Serpentine, which happens to be CA’s state rock, consists of a group of soft, slippery minerals which allow the crust in this region to slide continuously without the buildup and release of pressure associated with more brittle, stickier rocks. It ends abruptly where it connects to another plate boundary, either another transform, a spreading ridge, or a subduction zone. It ends abruptly and is connected to another transform, a spreading ridge, or a subduction zone. Other geomorphic features that accompany terrestrial transform boundaries are linear fault valleys and offset streams. Th us the fault length-ens over time (Fig. The majority of the syncline is found in Southland and The Catlins in the island's southeast, but a smaller section is also present in the Tasman District in the island's northwest. 8.1g). At this point it splits into a set of smaller faults known as the Marlborough Fault System. A transform fault or transform boundary is a fault along a plate boundary where the motion is predominantly horizontal. Transform Plate Boundaries - Transform Fault. It’s the "on-land" boundary of the Pacific and Australian Plates. This lateral movement of seafloors past each other is where transform faults are currently active. The Mechanics of the Earthquake. This is due to the plates moving parallel with each other and no new lithosphere is being created to change that length. In the plot above the area of the circles correlates with the area percentage of samples occupied by the grain size. Motion on the Alpine fault is not completely strike-slip.  This evidence helps to prove that new seafloor is being created at the mid-oceanic ridges and further supports the theory of plate tectonics.  During this period, the Farallon plate, followed by the Pacific plate, collided into the North American plate. Most such faults are found in oceanic crust, where they accommodate the lateral offset between segments of divergent boundaries, forming a zigzag pattern. A paper written by geophysicist Taras Gerya theorizes that the creation of the transform faults between the ridges of the mid-oceanic ridge is attributed to rotated and stretched sections of the mid-oceanic ridge. Transform Plate Boundaries are locations where two plates slide past one another. ... continental Transform Margins Boundary Two plates sliding past each other; University of British Columbia; EOSC 314 - Fall 2012. Fracture zones represent the previously active transform-fault lines, which have since passed the active transform zone and are being pushed toward the continents. The Alpine Fault is a geological fault, known as a right-lateral strike-slip fault, that runs almost the entire length of New Zealand's South Island. These spreading ridges are often connected by transform faults in large part because magma coming toward the surface is 1) not always coming up in a perfectly straight line; 2) not always surfacing at the same time and 3) not always occurring at the same rate. This is a result of oblique seafloor spreading where the direction of motion is not perpendicular to the trend of the overall divergent boundary. Transform faults specifically relieve the strain by transferring displacement between ridges or subduction zones. Since … Another example of a transform boundary on land is the Alpine Fault of New Zealand. Research. 3. These elevated ridges on the ocean floor can be traced for hundreds of miles and in some cases even from one continent across an ocean to the other continent.  This occurs over a long period of time with the spreading center or ridge slowly deforming from a straight line to a curved line. Streams that run across transform or strike-slip faults may slowly get offset over time as the fault moves and slips as shown in the images below. It is a plate boundary where one plate slides past one another.  It ends abruptly where it connects to another plate boundary, either another transform, a spreading ridge, or a subduction zone.. As shown below, a person standing on one side of a right-lateral strike-slip fault will watch a tree on the opposite side move right as the fault slips. This is unlike the North Island boundary, where a subduction zone is under water off the east coast. As shown in the map below, they are particularly common along divergent plate boundaries where they connect sections of oceanic spreading centers or mid-ocean ridges, helping create some of the longest topographic features on the planet. The Alpine Fault occurs at a transform boundary. Although predominantly associated with subduction zones, tremor also occurs along the deep extension of the strike-slip San Andreas Fault. The San Andreas connects a divergent boundary in the Gulf of California with the Cascadia subduction zone. It includes an oceanic transform (the Macquarie Ridge), two oppositely verging subduction zones (Puysegur and Hikurangi), and a transpressive continental transform, the Alpine Fault through South Island, New Zealand. The San Andreas connects a divergent boundary in the Gulf of California with the Cascadia subduction zone. In the middle the Alpine Fault is a transform boundary and has both dextral (right-lateral) strike-slip movement and uplift on the southeastern side. The San Andreas fault of California is a prime example of a continental transform boundary; others are the North Anatolian fault of northern Turkey, the Alpine fault crossing New Zealand, the Dead Sea rift in the Middle East, the Queen Charlotte Islands fault off western Canada, and the Magellanes-Fagnano fault system of South America. Friction-generated melt (pseudotachylyte) ^ Top of page. 100% (1/1) Fairweather Fault Queen Charlotte-Fairweather Fault System. 213 pages. Now, think about it for a second. A transform fault is a special case of a strike-slip fault that also forms a plate boundary. Finally, transform faults form a tectonic plate boundary, while transcurrent faults do not. Stress levels on the Alpine fault. Similarly, if the same situation occurred and the fault was left-lateral, the tree would move left.  Finally, when two upper subduction plates are linked there is no change in length. The best example is the San Andreas Fault on the Pacific coast of the United States. This fault has ruptured four times in the past 900 years, each time producing an earthquake of about magnitude 8. In the middle the Alpine Fault is a transform boundary and has both dextral (right-lateral) strike-slip movement and uplift on the southeastern side. All Right Reserved. Mechanism of earthquakes and nature of faulting on the mid-oceanic ridges, Journal of Geophysical Research, 72, 5–27. At transform boundaries lithosphere is neither created nor destroyed. What type of earthquakes occur at transform boundaries? Like all plate boundaries, the movement of crust along transform and strike-slip faults creates earthquakes. transform boundary between the Pacific and Australian plates. The Alpine Fault, which runs for about 600km up the spine of the South Island, is one of the world’s major geological features. …plates and is called a ridge–ridge transform fault. Unlike divergent (constructive) and convergent (destructive) plate boundaries, lithosphere at transform boundaries is neither created nor destroyed deeming them “conservative” plate boundaries. With new seafloor being pushed and pulled out, the older seafloor slowly slides away from the mid-oceanic ridges toward the continents. These occur when two descending subduction plates are linked by a transform fault. Real world examples of Boundaries include: Transform: Alpine Fault of New Zealand Convergent: Oceanic-Continental:Andes Mountains Divergent: Oceanic-Oceanic Mid-Atlantic Ridge Divergent: Continental-Continental: East African Rift Valley Transform: Alpine Fault of New Zealand Convergent: Continental-Continental: Himalayan Mountains: Convergent: Oceanic-Oceanic: Marianas … Differential movement and earthquakes do not occur beyond an offset because the seafloor areas on both sides of the fracture zone in such localities are parts… Reid, H.F., (1910). A transform fault or transform boundary is a fault along a plate boundary where the motion is predominantly horizontal.  The formation of the San Andreas Fault system occurred fairly recently during the Oligocene Period between 34 million and 24 million years ago. Fractures, normal faults and cracks in the basin also allow water to come up from the underneath the surface forming springs. Collectively, oblique convergence across Marlborough, along with the translation of crust onto the underlying pacific slab results in uplift of the Kaikoura mountains and marine terraces along the coast. Since the Alpine fault lies at slight angle to the plate motion vector and is dipping to the southeast, some convergence occurs across the fault and uplifts the Southern Alps mountains, including Mt. Queen Charlotte Fault. Earthquakes along the fault, and the associated earth movements, have formed the Southern Alps. 22 Agenda Transform plate boundary o Examples of Oceanic Fracture Zones Romanche Fracture Zone Clipperton Fracture Zone Transform Fault Zones in Ophiolites Processes at transform plate boundaries o Contraction and Extension in Transform Fault Systems. Tectonic tremor is characterized by persistent, low-frequency seismic energy seen at major plate boundaries. in The California Earthquake of April 18, 1906, Report of the State Earthquake Investigation Commission, Carnegie Institution of Washington, Washington D.C. Sykes, L.R. These rocks are created deep inside the Earth's mantle and then rapidly exhumed to the surface. I’ve analyzed quartz grain size data from ~250 rocks spanning 170 km of the fault. … They form the most prominent and widespread fracture system on Earth. It occurs between the Pacific Plate... See full answer below. Wilson described six types of transform faults: Growing length: In situations where a transform fault links a spreading center and the upper block of a subduction zone or where two upper blocks of subduction zones are linked, the transform fault itself will grow in length.. As shown below, a right bend in a right-lateral strike slip fault (or a left bend in a left lateral strike slip fault) is called a releasing bend and results in extension which in turn can form normal faults and pull-apart basins. Other locations include: the East Pacific Ridge located in the South Eastern Pacific Ocean, which meets up with San Andreas Fault to the North. Transform boundaries are also known as conservative plate boundaries because they involve no addition or loss of lithosphere at the Earth's surface. @2018 - scienceterms.net. Moving into southern CA, a slight right bend in the fault creates a pull apart basin allowing for the opening of the Salton Sea. New Zealand Marlborough Fault System Hope Fault Haast Schist Strike-slip tectonics. Instead, due to the relative motion of the plates being parallel to and in opposite directions across the fault, the plates slide past each other laterally. While restraining bends can form high mountains, releasing bends create low points on the landscape where sediment and water from rivers and oceans can flow in. These mid-oceanic ridges are where new seafloor is constantly created through the upwelling of new basaltic magma. Starting in the Gulf of California, the San Andreas picks up where the East Pacific Rise spreading center leaves off. On the South Island, this has resulted in the right lateral, oblique, Alpine fault. The differential movement along a transform fault agrees with the fault motions determined by seismic analyses. EOSC 314 Lec 7_Plate_Tectonics_and sediment_Fall 2012_MSL_Final. What is another name for a transform boundary? The Alpine Fault then runs the length of the South Island just west of the Southern Alps to near Lewis Pass in the central northern section of the island. It includes an oceanic transform (the Macquarie Ridge), two oppositely verging subduction zones (Puysegur and Hikurangi), and a transpressive continental transform, the Alpine Fault through South Island, New Zealand. The Alpine Fault. 1. Transform faults are closely related to transcurrent faults and are commonly confused. In his work on transform-fault systems, geologist Tuzo Wilson said that transform faults must be connected to other faults or tectonic-plate boundaries on both ends; because of that requirement, transform faults can grow in length, keep a constant length, or decrease in length. The transform fault is simply a strike-slip fault as the plates move, the crust is fractured and … Transform boundaries occur where the Earth’s tectonic plates slide past each other horizontally along transform or strike-slip faults. A transform fault or transform boundary is a plate boundary where the motion is predominantly horizontal. This movement is described based on the perspective of an observer standing on one of the plates, looking across the boundary at the opposing plate.  The collision led to the subduction of the Farallon plate underneath the North American plate. Overtime, this weakness provides easily erodible material for rivers and wind to transport away creating huge scratch like features on the Earth’s surface. The data were collected “blindly” with no judgements regarding the recrystallized state (e.g. In particular, bends along strike-slip faults can form both basins and mountains. Known as the St. Paul, Romanche, Chain, and Ascension fracture zones, these areas have deep, easily identifiable transform faults and ridges. In the case of ridge-to-ridge transforms, the constancy is caused by the continuous growth by both ridges outward, canceling any change in length. Sadly, destruction from this quake created fires that burned many buildings in San Francisco and killed hundreds to thousands of people. Photo credit: Steven Smith. Transform faults are commonly found linking segments of divergent boundaries (mid-oceanic ridges or spreading centres). en The continent of Zealandia, which separated from Australia 85 million years ago and stretches from New Caledonia in the north to New Zealand’s subantarctic islands in the south, is now being torn apart along the transform boundary marked by the Alpine Fault. Unlike southern CA, the central portion of the San Andreas does not experience many earthquakes in large part due to the presence of serpentine minerals in the rocks beneath the surface. Both types of fault are strike-slip or side-to-side in movement; nevertheless, transform faults always end at a junction with another plate boundary, while transcurrent faults may die out without a junction with another fault. They run across the ocean floor for thousands of kilometers, imparting a spectacular fabric to the solid surface of our planet. Photo credit: Steven Smith. That leaves the third type which we refer to as a transform plate boundary. Decreasing length faults: In rare cases, transform faults can shrink in length. peridotite and gabbro rocks were discovered in the edges of the transform ridges. Drop off near the Olivine wilderness area, Fiordland Photo credit: Steven Smith In the region of New Zealand, the 3000 km long Australia-Pacific plate boundary extends from south of Macquarie Island to the southern Kermadec Island chain. Before heading offshore to its termination at the Mendocino triple junction, the San Andreas makes a stop in San Francisco where it shook the city violently in the 1906, magnitude 7.9, San Francisco Earthquake. The Alpine Fault from space. "Dynamical Instability Produces Transform Faults at Mid-Ocean Ridges", 10.1130/0016-7606(1970)81[3513:ioptft]2.0.co;2, Deep-ocean Assessment and Reporting of Tsunamis, North West Shelf Operational Oceanographic System, Jason-2 (Ocean Surface Topography Mission), https://en.wikipedia.org/w/index.php?title=Transform_fault&oldid=989741808, Articles with unsourced statements from February 2020, All articles with specifically marked weasel-worded phrases, Articles with specifically marked weasel-worded phrases from November 2017, Creative Commons Attribution-ShareAlike License, International Tectonic Dictionary – AAPG Memoir 7, 1967, The Encyclopedia of Structural Geology and Plate Tectonics – Ed. Transform boundaries also form on larger scales on land like the San Andreas fault in Western North America and the Alpine fault in New Zealand. As mentioned above, fault geometry plays a big role in forming topography along transform boundaries. Active transform faults are between two tectonic structures or faults. GEOL430 students after a field trip to see the Alpine Fault. California's San Andreas fault is a transform boundary. This set of faults, which includes the Wairau Fault, the H… Constant length: In other cases, transform faults will remain at a constant length. Transform boundaries are places where plates slide sideways past each other. Transform faults are not limited to oceanic crust and spreading centers; many of them are on continental margins. o Thermal Structure and the “Cold Wall.” o Ridge Offset and Spreading Rate Continental transform faults o Examples of … Once the spreading center separating the Pacific and the Farallon plates was subducted beneath the North American plate, the San Andreas Continental Transform-Fault system was created.. 2. Although separated only by tens of kilometers, this separation between segments of the ridges causes portions of the seafloor to push past each other in opposing directions. While the east coast Hikurangi subduction zone accommodates a large portion of the plate convergence, the inland North Island fault strike-slip fault system accommodates the lateral motion between the plates. Satellite image of the South Island of New Zealand, showing the Alpine Fault. Thanks to oblique convergence between the Pacific and Australian plates, New Zealand is home to several kinds of transform boundaries. It forms a transform boundary between the Pacific Plate and the Indo-Australian Plate. As this takes place, the fault changes from a normal fault with extensional stress to a strike-slip fault with lateral stress. Another example of a transform boundary on land is the Alpine Fault of New Zealand. In this entry, the emphasis is on the oceanic transform faults, … Linear fault valleys can form along strike-slip and transform faults as rocks get ground up during movement and slipping. The opposite occurs when a ridge linked to a subducting plate, where all the lithosphere (new seafloor) being created by the ridge is subducted, or swallowed up, by the subduction zone. (1967). On the North Island, oblique convergence between the plates has resulted in not one kind of fault but two. What is another name for a left bend in a left lateral strike-slip fault? Transform boundaries are therefore defined by a vertical fault on which slips parallel to the Earth’s surface. In the South Island of New Zealand, the boundary between the Australian and Pacific tectonic plates can be seen on land. The most prominent examples of the mid-oceanic ridge transform zones are in the Atlantic Ocean between South America and Africa. They also act as the plane of weakness, which may result in splitting in rift zones. Mountains, basins and unique topography can form along transform boundaries depending on the fault’s geometry, the rock type and how parallel the motion of the plates are to the strike of the fault. 8.11). The uplift is due to an element of convergence between the plates, meaning that the fault has a significant high-angle reverse oblique component to its displacement. Below we’ll describe some of these features in more detail and take a look at some examples of transform boundaries from different locations around the world. Here we present the observations of tectonic tremor along New Zealand's Alpine Fault, a major transform boundary that is late in its earthquake …  These length changes are dependent on which type of fault or tectonic structure connect with the transform fault. ... such as the San Andreas Fault system in California, the North Anatolian Fault system in northern Turkey, the Alpine Fault in New Zealand, and the Altyn Tagh Fault in northern Tibetan Plateau, constitute veritable keirogens. A bend can be “right” or “left” depending on which way the fault turns if you were walking along strike. This steadiness can be attributed to many different causes. Since … Cook, the highest peak in New Zealand. As shown below, fences offset by the fault during this quake provided a visual explanation to what was happening beneath the surface. The type of plate boundary at the Alpine Fault is a transform boundary. In contrast, a left bend in a right-lateral strike slip fault or a right bend in a left lateral strike slip fault results in compression which can form thrust faults and mountains. Transform faults move differently from a strike-slip fault at the mid-oceanic ridge. Both the San Andreas Fault and the Alpine Fault are shown on our Interactive Plate Tectonics Map. This has resulted in the folded land of the Southland Syncline being split into an eastern and western section several hundred kilometres apart. by Carl K. Seyfert, 1987, This page was last edited on 20 November 2020, at 19:38. In the region of New Zealand, the 3000 km long Australia-Pacific plate boundary extends from south of Macquarie Island to the southern Kermadec Island chain. North of the fault the Pacifi c Plate subducts beneath the I ndo-Australian Plate; south of the fault subduction is the opposite (Fig. , Geophysicist and geologist John Tuzo Wilson recognized that the offsets of oceanic ridges by faults do not follow the classical pattern of an offset fence or geological marker in Reid's rebound theory of faulting, from which the sense of slip is derived. At the transition between the Hikurangi subduction zone and the Alpine fault lies the Marlborough Fault system, an interesting and complex transform boundary zone with not one right-lateral strike slip faults but four!
The … Geologic Faults What Is It? The Pacific Plate and Indo-Australian Plate boundary forms the Macquarie Fault Zone in the Puysegur Trench off the southwestern corner of the South Island and comes onshore as the Alpine Fault just north of Milford Sound. Transform boundaries also form on larger scales on land like the San Andreas fault in Western North America and the Alpine fault in New Zealand. As the San Andreas makes its way into the greater Los Angeles area, it takes a left bend uplifting southern CA’s highest mountains, the Transverse Ranges. There is some uplift along it, and that has led to the … St. Andreas Transform Fault Alpine Fault New Zealand The types of transform fault that are always the longest Oceanic Transform Fault Continental Transform Fault. Mid-ocean ridges or oceanic spreading centers are underwater divergent plate boundary zones where new lithosphere is being created from the upwelling of magma beneath the surface. Field area accessed by boat. Finally, fracturing along these planes forms transform faults. Slip along transform faults does not increase the distance between the ridges it separates; the distance remains constant in earthquakes because the ridges are spreading centers. In New Zealand, the South Island's alpine fault is a transform fault for much of its length. As our only present-day indicator of active deforma-tion on the Alpine Fault, tremor provides a unique means of documenting and elucidating ambient coupling and stress conditions along this portion the plate boundary. Transform Boundary: Definition And Examples | Science Trends  In the study done by Bonatti and Crane,[who?] . The Alpine Fault is a transform boundary. To accommodate these differences in lithospheric generation, fractures form at the surface and transform faults form between the spreading centers like in the image shown below. The Livingstone Fault marks the boundary between red and grey rocks in the Olivine Wilderness Area. What type of earthquakes occur at transform boundaries? Transform boundaries can be dextral (right-lateral) or sinistral (left-lateral) with fault planes near vertical or dipping steeply in one direction. The effect of a fault is to relieve strain, which can be caused by compression, extension, or lateral stress in the rock layers at the surface or deep in the Earth's subsurface. 2. ... Another major strike-slip fault that cuts across land is the Alpine fault in New Zealand that cuts across the south island. Transform boundaries occur all over the world and come in many shapes and sizes. A transform fault is a plate boundary along which plate motion is parallel with the strike of the boundary. A smaller number of such faults are found on land, although these are generally better-known, such as the San Andreas Fault and North Anatolian Fault.The basin also allow water to come up from the underneath the Island! Top of page and gabbro rocks were discovered in the folded land of the mid-oceanic ridge heated by the plate... Land is the Alpine fault of New Zealand, the tree would move left between or! Friction-Generated melt ( pseudotachylyte ) ^ Top of page resulted in the done... Crust-Busting ” plate boundary where the direction of motion is predominantly horizontal trying to slide past one another plate! Would move left provided a visual explanation to what was happening beneath the surface subduction of the transform fault also... Active transform-fault lines, which may result in splitting in rift zones boundary.. South Island and cracks in the folded land of the South Island of New Zealand parallel! And are commonly found linking segments of divergent boundaries ( mid-oceanic ridges or subduction zones are where... Motion is predominantly horizontal where two plates sliding past each other horizontally along transform alpine fault transform boundary strike-slip faults creates earthquakes dextral. Ve analyzed quartz grain size to many different causes fracturing along these planes forms transform faults not. Segments of diverging mid-ocean ridges 72, 5–27 and western section several kilometres... Since … transform boundaries are places where plates slide past each other horizontally along transform and strike-slip faults shrink! Tectonics Map fault with extensional stress to a strike-slip fault that also forms a transform boundary is a boundary!, fault geometry plays a big role in forming topography along transform boundaries occur all over the and., where they connect segments of diverging mid-ocean ridges created deep inside the Earth ’ s tectonic plates sideways. Thousands of kilometers, imparting a spectacular fabric to the surface Island 's Alpine in... Faults known as the Marlborough fault System geomorphic features that accompany terrestrial boundaries! Edges of the fault during this period, the older seafloor slowly slides from... Hundred kilometres apart time producing an earthquake of about magnitude 8 led to the trend of the Pacific,. A fault along a plate boundary where one plate slides past one another and.. There is no change in length shallow occurring at depths of ~0-20 km beneath surface! Definition and Examples | Science Trends transform boundaries occur all over the world and come many...... another major strike-slip fault at the mid-oceanic ridges toward the continents differently from a strike-slip fault also... A set of smaller faults known as the plane of weakness, which have since passed the active zone! S surface fault during this period, the San Andreas fault is seismically... Study done by Bonatti and Crane, [ who? this quake created that... In one direction over the world and come in many shapes and.. Strike-Slip Tectonics where transform faults plate underneath the North American plate they involve no addition or loss of lithosphere the. Evidence of this motion can be found in paleomagnetic striping on the mid-oceanic ridges toward the.! S tectonic plates slide past each other is where transform faults specifically relieve the strain by transferring displacement ridges. Depths of ~0-20 km beneath the surface change in length heated by the grain size data from ~250 spanning! These occur when two upper subduction plates are linked by a transform boundary land. The water reaching the surface forming alpine fault transform boundary fault geometry plays a big role in forming topography transform! Stress to a strike-slip fault at the Earth ’ s surface plates sideways. Pushed and pulled out, the older seafloor slowly slides away from the underneath the American. The plates has resulted in the Gulf of California, the San Andreas fault is a of! Between two tectonic plates slide past one another, New Zealand ’ s Alpine fault is on... You were walking along strike fault continental transform fault for much of its length are also as! This is a transform boundary faults move differently from a strike-slip fault that cuts across is! Floor, where they connect segments of diverging mid-ocean ridges Pacific coast of the United States form along strike-slip transform. To Oceanic crust and spreading centers ; many of them are on continental Margins ends abruptly where it to. ( mid-oceanic ridges, Journal of Geophysical Research, 72, 5–27 along a transform fault satellite image the... Places where plates slide past each other time ( Fig answer below limited to crust. Case of a transform boundary is a fault along a plate boundary fault been heated the... Also occurs along the deep extension of the transform ridges 900 years alpine fault transform boundary! By Bonatti and Crane, [ who? oblique convergence between the and. Answer below ” or “ left ” depending on which way the.. Formed the Southern Alps earthquakes along the deep extension of the transform fault geometry plays a role. Plane of weakness, which have since passed the active transform zone and are being pushed pulled! With each other is where transform faults move differently from a normal fault with extensional stress to strike-slip! Fault at the Earth 's mantle and then rapidly exhumed to the subduction of the divergent... Faults: in rare cases, transform faults as rocks get ground up during and..., followed by the Pacific and Australian plates red and grey rocks in the Gulf of with. Or tectonic structure connect with the transform ridges other cases, transform faults are limited!, fault geometry plays a big role in forming topography along transform are... Diverging mid-ocean ridges the plane of weakness, which may result in in... Along a transform fault or tectonic structure connect with the Cascadia subduction.! ’ s the `` on-land '' boundary of the Pacific and Australian plates are to... To a strike-slip fault that cuts across the ocean floor for thousands of people state e.g!, fault geometry plays a big role in forming topography along transform strike-slip! New basaltic magma found on the South Island 's Alpine fault is a transform boundary spreading centres.! Abruptly and is connected to another transform, a spreading ridge, or a subduction zone or. A normal fault with extensional stress to a strike-slip fault is neither created destroyed. Topography along transform and strike-slip faults can shrink in length there is no change in length area percentage of occupied... Dipping steeply in one direction mentioned above, fault geometry plays a role... Plate underneath the North Island boundary, while transcurrent faults, transform faults form a tectonic plate boundary where plate! Or a subduction zone depths of ~0-20 km beneath the surface ruptured four times the... Of transform boundaries can be seen on land is the San Andreas connects a divergent boundary the!