Eastern Granite-Rhyolite Province (Basement)
This is an informal unit. A formal description has not been peer-reviewed or published.
Freiburg, J.T. et al., Petrology, geochronology, and geophysical characterization of Mesoproterozoic rocks in central Illinois, USA, Geoscience Frontiers, https://doi.org/10.1016/j.gsf.2019.07.004
Extent and thickness
The Precambrian basement of most of the Illinois Basin is referred to as the Eastern Granite-Rhyolite Province (EGRP), which occurs from western Ohio and Kentucky westward to Missouri, Kansas, and Oklahoma (Denison et al., 1987). Zircon U-Pb ages for the EGRP range from 1.35 Ga to 1.55 Ga (Hoppe et al., 1983; Bickford et al., 1986; Hoffman, 1989; Van Schmus et al., 1996). The EGRP belt stretches SW–NE across the southern and eastern parts of the United States and is interpreted as a juvenile terrane accreted to the margin of the Laurentian continent (Whitmeyer and Karlstrom, 2007). A proposed crustal terrane boundary has been identiﬁed by using Nd model ages with protolith ages older than 1.55 Ga on the northwestern side and younger than 1.55 Ga to the southeast (Van Schmus et al., 1996). This Nd boundary runs SW–NE through central Illinois, near the IBDP–ICCS site.
The EGRP is characterized by undeformed and mostly unmetamorphosed rhyolite to dacite with granite of extensional or intraplate (i.e., anorogenic) tectonic origin (Bickford et al., 1986). A-type granites were intruded within the EGRP between 1.48 Ga and 1.35 Ga and occur (Van Schmus et al., 1996) in older Paleo- and Mesoproterozoic crust to the north and west (Karlstrom and Humphreys, 1998; Van Schmus et al., 1996; Whitmeyer and Karlstrom, 2007). Juvenile EGRP volcanic and intrusive rocks crop out in southeastern Canada (Dickin and Higgins, 1992; Gower and Tucker, 1994; Rivers, 1997), the St. Francois Mountains of Missouri (Bowring et al., 1992; Van Schmus et al., 1996), northwestern Texas (Patchett, 1989; Mosher, 1998; Barnes et al., 1999), southern New Mexico (Barnes et al., 1999), and parts of northern Mexico (Patchett and Ruiz, 1989).
Well log characteristics
Age and correlation
The Proterozoic tectonic evolution of Laurentia is complicated and represents more than 800 million years of deformation, crustal forma-tion, southward growth, and metamorphism (Whitmeyer and Karlstrom, 2007). These Proterozoic orogenic belts extend thousands of kilometers from Arizona to Labrador. This southward growth began with two cycles of accretionary orogenesis, beginning with the Yavapai Orogeny ca. 1800–1700 Ma and concluding with the Mazatzal Orogeny from 1700 Ma to 1600 Ma (Karlstrom and Bowring, 1988; Bowring and Karlstrom, 1990; Whitmeyer and Karlstrom, 2007). These two belts are collectively as much as 1000 km (621 mi) wide and are composed largely of juvenile crust (Hill and Bickford, 2001; Whitmeyer and Karlstrom, 2007). The Yavapai and Mazatzal events were followed by widespread, obscure, and enigmatic felsic volcanism and granitic magmatism from 1480 Ma to 1360 Ma, which is collectively referred to as the Midcontinent Granite-Rhyolite (MCGR) province (Lidiak et al., 1966; Van Schmus et al., 1975, 1996; Hoppe et al., 1983; Bickford et al., 1986, 2015; Bowring et al., 1992; Dewane and Van Schmus, 2007). The development of the Laurentian basement culminated with the Grenville Orogeny and the assembly of Rodina from 1300 Ma to 1000 Ma (Dalziel, 1991; Moores, 1991; Craddock et al., 2017a).
Environments of deposition
Seismic reﬂection data reveal the EGRP as being structurally complex in Illinois (Pratt et al., 1989). Before the Paleozoic Illinois Basin formed, a similar structural depression, referred to as the proto-Illinois Basin, formed between 1.48 Ga and 500 Ma (Kolata and Nelson, 2010) and may be evidence of rifting in central Illinois (Marshak and Paulsen, 1996). Despite the lack of drill holes penetrating Precambrian rocks perceived to be part of the proto-Illinois Basin, evidence for the early basin is two-fold:
- (1) A prominent layered sequence of subhorizontal seismic reﬂectors appears to sag into a depression that lies north of the Illinois Basin depocenter (McBride et al., 2003). This layered succession is referred to as the Centralia sequence (Pratt et al., 1989, 1992) and exhibits a geometry that strongly suggests a succession of layered rocks that have been postulated as sedimentary or volcanic in origin (McBride and Kolata, 1999).
- (2) The Centralia sequence is overlain by the Mt. Simon Sandstone, which has a depocenter in east-central Illinois approximately 300km (186 mi) north of the post-Mt. Simon Paleozoic sediment depocenter (the Illinois Basin in southern Illinois; Freiburg et al., 2014). The thickness trends of the Mt. Simon roughly coincide with that of the underlying Centralia succession, suggesting a similar subsidence event that accommodates both units (McBride et al., 2003). Prominent pinch-out boundaries of the Centralia sequence are observed on seismic proﬁles in west-central and south-central Illinois (Pratt et al., 1989; McBride and Kolata, 1999; McBride et al., 2003) and may correspond to a rift boundary, as marked by the Nd line of Van Schmus et al. (1996) and McBride et al. (2016).
The Centralia sequence (as mentioned above), is defined by seismic reflection. It's lithology is not well defined.
- Barnes, M.A., C.R. Rohs, E.Y. Anthony, W.R. Van Schmus, and R.E. Denison, 1999, Isotopic and elemental chemistry of subsurface Precambrian igneous rocks, west Texas and eastern New Mexico: Rocky Mountain Geology, v. 34, p. 245–262.
- Bickford, M.E., W.R. Van, and I. Zietz, 1986, Proterozoic history of the midcontinent region of North America: Geology, v. 14, p. 492–496.
- Bickford, M.E., W.R. Van Schmus, K.E. Karlstrom, P.A. Mueller, and G.D. Kamenov, 2015, Mesoproterozoic–trans-Laurentian magmatism: a synthesis of continent-wide age distributions, new SIMS U-Pb ages, zircon saturation temperatures, and Hf and Nd isotopic compositions: Precambrian Research, v. 265, p. 286–312.
- Bowring, S.A., and K.E. Karlstrom, 1990, Growth, stabilization, and reactivation of Proterozoic lithosphere in the southwestern United States: Geology, v. 18, p. 1203–1206.
- Bowring, S.A., T.B. Housh, W.R. Van Schmus, and F.A. Podosek, 1992, A major Nd isotopic boundary along the southern margin of Laurentia: Eos, v. 73, p. 333.
- Craddock, J.P., S.D. Craddock, A. Konstantinou, A.R. Kylander-Clark, and D.H. Malone, 2017a, Calcite twinning strain variations across the Proterozoic Grenville orogen and Keweenaw-Kapuskasing inverted foreland, USA and Canada. Geoscience Frontiers, v. 8, p. 1357–1384.
- Dalziel, I.W., 1991, Pacific margins of Laurentia and East Antarctica–Australia as a conjugate rift pair: evidence and implications for an Eocambrian supercontinent: Geology, v. 19, p. 598–601.
- Denison, R.E., M.E. Bickford, E.G. Lidiak, and E.B. Kisvarsanyi, 1987, Geology and Geochronology of Precambrian Rocks in the Central Interior Region of the United States: U.S. Geological Survey, Professional Paper 1241-C.
- Dewane, T.J., and W.R. Van Schmus, 2007, U–Pb geochronology of the Wolf River batholith, north-central Wisconsin: evidence for successive magmatism between 1484 Ma and 1468 Ma: Precambrian Research, v. 157, p. 215–234.
- Dickin, A.P., and M.D. Higgins, 1992, Sm/Nd evidence for a major 1.5 Ga crust-forming event in the central Grenville province: Geology, v. 20, p. 137–140.
- Freiburg, J.T., D.G. Morse, H.E. Leetaru, R.P. Hoss, and Q. Yan, 2014, A Depositional and Diagenetic Characterization of the Mt. Simon Sandstone at the Illinois Basin – Decatur Project Carbon Capture and Storage Site, Decatur, Illinois, USA: Illinois State Geological Survey, Circular 583, 59 p. and 3 digital appendices.
- Gower, C.F., and R.D. Tucker, 1994, Distribution of pre-1400 Ma crust in the Grenville province: implications for rifting in Laurentia-Baltica during geon 14: Geology, v. 22, p. 827–830.
- Hill, B.M., and M.E. Bickford, 2001, Paleoproterozoic rocks of central Colorado: accreted arcs or extended older crust?: Geology, v. 29, p. 1015–1018.
- Hoffman, P.F., 1989. Precambrian geology and tectonic history of North America, in Bally, A.W., and A.R. Palmer, eds., The Geology of North America—An Overview. Decade of North American Geology, Volume A: Geological Society of America, p. 447–512.
- Hoppe, W.J., C.W. Montgomery, and W.R. Van Schmus, 1983, Age and significance of Precambrian basement samples from northern Illinois and adjacent states. Journal of Geophysical Research, Solid Earth v. 88, p. 7276–7286.
- Karlstrom, K.E., and S.A. Bowring, 1988, Early Proterozoic assembly of tectonostratigraphic terranes in southwestern North America: Journal of Geology, v. 96, p. 561–576.
- Karlstrom, K.E., and E.D. Humphreys, 1998, Persistent influence of Proterozoic accretionary boundaries in the tectonic evolution of southwestern North America: Rocky Mountain Geology, v. 33, p. 161–179.
- Kolata, D.R., and W.J. Nelson, 2010, Tectonic history, in Kolata, D.R., and C.K. Nimz eds., Geology of Illinois, Illinois State Geological Survey, p. 77–89.
- Lidiak, E.G., R.F. Marvin, H.H. Thomas, and M.N. Bass, 1966, Geochronology of the midcontinent region of the United States: Part 4. Eastern region: Journal of Geophysical Research, v. 71, p. 5427–5438.
- Marshak, S., and T. Paulsen, 1996, Midcontinent US fault and fold zones: a legacy of Proterozoic intracratonic extensional tectonism?: Geology, v. 24 (2), p. 151–154.
- McBride, J.H., and D.R. Kolata, 1999, Upper crust beneath the central Illinois basin, United States: Geological Society of America Bulletin, v. 111, p. 375–394.
- McBride, J.H., D.R. Kolata, and T.G. Hildenbrand, 2003, Geophysical constraints on understanding the origin of the Illinois basin and its underlying crust: Tectonophysics, v. 363, p. 45–78.
- McBride, J.H., H.E. Leetaru, R.W. Keach, and E.I. McBride, 2016, Fine-scale structure of the Precambrian beneath the Illinois basin: Geosphere, v. 12, p. 585–606.
- Moores, E.M., 1991, Southwest US-East Antarctic (SWEAT) connection: a hypothesis: Geology, v. 19, p. 425–428.
- Mosher, S., 1998, Tectonic evolution of the southern Laurentian Grenville orogenic belt: Geological Society of America Bulletin, v. 110, p. 1357–1375.
- Patchett, P.J., 1989, Radiogenic isotope geochemistry of rare earth elements: Reviews in Mineralogy and Geochemistry, v. 21, p. 25–44.
- Patchett, P.J., and J. Ruiz, 1989, Nd isotopes and the origin of Grenville-age rocks in Texas: implications for Proterozoic evolution of the United States mid-continent region: Journal of Geology, v. 97, p. 685–695.
- Pratt, T., R. Culotta, E. Hauser, D. Nelson, L. Brown, S. Kaufman, and W. Hinze, 1989, Major Proterozoic basement features of the eastern midcontinent of North America revealed by recent COCORP profiling: Geology, v. 17, p. 505–509.
- Pratt, T.L., E.C. Hauser, and K.D. Nelson, 1992, Widespread buried Precambrian layered sequences in the US Mid-Continent: evidence for large Proterozoic depositional basins: American Association of Petroleum Geologists Bulletin, v. 76, p. 1384–1401.
- Rivers, T., 1997, Lithotectonic elements of the Grenville province: review and tectonic implications: Precambrian Research, v. 86, p. 117–154.
- Van Schmus, W.R., L.G. Medaris Jr., and P.O. Banks, 1975, Geology and age of the wolf river batholith, Wisconsin: Geological Society of America Bulletin, v. 86, p. 907–914.
- Van Schmus, W.R., M.E. Bickford, and A. Turek, 1996, Proterozoic geology of the east-central midcontinent basement, in Geological Society of America Special Paper, v. 308, p. 7–32.
- Whitmeyer, S.J., and K.E. Karlstrom, 2007, Tectonic model for the Proterozoic growth of North America: Geosphere, v. 3, p. 220–259.
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