J.G., 1983. Some comments on two-layer extensional models for the evolution of sedimentary basins. J. Geophys. Res., 88: 8251-8269. Helwig, J.A., 1985. Origin and classification of sedimentary basins. Offshore Technol. Conf. Proc., Pap., OTC 4843: 21-32. Howell, D.G., Moore, G.W. and Wiley, T.J., 1988. Tectonics and basin evolution of western North America--an overview. In: D.W. Scholl, A. Grantz and J.G. Vedder (Editors), Geology and Resource Potential of the Continental Margin of Western North America and Adjacent Ocean BasinBeaufort Sea to Baja California. Circum-Pac. Counc. Energy Mineral. Resour., Earth Sci. Ser., 6: 1-15. Ingersoll, R.V., 1988. Tectonics of sedimentary basins. Geol. Soc. Am. Bull., 100: 1704-1719. Jordan, T.E., 1981. Thrust loads and foreland basin evolution, Cretaceous, western United States. Bull. Am. Assoc. Pet. Geol., 65: 83-91. Jowett, E.C., Rydzewski, A. and Jowett, R.J., 1987. The Kupferschiefer Cu-Ag ore deposits in Poland: a re-appraisal of the evidence of their origin and presentation of a new genetic model. Can. J. Earth Sci., 24: 2016-2037. Kingston, D.R., Dishroon, C.P. and Williams, P.A., 1983. Global basin classification system. Bull. Am. Assoc. Pet. Geol., 67: 2175-2193. Klein, G.deV., 1987. Current aspects of basin analysis. Sediment. Geol., 50: 95-118. Klein, G.deV., 1991a. Sedimentary basin classification. In: J.J. Eidel and E.R. Force (Editors), Major sediment-hosted ore deposits: basin analysis and sedimentary processes in mineral exploration. Rev. Econ. Geol., 6 (in press). Klein, G.deV., 1991b. Geodynamic and geochemical aspects of
m a n y of the p r i n c i p a l criteria used for b a s i n classification, n a m e l y n a t u r e of the crust, d i s t a n c e f r o m the p l a t e edge, m a r g i n type a n d b a s i n geodyn a m i c s show some degree of c o m m o n a l i t y a m o n g different s e d i m e n t a r y basins. A d d i t i o n of a geodyn a m i c criterion i m p r o v e s s e p a r a t i o n of p r o t o t y p e b a s i n s into distinct classes. T h e c o n c e p t of p e t r o l e u m
maturation
per-
m i t t e d recognition of organic geochemical b a s i n types ( D e m a i s o n a n d Huizinga,1989a, b). These processes a p p l y also to i n o r g a n i c geochemical reactions which influence the f o r m a t i o n of sediment a r y - h o s t e d ore deposits. Criteria used for ino r g a n i c g e o c h e m i c a l b a s i n classification include the m e t a l solubility factor, the m i g r a t i o n d r a i n a g e factor, a n d the e n v i r o n m e n t a l p o t e n t i a l for m i n e r a l p r e c i p i t a t i o n . A g e o d y n a m i c b a s i n classification ( T a b l e 1) can be c o m b i n e d with either the o r g a n i c geochemical b a s i n classification (Table 2) of Dem a i s o n a n d H u i z i n g a (1989a, b), o r with the p r o p o s e d i n o r g a n i c geochemical b a s i n classification ( T a b l e 3), to i m p r o v e predictive capabilities in petroleum and mineral exploration programs.
Acknowledgements I wish to t h a n k J. J a m e s Eidel for inviting m e to p r e p a r e a c u r r e n t assessment o f b a s i n classification (Klein, 1991a) a n d for s t i m u l a t i n g discussions that p r o m p t e d the i n o r g a n i c geochemical b a s i n classification shown in T a b l e 3. K e v i n T. Biddle, J. J a m e s Eidel, Eric R. Force, Stephen R. J a c o b son, J. Barry M a y n a r d a n d Brian J. Skinner p r o v i d e d helpful, cogent a n d constructive c o m m e n t s on earlier m a n u s c r i p t versions of this paper. I also t h a n k Pat E r i k s s o n for an i n v i t a t i o n to p r e s e n t these basin c o n c e p t s (Klein, 1991b, c) at the S o u t h A f r i c a n P r e c a m b r i a n Basin Conference, a n d for a r r a n g i n g with the U n i v e r s i t y of P r e t o r i a to h o s t m y visit.
classification of sedimentary basins. ,I. Afr. Earth Sci. (in press). Klein, G.deV., 1991c. Origin and evolution of North Amerman cratonic basins. S. Aft. J. Geol. (in presst. Klemme, H.D., 1975. Giant oil fields related to theoir geological setting: a possible guide to exploration. Bull. Can. Soc. Pet. Geol., 23: 30-66. Knight, C.L., 1957. Ore genesis--the source bed concept. Econ. Geol., 52: 808-817. Kobayashi, K., 1984, Subsidence of the Shikoku back-arc basins. Tectonophysics, 102: 105-114. Large, D., 1988. The evaluation of sedimentary basins for masive sulfide mineralization. In: G.H. Friedrich and P.M.
Herzig [t.~ditors), Ba~e Metal Sulfide [.)eposJt~. Sprmgc~ Verlag, New York, N.Y., pp. 3 11 McKenzie, D.I'., 1¢978. Some remark~ on the development ~,t sedimentary basins. Earth Planet. Sci. Lett., 4 0 : 2 5 32. Miall, A.D., 1984. Principles of Sedimentary Basin Analys~s. Springer-Verlag, New York, N.Y., 490 pp. Watts, A.B., Karner, G.D. and Steckler, M.S., 1982. I_,ithospheric flexure and the evolution of sedimentary basin~. Philos. Trans. R. Soc. London, Set. A, 305:249 281. White, D.E., 1968. Environnents of generation of some basemetal ore deposits. Econ. Geol., 63: 301-335. Yamaji, A., 1990. Rapid intra-arc rifting in Miocene, northeast Japan. Tectonics, 9: 365--378.