Fault lines in southern ca

A fault system running nearly 70 miles along the coast of Los Angeles and Orange counties has the potential to trigger a magnitude 7.8 earthquake, according to a new study that is the latest to highlight the seismic threats facing Southern California. Known as the Palos Verdes fault zone, the system runs deep beneath the Palos Verdes Peninsula.

The Queen Charlotte-Fairweather fault extends 1,200 kilometers along southeastern Alaska and northern British Columbia, of which 900 kilometers lies offshore. During the past 120 years, the Queen Charlotte-Fairweather fault has generated six earthquakes of magnitude 7 or greater, including a magnitude 8.1 in 1949—Canada's largest recorded ...Detailed Description. Map of faults in southern California. Bold numbers show the average time between big earthquakes, determined at paleoseismic sites (triangles). Thick red lines show the extent of historic ruptures.Earthquake Fault Zones are delineated on U.S. Geological Survey topographic base maps at a scale of 1:24,000 (1 inch equals 2,000 feet). On older Earthquake Fault Zone maps, the zone boundaries are straight-line segments defined by turning points.Sep 23, 2021 ... Two maps of revised Earthquake Fault Zones have been prepared for the Rose Canyon Fault where it comes onshore on Coronado Island and ...The last time Southern California was struck by a quake as powerful as a magnitude 7.8 was in 1857, when the San Andreas fault ruptured from Monterey County through the San Gabriel Mountains north ...The April 2010 El Mayor-Cucapah earthquake revealed a previously undiscovered fault in the desert of Baja California, Mexico. Although the fault is relatively small, it produced a magnitude 7.2 earthquake. Scientists have become interested in smaller faults, because they are frequently the location of unexpectedly large earthquakes. Three types of geological hazards, referred to as seismic hazard zones, may be featured on the map: 1) liquefaction, 2) earthquake-induced landslides, and 3) overlapping liquefaction and earthquake-induced landslides. In addition, a fourth feature may be included representing areas not evaluated for liquefaction or earthquake-induced landslides.

This fault is one of the largest faults in the world, running more than 800 miles from the Salton Sea to Cape Mendocino. It carves the state in two. San Diego, Los Angeles and Big Sur are on the Pacific Plate. San Francisco, Sacramento and the Sierra Nevada are on the North American Plate. The two plates crisscross with dozens of active and ...The northeast- to east-striking Garlock fault of southern California is a major strike-slip fault with a left-lateral displacement of at least 48 to 64 km. It is also an important physiographic boundary since it separates along its length the Tehachapi-Sierra Nevada and Basin and Range provinces of pronounced topography to the north from the ...For faults in California and the rest of the United States (as well as the latest earthquakes) use the Latest Earthquakes Map: click on the "Basemaps and Overlays" icon in the upper right corner of the map. check the box for "U.S. Faults". mouse-over each fault to get a pop-up window with the name of the fault.1:100,000, fault could be more discontinuous than continuous and mapping is accurate at <50,000 scale. 1:250,000, fault location may be inferred or is poorly constrained. Click on the fault lines for more information. Note* The earthquake faults are color coded by unique name and section not type. Data source: USGS.A map of the Texas fault lines shows where the most and least risk areas in the state are located. The Earthquake Hazards Program, part of the U.S. Geological Survey, shows the fau...The most famous example is California's San Andreas Fault, which stretches some 600 miles (1,000 kilometers) from southern California to north of San Francisco. The sideways motion of the fault's ...San Clemente Fault Zone. TYPE OF FAULTING: right-lateral and vertical offsets. LENGTH: at least 210 km; essentially continuous with the San Isidro fault zone, off the coast of Mexico. NEARBY COMMUNITY: San Diego (70 km offshore); forms scarp on east side of San Clemente Island. MOST RECENT SURFACE RUPTURE: Holocene. SLIP RATE: roughly 1.5 mm/yr.

Brian Snyder/Reuters. New York CNN —. College campuses across the United States have erupted with pro-Palestinian protests, and school administrators are …The boundary between these two giant plates is the Queen Charlotte fault - Canada's equivalent of the San Andreas fault. Canada's largest historical earthquake- a magnitude 8.1, occurred along this fault on August 22, 1949. This earthquake, larger than the 1906 San Francisco earthquake, caused nearly a 500-km-long segment of the Queen …• Pleito Fault (Grapevine - Interstate 5, Wheeler Ridge) • Raymond Hill Fault (San Marino, Arcadia, South Pasadena) • Redondo Canyon Fault (Palos Verdes Estates, Redondo Beach) • Rinconada Fault (Paso Robles, Santa Margarita) • San Andreas Fault (Parkfield, Frazier Park, Palmdale, Wrightwood, San Bernardino, Banning, Indio)California won't fall into the ocean, but it could get nudged hundreds of miles offshore, making Nevada the new coastline of the continent, scientists at the University of Nevada, Reno hypothesize.Figure 4.45. Map showing the detail of many of the faults in Southern California. The width of the color-shaded areas of the different faults shows the general angle that these earthquake faults descend into the crust. Vertical fault are narrow lines, whereas low-angle thrust faults are wider.

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U.S. Geological Survey, Coastal and Marine Geology Program c/o Stephen R. Hartwell 400 Natural Bridges Drive Santa Cruz, CA 95060-5792 US. 831-460-7814 (voice) 831-427-4748 (FAX) [email protected] models for the A.D. 1812 and 1857 earthquakes through Cajon Pass (California, USA). (A) Preferred slip model for the 1812 event. Right-lateral slip imposed on the San Jacinto fault (SJF) and ...The April 2010 El Mayor-Cucapah earthquake revealed a previously undiscovered fault in the desert of Baja California, Mexico. Although the fault is relatively small, it produced a magnitude 7.2 earthquake. Scientists have become interested in smaller faults, because they are frequently the location of unexpectedly large earthquakes. Below is a map of Southern California to display significant earthquakes and faults. The fault traces are shown in red. This is an interactive map. To toggle detailed instructions on how to use the map and its associated control panel, click the informtation button ("i") to the right. A link to the glossary can also be found there.

The California Geological Survey's interactive geological map allows users to identify the different rock types and fault lines throughout California. In addition to the web viewer, the GIS data can be downloaded for further use. Click here to use the California geological interactive map. Source: California Geological Survey. 1 of 8.Feb 8, 2024 ... During the lecture I noticed one or two of the fault lines that runs perpendicular to where the fault line bends near Southern California.Joint earthquake ruptures of the San Andreas and San Jacinto faults, California, USA. Geology, 2021; DOI: 10.1130/G49415.1; ... from the southern San Andreas Fault through the Imperial ... Owing to wiggles in the fault line, portions of the thin red lines can be more than 100 ft from the fault. By presenting the San Andreas Fault map as interactive web-based imagery, anyone can pinpoint the fault anywhere along its trace. And by using a thin red line, the underlying landscape features are minimally obscured. The California Geological Survey's interactive map allows users to identify the location and classification of faults throughout California. Information available includes the age of the most recent activity on each fault segment, surface rupture areas, and whether or not the faults are visible at the surface. Click here to use the California fault activity map. Southern California. Four EDM networks located in Southern California show strain accumulation on the San Andreas fault system in this region. This map shows the locations of 4 two-color EDM (Electronic Distance Meter) networks in Southern California. These networks are radial with approximately 12 baselines using a common, central station. The San Andreas fault is one of the most famous and—because of its proximity to large population centers in California—one of the most dangerous earthquake-generating faults on Earth. Concern about the timing, magnitude, and location of future earthquakes, combined with convenient access, have motivated more research on this fault than on any other. In recent years, an increasing number of ...large faults in California and Nevada faults cut the Earth's crust. (data compiled by The largest historical earthquakes Jerry P. Eaton, USGS, that occurred along the San and others) Andreas fault were those in 1857 and 1906 (see the map on page 4 ). The earthquake of January 9, 1857, in southern California ap-parently was about the same mag-In “Earthquake Country,” California’s three major fault lines—the San Andreas, the Hayward and San Jacinto—have experienced an unusually calm century of inactivity, a new study shows. Of ...This study shows that there are seven active fault lines Southern Davao Region namely Dacudao Fault with a magnitude of 6.5Mw, Lacson Fault with a magnitude of 6.8Mw, Tamugan Fault with a ...Fault, an active dextral strike-slip fault in Trinidad's western offshore. van Andel and Sachs (1964) were the first to map an active fault that cuts Holocene sediment and the seafloor in this ...TYPE OF FAULT: reverse. LENGTH: 34 km; has several parallel strands. NEAREST COMMUNITIES: Malibu, Pacific Palisades. MOST RECENT SURFACE RUPTURE: Holocene, in part; otherwise Late Quaternary. SLIP RATE: roughly 0.3 mm/yr. INTERVAL BETWEEN MAJOR RUPTURES: uncertain. OTHER NOTES: This is a north-dipping fault.

NEAREST COMMUNITIES: Laguna Beach, Dana Point, Oceanside, Encinitas. MOST RECENT MAJOR RUPTURE: Holocene, in part; mostly Quaternary. SLIP RATE: estimated at between 0.8 and 2.1 mm/yr. INTERVAL BETWEEN MAJOR RUPTURES: uncertain. PROBABLE MAGNITUDES: M W 6.0 - 7.2 (?); uncertain due to uncertainty in the continuity of the fault zone.

Mar 7, 2017 ... New study finds rupture of Newport-Inglewood/Rose Canyon fault is possible, affecting coast from San Diego to Los Angeles.Visit the San Andreas Fault. Parkfield bridge, Palmdale road cut, Wallace Creek and the SAF in Highland, CA. Visiting the fault is easy. All it takes is a decent car. No 4WD is necessary unless you want to get to a few difficult places, and most of these are just a short hike from a public road. In some places like the Morongo Indian ...The Los Angeles Times says the map allows users to input. Fault lines in southern california map. But new analysis exhibits that a a lot less very well-identified fault, functioning underneath the heart from the East Bay, poses a better Hazard. Because it's been in excess of one hundred forty four a long time since the very last major ...GOLDEN, Colo. - Nearly 75 percent of the U.S. could experience damaging earthquake shaking, according to a recent U.S. Geological Survey-led team of 50+ scientists and engineers. This was one of several key findings from the latest USGS National Seismic Hazard Model (NSHM). The model was used to create a color-coded map that pinpoints where damaging earthquakes are most likely to occur based ...This overview map above shows the location of the MASTER flight lines for the Southern California Faults (SCF) project. It links to a larger version of the overview map. Most faults have both daytime and nighttime MASTER data pairs. Daytime flightlines are represented by solid lines, nighttime flightlines by dashed lines; lines are offset from ...Detailed Description. Shaded relief map of the Mojave Desert Region, made by draping 1 arc second SRTM elevation data over a hillside of the same topography. Light blue lines show faults of the USGS Quaternary fault database. Dark blue lines show faults identified and described in 1:100k scale geologic mapping completed by previous project efforts.Some recent Arizona earthquakes. 1887 Sonoran Earthquake – A M7.6 earthquake on the Pitaycachi fault near the Arizona -Mexico border, south of Douglas killed nearly 60 people and was felt widely throughout the Southwest, including: Tucson, Bisbee, Yuma, Phoenix, Prescott, Albuquerque, El Paso, and Sonora, Mexico.The northeast- to east-striking Garlock fault of southern California is a major strike-slip fault with a left-lateral displacement of at least 48 to 64 km. It is also an important physiographic boundary since it separates along its length the Tehachapi-Sierra Nevada and Basin and Range provinces of pronounced topography to the north from the ...Cucamonga Fault Zone. TYPE OF FAULT: thrust. LENGTH: about 30 km. NEARBY COMMUNITIES: Claremont, Upland, Cucamonga. SLIP RATE: between 5 and 14 mm/yr. INTERVAL BETWEEN MAJOR RUPTURES: estimated at roughly 600-700 years. PROBABLE MAGNITUDES: M W 6.0 - 7.0. MOST RECENT RUPTURE: very recent Holocene.In California, the San Andreas Fault is the plate boundary, running east of Los Angeles and west of San Francisco, but in actuality the plate boundary is diffuse and spreads as far east as Salt Lake City, Utah as part of the Basin and Range. To the south, the San Andreas blends into a series of faults, like the San Jacinto Fault, and it ...

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Urban areas in Southern California are at risk from major earthquakes, not only quakes generated by long-recognized onshore faults but also ones that occur along poorly understood offshore faults. We summarize recent research findings concerning these lesser known faults. Research by the U.S. Geological Survey during the past five years indicates that these faults from the eastern Santa Barbara ChThe genesis of this law was the 1971 Silmar earthquake in Southern California, "where a veterans hospital was right on top of a fault," agency spokesman Don Drysdale said.Owing to wiggles in the fault line, portions of the thin red lines can be more than 100 ft from the fault. By presenting the San Andreas Fault map as interactive web-based imagery, anyone can pinpoint the fault anywhere along its trace. And by using a thin red line, the underlying landscape features are minimally obscured.1:100,000, fault could be more discontinuous than continuous and mapping is accurate at <50,000 scale. 1:250,000, fault location may be inferred or is poorly constrained. Click on the fault lines for more information. Note* The earthquake faults are color coded by unique name and section not type. Data source: USGS.The Inner California Borderland (ICB) records a middle Oligocene transition from subduction to microplate capture along the southern California and Baja coast. The closest nearshore fault system, the Newport-Inglewood/Rose Canyon (NIRC) fault complex is a dextral strike-slip system that extends primarily offshore approximately 120 km from San Diego to Newport Beach, California. Holocene slip ...The 2010 Geologic Map of California and the Fault Activity Map of California were prepared in recognition of the California Geological Survey’s 150th Anniversary. Both are all-digital products built on the original compilations of C.W. Jennings published in 1977 and 1994. The digital version of the Jennings (1977) geologic map was released in ...The Great Southern California ShakeOut earthquake drill is based on a magnitude 7.8 scenario earthquake on the San Andreas fault in southern California. This portion of the San Andreas fault has been identified as the most likely source of a very large earthquake in California (Working Group on California Earthquake Probabilities).As part of the earthquake drill, computer simulations of the ...For decades the Geologic Atlas of California (discussed in the next section) has been the primary source of regional-scale geologic maps in California. In an effort to keep the maps current, the CGS has been compiling a new series of Regional Geologic Maps (RGM), starting in 1981. The new maps cover the same areas as the older Geologic Atlas of ...This region of the United States has been tectonically active since the supercontinent Pangea broke up roughly 200 million years ago, and in large part because it is close to the western boundary of the North American plate. Since the formation of the San Andreas Fault system 25-30 million years ago, the juxtaposition of the Pacific and North … ….

1:100,000, fault could be more discontinuous than continuous and mapping is accurate at <50,000 scale. 1:250,000, fault location may be inferred or is poorly constrained. Click on the fault lines for more information. Note* The earthquake faults are color coded by unique name and section not type. Data source: USGS.NASCAR cheating is a tricky subject. Some cases mean blatant cheating, and some the lines are blurred. Learn more about NASCAR cheating. Advertisement ­With the advent of the autom...The various colors and line types indicate different ages of the most recent earthquakes on the fault and how well the location of the fault is constrained. For more details, see Quaternary Faults.Map showing Quaternary faults in the western U.S. and Pacific Ocean. Note that most faults that can affect residents are either onshore or just offshore.L. Grant Ludwig, J. N. Brune, Precariously balanced rocks in the western San Bernardino Mountains and the 1812 earthquake on the San Andreas-San Jacinto fault, paper presented at the 20th Annual Meeting of the Southern California Earthquake Center, Palm Springs, CA, 11 to 15 September 2010. Google Scholar. 28.This geologic map database is comprised of new geologic mapping, at a 1:24,000 scale, along the southern Bartlett Springs fault in the northern California Coast Ranges. The map covers an area of 258 square miles in Lake, Napa, Colusa, and Yolo counties, work was undertaken between 2016 and 2021, and supported by the USGS National Cooperative ...Hundreds of active faults run through California. With hundreds of known faults running through the state, California is no stranger to earthquakes. In fact, one occurs about every three minutes, though the majority of these are too small to be felt. But even with all this seismic activity, the state's three major fault lines have remained ...The 2010 Geologic Map of California and the Fault Activity Map of California were prepared in recognition of the California Geological Survey’s 150th Anniversary. Both are all-digital products built on the original compilations of C.W. Jennings published in 1977 and 1994. The digital version of the Jennings (1977) geologic map was released in ...A hypothetical 7.8-magnitude quake epicentered on the San Andreas Fault near the Salton Sea would be felt throughout LA, and damage would be widespread. But the strongest shaking would be felt 30 ...Significant Southern California Quakes and Faults. Chronological Earthquake Index. Earthquake Catalogs - searchable catalog of events recorded by SCSN. SCSN Daily and Weekly Earthquake Summary. SCSN Interactive Weekly Earthquake Plots. SCSN Earthquake Commentary Archive. SCSN Special Earthquake Reports. Seismicity Map (1932-1996) TYPE OF FAULTING: primarily right-lateral strike-slip. LENGTH: roughly 140 km. NEARBY COMMUNITIES: Castaic, Saugus, Sunland. MOST RECENT SURFACE RUPTURE: Late Quaternary west of intersection with the Sierra Madre fault zone; Quaternary east of that intersection; Holocene only between Saugus and Castaic. SLIP RATE: 1 mm/yr to 5 mm/yr. Fault lines in southern ca, Faults of Southern California. Mojave Region. This map covers most of the region known as the Mojave Block. Though most fault types can be found here, this region is dominated by northwest-trending, right-lateral strike-slip faults, the densest cluster (centered roughly at Barstow) of which is often known as the Eastern California Shear Zone ..., A hypothetical 7.8-magnitude quake epicentered on the San Andreas Fault near the Salton Sea would be felt throughout LA, and damage would be widespread. But the strongest shaking would be felt 30 ..., San Andreas Fault Homepage. Latest news: earthquakes, volcanic eruptions, tsunamis and San Andreas fault. For more information, click on the following phrases for a Google search: San Andreas fault map, San Andreas fault line, San Andreas fault pictures, San Andreas fault facts, San Andreas fault earthquake prediction, San Andreas fault zone., The 2010 Geologic Map of California and the Fault Activity Map of California were prepared in recognition of the California Geological Survey's 150th Anniversary. Both are all-digital products built on the original compilations of C.W. Jennings published in 1977 and 1994. The digital version of the Jennings (1977) geologic map was released in ..., Hill (1928 #4959) first mapped the fault and named it the Pinto Mountain fault. Later workers have referred to the fault variously as the Pinto fault (Miller, 1938 #6684), the Warrens Well fault (Hill and Dibblee, 1953 #923), and the Base Line fault (Hewett, 1955 #6681). Allen (1957 #4787) first recognized that a branch of the Pinto Mountain ..., However, in the new study, the estimate for the likelihood that California will experience a magnitude 8 or larger earthquake in the next 30 years has increased from about 4.7% for UCERF2 to about 7.0% for UCERF3. "The new likelihoods are due to the inclusion of possible multi-fault ruptures, where earthquakes are no longer confined to ..., County of San Diego: Earthquake Facts and Preparedness County of San Diego Office of Emergency Services. Designed for the original ShakeOut in 2008, the ShakeOut Scenario is a detailed picture of a possible magnitude 7.8 earthquake along the southern San Andreas fault. The Scenario is also the basis of the 2009 ShakeOut activities in Southern California, as much more can still be learned in ..., Download scientific diagram | Map of the Ventura region and Ventura Fault in Southern California; red lines show regional faults, with teeth on the hanging wall side. AA 0 shows cross section ..., Current Earthquake Information. Fault trace visible as a line of trees above the orange grove east of Hemet, CA along State 74. While most of the major fault lines have some surface expression here, there are many that do not. These faults can also produce large earthquakes, such as the M6.7 Reseda/Northridge Earthquake of January 17, 1994., The last time one of these maps was released in the city was in 2003. Earthquake fault line in california map. But new study exhibits that a a lot less effectively-acknowledged fault, working underneath the heart from the East Bay, poses a larger Risk. This type of plausible quake might be strong adequate to trigger liquefaction in all Bay Area ..., Introduction. Group C of the Southern California Earthquake Center was charged with an evaluation of earthquake fault sources in the Los Angeles Basin and nearby urbanized areas based on fault geology. The objective was to determine the location of active faults and their slip rates and earthquake recurrence intervals., Enjoy your walk on the mesa; take in the sweeping views knowing that 3+ miles directly beneath your feet is the San Andreas fault. After hiking 1.6 km, the Horseshoe Palm grove appears on the right-hand side of the trail at the base of the hill. This long string of palm trees extends over 1.5 km. , Fault Activity Map of California (2010) To provide information for those concerned with land use on or near geologic faults in California., Interactive map of fault activity in California. The California Geological Survey's interactive map allows users to identify the location and classification of faults throughout California. Information available …, The Newport-Inglewood fault zone is what was responsible for destroying Long Beach in 1933. The California Geological Survey considers it "a very dangerous fault.". It's moved at some point ..., Jul 9, 2019 ... The San Andreas and Hayward fault lines are long. Hayward is 74 miles and San Andreas is 800 miles — or half the length of California., The best way to see California's earthquake faults is to go to HBO Max and stream "San Andreas," a 2015 action movie starring the Rock and Paul Giamatti that holds up surprisingly well. No ..., Apr 25, 2023 ... 0+ quakes striking southern California. For Riverside County and the Temecula area, our most notable faults are the San Andreas and San Jacinto., For faults in California and the rest of the United States (as well as the latest earthquakes) use the Latest Earthquakes Map: click on the "Basemaps and Overlays" icon in the upper right corner of the map. check the box for "U.S. Faults". mouse-over each fault to get a pop-up window with the name of the fault. , Earthquakes. The San Andreas Fault might be California's most known fault line, but maybe not its most destructive. Recently, many faults have been discovered in the Sierra and Southern Cascades ..., The Newport-Inglewood fault zone is what was responsible for destroying Long Beach in 1933. The California Geological Survey considers it "a very dangerous fault.". It's moved at some point ..., This geologic map database is comprised of new geologic mapping, at a 1:24,000 scale, along the southern Bartlett Springs fault in the northern California Coast Ranges. The map covers an area of 258 square miles in Lake, Napa, Colusa, and Yolo counties, work was undertaken between 2016 and 2021, and supported by the USGS National Cooperative ..., These maximum rates for the MCF are comparable to the present-day geodetic slip rate for the southern San Andreas Fault (~23 mm yr −1) 22,40,41,42,43 and suggest that the MCF, once the principal ..., The southern San Andreas Fault from Parkfield to the Salton Sea in southern California is considered by seismologists as a prime threat for a major earthquake (exceeding magnitude 7) in the near future. The fault marks the boundary of two massive blocks of the earth's crust called tectonic plates: the Pacific plate to the west and the North ..., Slip models for the A.D. 1812 and 1857 earthquakes through Cajon Pass (California, USA). (A) Preferred slip model for the 1812 event. Right-lateral slip imposed on the San Jacinto fault (SJF) and ..., Geology. The Imperial Fault Zone is a right lateral-moving strike-slip fault, representing the northernmost transform fault associated with the East Pacific Rise. It is connected to the San Andreas Fault by the Brawley Seismic Zone. It terminates on its southern end at the Cerro Prieto spreading center., Lost Lake is the small pond in the center of the picture. The GoogleEarth image below shows the fault relations at Lost Lake, including a very nice example of an offset stream. The San Andreas is a right lateral fault, meaning that an object across the fault from the observer is moving to the right (note the arrows in the picture at the bottom)., In Southern California, plate boundary motion between the North American and Pacific plates is distributed across several sub-parallel fault systems. The offshore faults of the California Continental Borderland (CCB) are thought to accommodate ∼10-15% of the total plate boundary motion, but the exact distribution of slip and the mechanics of slip partitioning remain uncertain., Plotted for reference on the background are the surface traces of the major faults in the area (shown as light blue-green lines -- the most prominent being the San Andreas …, The California Geological Survey, a division within the California Department of Conservation, provides data and analysis of California's seismic and geologic hazards. These hazards include earth shaking (strong motion), fault ruptures, landslides, liquefaction, and tsunamis as well as mineral hazards such as radon, mercury, and asbestos. , Discover, analyze and download data from California State Geoportal. Download in CSV, KML, Zip, GeoJSON, GeoTIFF or PNG. Find API links for GeoServices, WMS, and WFS. Analyze with charts and thematic maps. Take the next step and create StoryMaps and Web Maps., Ground shaking is the most powerful predictor of damage from an earthquake. The U.S. Geological Survey (USGS) National Seismic Hazard Map shows the strength of ground shaking that has a 1 in 50 chance of being exceeded in a particular place in the lower 48 states over a period of 50 years. These maps are used in determining building seismic …, New Madrid Seismic Zone. The New Madrid Seismic Zone (NMSZ) ( / ˈmædrɪd / ), sometimes called the New Madrid Fault Line, is a major seismic zone and a prolific source of intraplate earthquakes (earthquakes within a tectonic plate) in the Southern and Midwestern United States, stretching to the southwest from New Madrid, Missouri .