Quaternary Displacement on the Joiner Ridge Fault, Eastern Arkansas

2019 ◽  
Vol 90 (6) ◽  
pp. 2250-2261 ◽  
Author(s):  
Audrey C. Price ◽  
Edward W. Woolery ◽  
Ronald C. Counts ◽  
Roy B. Van Arsdale ◽  
Daniel Larsen ◽  
...  
Keyword(s):  
Mississippi River ◽  
Slip Rate ◽  
Radiometric Dating ◽  
Seismic Zone ◽  
S Wave ◽  
Apparent Slip ◽  
Reverse Faulting ◽  
Central United States ◽  
Late Wisconsinan ◽  
Seismic Reflection Profiles

ABSTRACT The New Madrid seismic zone of the central United States is an intraplate seismic zone with blind structures that are not seismically active but may pose seismic hazards. The Joiner ridge fault (JRF) is the 35‐kilometer‐long east‐bounding fault of the Joiner ridge blind horst located in eastern Arkansas ∼50  km northwest of Memphis, Tennessee. Shallow S‐wave (SH‐mode) seismic reflection profiles, continuous cores, and radiometric dating of Quaternary alluvium across the JRF reveal down‐to‐the‐east reverse faulting and folding of Eocene strata and overlying Quaternary Mississippi River alluvium. The base of the Quaternary alluvium has an age of 20.3 ka and is vertically displaced 12 m, resulting in an average slip rate of 0.6±0.1  mm/yr over the past 20.3 ka. The overlying upper Wisconsinan and Holocene alluvial facies are also displaced by the JRF. These facies increase in thickness across the JRF and were used to calculate late Wisconsinan and Holocene slip histories. The JRF slipped 7 m between 20.3 and 17.5 ka, 3 m between 12.3 and 11.5 ka, and 2 m between 11.5 and 8.9 ka. No apparent slip occurred on the JRF within the last 8.9 ka. This research illustrates that slip has been intermittent and that slip magnitudes on the JRF diminished through the late Wisconsinan and early Holocene.

Conditional Mean Spectra in Site-Specific Seismic Hazard Evaluation for a Major River Crossing in the Central United States

2015 ◽  
Vol 31 (1) ◽  
pp. 47-69 ◽  
Author(s):  
Youssef M. A. Hashash ◽  
Norman A. Abrahamson ◽  
Scott M. Olson ◽  
Steve Hague ◽  
Byungmin Kim
Keyword(s):  
Seismic Hazard ◽  
Mississippi River ◽  
Response Spectrum ◽  
Lateral Spreading ◽  
Hazard Evaluation ◽  
Seismic Zone ◽  
Conditional Mean ◽  
Central United States ◽  
Uniform Hazard Response Spectrum ◽  
Geologic Record

Current seismic design practice often relies on the use of the uniform hazard response spectrum (UHRS), which implicitly includes motions from multiple earthquake sources and envelops possible spectra, yet does not represent a single event. Seismic hazard analyses at the site of a major Mississippi River crossing near St. Louis, Missouri, showed bimodal seismic hazard dominated by small, nearby earthquakes at short periods and large, distant earthquakes in the New Madrid seismic zone at long periods. UHRS motions resulted in large seismic demands and predictions of pervasive liquefaction that were inconsistent with historical and geologic records. UHRS-compatible conditional mean spectra (CMS) were developed to bridge deterministic and probabilistic seismic hazard evaluations, and used to evaluate liquefaction, lateral spreading, and settlement potential. The computed response was consistent with the historical and geologic record. CMSs offer hazard-compatible alternatives to the UHRS and result in seismic demand consistent with historical and geologic evidence.

3D GEOLOGIC MAPPING IN AND ADJACENT TO THE NEW MADRID SEISMIC ZONE, CENTRAL UNITED STATES

2020 ◽  
Author(s):  
Renee M. Reichenbacher ◽  
◽  
Valarie Harrison ◽  
Taylor Andrew Weathers ◽  
Roy B. Van Arsdale ◽  
...  
Keyword(s):  
United States ◽  
New Madrid Seismic Zone ◽  
Seismic Zone ◽  
Geologic Mapping ◽  
Central United States ◽  
New Madrid

The Late Wisconsinan Savanna Terrace in Tributaries to the Upper Mississippi River

1983 ◽  
Vol 20 (2) ◽  
pp. 165-176 ◽  
Author(s):  
Mark A. Flock
Keyword(s):  
Mississippi River ◽  
Large Scale ◽  
Lake Superior ◽  
Mississippi Valley ◽  
Red Clay ◽  
Radiocarbon Dates ◽  
Jackson County ◽  
Late Wisconsinan ◽  
Different Sources ◽  
Lacustrine Deposit

The Savanna Terrace, composed of alternating red and gray clayey sediments of late Wisconsinan age, can be found in five states along the upper Mississippi valley from Pepin County, Wisconsin, to Jackson County, Illinois. The terrace is the highest glaciofluvial-lacustrine deposit without a loess cover in the upper Mississippi valley. Chemical, physical, and mineralogical data show that two different sources provided sediment. The red clay is believed to have come from Lake Superior sources, while the gray clay is believed to have come from sources farther west. Large-scale flood events from glacial Lakes Agassiz, Grantsburg, and Superior were probably the main contributors of the sediments. The red clay in the terrace is similar in composition to red glaciolacustrine sediment found in eastern and northern Wisconsin. It also is mineralogically similar to the Hinckley Sandstone and the Fond du Lac Formation, which occur under and around Lake Superior. Radiocarbon dates obtained from the lower Illinois valley indicate that the terrace sediments were deposited sometime between about 13,100 and 9500 yr ago. Soils developed on the terrace are variable in their physical, chemical, and mineralogical properties, which reflect the composition of the clayey sediments.

Coring Archaeological Sites

1986 ◽  
Vol 51 (3) ◽  
pp. 505-527 ◽  
Author(s):  
Julie K. Stein
Keyword(s):  
Mississippi River ◽  
River Sediments ◽  
Radiometric Dating ◽  
Archaeological Sites ◽  
New Device ◽  
Culture History ◽  
Lower Mississippi River ◽  
History Of ◽  
River Deposits ◽  
Relationship Of

The history of coring and augering at archaeological sites is traced to two periods in the twentieth century. In the first period, Period I (1935-1955), the technique was used primarily to correlate archaeological deposits with river sediments for dating purposes. Rarely were the deposits containing artifacts cored or augered; rather the stratigraphic relationship of cultural to non-cultural deposits was sought. Most of this work was done in the Lower Mississippi River Delta where geologists had calculated absolute dates for river deposits. This period seems to have ended with the availability of radiometric dating and was followed by Period II (1964-present). After 1964 there is a renewed interest in coring and augering, mostly following a shift in archaeological research interests from culture history toward ecological questions. This shift coincides with the availability of a new device: a mechanical corer. During Period II, coring is utilized in many different projects, including reconstructing the environment surrounding sites, collection of samples from subsurface deposits, and locating buried archaeological sites. Following the discussion of the history of coring and augering, a description of equipment, techniques, and data potential is presented.

The interrelationship between electrical resistivity and VP/VS ratio: A novel approach to constrain the subsurface resistivity structure in data gap areas in a seismogenic zone

Geophysics ◽  
2021 ◽  
pp. 1-44
Author(s):  
Ujjal K. Borah ◽  
Prasanta K. Patro
Keyword(s):  
Electrical Resistivity ◽  
A Priori ◽  
Fault Zones ◽  
Middle Part ◽  
Seismogenic Zone ◽  
Earth Model ◽  
Seismic Zone ◽  
S Wave ◽  
Data Gap ◽  
Earthquake Zone

Large man-made water-reservoirs promote fluid diffusion and cause critically stressed fault zones underneath to trigger earthquakes. Electrical resistivity is a crucial property to investigate such fluid-filled fault zones. We, therefore, carry out magnetotelluric (MT) investigation to explore an intra-plate earthquake zone, which is related to artificial reservoir triggered seismicity. However, due to surface access restrictions, our dataset has a gap in coverage in the middle part of the study area. This data gap region coincides with the earthquake hypocenter distribution in that intra-plate earthquake zone. Therefore, it is vital to fill the data gap to get the electrical signature of the active seismic zone. To compensate for the data gap, we develop a relation that connects resistivity with the ratio of seismic P- to S-wave velocity ( VP/ VS). Utilizing this relation, we estimate a priori resistivity distribution in the data gap region from known vp/vs values during inversion to compensate for the data gap. A comparison study of the root mean square (RMS) misfits of inversion outputs (with and without data gap filled) proves the effectiveness of the established relation. The inversion outputs obtained using the established relation brings out fault signatures in the data gap region. To examine the reliability and accuracy of these fault signatures, we occupy a portion of the data gap with new MT sites. We compare the inversion output from this new setup with the inversion output obtained from the established relation and observe that the electrical signatures in both outputs are spatially correlated. Further, a synthetic test on a similar earth model establishes the credibility and robustness of the derived relation.

Source and Origin of Roxana Silt and Middle Wisconsinan Midcontinent Glacial Activity

1989 ◽  
Vol 31 (3) ◽  
pp. 319-331 ◽  
Author(s):  
W. Hilton Johnson ◽  
Leon R. Follmer
Keyword(s):  
Mississippi River ◽  
Lake Michigan ◽  
Drainage System ◽  
River Valley ◽  
Upper Mississippi River ◽  
Upper Great Lakes ◽  
Mississippi River Valley ◽  
Depositional System ◽  
Stratigraphic Position ◽  
Late Wisconsinan

AbstractThick Roxana Silt (middle Wisconsinan) in central and southwestern Illinois traditionally has been interpreted as loess derived from valley-train deposits in the ancient Mississippi River valley. Winters et al. (H. A. Winters, J. J. Alford, and R. L. Rieck, Quaternary Research 29, 25–35, 1988) recently suggested that the Roxana was not directly related to glacial activity, but was derived from sediment produced by increased shoreline and spillway erosion associated with a fluctuating ancestral Lake Michigan. Because (1) paleoenvironmental and paleohydrologic conditions inferred in the hypothesis are unlikely for a loess depositional system and (2) loess did not accumulate during late Wisconsinan deglaciation under conditions similar to those hypothesized, we suggest the hypothesis should be rejected. Roxana distribution suggests the major source was drainage from the upper Mississippi River valley, and variations in loess thickness in Illinois can be explained by consideration of valley width, depth, orientation, and postdepositional erosion. Tills in the headwaters region of the ancient Mississippi drainage system in Minnesota and Wisconsin occur in the appropriate stratigraphic position and have colors and mineralogic compositions that suggest they could be the parent till of the Roxana. We believe a valley-train source for thick Roxana is most probable and urge continued consideration of middle Wisconsinan glaciation in the upper Great Lakes area.

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